Add andreis solution (gophercises#7)

students/andreis/main.go

@@ -0,0 +1,137 @@
+package main
+
+import (
+	"bufio"
+	"context"
+	"encoding/csv"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/fatih/color"
+)
+
+const timeToAnswer = 5 * time.Second
+
+type quiz struct {
+	challenge, response string
+}
+
+func (q *quiz) ask(timeout time.Duration, lines <-chan string, roundOver chan<- struct{}) bool {
+	color.Set(color.FgGreen)
+	fmt.Print("> ")
+	color.Unset()
+	fmt.Println(q.challenge)
+
+	select {
+	case line := <-lines:
+		return clean(line) == clean(q.response)
+	case <-time.After(timeout):
+		color.Set(color.FgRed)
+		fmt.Println("Out of time")
+		color.Unset()
+
+		roundOver <- struct{}{}
+
+		return false
+	}
+}
+
+func main() {
+	if len(os.Args) != 2 {
+		fmt.Println(`USAGE: go run main.go <CSV_FILE>`)
+		fmt.Println(len(os.Args))
+		return
+	}
+
+	qs, err := readCSV(os.Args[1])
+	if err != nil {
+		fmt.Printf("Failed to read file %s: %v\n", os.Args[1], err)
+		return
+	}
+
+	lines := make(chan string)
+	roundOver := make(chan struct{})
+	ctx, cancel := context.WithTimeout(context.Background(), timeToAnswer*time.Duration(len(qs)))
+
+	go listenForUserInput(ctx, bufio.NewReader(os.Stdin), lines, roundOver)
+
+	good := 0
+	for _, q := range qs {
+		if q.ask(timeToAnswer, lines, roundOver) {
+			good++
+		}
+	}
+
+	cancel()
+
+	fmt.Printf("Answered %d/%d questions.\n", good, len(qs))
+}
+
+func clean(a string) string {
+	return strings.TrimSpace(strings.ToLower(a))
+}
+
+func listenForUserInput(ctx context.Context, r io.RuneReader, lines chan<- string, roundOver <-chan struct{}) {
+	inputRunes := []rune{}
+	newline := false
+
+	for {
+		select {
+		case <-ctx.Done():
+			close(lines)
+			return
+		case <-roundOver:
+			inputRunes = inputRunes[:0]
+			newline = false
+		default:
+			if newline {
+				lines <- string(inputRunes)
+				inputRunes = inputRunes[:0]
+				newline = false
+			}
+
+			run, _, err := r.ReadRune()
+			if err != nil {
+				log.Fatalln("Couldn't read rune:", err)
+			}
+
+			if run == '\n' {
+				newline = true
+			} else {
+				inputRunes = append(inputRunes, run)
+			}
+		}
+	}
+}
+
+func readCSV(filename string) ([]quiz, error) {
+	f, err := os.Open(filename)
+	if err != nil {
+		return nil, fmt.Errorf("couldn't open file: %v", err)
+	}
+	defer f.Close() // nolint
+
+	r := csv.NewReader(f)
+	out := []quiz{}
+
+	for {
+		record, err := r.Read()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return nil, fmt.Errorf("error while reading CSV record: %v", err)
+		}
+		if len(record) != 2 {
+			return nil, fmt.Errorf("unexpected number of fields for record: %v", record)
+		}
+
+		out = append(out, quiz{record[0], record[1]})
+	}
+
+	return out, nil
+}