package level

import (
	"fmt"
	"sort"
	"time"

	"github.com/bwmarrin/discordgo"

	"gitea.teamortix.com/chanbakjsd/Milen/db"
	"gitea.teamortix.com/chanbakjsd/Milen/persistent"
	"gitea.teamortix.com/chanbakjsd/Milen/util"
)

func RecalculateEverything(dg *discordgo.Session, guildID string) {
	ShouldListen = false
	defer func() {
		ShouldListen = true
	}()

	startTime := time.Now()
	guild, err := dg.Guild(guildID)
	if err != nil {
		util.ReportError(dg, err)
		return
	}
	listOfMessages := make(map[string][]*discordgo.Message)
	latestMessage := make(map[string]string)
	for {
		newMessagesFound := false
		for _, v := range guild.Channels {
			if persistent.IgnoredChannels[v.ID] {
				continue
			}
			beforeID := ""
			for {
				messages, err := dg.ChannelMessages(v.ID, 100, beforeID, "", "")
				if err != nil {
					util.ReportError(dg, err)
					return
				}
				dupe := false
				for _, msg := range messages {
					if msg.ID == latestMessage[v.ID] {
						dupe = true
						break
					}
					if list, ok := listOfMessages[msg.Author.ID]; ok {
						listOfMessages[msg.Author.ID] = append(list, msg)
					} else {
						listOfMessages[msg.Author.ID] = []*discordgo.Message{msg}
					}
				}
				if beforeID == "" && len(messages) > 0 && messages[0].ID != latestMessage[v.ID] {
					newMessagesFound = true
					latestMessage[v.ID] = messages[0].ID
				}
				if len(messages) < 100 || dupe {
					break
				}
				beforeID = messages[99].ID
			}
		}
		fmt.Printf("[RECALC] Batch step reached in %v.\n", time.Now().Sub(startTime))
		if !newMessagesFound {
			break
		}
	}
	fetchedTime := time.Now()
	totalXP := make(map[string]int64)
	for k, v := range listOfMessages {
		sort.Slice(v, func(i, j int) bool {
			return v[i].ID < v[j].ID
		})
		prevTime, err := discordgo.SnowflakeTimestamp(v[0].ID)
		if err != nil {
			util.ReportError(dg, err)
			return
		}
		for i := 1; i < len(v); i++ {
			nextTime, err := discordgo.SnowflakeTimestamp(v[i].ID)
			if err != nil {
				util.ReportError(dg, err)
				return
			}
			xp := int64(nextTime.Sub(prevTime).Seconds())
			if xp > int64(len(v[i].Content)-3)/3 {
				xp = int64(len(v[i].Content)-3) / 3
			}
			if xp > 10 {
				xp = 10
			}
			if xp >= 0 {
				totalXP[k] += xp
			}
			prevTime = nextTime
		}
	}

	processTime := time.Now()
	db.DeleteAllLevel()
	for k, v := range totalXP {
		userHistory := listOfMessages[k]
		newestMessage := userHistory[len(userHistory)-1]
		time, err := discordgo.SnowflakeTimestamp(newestMessage.ID)
		if err != nil {
			util.ReportError(dg, err)
			return
		}
		db.SetXP(k, time, v)
	}

	finishTime := time.Now()

	fmt.Printf("[RECALC] Fetch took %v.\n", fetchedTime.Sub(startTime))
	fmt.Printf("[RECALC] XP calculation took %v.\n", processTime.Sub(fetchedTime))
	fmt.Printf("[RECALC] DB write took %v.\n", finishTime.Sub(processTime))
	fmt.Printf("[RECALC] Total took %v.\n", finishTime.Sub(startTime))
}