package server

import (
	"context"
	"encoding/json"
	"log"
	"time"

	"git.zb-server.de/ZB-Server/EscapeFromTeacher/pkg/game"
	"github.com/redis/go-redis/v9"
)

type Leaderboard struct {
	rdb *redis.Client
	ctx context.Context
}

var GlobalLeaderboard *Leaderboard

const leaderboardKey = "leaderboard:top"

func InitLeaderboard(redisAddr string) error {
	rdb := redis.NewClient(&redis.Options{
		Addr: redisAddr,
		DB:   0,
	})

	ctx := context.Background()
	if err := rdb.Ping(ctx).Err(); err != nil {
		return err
	}

	GlobalLeaderboard = &Leaderboard{
		rdb: rdb,
		ctx: ctx,
	}

	log.Println("📊 Redis-Leaderboard verbunden")
	return nil
}

func (lb *Leaderboard) AddScore(name, code string, score int) bool {
	// Prüfe ob Spieler bereits existiert
	existingScoreStr, err := lb.rdb.HGet(lb.ctx, "leaderboard:players", code).Result()
	if err == nil {
		var existingScore int
		json.Unmarshal([]byte(existingScoreStr), &existingScore)
		if score <= existingScore {
			return false // Neuer Score nicht besser
		}
	}

	// Score speichern
	entry := game.LeaderboardEntry{
		PlayerName: name,
		PlayerCode: code,
		Score:      score,
		Timestamp:  time.Now().Unix(),
	}

	data, _ := json.Marshal(entry)
	lb.rdb.HSet(lb.ctx, "leaderboard:players", code, string(data))

	// In Sorted Set mit Score als Wert
	lb.rdb.ZAdd(lb.ctx, leaderboardKey, redis.Z{
		Score:  float64(score),
		Member: code,
	})

	log.Printf("🏆 Leaderboard Update: %s mit %d Punkten", name, score)
	return true
}

func (lb *Leaderboard) GetTop10() []game.LeaderboardEntry {
	// Hole Top 10 (höchste Scores zuerst)
	codes, err := lb.rdb.ZRevRange(lb.ctx, leaderboardKey, 0, 9).Result()
	if err != nil {
		log.Printf("⚠️ Fehler beim Abrufen des Leaderboards: %v", err)
		return []game.LeaderboardEntry{}
	}

	entries := make([]game.LeaderboardEntry, 0)
	for _, code := range codes {
		dataStr, err := lb.rdb.HGet(lb.ctx, "leaderboard:players", code).Result()
		if err != nil {
			continue
		}

		var entry game.LeaderboardEntry
		if err := json.Unmarshal([]byte(dataStr), &entry); err != nil {
			continue
		}
		entries = append(entries, entry)
	}

	return entries
}