package commands

import (
	"bytes"
	"time"

	"git.anhgelus.world/anhgelus/les-copaings-bot/config"
	"git.anhgelus.world/anhgelus/les-copaings-bot/exp"
	"git.anhgelus.world/anhgelus/les-copaings-bot/user"
	"github.com/anhgelus/gokord"
	"github.com/anhgelus/gokord/cmd"
	"github.com/anhgelus/gokord/logger"
	"github.com/bwmarrin/discordgo"
	"github.com/jackc/pgx/v5/pgtype"
	"gonum.org/v1/plot"
	"gonum.org/v1/plot/plotter"
	"gonum.org/v1/plot/plotutil"
	"gonum.org/v1/plot/vg"
)

type data struct {
	CreatedAt *pgtype.Date
	XP        int
	CopaingID int
}

func Stats(s *discordgo.Session, i *discordgo.InteractionCreate, opt cmd.OptionMap, resp *cmd.ResponseBuilder) {
	cfg := config.GetGuildConfig(i.GuildID)
	days := cfg.DaysXPRemains
	if v, ok := opt["days"]; ok {
		in := v.IntValue()
		if in < 0 || uint(in) > days {
			if err := resp.SetMessage("Nombre de jours invalide").IsEphemeral().Send(); err != nil {
				logger.Alert("commands/stats.go - Sending invalid days", err.Error())
			}
			return
		}
		days = uint(in)
	}
	var rawData []*data
	res := gokord.DB.Raw(
		`SELECT "created_at"::date::text, sum("xp") as xp, "copaing_id" FROM copaing_xps WHERE "guild_id" = ? and "created_at" > ? GROUP BY "created_at"::date, "copaing_id"`,
		i.GuildID, exp.TimeStampNDaysBefore(days),
	)
	if err := res.Scan(&rawData).Error; err != nil {
		logger.Alert("commands/stats.go - Fetching result", err.Error())
		return
	}

	copaings := map[int]*user.Copaing{}
	stats := map[int]*[]plotter.XY{}

	for _, raw := range rawData {
		_, ok := copaings[raw.CopaingID]
		if !ok {
			var cp user.Copaing
			if err := gokord.DB.First(&cp, raw.CopaingID).Error; err != nil {
				logger.Alert("commands/stats.go - Finding copaing", err.Error(), "id", raw.CopaingID)
				return
			}
			copaings[raw.CopaingID] = &cp
		}
		pts, ok := stats[raw.CopaingID]
		if !ok {
			pts = &[]plotter.XY{}
			stats[raw.CopaingID] = pts
		}
		t := float64(raw.CreatedAt.Time.Unix()-time.Now().Unix()) / (24 * 60 * 60)
		*pts = append(*pts, plotter.XY{
			X: t,
			Y: float64(raw.XP),
		})
	}

	p := plot.New()
	p.Title.Text = "Évolution de l'XP"
	p.X.Label.Text = "Jours"
	p.Y.Label.Text = "XP"

	for in, c := range copaings {
		m, err := s.GuildMember(i.GuildID, c.DiscordID)
		if err != nil {
			logger.Alert("commands/stats.go - Fetching guild member", err.Error())
			return
		}
		err = plotutil.AddLinePoints(p, m.DisplayName(), plotter.XYs(*stats[in]))
		if err != nil {
			logger.Alert("commands/stats.go - Adding line points", err.Error())
			return
		}
	}
	w, err := p.WriterTo(4*vg.Inch, 4*vg.Inch, "png")
	if err != nil {
		logger.Alert("commands/stats.go - Generating png", err.Error())
		return
	}
	b := new(bytes.Buffer)
	_, err = w.WriteTo(b)
	if err != nil {
		logger.Alert("commands/stats.go - Writing png", err.Error())
	}
	err = resp.AddFile(&discordgo.File{
		Name:        "plot.png",
		ContentType: "image/png",
		Reader:      b,
	}).Send()
	if err != nil {
		logger.Alert("commands/stats.go - Sending response", err.Error())
	}
}