riot.esm.js

/* Riot v5.4.1, @license MIT */
/**
 * Convert a string from camel case to dash-case
 * @param   {string} string - probably a component tag name
 * @returns {string} component name normalized
 */
function camelToDashCase(string) {
  return string.replace(/([a-z])([A-Z])/g, '$1-$2').toLowerCase();
}
/**
 * Convert a string containing dashes to camel case
 * @param   {string} string - input string
 * @returns {string} my-string -> myString
 */

function dashToCamelCase(string) {
  return string.replace(/-(\w)/g, (_, c) => c.toUpperCase());
}

/**
 * Get all the element attributes as object
 * @param   {HTMLElement} element - DOM node we want to parse
 * @returns {Object} all the attributes found as a key value pairs
 */

function DOMattributesToObject(element) {
  return Array.from(element.attributes).reduce((acc, attribute) => {
    acc[dashToCamelCase(attribute.name)] = attribute.value;
    return acc;
  }, {});
}
/**
 * Move all the child nodes from a source tag to another
 * @param   {HTMLElement} source - source node
 * @param   {HTMLElement} target - target node
 * @returns {undefined} it's a void method ¯\_(ツ)_/¯
 */
// Ignore this helper because it's needed only for svg tags

function moveChildren(source, target) {
  if (source.firstChild) {
    target.appendChild(source.firstChild);
    moveChildren(source, target);
  }
}
/**
 * Remove the child nodes from any DOM node
 * @param   {HTMLElement} node - target node
 * @returns {undefined}
 */

function cleanNode(node) {
  clearChildren(node.childNodes);
}
/**
 * Clear multiple children in a node
 * @param   {HTMLElement[]} children - direct children nodes
 * @returns {undefined}
 */

function clearChildren(children) {
  Array.from(children).forEach(removeChild);
}
/**
 * Remove a node
 * @param {HTMLElement}node - node to remove
 * @returns {undefined}
 */

const removeChild = node => node && node.parentNode && node.parentNode.removeChild(node);
/**
 * Insert before a node
 * @param {HTMLElement} newNode - node to insert
 * @param {HTMLElement} refNode - ref child
 * @returns {undefined}
 */

const insertBefore = (newNode, refNode) => refNode && refNode.parentNode && refNode.parentNode.insertBefore(newNode, refNode);
/**
 * Replace a node
 * @param {HTMLElement} newNode - new node to add to the DOM
 * @param {HTMLElement} replaced - node to replace
 * @returns {undefined}
 */

const replaceChild = (newNode, replaced) => replaced && replaced.parentNode && replaced.parentNode.replaceChild(newNode, replaced);

// Riot.js constants that can be used accross more modules
const COMPONENTS_IMPLEMENTATION_MAP$1 = new Map(),
      DOM_COMPONENT_INSTANCE_PROPERTY$1 = Symbol('riot-component'),
      PLUGINS_SET$1 = new Set(),
      IS_DIRECTIVE = 'is',
      VALUE_ATTRIBUTE = 'value',
      MOUNT_METHOD_KEY = 'mount',
      UPDATE_METHOD_KEY = 'update',
      UNMOUNT_METHOD_KEY = 'unmount',
      SHOULD_UPDATE_KEY = 'shouldUpdate',
      ON_BEFORE_MOUNT_KEY = 'onBeforeMount',
      ON_MOUNTED_KEY = 'onMounted',
      ON_BEFORE_UPDATE_KEY = 'onBeforeUpdate',
      ON_UPDATED_KEY = 'onUpdated',
      ON_BEFORE_UNMOUNT_KEY = 'onBeforeUnmount',
      ON_UNMOUNTED_KEY = 'onUnmounted',
      PROPS_KEY = 'props',
      STATE_KEY = 'state',
      SLOTS_KEY = 'slots',
      ROOT_KEY = 'root',
      IS_PURE_SYMBOL = Symbol('pure'),
      IS_COMPONENT_UPDATING = Symbol('is_updating'),
      PARENT_KEY_SYMBOL = Symbol('parent'),
      ATTRIBUTES_KEY_SYMBOL = Symbol('attributes'),
      TEMPLATE_KEY_SYMBOL = Symbol('template');

var globals = /*#__PURE__*/Object.freeze({
  __proto__: null,
  COMPONENTS_IMPLEMENTATION_MAP: COMPONENTS_IMPLEMENTATION_MAP$1,
  DOM_COMPONENT_INSTANCE_PROPERTY: DOM_COMPONENT_INSTANCE_PROPERTY$1,
  PLUGINS_SET: PLUGINS_SET$1,
  IS_DIRECTIVE: IS_DIRECTIVE,
  VALUE_ATTRIBUTE: VALUE_ATTRIBUTE,
  MOUNT_METHOD_KEY: MOUNT_METHOD_KEY,
  UPDATE_METHOD_KEY: UPDATE_METHOD_KEY,
  UNMOUNT_METHOD_KEY: UNMOUNT_METHOD_KEY,
  SHOULD_UPDATE_KEY: SHOULD_UPDATE_KEY,
  ON_BEFORE_MOUNT_KEY: ON_BEFORE_MOUNT_KEY,
  ON_MOUNTED_KEY: ON_MOUNTED_KEY,
  ON_BEFORE_UPDATE_KEY: ON_BEFORE_UPDATE_KEY,
  ON_UPDATED_KEY: ON_UPDATED_KEY,
  ON_BEFORE_UNMOUNT_KEY: ON_BEFORE_UNMOUNT_KEY,
  ON_UNMOUNTED_KEY: ON_UNMOUNTED_KEY,
  PROPS_KEY: PROPS_KEY,
  STATE_KEY: STATE_KEY,
  SLOTS_KEY: SLOTS_KEY,
  ROOT_KEY: ROOT_KEY,
  IS_PURE_SYMBOL: IS_PURE_SYMBOL,
  IS_COMPONENT_UPDATING: IS_COMPONENT_UPDATING,
  PARENT_KEY_SYMBOL: PARENT_KEY_SYMBOL,
  ATTRIBUTES_KEY_SYMBOL: ATTRIBUTES_KEY_SYMBOL,
  TEMPLATE_KEY_SYMBOL: TEMPLATE_KEY_SYMBOL
});

const EACH = 0;
const IF = 1;
const SIMPLE = 2;
const TAG = 3;
const SLOT = 4;
var bindingTypes = {
  EACH,
  IF,
  SIMPLE,
  TAG,
  SLOT
};

const ATTRIBUTE = 0;
const EVENT = 1;
const TEXT = 2;
const VALUE = 3;
var expressionTypes = {
  ATTRIBUTE,
  EVENT,
  TEXT,
  VALUE
};

const HEAD_SYMBOL = Symbol('head');
const TAIL_SYMBOL = Symbol('tail');

/**
 * Create the <template> fragments comment nodes
 * @return {Object} {{head: Comment, tail: Comment}}
 */

function createHeadTailPlaceholders() {
  const head = document.createComment('fragment head');
  const tail = document.createComment('fragment tail');
  head[HEAD_SYMBOL] = true;
  tail[TAIL_SYMBOL] = true;
  return {
    head,
    tail
  };
}

/**
 * Create the template meta object in case of <template> fragments
 * @param   {TemplateChunk} componentTemplate - template chunk object
 * @returns {Object} the meta property that will be passed to the mount function of the TemplateChunk
 */

function createTemplateMeta(componentTemplate) {
  const fragment = componentTemplate.dom.cloneNode(true);
  const {
    head,
    tail
  } = createHeadTailPlaceholders();
  return {
    avoidDOMInjection: true,
    fragment,
    head,
    tail,
    children: [head, ...Array.from(fragment.childNodes), tail]
  };
}

/**
 * Get the current <template> fragment children located in between the head and tail comments
 * @param {Comment} head - head comment node
 * @param {Comment} tail - tail comment node
 * @return {Array[]} children list of the nodes found in this template fragment
 */

function getFragmentChildren(_ref) {
  let {
    head,
    tail
  } = _ref;
  const nodes = walkNodes([head], head.nextSibling, n => n === tail, false);
  nodes.push(tail);
  return nodes;
}
/**
 * Recursive function to walk all the <template> children nodes
 * @param {Array[]} children - children nodes collection
 * @param {ChildNode} node - current node
 * @param {Function} check - exit function check
 * @param {boolean} isFilterActive - filter flag to skip nodes managed by other bindings
 * @returns {Array[]} children list of the nodes found in this template fragment
 */

function walkNodes(children, node, check, isFilterActive) {
  const {
    nextSibling
  } = node; // filter tail and head nodes together with all the nodes in between
  // this is needed only to fix a really ugly edge case https://github.com/riot/riot/issues/2892

  if (!isFilterActive && !node[HEAD_SYMBOL] && !node[TAIL_SYMBOL]) {
    children.push(node);
  }

  if (!nextSibling || check(node)) return children;
  return walkNodes(children, nextSibling, check, // activate the filters to skip nodes between <template> fragments that will be managed by other bindings
  isFilterActive && !node[TAIL_SYMBOL] || nextSibling[HEAD_SYMBOL]);
}

/**
 * Quick type checking
 * @param   {*} element - anything
 * @param   {string} type - type definition
 * @returns {boolean} true if the type corresponds
 */
function checkType(element, type) {
  return typeof element === type;
}
/**
 * Check if an element is part of an svg
 * @param   {HTMLElement}  el - element to check
 * @returns {boolean} true if we are in an svg context
 */

function isSvg(el) {
  const owner = el.ownerSVGElement;
  return !!owner || owner === null;
}
/**
 * Check if an element is a template tag
 * @param   {HTMLElement}  el - element to check
 * @returns {boolean} true if it's a <template>
 */

function isTemplate(el) {
  return !isNil(el.content);
}
/**
 * Check that will be passed if its argument is a function
 * @param   {*} value - value to check
 * @returns {boolean} - true if the value is a function
 */

function isFunction(value) {
  return checkType(value, 'function');
}
/**
 * Check if a value is a Boolean
 * @param   {*}  value - anything
 * @returns {boolean} true only for the value is a boolean
 */

function isBoolean(value) {
  return checkType(value, 'boolean');
}
/**
 * Check if a value is an Object
 * @param   {*}  value - anything
 * @returns {boolean} true only for the value is an object
 */

function isObject(value) {
  return !isNil(value) && value.constructor === Object;
}
/**
 * Check if a value is null or undefined
 * @param   {*}  value - anything
 * @returns {boolean} true only for the 'undefined' and 'null' types
 */

function isNil(value) {
  return value === null || value === undefined;
}

/**
 * ISC License
 *
 * Copyright (c) 2020, Andrea Giammarchi, @WebReflection
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
 * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
 * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
 * PERFORMANCE OF THIS SOFTWARE.
 */
// fork of https://github.com/WebReflection/udomdiff version 1.1.0
// due to https://github.com/WebReflection/udomdiff/pull/2

/* eslint-disable */

/**
 * @param {Node[]} a The list of current/live children
 * @param {Node[]} b The list of future children
 * @param {(entry: Node, action: number) => Node} get
 * The callback invoked per each entry related DOM operation.
 * @param {Node} [before] The optional node used as anchor to insert before.
 * @returns {Node[]} The same list of future children.
 */

var udomdiff = ((a, b, get, before) => {
  const bLength = b.length;
  let aEnd = a.length;
  let bEnd = bLength;
  let aStart = 0;
  let bStart = 0;
  let map = null;

  while (aStart < aEnd || bStart < bEnd) {
    // append head, tail, or nodes in between: fast path
    if (aEnd === aStart) {
      // we could be in a situation where the rest of nodes that
      // need to be added are not at the end, and in such case
      // the node to `insertBefore`, if the index is more than 0
      // must be retrieved, otherwise it's gonna be the first item.
      const node = bEnd < bLength ? bStart ? get(b[bStart - 1], -0).nextSibling : get(b[bEnd - bStart], 0) : before;

      while (bStart < bEnd) insertBefore(get(b[bStart++], 1), node);
    } // remove head or tail: fast path
    else if (bEnd === bStart) {
        while (aStart < aEnd) {
          // remove the node only if it's unknown or not live
          if (!map || !map.has(a[aStart])) removeChild(get(a[aStart], -1));
          aStart++;
        }
      } // same node: fast path
      else if (a[aStart] === b[bStart]) {
          aStart++;
          bStart++;
        } // same tail: fast path
        else if (a[aEnd - 1] === b[bEnd - 1]) {
            aEnd--;
            bEnd--;
          } // The once here single last swap "fast path" has been removed in v1.1.0
          // https://github.com/WebReflection/udomdiff/blob/single-final-swap/esm/index.js#L69-L85
          // reverse swap: also fast path
          else if (a[aStart] === b[bEnd - 1] && b[bStart] === a[aEnd - 1]) {
              // this is a "shrink" operation that could happen in these cases:
              // [1, 2, 3, 4, 5]
              // [1, 4, 3, 2, 5]
              // or asymmetric too
              // [1, 2, 3, 4, 5]
              // [1, 2, 3, 5, 6, 4]
              const node = get(a[--aEnd], -1).nextSibling;
              insertBefore(get(b[bStart++], 1), get(a[aStart++], -1).nextSibling);
              insertBefore(get(b[--bEnd], 1), node); // mark the future index as identical (yeah, it's dirty, but cheap 👍)
              // The main reason to do this, is that when a[aEnd] will be reached,
              // the loop will likely be on the fast path, as identical to b[bEnd].
              // In the best case scenario, the next loop will skip the tail,
              // but in the worst one, this node will be considered as already
              // processed, bailing out pretty quickly from the map index check

              a[aEnd] = b[bEnd];
            } // map based fallback, "slow" path
            else {
                // the map requires an O(bEnd - bStart) operation once
                // to store all future nodes indexes for later purposes.
                // In the worst case scenario, this is a full O(N) cost,
                // and such scenario happens at least when all nodes are different,
                // but also if both first and last items of the lists are different
                if (!map) {
                  map = new Map();
                  let i = bStart;

                  while (i < bEnd) map.set(b[i], i++);
                } // if it's a future node, hence it needs some handling


                if (map.has(a[aStart])) {
                  // grab the index of such node, 'cause it might have been processed
                  const index = map.get(a[aStart]); // if it's not already processed, look on demand for the next LCS

                  if (bStart < index && index < bEnd) {
                    let i = aStart; // counts the amount of nodes that are the same in the future

                    let sequence = 1;

                    while (++i < aEnd && i < bEnd && map.get(a[i]) === index + sequence) sequence++; // effort decision here: if the sequence is longer than replaces
                    // needed to reach such sequence, which would brings again this loop
                    // to the fast path, prepend the difference before a sequence,
                    // and move only the future list index forward, so that aStart
                    // and bStart will be aligned again, hence on the fast path.
                    // An example considering aStart and bStart are both 0:
                    // a: [1, 2, 3, 4]
                    // b: [7, 1, 2, 3, 6]
                    // this would place 7 before 1 and, from that time on, 1, 2, and 3
                    // will be processed at zero cost


                    if (sequence > index - bStart) {
                      const node = get(a[aStart], 0);

                      while (bStart < index) insertBefore(get(b[bStart++], 1), node);
                    } // if the effort wasn't good enough, fallback to a replace,
                    // moving both source and target indexes forward, hoping that some
                    // similar node will be found later on, to go back to the fast path
                    else {
                        replaceChild(get(b[bStart++], 1), get(a[aStart++], -1));
                      }
                  } // otherwise move the source forward, 'cause there's nothing to do
                  else aStart++;
                } // this node has no meaning in the future list, so it's more than safe
                // to remove it, and check the next live node out instead, meaning
                // that only the live list index should be forwarded
                else removeChild(get(a[aStart++], -1));
              }
  }

  return b;
});

const UNMOUNT_SCOPE = Symbol('unmount');
const EachBinding = {
  // dynamic binding properties
  // childrenMap: null,
  // node: null,
  // root: null,
  // condition: null,
  // evaluate: null,
  // template: null,
  // isTemplateTag: false,
  nodes: [],

  // getKey: null,
  // indexName: null,
  // itemName: null,
  // afterPlaceholder: null,
  // placeholder: null,
  // API methods
  mount(scope, parentScope) {
    return this.update(scope, parentScope);
  },

  update(scope, parentScope) {
    const {
      placeholder,
      nodes,
      childrenMap
    } = this;
    const collection = scope === UNMOUNT_SCOPE ? null : this.evaluate(scope);
    const items = collection ? Array.from(collection) : []; // prepare the diffing

    const {
      newChildrenMap,
      batches,
      futureNodes
    } = createPatch(items, scope, parentScope, this); // patch the DOM only if there are new nodes

    udomdiff(nodes, futureNodes, patch(Array.from(childrenMap.values()), parentScope), placeholder); // trigger the mounts and the updates

    batches.forEach(fn => fn()); // update the children map

    this.childrenMap = newChildrenMap;
    this.nodes = futureNodes; // make sure that the loop edge nodes are marked

    markEdgeNodes(this.nodes);
    return this;
  },

  unmount(scope, parentScope) {
    this.update(UNMOUNT_SCOPE, parentScope);
    return this;
  }

};
/**
 * Patch the DOM while diffing
 * @param   {any[]} redundant - list of all the children (template, nodes, context) added via each
 * @param   {*} parentScope - scope of the parent template
 * @returns {Function} patch function used by domdiff
 */

function patch(redundant, parentScope) {
  return (item, info) => {
    if (info < 0) {
      // get the last element added to the childrenMap saved previously
      const element = redundant[redundant.length - 1];

      if (element) {
        // get the nodes and the template in stored in the last child of the childrenMap
        const {
          template,
          nodes,
          context
        } = element; // remove the last node (notice <template> tags might have more children nodes)

        nodes.pop(); // notice that we pass null as last argument because
        // the root node and its children will be removed by domdiff

        if (nodes.length === 0) {
          // we have cleared all the children nodes and we can unmount this template
          redundant.pop();
          template.unmount(context, parentScope, null);
        }
      }
    }

    return item;
  };
}
/**
 * Check whether a template must be filtered from a loop
 * @param   {Function} condition - filter function
 * @param   {Object} context - argument passed to the filter function
 * @returns {boolean} true if this item should be skipped
 */


function mustFilterItem(condition, context) {
  return condition ? Boolean(condition(context)) === false : false;
}
/**
 * Extend the scope of the looped template
 * @param   {Object} scope - current template scope
 * @param   {string} options.itemName - key to identify the looped item in the new context
 * @param   {string} options.indexName - key to identify the index of the looped item
 * @param   {number} options.index - current index
 * @param   {*} options.item - collection item looped
 * @returns {Object} enhanced scope object
 */


function extendScope(scope, _ref) {
  let {
    itemName,
    indexName,
    index,
    item
  } = _ref;
  scope[itemName] = item;
  if (indexName) scope[indexName] = index;
  return scope;
}
/**
 * Mark the first and last nodes in order to ignore them in case we need to retrieve the <template> fragment nodes
 * @param {Array[]} nodes - each binding nodes list
 * @returns {undefined} void function
 */


function markEdgeNodes(nodes) {
  const first = nodes[0];
  const last = nodes[nodes.length - 1];
  if (first) first[HEAD_SYMBOL] = true;
  if (last) last[TAIL_SYMBOL] = true;
}
/**
 * Loop the current template items
 * @param   {Array} items - expression collection value
 * @param   {*} scope - template scope
 * @param   {*} parentScope - scope of the parent template
 * @param   {EeachBinding} binding - each binding object instance
 * @returns {Object} data
 * @returns {Map} data.newChildrenMap - a Map containing the new children template structure
 * @returns {Array} data.batches - array containing the template lifecycle functions to trigger
 * @returns {Array} data.futureNodes - array containing the nodes we need to diff
 */


function createPatch(items, scope, parentScope, binding) {
  const {
    condition,
    template,
    childrenMap,
    itemName,
    getKey,
    indexName,
    root,
    isTemplateTag
  } = binding;
  const newChildrenMap = new Map();
  const batches = [];
  const futureNodes = [];
  items.forEach((item, index) => {
    const context = extendScope(Object.create(scope), {
      itemName,
      indexName,
      index,
      item
    });
    const key = getKey ? getKey(context) : index;
    const oldItem = childrenMap.get(key);
    const nodes = [];

    if (mustFilterItem(condition, context)) {
      return;
    }

    const mustMount = !oldItem;
    const componentTemplate = oldItem ? oldItem.template : template.clone();
    const el = componentTemplate.el || root.cloneNode();
    const meta = isTemplateTag && mustMount ? createTemplateMeta(componentTemplate) : componentTemplate.meta;

    if (mustMount) {
      batches.push(() => componentTemplate.mount(el, context, parentScope, meta));
    } else {
      batches.push(() => componentTemplate.update(context, parentScope));
    } // create the collection of nodes to update or to add
    // in case of template tags we need to add all its children nodes


    if (isTemplateTag) {
      nodes.push(...(mustMount ? meta.children : getFragmentChildren(meta)));
    } else {
      nodes.push(el);
    } // delete the old item from the children map


    childrenMap.delete(key);
    futureNodes.push(...nodes); // update the children map

    newChildrenMap.set(key, {
      nodes,
      template: componentTemplate,
      context,
      index
    });
  });
  return {
    newChildrenMap,
    batches,
    futureNodes
  };
}

function create$6(node, _ref2) {
  let {
    evaluate,
    condition,
    itemName,
    indexName,
    getKey,
    template
  } = _ref2;
  const placeholder = document.createTextNode('');
  const root = node.cloneNode();
  insertBefore(placeholder, node);
  removeChild(node);
  return Object.assign({}, EachBinding, {
    childrenMap: new Map(),
    node,
    root,
    condition,
    evaluate,
    isTemplateTag: isTemplate(root),
    template: template.createDOM(node),
    getKey,
    indexName,
    itemName,
    placeholder
  });
}

/**
 * Binding responsible for the `if` directive
 */

const IfBinding = {
  // dynamic binding properties
  // node: null,
  // evaluate: null,
  // isTemplateTag: false,
  // placeholder: null,
  // template: null,
  // API methods
  mount(scope, parentScope) {
    return this.update(scope, parentScope);
  },

  update(scope, parentScope) {
    const value = !!this.evaluate(scope);
    const mustMount = !this.value && value;
    const mustUnmount = this.value && !value;

    const mount = () => {
      const pristine = this.node.cloneNode();
      insertBefore(pristine, this.placeholder);
      this.template = this.template.clone();
      this.template.mount(pristine, scope, parentScope);
    };

    switch (true) {
      case mustMount:
        mount();
        break;

      case mustUnmount:
        this.unmount(scope);
        break;

      default:
        if (value) this.template.update(scope, parentScope);
    }

    this.value = value;
    return this;
  },

  unmount(scope, parentScope) {
    this.template.unmount(scope, parentScope, true);
    return this;
  }

};
function create$5(node, _ref) {
  let {
    evaluate,
    template
  } = _ref;
  const placeholder = document.createTextNode('');
  insertBefore(placeholder, node);
  removeChild(node);
  return Object.assign({}, IfBinding, {
    node,
    evaluate,
    placeholder,
    template: template.createDOM(node)
  });
}

/**
 * Throw an error with a descriptive message
 * @param   { string } message - error message
 * @returns { undefined } hoppla.. at this point the program should stop working
 */

function panic(message) {
  throw new Error(message);
}
/**
 * Returns the memoized (cached) function.
 * // borrowed from https://www.30secondsofcode.org/js/s/memoize
 * @param {Function} fn - function to memoize
 * @returns {Function} memoize function
 */

function memoize(fn) {
  const cache = new Map();

  const cached = val => {
    return cache.has(val) ? cache.get(val) : cache.set(val, fn.call(this, val)) && cache.get(val);
  };

  cached.cache = cache;
  return cached;
}
/**
 * Evaluate a list of attribute expressions
 * @param   {Array} attributes - attribute expressions generated by the riot compiler
 * @returns {Object} key value pairs with the result of the computation
 */

function evaluateAttributeExpressions(attributes) {
  return attributes.reduce((acc, attribute) => {
    const {
      value,
      type
    } = attribute;

    switch (true) {
      // spread attribute
      case !attribute.name && type === ATTRIBUTE:
        return Object.assign({}, acc, value);
      // value attribute

      case type === VALUE:
        acc.value = attribute.value;
        break;
      // normal attributes

      default:
        acc[dashToCamelCase(attribute.name)] = attribute.value;
    }

    return acc;
  }, {});
}

const ElementProto = typeof Element === 'undefined' ? {} : Element.prototype;
const isNativeHtmlProperty = memoize(name => ElementProto.hasOwnProperty(name)); // eslint-disable-line

/**
 * Add all the attributes provided
 * @param   {HTMLElement} node - target node
 * @param   {Object} attributes - object containing the attributes names and values
 * @returns {undefined} sorry it's a void function :(
 */

function setAllAttributes(node, attributes) {
  Object.entries(attributes).forEach(_ref => {
    let [name, value] = _ref;
    return attributeExpression(node, {
      name
    }, value);
  });
}
/**
 * Remove all the attributes provided
 * @param   {HTMLElement} node - target node
 * @param   {Object} newAttributes - object containing all the new attribute names
 * @param   {Object} oldAttributes - object containing all the old attribute names
 * @returns {undefined} sorry it's a void function :(
 */


function removeAllAttributes(node, newAttributes, oldAttributes) {
  const newKeys = newAttributes ? Object.keys(newAttributes) : [];
  Object.keys(oldAttributes).filter(name => !newKeys.includes(name)).forEach(attribute => node.removeAttribute(attribute));
}
/**
 * Check whether the attribute value can be rendered
 * @param {*} value - expression value
 * @returns {boolean} true if we can render this attribute value
 */


function canRenderAttribute(value) {
  return value === true || ['string', 'number'].includes(typeof value);
}
/**
 * Check whether the attribute should be removed
 * @param {*} value - expression value
 * @returns {boolean} boolean - true if the attribute can be removed}
 */


function shouldRemoveAttribute(value) {
  return isNil(value) || value === false || value === '';
}
/**
 * This methods handles the DOM attributes updates
 * @param   {HTMLElement} node - target node
 * @param   {Object} expression - expression object
 * @param   {string} expression.name - attribute name
 * @param   {*} value - new expression value
 * @param   {*} oldValue - the old expression cached value
 * @returns {undefined}
 */


function attributeExpression(node, _ref2, value, oldValue) {
  let {
    name
  } = _ref2;

  // is it a spread operator? {...attributes}
  if (!name) {
    if (oldValue) {
      // remove all the old attributes
      removeAllAttributes(node, value, oldValue);
    } // is the value still truthy?


    if (value) {
      setAllAttributes(node, value);
    }

    return;
  } // handle boolean attributes


  if (!isNativeHtmlProperty(name) && (isBoolean(value) || isObject(value) || isFunction(value))) {
    node[name] = value;
  }

  if (shouldRemoveAttribute(value)) {
    node.removeAttribute(name);
  } else if (canRenderAttribute(value)) {
    node.setAttribute(name, normalizeValue(name, value));
  }
}
/**
 * Get the value as string
 * @param   {string} name - attribute name
 * @param   {*} value - user input value
 * @returns {string} input value as string
 */

function normalizeValue(name, value) {
  // be sure that expressions like selected={ true } will be always rendered as selected='selected'
  if (value === true) return name;
  return value;
}

const RE_EVENTS_PREFIX = /^on/;

const getCallbackAndOptions = value => Array.isArray(value) ? value : [value, false]; // see also https://medium.com/@WebReflection/dom-handleevent-a-cross-platform-standard-since-year-2000-5bf17287fd38


const EventListener = {
  handleEvent(event) {
    this[event.type](event);
  }

};
const ListenersWeakMap = new WeakMap();

const createListener = node => {
  const listener = Object.create(EventListener);
  ListenersWeakMap.set(node, listener);
  return listener;
};
/**
 * Set a new event listener
 * @param   {HTMLElement} node - target node
 * @param   {Object} expression - expression object
 * @param   {string} expression.name - event name
 * @param   {*} value - new expression value
 * @returns {value} the callback just received
 */


function eventExpression(node, _ref, value) {
  let {
    name
  } = _ref;
  const normalizedEventName = name.replace(RE_EVENTS_PREFIX, '');
  const eventListener = ListenersWeakMap.get(node) || createListener(node);
  const [callback, options] = getCallbackAndOptions(value);
  const handler = eventListener[normalizedEventName];
  const mustRemoveEvent = handler && !callback;
  const mustAddEvent = callback && !handler;

  if (mustRemoveEvent) {
    node.removeEventListener(normalizedEventName, eventListener);
  }

  if (mustAddEvent) {
    node.addEventListener(normalizedEventName, eventListener, options);
  }

  eventListener[normalizedEventName] = callback;
}

/**
 * Normalize the user value in order to render a empty string in case of falsy values
 * @param   {*} value - user input value
 * @returns {string} hopefully a string
 */

function normalizeStringValue(value) {
  return isNil(value) ? '' : value;
}

/**
 * Get the the target text node to update or create one from of a comment node
 * @param   {HTMLElement} node - any html element containing childNodes
 * @param   {number} childNodeIndex - index of the text node in the childNodes list
 * @returns {HTMLTextNode} the text node to update
 */

const getTextNode = (node, childNodeIndex) => {
  const target = node.childNodes[childNodeIndex];

  if (target.nodeType === Node.COMMENT_NODE) {
    const textNode = document.createTextNode('');
    node.replaceChild(textNode, target);
    return textNode;
  }

  return target;
};
/**
 * This methods handles a simple text expression update
 * @param   {HTMLElement} node - target node
 * @param   {Object} data - expression object
 * @param   {*} value - new expression value
 * @returns {undefined}
 */

function textExpression(node, data, value) {
  node.data = normalizeStringValue(value);
}

/**
 * This methods handles the input fileds value updates
 * @param   {HTMLElement} node - target node
 * @param   {Object} expression - expression object
 * @param   {*} value - new expression value
 * @returns {undefined}
 */

function valueExpression(node, expression, value) {
  node.value = normalizeStringValue(value);
}

var expressions = {
  [ATTRIBUTE]: attributeExpression,
  [EVENT]: eventExpression,
  [TEXT]: textExpression,
  [VALUE]: valueExpression
};

const Expression = {
  // Static props
  // node: null,
  // value: null,
  // API methods

  /**
   * Mount the expression evaluating its initial value
   * @param   {*} scope - argument passed to the expression to evaluate its current values
   * @returns {Expression} self
   */
  mount(scope) {
    // hopefully a pure function
    this.value = this.evaluate(scope); // IO() DOM updates

    apply(this, this.value);
    return this;
  },

  /**
   * Update the expression if its value changed
   * @param   {*} scope - argument passed to the expression to evaluate its current values
   * @returns {Expression} self
   */
  update(scope) {
    // pure function
    const value = this.evaluate(scope);

    if (this.value !== value) {
      // IO() DOM updates
      apply(this, value);
      this.value = value;
    }

    return this;
  },

  /**
   * Expression teardown method
   * @returns {Expression} self
   */
  unmount() {
    // unmount only the event handling expressions
    if (this.type === EVENT) apply(this, null);
    return this;
  }

};
/**
 * IO() function to handle the DOM updates
 * @param {Expression} expression - expression object
 * @param {*} value - current expression value
 * @returns {undefined}
 */

function apply(expression, value) {
  return expressions[expression.type](expression.node, expression, value, expression.value);
}

function create$4(node, data) {
  return Object.assign({}, Expression, data, {
    node: data.type === TEXT ? getTextNode(node, data.childNodeIndex) : node
  });
}

/**
 * Create a flat object having as keys a list of methods that if dispatched will propagate
 * on the whole collection
 * @param   {Array} collection - collection to iterate
 * @param   {Array<string>} methods - methods to execute on each item of the collection
 * @param   {*} context - context returned by the new methods created
 * @returns {Object} a new object to simplify the the nested methods dispatching
 */
function flattenCollectionMethods(collection, methods, context) {
  return methods.reduce((acc, method) => {
    return Object.assign({}, acc, {
      [method]: scope => {
        return collection.map(item => item[method](scope)) && context;
      }
    });
  }, {});
}

function create$3(node, _ref) {
  let {
    expressions
  } = _ref;
  return Object.assign({}, flattenCollectionMethods(expressions.map(expression => create$4(node, expression)), ['mount', 'update', 'unmount']));
}

function extendParentScope(attributes, scope, parentScope) {
  if (!attributes || !attributes.length) return parentScope;
  const expressions = attributes.map(attr => Object.assign({}, attr, {
    value: attr.evaluate(scope)
  }));
  return Object.assign(Object.create(parentScope || null), evaluateAttributeExpressions(expressions));
} // this function is only meant to fix an edge case
// https://github.com/riot/riot/issues/2842


const getRealParent = (scope, parentScope) => scope[PARENT_KEY_SYMBOL] || parentScope;

const SlotBinding = {
  // dynamic binding properties
  // node: null,
  // name: null,
  attributes: [],

  // template: null,
  getTemplateScope(scope, parentScope) {
    return extendParentScope(this.attributes, scope, parentScope);
  },

  // API methods
  mount(scope, parentScope) {
    const templateData = scope.slots ? scope.slots.find(_ref => {
      let {
        id
      } = _ref;
      return id === this.name;
    }) : false;
    const {
      parentNode
    } = this.node;
    const realParent = getRealParent(scope, parentScope);
    this.template = templateData && create(templateData.html, templateData.bindings).createDOM(parentNode);

    if (this.template) {
      this.template.mount(this.node, this.getTemplateScope(scope, realParent), realParent);
      this.template.children = Array.from(this.node.childNodes);
      moveSlotInnerContent(this.node);
    }

    removeChild(this.node);
    return this;
  },

  update(scope, parentScope) {
    if (this.template) {
      const realParent = getRealParent(scope, parentScope);
      this.template.update(this.getTemplateScope(scope, realParent), realParent);
    }

    return this;
  },

  unmount(scope, parentScope, mustRemoveRoot) {
    if (this.template) {
      this.template.unmount(this.getTemplateScope(scope, parentScope), null, mustRemoveRoot);
    }

    return this;
  }

};
/**
 * Move the inner content of the slots outside of them
 * @param   {HTMLElement} slot - slot node
 * @returns {undefined} it's a void method ¯\_(ツ)_/¯
 */

function moveSlotInnerContent(slot) {
  const child = slot && slot.firstChild;
  if (!child) return;
  insertBefore(child, slot);
  moveSlotInnerContent(slot);
}
/**
 * Create a single slot binding
 * @param   {HTMLElement} node - slot node
 * @param   {string} options.name - slot id
 * @returns {Object} Slot binding object
 */


function createSlot(node, _ref2) {
  let {
    name,
    attributes
  } = _ref2;
  return Object.assign({}, SlotBinding, {
    attributes,
    node,
    name
  });
}

/**
 * Create a new tag object if it was registered before, otherwise fallback to the simple
 * template chunk
 * @param   {Function} component - component factory function
 * @param   {Array<Object>} slots - array containing the slots markup
 * @param   {Array} attributes - dynamic attributes that will be received by the tag element
 * @returns {TagImplementation|TemplateChunk} a tag implementation or a template chunk as fallback
 */

function getTag(component, slots, attributes) {
  if (slots === void 0) {
    slots = [];
  }

  if (attributes === void 0) {
    attributes = [];
  }

  // if this tag was registered before we will return its implementation
  if (component) {
    return component({
      slots,
      attributes
    });
  } // otherwise we return a template chunk


  return create(slotsToMarkup(slots), [...slotBindings(slots), {
    // the attributes should be registered as binding
    // if we fallback to a normal template chunk
    expressions: attributes.map(attr => {
      return Object.assign({
        type: ATTRIBUTE
      }, attr);
    })
  }]);
}
/**
 * Merge all the slots bindings into a single array
 * @param   {Array<Object>} slots - slots collection
 * @returns {Array<Bindings>} flatten bindings array
 */


function slotBindings(slots) {
  return slots.reduce((acc, _ref) => {
    let {
      bindings
    } = _ref;
    return acc.concat(bindings);
  }, []);
}
/**
 * Merge all the slots together in a single markup string
 * @param   {Array<Object>} slots - slots collection
 * @returns {string} markup of all the slots in a single string
 */


function slotsToMarkup(slots) {
  return slots.reduce((acc, slot) => {
    return acc + slot.html;
  }, '');
}

const TagBinding = {
  // dynamic binding properties
  // node: null,
  // evaluate: null,
  // name: null,
  // slots: null,
  // tag: null,
  // attributes: null,
  // getComponent: null,
  mount(scope) {
    return this.update(scope);
  },

  update(scope, parentScope) {
    const name = this.evaluate(scope); // simple update

    if (name && name === this.name) {
      this.tag.update(scope);
    } else {
      // unmount the old tag if it exists
      this.unmount(scope, parentScope, true); // mount the new tag

      this.name = name;
      this.tag = getTag(this.getComponent(name), this.slots, this.attributes);
      this.tag.mount(this.node, scope);
    }

    return this;
  },

  unmount(scope, parentScope, keepRootTag) {
    if (this.tag) {
      // keep the root tag
      this.tag.unmount(keepRootTag);
    }

    return this;
  }

};
function create$2(node, _ref2) {
  let {
    evaluate,
    getComponent,
    slots,
    attributes
  } = _ref2;
  return Object.assign({}, TagBinding, {
    node,
    evaluate,
    slots,
    attributes,
    getComponent
  });
}

var bindings = {
  [IF]: create$5,
  [SIMPLE]: create$3,
  [EACH]: create$6,
  [TAG]: create$2,
  [SLOT]: createSlot
};

/**
 * Text expressions in a template tag will get childNodeIndex value normalized
 * depending on the position of the <template> tag offset
 * @param   {Expression[]} expressions - riot expressions array
 * @param   {number} textExpressionsOffset - offset of the <template> tag
 * @returns {Expression[]} expressions containing the text expressions normalized
 */

function fixTextExpressionsOffset(expressions, textExpressionsOffset) {
  return expressions.map(e => e.type === TEXT ? Object.assign({}, e, {
    childNodeIndex: e.childNodeIndex + textExpressionsOffset
  }) : e);
}
/**
 * Bind a new expression object to a DOM node
 * @param   {HTMLElement} root - DOM node where to bind the expression
 * @param   {Object} binding - binding data
 * @param   {number|null} templateTagOffset - if it's defined we need to fix the text expressions childNodeIndex offset
 * @returns {Binding} Binding object
 */


function create$1(root, binding, templateTagOffset) {
  const {
    selector,
    type,
    redundantAttribute,
    expressions
  } = binding; // find the node to apply the bindings

  const node = selector ? root.querySelector(selector) : root; // remove eventually additional attributes created only to select this node

  if (redundantAttribute) node.removeAttribute(redundantAttribute);
  const bindingExpressions = expressions || []; // init the binding

  return (bindings[type] || bindings[SIMPLE])(node, Object.assign({}, binding, {
    expressions: templateTagOffset && !selector ? fixTextExpressionsOffset(bindingExpressions, templateTagOffset) : bindingExpressions
  }));
}

function createHTMLTree(html, root) {
  const template = isTemplate(root) ? root : document.createElement('template');
  template.innerHTML = html;
  return template.content;
} // for svg nodes we need a bit more work


function createSVGTree(html, container) {
  // create the SVGNode
  const svgNode = container.ownerDocument.importNode(new window.DOMParser().parseFromString(`<svg xmlns="http://www.w3.org/2000/svg">${html}</svg>`, 'application/xml').documentElement, true);
  return svgNode;
}
/**
 * Create the DOM that will be injected
 * @param {Object} root - DOM node to find out the context where the fragment will be created
 * @param   {string} html - DOM to create as string
 * @returns {HTMLDocumentFragment|HTMLElement} a new html fragment
 */


function createDOMTree(root, html) {
  if (isSvg(root)) return createSVGTree(html, root);
  return createHTMLTree(html, root);
}

/**
 * Inject the DOM tree into a target node
 * @param   {HTMLElement} el - target element
 * @param   {HTMLFragment|SVGElement} dom - dom tree to inject
 * @returns {undefined}
 */

function injectDOM(el, dom) {
  switch (true) {
    case isSvg(el):
      moveChildren(dom, el);
      break;

    case isTemplate(el):
      el.parentNode.replaceChild(dom, el);
      break;

    default:
      el.appendChild(dom);
  }
}

/**
 * Create the Template DOM skeleton
 * @param   {HTMLElement} el - root node where the DOM will be injected
 * @param   {string} html - markup that will be injected into the root node
 * @returns {HTMLFragment} fragment that will be injected into the root node
 */

function createTemplateDOM(el, html) {
  return html && (typeof html === 'string' ? createDOMTree(el, html) : html);
}
/**
 * Template Chunk model
 * @type {Object}
 */


const TemplateChunk = Object.freeze({
  // Static props
  // bindings: null,
  // bindingsData: null,
  // html: null,
  // isTemplateTag: false,
  // fragment: null,
  // children: null,
  // dom: null,
  // el: null,

  /**
   * Create the template DOM structure that will be cloned on each mount
   * @param   {HTMLElement} el - the root node
   * @returns {TemplateChunk} self
   */
  createDOM(el) {
    // make sure that the DOM gets created before cloning the template
    this.dom = this.dom || createTemplateDOM(el, this.html);
    return this;
  },

  // API methods

  /**
   * Attach the template to a DOM node
   * @param   {HTMLElement} el - target DOM node
   * @param   {*} scope - template data
   * @param   {*} parentScope - scope of the parent template tag
   * @param   {Object} meta - meta properties needed to handle the <template> tags in loops
   * @returns {TemplateChunk} self
   */
  mount(el, scope, parentScope, meta) {
    if (meta === void 0) {
      meta = {};
    }

    if (!el) throw new Error('Please provide DOM node to mount properly your template');
    if (this.el) this.unmount(scope); // <template> tags require a bit more work
    // the template fragment might be already created via meta outside of this call

    const {
      fragment,
      children,
      avoidDOMInjection
    } = meta; // <template> bindings of course can not have a root element
    // so we check the parent node to set the query selector bindings

    const {
      parentNode
    } = children ? children[0] : el;
    const isTemplateTag = isTemplate(el);
    const templateTagOffset = isTemplateTag ? Math.max(Array.from(parentNode.childNodes).indexOf(el), 0) : null;
    this.isTemplateTag = isTemplateTag; // create the DOM if it wasn't created before

    this.createDOM(el);

    if (this.dom) {
      // create the new template dom fragment if it want already passed in via meta
      this.fragment = fragment || this.dom.cloneNode(true);
    } // store root node
    // notice that for template tags the root note will be the parent tag


    this.el = this.isTemplateTag ? parentNode : el; // create the children array only for the <template> fragments

    this.children = this.isTemplateTag ? children || Array.from(this.fragment.childNodes) : null; // inject the DOM into the el only if a fragment is available

    if (!avoidDOMInjection && this.fragment) injectDOM(el, this.fragment); // create the bindings

    this.bindings = this.bindingsData.map(binding => create$1(this.el, binding, templateTagOffset));
    this.bindings.forEach(b => b.mount(scope, parentScope)); // store the template meta properties

    this.meta = meta;
    return this;
  },

  /**
   * Update the template with fresh data
   * @param   {*} scope - template data
   * @param   {*} parentScope - scope of the parent template tag
   * @returns {TemplateChunk} self
   */
  update(scope, parentScope) {
    this.bindings.forEach(b => b.update(scope, parentScope));
    return this;
  },

  /**
   * Remove the template from the node where it was initially mounted
   * @param   {*} scope - template data
   * @param   {*} parentScope - scope of the parent template tag
   * @param   {boolean|null} mustRemoveRoot - if true remove the root element,
   * if false or undefined clean the root tag content, if null don't touch the DOM
   * @returns {TemplateChunk} self
   */
  unmount(scope, parentScope, mustRemoveRoot) {
    if (this.el) {
      this.bindings.forEach(b => b.unmount(scope, parentScope, mustRemoveRoot));

      switch (true) {
        // pure components should handle the DOM unmount updates by themselves
        case this.el[IS_PURE_SYMBOL]:
          break;
        // <template> tags should be treated a bit differently
        // we need to clear their children only if it's explicitly required by the caller
        // via mustRemoveRoot !== null

        case this.children && mustRemoveRoot !== null:
          clearChildren(this.children);
          break;
        // remove the root node only if the mustRemoveRoot === true

        case mustRemoveRoot === true:
          removeChild(this.el);
          break;
        // otherwise we clean the node children

        case mustRemoveRoot !== null:
          cleanNode(this.el);
          break;
      }

      this.el = null;
    }

    return this;
  },

  /**
   * Clone the template chunk
   * @returns {TemplateChunk} a clone of this object resetting the this.el property
   */
  clone() {
    return Object.assign({}, this, {
      meta: {},
      el: null
    });
  }

});
/**
 * Create a template chunk wiring also the bindings
 * @param   {string|HTMLElement} html - template string
 * @param   {Array} bindings - bindings collection
 * @returns {TemplateChunk} a new TemplateChunk copy
 */

function create(html, bindings) {
  if (bindings === void 0) {
    bindings = [];
  }

  return Object.assign({}, TemplateChunk, {
    html,
    bindingsData: bindings
  });
}

/**
 * Method used to bind expressions to a DOM node
 * @param   {string|HTMLElement} html - your static template html structure
 * @param   {Array} bindings - list of the expressions to bind to update the markup
 * @returns {TemplateChunk} a new TemplateChunk object having the `update`,`mount`, `unmount` and `clone` methods
 *
 * @example
 *
 * riotDOMBindings
 *  .template(
 *   `<div expr0><!----></div><div><p expr1><!----><section expr2></section></p>`,
 *   [
 *     {
 *       selector: '[expr0]',
 *       redundantAttribute: 'expr0',
 *       expressions: [
 *         {
 *           type: expressionTypes.TEXT,
 *           childNodeIndex: 0,
 *           evaluate(scope) {
 *             return scope.time;
 *           },
 *         },
 *       ],
 *     },
 *     {
 *       selector: '[expr1]',
 *       redundantAttribute: 'expr1',
 *       expressions: [
 *         {
 *           type: expressionTypes.TEXT,
 *           childNodeIndex: 0,
 *           evaluate(scope) {
 *             return scope.name;
 *           },
 *         },
 *         {
 *           type: 'attribute',
 *           name: 'style',
 *           evaluate(scope) {
 *             return scope.style;
 *           },
 *         },
 *       ],
 *     },
 *     {
 *       selector: '[expr2]',
 *       redundantAttribute: 'expr2',
 *       type: bindingTypes.IF,
 *       evaluate(scope) {
 *         return scope.isVisible;
 *       },
 *       template: riotDOMBindings.template('hello there'),
 *     },
 *   ]
 * )
 */

var DOMBindings = /*#__PURE__*/Object.freeze({
  __proto__: null,
  template: create,
  createBinding: create$1,
  createExpression: create$4,
  bindingTypes: bindingTypes,
  expressionTypes: expressionTypes
});

function noop() {
  return this;
}
/**
 * Autobind the methods of a source object to itself
 * @param   {Object} source - probably a riot tag instance
 * @param   {Array<string>} methods - list of the methods to autobind
 * @returns {Object} the original object received
 */

function autobindMethods(source, methods) {
  methods.forEach(method => {
    source[method] = source[method].bind(source);
  });
  return source;
}
/**
 * Call the first argument received only if it's a function otherwise return it as it is
 * @param   {*} source - anything
 * @returns {*} anything
 */

function callOrAssign(source) {
  return isFunction(source) ? source.prototype && source.prototype.constructor ? new source() : source() : source;
}

/**
 * Helper function to set an immutable property
 * @param   {Object} source - object where the new property will be set
 * @param   {string} key - object key where the new property will be stored
 * @param   {*} value - value of the new property
 * @param   {Object} options - set the propery overriding the default options
 * @returns {Object} - the original object modified
 */
function defineProperty(source, key, value, options) {
  if (options === void 0) {
    options = {};
  }

  /* eslint-disable fp/no-mutating-methods */
  Object.defineProperty(source, key, Object.assign({
    value,
    enumerable: false,
    writable: false,
    configurable: true
  }, options));
  /* eslint-enable fp/no-mutating-methods */

  return source;
}
/**
 * Define multiple properties on a target object
 * @param   {Object} source - object where the new properties will be set
 * @param   {Object} properties - object containing as key pair the key + value properties
 * @param   {Object} options - set the propery overriding the default options
 * @returns {Object} the original object modified
 */

function defineProperties(source, properties, options) {
  Object.entries(properties).forEach(_ref => {
    let [key, value] = _ref;
    defineProperty(source, key, value, options);
  });
  return source;
}
/**
 * Define default properties if they don't exist on the source object
 * @param   {Object} source - object that will receive the default properties
 * @param   {Object} defaults - object containing additional optional keys
 * @returns {Object} the original object received enhanced
 */

function defineDefaults(source, defaults) {
  Object.entries(defaults).forEach(_ref2 => {
    let [key, value] = _ref2;
    if (!source[key]) source[key] = value;
  });
  return source;
}

/**
 * Converts any DOM node/s to a loopable array
 * @param   { HTMLElement|NodeList } els - single html element or a node list
 * @returns { Array } always a loopable object
 */
function domToArray(els) {
  // can this object be already looped?
  if (!Array.isArray(els)) {
    // is it a node list?
    if (/^\[object (HTMLCollection|NodeList|Object)\]$/.test(Object.prototype.toString.call(els)) && typeof els.length === 'number') return Array.from(els);else // if it's a single node
      // it will be returned as "array" with one single entry
      return [els];
  } // this object could be looped out of the box


  return els;
}

/**
 * Simple helper to find DOM nodes returning them as array like loopable object
 * @param   { string|DOMNodeList } selector - either the query or the DOM nodes to arraify
 * @param   { HTMLElement }        ctx      - context defining where the query will search for the DOM nodes
 * @returns { Array } DOM nodes found as array
 */

function $(selector, ctx) {
  return domToArray(typeof selector === 'string' ? (ctx || document).querySelectorAll(selector) : selector);
}

/**
 * Normalize the return values, in case of a single value we avoid to return an array
 * @param   { Array } values - list of values we want to return
 * @returns { Array|string|boolean } either the whole list of values or the single one found
 * @private
 */

const normalize = values => values.length === 1 ? values[0] : values;
/**
 * Parse all the nodes received to get/remove/check their attributes
 * @param   { HTMLElement|NodeList|Array } els    - DOM node/s to parse
 * @param   { string|Array }               name   - name or list of attributes
 * @param   { string }                     method - method that will be used to parse the attributes
 * @returns { Array|string } result of the parsing in a list or a single value
 * @private
 */


function parseNodes(els, name, method) {
  const names = typeof name === 'string' ? [name] : name;
  return normalize(domToArray(els).map(el => {
    return normalize(names.map(n => el[method](n)));
  }));
}
/**
 * Set any attribute on a single or a list of DOM nodes
 * @param   { HTMLElement|NodeList|Array } els   - DOM node/s to parse
 * @param   { string|Object }              name  - either the name of the attribute to set
 *                                                 or a list of properties as object key - value
 * @param   { string }                     value - the new value of the attribute (optional)
 * @returns { HTMLElement|NodeList|Array } the original array of elements passed to this function
 *
 * @example
 *
 * import { set } from 'bianco.attr'
 *
 * const img = document.createElement('img')
 *
 * set(img, 'width', 100)
 *
 * // or also
 * set(img, {
 *   width: 300,
 *   height: 300
 * })
 *
 */


function set(els, name, value) {
  const attrs = typeof name === 'object' ? name : {
    [name]: value
  };
  const props = Object.keys(attrs);
  domToArray(els).forEach(el => {
    props.forEach(prop => el.setAttribute(prop, attrs[prop]));
  });
  return els;
}
/**
 * Get any attribute from a single or a list of DOM nodes
 * @param   { HTMLElement|NodeList|Array } els   - DOM node/s to parse
 * @param   { string|Array }               name  - name or list of attributes to get
 * @returns { Array|string } list of the attributes found
 *
 * @example
 *
 * import { get } from 'bianco.attr'
 *
 * const img = document.createElement('img')
 *
 * get(img, 'width') // => '200'
 *
 * // or also
 * get(img, ['width', 'height']) // => ['200', '300']
 *
 * // or also
 * get([img1, img2], ['width', 'height']) // => [['200', '300'], ['500', '200']]
 */

function get(els, name) {
  return parseNodes(els, name, 'getAttribute');
}

const CSS_BY_NAME = new Map();
const STYLE_NODE_SELECTOR = 'style[riot]'; // memoized curried function

const getStyleNode = (style => {
  return () => {
    // lazy evaluation:
    // if this function was already called before
    // we return its cached result
    if (style) return style; // create a new style element or use an existing one
    // and cache it internally

    style = $(STYLE_NODE_SELECTOR)[0] || document.createElement('style');
    set(style, 'type', 'text/css');
    /* istanbul ignore next */

    if (!style.parentNode) document.head.appendChild(style);
    return style;
  };
})();
/**
 * Object that will be used to inject and manage the css of every tag instance
 */


var cssManager = {
  CSS_BY_NAME,

  /**
   * Save a tag style to be later injected into DOM
   * @param { string } name - if it's passed we will map the css to a tagname
   * @param { string } css - css string
   * @returns {Object} self
   */
  add(name, css) {
    if (!CSS_BY_NAME.has(name)) {
      CSS_BY_NAME.set(name, css);
      this.inject();
    }

    return this;
  },

  /**
   * Inject all previously saved tag styles into DOM
   * innerHTML seems slow: http://jsperf.com/riot-insert-style
   * @returns {Object} self
   */
  inject() {
    getStyleNode().innerHTML = [...CSS_BY_NAME.values()].join('\n');
    return this;
  },

  /**
   * Remove a tag style from the DOM
   * @param {string} name a registered tagname
   * @returns {Object} self
   */
  remove(name) {
    if (CSS_BY_NAME.has(name)) {
      CSS_BY_NAME.delete(name);
      this.inject();
    }

    return this;
  }

};

/**
 * Function to curry any javascript method
 * @param   {Function}  fn - the target function we want to curry
 * @param   {...[args]} acc - initial arguments
 * @returns {Function|*} it will return a function until the target function
 *                       will receive all of its arguments
 */
function curry(fn) {
  for (var _len = arguments.length, acc = new Array(_len > 1 ? _len - 1 : 0), _key = 1; _key < _len; _key++) {
    acc[_key - 1] = arguments[_key];
  }

  return function () {
    for (var _len2 = arguments.length, args = new Array(_len2), _key2 = 0; _key2 < _len2; _key2++) {
      args[_key2] = arguments[_key2];
    }

    args = [...acc, ...args];
    return args.length < fn.length ? curry(fn, ...args) : fn(...args);
  };
}

/**
 * Get the tag name of any DOM node
 * @param   {HTMLElement} element - DOM node we want to inspect
 * @returns {string} name to identify this dom node in riot
 */

function getName(element) {
  return get(element, IS_DIRECTIVE) || element.tagName.toLowerCase();
}

const COMPONENT_CORE_HELPERS = Object.freeze({
  // component helpers
  $(selector) {
    return $(selector, this.root)[0];
  },

  $$(selector) {
    return $(selector, this.root);
  }

});
const PURE_COMPONENT_API = Object.freeze({
  [MOUNT_METHOD_KEY]: noop,
  [UPDATE_METHOD_KEY]: noop,
  [UNMOUNT_METHOD_KEY]: noop
});
const COMPONENT_LIFECYCLE_METHODS = Object.freeze({
  [SHOULD_UPDATE_KEY]: noop,
  [ON_BEFORE_MOUNT_KEY]: noop,
  [ON_MOUNTED_KEY]: noop,
  [ON_BEFORE_UPDATE_KEY]: noop,
  [ON_UPDATED_KEY]: noop,
  [ON_BEFORE_UNMOUNT_KEY]: noop,
  [ON_UNMOUNTED_KEY]: noop
});
const MOCKED_TEMPLATE_INTERFACE = Object.assign({}, PURE_COMPONENT_API, {
  clone: noop,
  createDOM: noop
});
/**
 * Performance optimization for the recursive components
 * @param  {RiotComponentShell} componentShell - riot compiler generated object
 * @returns {Object} component like interface
 */

const memoizedCreateComponent = memoize(createComponent);
/**
 * Evaluate the component properties either from its real attributes or from its initial user properties
 * @param   {HTMLElement} element - component root
 * @param   {Object}  initialProps - initial props
 * @returns {Object} component props key value pairs
 */

function evaluateInitialProps(element, initialProps) {
  if (initialProps === void 0) {
    initialProps = {};
  }

  return Object.assign({}, DOMattributesToObject(element), callOrAssign(initialProps));
}
/**
 * Bind a DOM node to its component object
 * @param   {HTMLElement} node - html node mounted
 * @param   {Object} component - Riot.js component object
 * @returns {Object} the component object received as second argument
 */


const bindDOMNodeToComponentObject = (node, component) => node[DOM_COMPONENT_INSTANCE_PROPERTY$1] = component;
/**
 * Wrap the Riot.js core API methods using a mapping function
 * @param   {Function} mapFunction - lifting function
 * @returns {Object} an object having the { mount, update, unmount } functions
 */


function createCoreAPIMethods(mapFunction) {
  return [MOUNT_METHOD_KEY, UPDATE_METHOD_KEY, UNMOUNT_METHOD_KEY].reduce((acc, method) => {
    acc[method] = mapFunction(method);
    return acc;
  }, {});
}
/**
 * Factory function to create the component templates only once
 * @param   {Function} template - component template creation function
 * @param   {RiotComponentShell} componentShell - riot compiler generated object
 * @returns {TemplateChunk} template chunk object
 */


function componentTemplateFactory(template, componentShell) {
  const components = createSubcomponents(componentShell.exports ? componentShell.exports.components : {});
  return template(create, expressionTypes, bindingTypes, name => {
    // improve support for recursive components
    if (name === componentShell.name) return memoizedCreateComponent(componentShell); // return the registered components

    return components[name] || COMPONENTS_IMPLEMENTATION_MAP$1.get(name);
  });
}
/**
 * Create a pure component
 * @param   {Function} pureFactoryFunction - pure component factory function
 * @param   {Array} options.slots - component slots
 * @param   {Array} options.attributes - component attributes
 * @param   {Array} options.template - template factory function
 * @param   {Array} options.template - template factory function
 * @param   {any} options.props - initial component properties
 * @returns {Object} pure component object
 */


function createPureComponent(pureFactoryFunction, _ref) {
  let {
    slots,
    attributes,
    props,
    css,
    template
  } = _ref;
  if (template) panic('Pure components can not have html');
  if (css) panic('Pure components do not have css');
  const component = defineDefaults(pureFactoryFunction({
    slots,
    attributes,
    props
  }), PURE_COMPONENT_API);
  return createCoreAPIMethods(method => function () {
    for (var _len = arguments.length, args = new Array(_len), _key = 0; _key < _len; _key++) {
      args[_key] = arguments[_key];
    }

    // intercept the mount calls to bind the DOM node to the pure object created
    // see also https://github.com/riot/riot/issues/2806
    if (method === MOUNT_METHOD_KEY) {
      const [el] = args; // mark this node as pure element

      el[IS_PURE_SYMBOL] = true;
      bindDOMNodeToComponentObject(el, component);
    }

    component[method](...args);
    return component;
  });
}
/**
 * Create the component interface needed for the @riotjs/dom-bindings tag bindings
 * @param   {RiotComponentShell} componentShell - riot compiler generated object
 * @param   {string} componentShell.css - component css
 * @param   {Function} componentShell.template - function that will return the dom-bindings template function
 * @param   {Object} componentShell.exports - component interface
 * @param   {string} componentShell.name - component name
 * @returns {Object} component like interface
 */


function createComponent(componentShell) {
  const {
    css,
    template,
    exports,
    name
  } = componentShell;
  const templateFn = template ? componentTemplateFactory(template, componentShell) : MOCKED_TEMPLATE_INTERFACE;
  return _ref2 => {
    let {
      slots,
      attributes,
      props
    } = _ref2;
    // pure components rendering will be managed by the end user
    if (exports && exports[IS_PURE_SYMBOL]) return createPureComponent(exports, {
      slots,
      attributes,
      props,
      css,
      template
    });
    const componentAPI = callOrAssign(exports) || {};
    const component = defineComponent({
      css,
      template: templateFn,
      componentAPI,
      name
    })({
      slots,
      attributes,
      props
    }); // notice that for the components create via tag binding
    // we need to invert the mount (state/parentScope) arguments
    // the template bindings will only forward the parentScope updates
    // and never deal with the component state

    return {
      mount(element, parentScope, state) {
        return component.mount(element, state, parentScope);
      },

      update(parentScope, state) {
        return component.update(state, parentScope);
      },

      unmount(preserveRoot) {
        return component.unmount(preserveRoot);
      }

    };
  };
}
/**
 * Component definition function
 * @param   {Object} implementation - the componen implementation will be generated via compiler
 * @param   {Object} component - the component initial properties
 * @returns {Object} a new component implementation object
 */

function defineComponent(_ref3) {
  let {
    css,
    template,
    componentAPI,
    name
  } = _ref3;
  // add the component css into the DOM
  if (css && name) cssManager.add(name, css);
  return curry(enhanceComponentAPI)(defineProperties( // set the component defaults without overriding the original component API
  defineDefaults(componentAPI, Object.assign({}, COMPONENT_LIFECYCLE_METHODS, {
    [PROPS_KEY]: {},
    [STATE_KEY]: {}
  })), Object.assign({
    // defined during the component creation
    [SLOTS_KEY]: null,
    [ROOT_KEY]: null
  }, COMPONENT_CORE_HELPERS, {
    name,
    css,
    template
  })));
}
/**
 * Create the bindings to update the component attributes
 * @param   {HTMLElement} node - node where we will bind the expressions
 * @param   {Array} attributes - list of attribute bindings
 * @returns {TemplateChunk} - template bindings object
 */

function createAttributeBindings(node, attributes) {
  if (attributes === void 0) {
    attributes = [];
  }

  const expressions = attributes.map(a => create$4(node, a));
  const binding = {};
  return Object.assign(binding, Object.assign({
    expressions
  }, createCoreAPIMethods(method => scope => {
    expressions.forEach(e => e[method](scope));
    return binding;
  })));
}
/**
 * Create the subcomponents that can be included inside a tag in runtime
 * @param   {Object} components - components imported in runtime
 * @returns {Object} all the components transformed into Riot.Component factory functions
 */


function createSubcomponents(components) {
  if (components === void 0) {
    components = {};
  }

  return Object.entries(callOrAssign(components)).reduce((acc, _ref4) => {
    let [key, value] = _ref4;
    acc[camelToDashCase(key)] = createComponent(value);
    return acc;
  }, {});
}
/**
 * Run the component instance through all the plugins set by the user
 * @param   {Object} component - component instance
 * @returns {Object} the component enhanced by the plugins
 */


function runPlugins(component) {
  return [...PLUGINS_SET$1].reduce((c, fn) => fn(c) || c, component);
}
/**
 * Compute the component current state merging it with its previous state
 * @param   {Object} oldState - previous state object
 * @param   {Object} newState - new state givent to the `update` call
 * @returns {Object} new object state
 */


function computeState(oldState, newState) {
  return Object.assign({}, oldState, callOrAssign(newState));
}
/**
 * Add eventually the "is" attribute to link this DOM node to its css
 * @param {HTMLElement} element - target root node
 * @param {string} name - name of the component mounted
 * @returns {undefined} it's a void function
 */


function addCssHook(element, name) {
  if (getName(element) !== name) {
    set(element, IS_DIRECTIVE, name);
  }
}
/**
 * Component creation factory function that will enhance the user provided API
 * @param   {Object} component - a component implementation previously defined
 * @param   {Array} options.slots - component slots generated via riot compiler
 * @param   {Array} options.attributes - attribute expressions generated via riot compiler
 * @returns {Riot.Component} a riot component instance
 */


function enhanceComponentAPI(component, _ref5) {
  let {
    slots,
    attributes,
    props
  } = _ref5;
  return autobindMethods(runPlugins(defineProperties(isObject(component) ? Object.create(component) : component, {
    mount(element, state, parentScope) {
      if (state === void 0) {
        state = {};
      }

      this[ATTRIBUTES_KEY_SYMBOL] = createAttributeBindings(element, attributes).mount(parentScope);
      defineProperty(this, PROPS_KEY, Object.freeze(Object.assign({}, evaluateInitialProps(element, props), evaluateAttributeExpressions(this[ATTRIBUTES_KEY_SYMBOL].expressions))));
      this[STATE_KEY] = computeState(this[STATE_KEY], state);
      this[TEMPLATE_KEY_SYMBOL] = this.template.createDOM(element).clone(); // link this object to the DOM node

      bindDOMNodeToComponentObject(element, this); // add eventually the 'is' attribute

      component.name && addCssHook(element, component.name); // define the root element

      defineProperty(this, ROOT_KEY, element); // define the slots array

      defineProperty(this, SLOTS_KEY, slots); // before mount lifecycle event

      this[ON_BEFORE_MOUNT_KEY](this[PROPS_KEY], this[STATE_KEY]);
      this[PARENT_KEY_SYMBOL] = parentScope; // mount the template

      this[TEMPLATE_KEY_SYMBOL].mount(element, this, parentScope);
      this[ON_MOUNTED_KEY](this[PROPS_KEY], this[STATE_KEY]);
      return this;
    },

    update(state, parentScope) {
      if (state === void 0) {
        state = {};
      }

      if (parentScope) {
        this[PARENT_KEY_SYMBOL] = parentScope;
        this[ATTRIBUTES_KEY_SYMBOL].update(parentScope);
      }

      const newProps = evaluateAttributeExpressions(this[ATTRIBUTES_KEY_SYMBOL].expressions);
      if (this[SHOULD_UPDATE_KEY](newProps, this[PROPS_KEY]) === false) return;
      defineProperty(this, PROPS_KEY, Object.freeze(Object.assign({}, this[PROPS_KEY], newProps)));
      this[STATE_KEY] = computeState(this[STATE_KEY], state);
      this[ON_BEFORE_UPDATE_KEY](this[PROPS_KEY], this[STATE_KEY]); // avoiding recursive updates
      // see also https://github.com/riot/riot/issues/2895

      if (!this[IS_COMPONENT_UPDATING]) {
        this[IS_COMPONENT_UPDATING] = true;
        this[TEMPLATE_KEY_SYMBOL].update(this, this[PARENT_KEY_SYMBOL]);
      }

      this[ON_UPDATED_KEY](this[PROPS_KEY], this[STATE_KEY]);
      this[IS_COMPONENT_UPDATING] = false;
      return this;
    },

    unmount(preserveRoot) {
      this[ON_BEFORE_UNMOUNT_KEY](this[PROPS_KEY], this[STATE_KEY]);
      this[ATTRIBUTES_KEY_SYMBOL].unmount(); // if the preserveRoot is null the template html will be left untouched
      // in that case the DOM cleanup will happen differently from a parent node

      this[TEMPLATE_KEY_SYMBOL].unmount(this, this[PARENT_KEY_SYMBOL], preserveRoot === null ? null : !preserveRoot);
      this[ON_UNMOUNTED_KEY](this[PROPS_KEY], this[STATE_KEY]);
      return this;
    }

  })), Object.keys(component).filter(prop => isFunction(component[prop])));
}
/**
 * Component initialization function starting from a DOM node
 * @param   {HTMLElement} element - element to upgrade
 * @param   {Object} initialProps - initial component properties
 * @param   {string} componentName - component id
 * @returns {Object} a new component instance bound to a DOM node
 */

function mountComponent(element, initialProps, componentName) {
  const name = componentName || getName(element);
  if (!COMPONENTS_IMPLEMENTATION_MAP$1.has(name)) panic(`The component named "${name}" was never registered`);
  const component = COMPONENTS_IMPLEMENTATION_MAP$1.get(name)({
    props: initialProps
  });
  return component.mount(element);
}

/**
 * Similar to compose but performs from left-to-right function composition.<br/>
 * {@link https://30secondsofcode.org/function#composeright see also}
 * @param   {...[function]} fns) - list of unary function
 * @returns {*} result of the computation
 */
/**
 * Performs right-to-left function composition.<br/>
 * Use Array.prototype.reduce() to perform right-to-left function composition.<br/>
 * The last (rightmost) function can accept one or more arguments; the remaining functions must be unary.<br/>
 * {@link https://30secondsofcode.org/function#compose original source code}
 * @param   {...[function]} fns) - list of unary function
 * @returns {*} result of the computation
 */

function compose() {
  for (var _len2 = arguments.length, fns = new Array(_len2), _key2 = 0; _key2 < _len2; _key2++) {
    fns[_key2] = arguments[_key2];
  }

  return fns.reduce((f, g) => function () {
    return f(g(...arguments));
  });
}

const {
  DOM_COMPONENT_INSTANCE_PROPERTY,
  COMPONENTS_IMPLEMENTATION_MAP,
  PLUGINS_SET
} = globals;
/**
 * Riot public api
 */

/**
 * Register a custom tag by name
 * @param   {string} name - component name
 * @param   {Object} implementation - tag implementation
 * @returns {Map} map containing all the components implementations
 */

function register(name, _ref) {
  let {
    css,
    template,
    exports
  } = _ref;
  if (COMPONENTS_IMPLEMENTATION_MAP.has(name)) panic(`The component "${name}" was already registered`);
  COMPONENTS_IMPLEMENTATION_MAP.set(name, createComponent({
    name,
    css,
    template,
    exports
  }));
  return COMPONENTS_IMPLEMENTATION_MAP;
}
/**
 * Unregister a riot web component
 * @param   {string} name - component name
 * @returns {Map} map containing all the components implementations
 */

function unregister(name) {
  if (!COMPONENTS_IMPLEMENTATION_MAP.has(name)) panic(`The component "${name}" was never registered`);
  COMPONENTS_IMPLEMENTATION_MAP.delete(name);
  cssManager.remove(name);
  return COMPONENTS_IMPLEMENTATION_MAP;
}
/**
 * Mounting function that will work only for the components that were globally registered
 * @param   {string|HTMLElement} selector - query for the selection or a DOM element
 * @param   {Object} initialProps - the initial component properties
 * @param   {string} name - optional component name
 * @returns {Array} list of nodes upgraded
 */

function mount(selector, initialProps, name) {
  return $(selector).map(element => mountComponent(element, initialProps, name));
}
/**
 * Sweet unmounting helper function for the DOM node mounted manually by the user
 * @param   {string|HTMLElement} selector - query for the selection or a DOM element
 * @param   {boolean|null} keepRootElement - if true keep the root element
 * @returns {Array} list of nodes unmounted
 */

function unmount(selector, keepRootElement) {
  return $(selector).map(element => {
    if (element[DOM_COMPONENT_INSTANCE_PROPERTY]) {
      element[DOM_COMPONENT_INSTANCE_PROPERTY].unmount(keepRootElement);
    }

    return element;
  });
}
/**
 * Define a riot plugin
 * @param   {Function} plugin - function that will receive all the components created
 * @returns {Set} the set containing all the plugins installed
 */

function install(plugin) {
  if (!isFunction(plugin)) panic('Plugins must be of type function');
  if (PLUGINS_SET.has(plugin)) panic('This plugin was already installed');
  PLUGINS_SET.add(plugin);
  return PLUGINS_SET;
}
/**
 * Uninstall a riot plugin
 * @param   {Function} plugin - plugin previously installed
 * @returns {Set} the set containing all the plugins installed
 */

function uninstall(plugin) {
  if (!PLUGINS_SET.has(plugin)) panic('This plugin was never installed');
  PLUGINS_SET.delete(plugin);
  return PLUGINS_SET;
}
/**
 * Helper method to create component without relying on the registered ones
 * @param   {Object} implementation - component implementation
 * @returns {Function} function that will allow you to mount a riot component on a DOM node
 */

function component(implementation) {
  return function (el, props, _temp) {
    let {
      slots,
      attributes,
      parentScope
    } = _temp === void 0 ? {} : _temp;
    return compose(c => c.mount(el, parentScope), c => c({
      props,
      slots,
      attributes
    }), createComponent)(implementation);
  };
}
/**
 * Lift a riot component Interface into a pure riot object
 * @param   {Function} func - RiotPureComponent factory function
 * @returns {Function} the lifted original function received as argument
 */

function pure(func) {
  if (!isFunction(func)) panic('riot.pure accepts only arguments of type "function"');
  func[IS_PURE_SYMBOL] = true;
  return func;
}
/** @type {string} current riot version */

const version = 'v5.4.1'; // expose some internal stuff that might be used from external tools

const __ = {
  cssManager,
  DOMBindings,
  createComponent,
  defineComponent,
  globals
};

export { __, component, install, mount, pure, register, uninstall, unmount, unregister, version };