Telegram Webhookによるボット操作機能を追加（課題の追加・完了・一覧・スヌーズ対応）

internal/service/date_parser.go

@@ -0,0 +1,169 @@
+package service
+
+import (
+	"fmt"
+	"regexp"
+	"strconv"
+	"strings"
+	"time"
+)
+
+var (
+	reTimeHHMM  = regexp.MustCompile(`^(\d{1,2}):(\d{2})$`)
+	reTimeHHJMM = regexp.MustCompile(`^(\d{1,2})時(\d{1,2})分$`)
+	reTimeHHJ   = regexp.MustCompile(`^(\d{1,2})時$`)
+	reDateMD    = regexp.MustCompile(`^(\d{1,2})/(\d{1,2})$`)
+	reDateMJDJ  = regexp.MustCompile(`^(\d{1,2})月(\d{1,2})日$`)
+)
+
+var weekdayNames = map[string]time.Weekday{
+	"月": time.Monday,
+	"火": time.Tuesday,
+	"水": time.Wednesday,
+	"木": time.Thursday,
+	"金": time.Friday,
+	"土": time.Saturday,
+	"日": time.Sunday,
+}
+
+// ParseAddCommand parses the arguments after /add.
+// Format: <title> <date> [time] [#subject] [!priority]
+// Returns title, dueDate, subject, priority (Go string: "high"/"medium"/"low"), error.
+// On format error, err.Error() == "usage" means show usage hint.
+func ParseAddCommand(text string) (title string, dueDate time.Time, subject string, priority string, err error) {
+	priority = "medium"
+	tokens := strings.Fields(text)
+	if len(tokens) == 0 {
+		err = fmt.Errorf("usage")
+		return
+	}
+
+	// Extract #subject and !priority modifiers
+	var core []string
+	for _, tok := range tokens {
+		switch {
+		case strings.HasPrefix(tok, "#") && len(tok) > 1:
+			subject = tok[1:]
+		case strings.HasPrefix(tok, "!") && len(tok) > 1:
+			priority = parsePriorityJP(tok[1:])
+		default:
+			core = append(core, tok)
+		}
+	}
+
+	if len(core) < 2 {
+		err = fmt.Errorf("usage")
+		return
+	}
+
+	// Extract optional time token from end
+	hour, minute := 23, 59
+	if h, m, ok := parseTimeToken(core[len(core)-1]); ok {
+		hour, minute = h, m
+		core = core[:len(core)-1]
+	}
+
+	if len(core) < 2 {
+		err = fmt.Errorf("usage")
+		return
+	}
+
+	// Extract date token from end
+	dateTok := core[len(core)-1]
+	parsedDate, ok := parseDateToken(dateTok, hour, minute)
+	if !ok {
+		err = fmt.Errorf("日付が読み取れませんでした: %q\n使える形式: 今日/明日/明後日/月〜日/MM/DD/M月D日", dateTok)
+		return
+	}
+	dueDate = parsedDate
+	core = core[:len(core)-1]
+
+	if len(core) == 0 {
+		err = fmt.Errorf("usage")
+		return
+	}
+	title = strings.Join(core, " ")
+	return
+}
+
+func parsePriorityJP(s string) string {
+	switch s {
+	case "高":
+		return "high"
+	case "低":
+		return "low"
+	default:
+		return "medium"
+	}
+}
+
+func parseTimeToken(s string) (hour, minute int, ok bool) {
+	if m := reTimeHHMM.FindStringSubmatch(s); m != nil {
+		h, _ := strconv.Atoi(m[1])
+		min, _ := strconv.Atoi(m[2])
+		if h <= 23 && min <= 59 {
+			return h, min, true
+		}
+	}
+	if m := reTimeHHJMM.FindStringSubmatch(s); m != nil {
+		h, _ := strconv.Atoi(m[1])
+		min, _ := strconv.Atoi(m[2])
+		if h <= 23 && min <= 59 {
+			return h, min, true
+		}
+	}
+	if m := reTimeHHJ.FindStringSubmatch(s); m != nil {
+		h, _ := strconv.Atoi(m[1])
+		if h <= 23 {
+			return h, 0, true
+		}
+	}
+	return 0, 0, false
+}
+
+func parseDateToken(s string, hour, minute int) (time.Time, bool) {
+	now := time.Now()
+	loc := now.Location()
+
+	switch s {
+	case "今日":
+		return time.Date(now.Year(), now.Month(), now.Day(), hour, minute, 0, 0, loc), true
+	case "明日":
+		d := now.AddDate(0, 0, 1)
+		return time.Date(d.Year(), d.Month(), d.Day(), hour, minute, 0, 0, loc), true
+	case "明後日":
+		d := now.AddDate(0, 0, 2)
+		return time.Date(d.Year(), d.Month(), d.Day(), hour, minute, 0, 0, loc), true
+	}
+
+	if wd, ok := weekdayNames[s]; ok {
+		d := nextWeekdayFrom(now, wd)
+		return time.Date(d.Year(), d.Month(), d.Day(), hour, minute, 0, 0, loc), true
+	}
+
+	var month, day int
+	if m := reDateMD.FindStringSubmatch(s); m != nil {
+		month, _ = strconv.Atoi(m[1])
+		day, _ = strconv.Atoi(m[2])
+	} else if m := reDateMJDJ.FindStringSubmatch(s); m != nil {
+		month, _ = strconv.Atoi(m[1])
+		day, _ = strconv.Atoi(m[2])
+	} else {
+		return time.Time{}, false
+	}
+
+	if month < 1 || month > 12 || day < 1 || day > 31 {
+		return time.Time{}, false
+	}
+	t := time.Date(now.Year(), time.Month(month), day, hour, minute, 0, 0, loc)
+	if t.Before(now) {
+		t = t.AddDate(1, 0, 0)
+	}
+	return t, true
+}
+
+// nextWeekdayFrom returns the date of the next occurrence of wd from 'from'.
+func nextWeekdayFrom(from time.Time, wd time.Weekday) time.Time {
+	days := (int(wd) - int(from.Weekday()) + 7) % 7
+	return from.AddDate(0, 0, days)
+}