package app

import (
	"context"
	"fmt"
	"sort"
	"strconv"
	"strings"
	"time"

	"cnb.cool/looc/git-cnb/git"
	ui "cnb.cool/looc/git-cnb/ui"
	"github.com/spf13/cobra"
)

type Week struct {
	Week    int64
	Commits int
}

type User struct {
	User    string
	Commits int
}

var StatsCmd = &cobra.Command{
	Use:   "stats",
	Short: "print stats information of this repo",
	Long:  "print stats information of this repo",
	Run: func(cmd *cobra.Command, args []string) {
		Stats(cmd.Context())
	},
}

func Stats(ctx context.Context) {
	lines, err := git.GetCommits()
	if err != nil {
		ui.ErrorWithExit(err.Error())
	}

	todayWeek := getStartOfWeek(time.Now())
	weeklyMap := generateLastWeeks(todayWeek, 80)
	userMap := make(map[string]int)
	for _, v := range lines {
		s := strings.Split(v, ";")
		timeStr := s[0]
		userStr := s[1]
		userMap[strings.Trim(userStr, "'")]++
		timestamp, err := strconv.ParseInt(strings.Trim(timeStr, "'"), 10, 64)
		if err != nil {
			ui.Error(err.Error())
			continue
		}
		weekKey := getStartOfWeek(time.Unix(timestamp, 0))
		if _, ok := weeklyMap[weekKey]; !ok {
			continue
		}
		weeklyMap[weekKey]++
	}
	ui.InitDashBoard()
	drawUserRanking(userMap)
	drawCommitTrendLine(weeklyMap)
	ui.DrawDashBoard()
}

// 获取自然周的第一天（周一）
func getStartOfWeek(t time.Time) int64 {
	weekday := t.Weekday()
	if weekday == time.Sunday {
		weekday = 7
	}
	w := fmt.Sprintf("%s 00:00:00",
		t.AddDate(0, 0, -int(weekday)+1).Format("2006-01-02"))

	dt, _ := time.Parse("2006-01-02 15:04:05", w)
	return dt.Unix()
}

func generateLastWeeks(unixTimestamp int64, limit int) map[int64]int {
	var t time.Time
	t = time.Unix(unixTimestamp, 0)
	m := make(map[int64]int)
	for i := 0; i < limit; i++ {
		m[t.Unix()] = 0
		t = t.AddDate(0, 0, -7)
	}
	return m
}

func drawUserRanking(userMap map[string]int) {
	userList := make([]User, 0, len(userMap))
	for k, v := range userMap {
		userList = append(userList, User{
			User:    k,
			Commits: v,
		})
	}
	sort.Slice(userList, func(i, j int) bool {
		return userList[i].Commits > userList[j].Commits
	})

	count := len(userList)
	if count > 13 {
		count = 13
	}
	list := make([]string, 0, count)
	for _, v := range userList[:count] {
		item := fmt.Sprintf("[%d] %s", v.Commits, v.User)
		list = append(list, item)
	}
	position := ui.Position{
		X:      0,
		Y:      0,
		Width:  30,
		Height: 15,
	}
	ui.ListChart("历史提交榜", position, list)
}
func drawCommitTrendLine(weeklyMap map[int64]int) {
	list := make([]Week, 0, len(weeklyMap))
	for k, v := range weeklyMap {
		list = append(list, Week{
			Week:    k,
			Commits: v,
		})
	}
	sort.Slice(list, func(i, j int) bool {
		return list[i].Week < list[j].Week
	})
	data := make([]float64, 0, len(weeklyMap))
	for _, v := range list {
		data = append(data, float64(v.Commits))
	}
	position := ui.Position{
		X:      30,
		Y:      0,
		Width:  120,
		Height: 15,
	}
	ui.LineChart("过去 80 周的提交曲线", position, data)
}