package world

import (
	"fmt"
	"sync"

	"eq2emu/internal/achievements"
	"eq2emu/internal/database"
)

// AchievementManager manages achievements for the world server
type AchievementManager struct {
	masterList     *achievements.MasterList
	playerManagers map[int32]*achievements.PlayerManager // CharacterID -> PlayerManager
	database       *database.Database
	world          *World // Reference to world server for notifications

	mutex sync.RWMutex
}

// NewAchievementManager creates a new achievement manager
func NewAchievementManager(db *database.Database) *AchievementManager {
	return &AchievementManager{
		masterList:     achievements.NewMasterList(),
		playerManagers: make(map[int32]*achievements.PlayerManager),
		database:       db,
		world:          nil, // Set by world server after creation
	}
}

// SetWorld sets the world server reference for notifications
func (am *AchievementManager) SetWorld(world *World) {
	am.world = world
}

// LoadAchievements loads all achievements from database
func (am *AchievementManager) LoadAchievements() error {
	fmt.Println("Loading master achievement list...")

	err := achievements.LoadAllAchievements(am.database, am.masterList)
	if err != nil {
		return fmt.Errorf("failed to load achievements: %w", err)
	}

	fmt.Printf("Loaded %d achievements\n", am.masterList.Size())
	return nil
}

// GetPlayerManager gets or creates a player achievement manager
func (am *AchievementManager) GetPlayerManager(characterID int32) *achievements.PlayerManager {
	am.mutex.RLock()
	playerMgr, exists := am.playerManagers[characterID]
	am.mutex.RUnlock()

	if exists {
		return playerMgr
	}

	// Create new player manager and load data
	am.mutex.Lock()
	defer am.mutex.Unlock()

	// Double-check after acquiring write lock
	if playerMgr, exists := am.playerManagers[characterID]; exists {
		return playerMgr
	}

	playerMgr = achievements.NewPlayerManager()
	am.playerManagers[characterID] = playerMgr

	// Load player achievement data from database
	go am.loadPlayerAchievements(characterID, playerMgr)

	return playerMgr
}

// loadPlayerAchievements loads achievement data for a specific player
func (am *AchievementManager) loadPlayerAchievements(characterID int32, playerMgr *achievements.PlayerManager) {
	// Load player achievements
	err := achievements.LoadPlayerAchievements(am.database, uint32(characterID), playerMgr.Achievements)
	if err != nil {
		fmt.Printf("Error loading achievements for character %d: %v\n", characterID, err)
	}

	// Load player progress
	err = achievements.LoadPlayerAchievementUpdates(am.database, uint32(characterID), playerMgr.Updates)
	if err != nil {
		fmt.Printf("Error loading achievement progress for character %d: %v\n", characterID, err)
	}
}

// UpdateProgress updates player progress for an achievement
func (am *AchievementManager) UpdateProgress(characterID int32, achievementID uint32, progress uint32) error {
	playerMgr := am.GetPlayerManager(characterID)
	if playerMgr == nil {
		return fmt.Errorf("failed to get player manager for character %d", characterID)
	}

	// Update progress
	playerMgr.Updates.UpdateProgress(achievementID, progress)

	// Check if achievement is completed
	achievement := am.masterList.GetAchievement(achievementID)
	if achievement != nil {
		completed, err := playerMgr.CheckRequirements(achievement)
		if err != nil {
			return fmt.Errorf("failed to check requirements: %w", err)
		}

		if completed && !playerMgr.Updates.IsCompleted(achievementID) {
			// Complete the achievement
			playerMgr.Updates.CompleteAchievement(achievementID)

			// Save progress to database
			go am.savePlayerProgress(characterID, achievementID, playerMgr)

			// Trigger achievement completion event
			go am.onAchievementCompleted(characterID, achievement)

			fmt.Printf("Character %d completed achievement: %s\n", characterID, achievement.Title)
		} else if progress > 0 {
			// Save progress update to database
			go am.savePlayerProgress(characterID, achievementID, playerMgr)
		}
	}

	return nil
}

// savePlayerProgress saves player achievement progress to database
func (am *AchievementManager) savePlayerProgress(characterID int32, achievementID uint32, playerMgr *achievements.PlayerManager) {
	update := playerMgr.Updates.GetUpdate(achievementID)
	if update == nil {
		return
	}

	err := achievements.SavePlayerAchievementUpdate(am.database, uint32(characterID), update)
	if err != nil {
		fmt.Printf("Error saving achievement progress for character %d, achievement %d: %v\n",
			characterID, achievementID, err)
	}
}

// onAchievementCompleted handles achievement completion events
func (am *AchievementManager) onAchievementCompleted(characterID int32, achievement *achievements.Achievement) {
	// Award points
	if achievement.PointValue > 0 {
		// Increment player's achievement points
		fmt.Printf("Character %d earned %d achievement points\n", characterID, achievement.PointValue)
	}

	// Process rewards
	for _, reward := range achievement.Rewards {
		am.processReward(characterID, reward)
	}

	// Notify other systems about achievement completion
	am.notifyAchievementCompleted(characterID, achievement.ID)
}

// notifyAchievementCompleted notifies other systems about achievement completion
func (am *AchievementManager) notifyAchievementCompleted(characterID int32, achievementID uint32) {
	// Notify title system if available
	if am.world != nil && am.world.titleMgr != nil {
		integrationMgr := am.world.titleMgr.GetIntegrationManager()
		if integrationMgr != nil {
			achievementIntegration := integrationMgr.GetAchievementIntegration()
			if achievementIntegration != nil {
				err := achievementIntegration.OnAchievementCompleted(characterID, achievementID)
				if err != nil {
					fmt.Printf("Error processing achievement completion for titles: %v\n", err)
				}
			}
		}
	}
}

// processReward processes an achievement reward
func (am *AchievementManager) processReward(characterID int32, reward achievements.Reward) {
	// Basic reward processing - extend based on reward types
	switch reward.Reward {
	case "title":
		// Award title
		fmt.Printf("Character %d earned a title reward\n", characterID)
	case "item":
		// Award item
		fmt.Printf("Character %d earned an item reward\n", characterID)
	case "experience":
		// Award experience
		fmt.Printf("Character %d earned experience reward\n", characterID)
	default:
		fmt.Printf("Character %d earned reward: %s\n", characterID, reward.Reward)
	}
}

// GetAchievement gets an achievement by ID from master list
func (am *AchievementManager) GetAchievement(achievementID uint32) *achievements.Achievement {
	return am.masterList.GetAchievement(achievementID)
}

// GetAchievementsByCategory gets achievements filtered by category
func (am *AchievementManager) GetAchievementsByCategory(category string) []*achievements.Achievement {
	return am.masterList.GetAchievementsByCategory(category)
}

// GetAchievementsByExpansion gets achievements filtered by expansion
func (am *AchievementManager) GetAchievementsByExpansion(expansion string) []*achievements.Achievement {
	return am.masterList.GetAchievementsByExpansion(expansion)
}

// GetPlayerProgress gets player's progress for an achievement
func (am *AchievementManager) GetPlayerProgress(characterID int32, achievementID uint32) uint32 {
	playerMgr := am.GetPlayerManager(characterID)
	if playerMgr == nil {
		return 0
	}

	return playerMgr.Updates.GetProgress(achievementID)
}

// IsPlayerCompleted checks if player has completed an achievement
func (am *AchievementManager) IsPlayerCompleted(characterID int32, achievementID uint32) bool {
	playerMgr := am.GetPlayerManager(characterID)
	if playerMgr == nil {
		return false
	}

	return playerMgr.Updates.IsCompleted(achievementID)
}

// GetPlayerCompletedAchievements gets all completed achievement IDs for a player
func (am *AchievementManager) GetPlayerCompletedAchievements(characterID int32) []uint32 {
	playerMgr := am.GetPlayerManager(characterID)
	if playerMgr == nil {
		return nil
	}

	return playerMgr.Updates.GetCompletedAchievements()
}

// GetPlayerInProgressAchievements gets all in-progress achievement IDs for a player
func (am *AchievementManager) GetPlayerInProgressAchievements(characterID int32) []uint32 {
	playerMgr := am.GetPlayerManager(characterID)
	if playerMgr == nil {
		return nil
	}

	return playerMgr.Updates.GetInProgressAchievements()
}

// GetCompletionPercentage gets completion percentage for player's achievement
func (am *AchievementManager) GetCompletionPercentage(characterID int32, achievementID uint32) float64 {
	playerMgr := am.GetPlayerManager(characterID)
	if playerMgr == nil {
		return 0.0
	}

	achievement := am.masterList.GetAchievement(achievementID)
	if achievement == nil {
		return 0.0
	}

	return playerMgr.GetCompletionStatus(achievement)
}

// RemovePlayerManager removes a player manager (called when player logs out)
func (am *AchievementManager) RemovePlayerManager(characterID int32) {
	am.mutex.Lock()
	defer am.mutex.Unlock()

	delete(am.playerManagers, characterID)
}

// GetStatistics returns achievement system statistics
func (am *AchievementManager) GetStatistics() map[string]any {
	am.mutex.RLock()
	defer am.mutex.RUnlock()

	stats := map[string]any{
		"total_achievements": am.masterList.Size(),
		"online_players":     len(am.playerManagers),
		"categories":         am.masterList.GetCategories(),
		"expansions":         am.masterList.GetExpansions(),
	}

	return stats
}

// Shutdown gracefully shuts down the achievement manager
func (am *AchievementManager) Shutdown() {
	fmt.Println("Shutting down achievement manager...")

	am.mutex.Lock()
	defer am.mutex.Unlock()

	// Save all player progress before shutdown
	for characterID, playerMgr := range am.playerManagers {
		for _, achievementID := range playerMgr.Updates.GetInProgressAchievements() {
			am.savePlayerProgress(characterID, achievementID, playerMgr)
		}
	}

	// Clear player managers
	am.playerManagers = make(map[int32]*achievements.PlayerManager)

	fmt.Println("Achievement manager shutdown complete")
}