rewrite using IoC and DI

model/lyric.go

@@ -0,0 +1,84 @@
+package model
+
+import (
+	"github.com/spf13/cast"
+	"regexp"
+	"sort"
+	"strings"
+)
+
+var timeTagRegex = regexp.MustCompile("\\[[0-9]+:[0-9]+(\\.[0-9]+)?\\]")
+
+type LyricLine struct {
+	Time        float64 // in seconds
+	Lyric       string
+	Translation string
+}
+
+type LyricContext struct {
+	Current *LyricLine
+	Prev    []*LyricLine
+	Next    []*LyricLine
+}
+
+type Lyric struct {
+	Lyrics []*LyricLine
+}
+
+func LoadLyric(lyric string) *Lyric {
+	tmp := make(map[float64]*LyricLine)
+	times := make([]float64, 0)
+	for _, line := range strings.Split(lyric, "\n") {
+		lrc := timeTagRegex.ReplaceAllString(line, "")
+		for _, time := range timeTagRegex.FindAllString(line, -1) {
+			ts := strings.Split(time[1:len(time)-1], ":")
+			t := cast.ToFloat64(ts[0])*60 + cast.ToFloat64(ts[1])
+			times = append(times, t)
+			tmp[t] = &LyricLine{
+				Time:  t,
+				Lyric: lrc,
+			}
+		}
+	}
+	sort.Float64s(times)
+	lrcs := make([]*LyricLine, len(times))
+	for index, time := range times {
+		lrcs[index] = tmp[time]
+	}
+	if len(lrcs) == 0 {
+		lrcs = append(lrcs, &LyricLine{Time: 0, Lyric: ""})
+	}
+	lrcs = append(lrcs, &LyricLine{
+		Time:  99999999999,
+		Lyric: "",
+	})
+	return &Lyric{Lyrics: lrcs}
+}
+
+func (l *Lyric) Find(time float64) *LyricLine {
+	for i := 0; i < len(l.Lyrics)-1; i++ {
+		if l.Lyrics[i].Time <= time && time < l.Lyrics[i+1].Time {
+			return l.Lyrics[i]
+		}
+	}
+	return nil
+}
+
+func (l *Lyric) FindContext(time float64, prev int, next int) *LyricContext {
+	for i := 0; i < len(l.Lyrics)-1; i++ {
+		if l.Lyrics[i].Time <= time && time < l.Lyrics[i+1].Time {
+			if (i + prev) < 0 {
+				prev = -i
+			}
+			if (i + 1 + next) > len(l.Lyrics) {
+				next = len(l.Lyrics) - i - 1
+			}
+			return &LyricContext{
+				Current: l.Lyrics[i],
+				Prev:    l.Lyrics[i+prev : i],
+				Next:    l.Lyrics[i+1 : i+1+next],
+			}
+		}
+	}
+	return nil
+}