package titles

import (
	"fmt"
	"sync"
)

// MasterTitlesList manages all available titles in the game
type MasterTitlesList struct {
	titles        map[int32]*Title    // All titles indexed by ID
	categorized   map[string][]*Title // Titles grouped by category
	bySource      map[int32][]*Title  // Titles grouped by source
	byRarity      map[int32][]*Title  // Titles grouped by rarity
	byAchievement map[uint32]*Title   // Titles indexed by achievement ID
	nextID        int32               // Next available title ID
	mutex         sync.RWMutex        // Thread safety
}

// NewMasterTitlesList creates a new master titles list
func NewMasterTitlesList() *MasterTitlesList {
	mtl := &MasterTitlesList{
		titles:        make(map[int32]*Title),
		categorized:   make(map[string][]*Title),
		bySource:      make(map[int32][]*Title),
		byRarity:      make(map[int32][]*Title),
		byAchievement: make(map[uint32]*Title),
		nextID:        1,
	}

	// Initialize default titles
	mtl.initializeDefaultTitles()

	return mtl
}

// initializeDefaultTitles creates the basic system titles
func (mtl *MasterTitlesList) initializeDefaultTitles() {
	// System titles with negative IDs
	citizen := NewTitle(TitleIDCitizen, "Citizen")
	citizen.SetDescription("Default citizen title")
	citizen.SetFlag(FlagStarter)
	citizen.Position = TitlePositionSuffix
	mtl.addTitleInternal(citizen)

	visitor := NewTitle(TitleIDVisitor, "Visitor")
	visitor.SetDescription("Temporary visitor status")
	visitor.SetFlag(FlagTemporary)
	visitor.Position = TitlePositionSuffix
	mtl.addTitleInternal(visitor)

	newcomer := NewTitle(TitleIDNewcomer, "Newcomer")
	newcomer.SetDescription("New player welcome title")
	newcomer.SetFlag(FlagStarter)
	newcomer.ExpirationHours = 168 // 1 week
	newcomer.Position = TitlePositionPrefix
	mtl.addTitleInternal(newcomer)

	returning := NewTitle(TitleIDReturning, "Returning")
	returning.SetDescription("Welcome back title for returning players")
	returning.SetFlag(FlagTemporary)
	returning.ExpirationHours = 72 // 3 days
	returning.Position = TitlePositionPrefix
	mtl.addTitleInternal(returning)
}

// AddTitle adds a new title to the master list
func (mtl *MasterTitlesList) AddTitle(title *Title) error {
	mtl.mutex.Lock()
	defer mtl.mutex.Unlock()

	if title == nil {
		return fmt.Errorf("cannot add nil title")
	}

	// Assign ID if not set
	if title.ID == 0 {
		title.ID = mtl.nextID
		mtl.nextID++
	}

	// Check for duplicate ID
	if _, exists := mtl.titles[title.ID]; exists {
		return fmt.Errorf("title with ID %d already exists", title.ID)
	}

	// Validate title name length
	if len(title.Name) > MaxTitleNameLength {
		return fmt.Errorf("title name exceeds maximum length of %d characters", MaxTitleNameLength)
	}

	// Validate description length
	if len(title.Description) > MaxTitleDescriptionLength {
		return fmt.Errorf("title description exceeds maximum length of %d characters", MaxTitleDescriptionLength)
	}

	// Check for unique titles
	if title.IsUnique() {
		// TODO: Check if any player already has this unique title
	}

	return mtl.addTitleInternal(title)
}

// addTitleInternal adds a title without validation (used internally)
func (mtl *MasterTitlesList) addTitleInternal(title *Title) error {
	// Add to main map
	mtl.titles[title.ID] = title

	// Add to category index
	if mtl.categorized[title.Category] == nil {
		mtl.categorized[title.Category] = make([]*Title, 0)
	}
	mtl.categorized[title.Category] = append(mtl.categorized[title.Category], title)

	// Add to source index
	if mtl.bySource[title.Source] == nil {
		mtl.bySource[title.Source] = make([]*Title, 0)
	}
	mtl.bySource[title.Source] = append(mtl.bySource[title.Source], title)

	// Add to rarity index
	if mtl.byRarity[title.Rarity] == nil {
		mtl.byRarity[title.Rarity] = make([]*Title, 0)
	}
	mtl.byRarity[title.Rarity] = append(mtl.byRarity[title.Rarity], title)

	// Add to achievement index if applicable
	if title.AchievementID > 0 {
		mtl.byAchievement[title.AchievementID] = title
	}

	// Update next ID if necessary
	if title.ID >= mtl.nextID {
		mtl.nextID = title.ID + 1
	}

	return nil
}

// GetTitle retrieves a title by ID
func (mtl *MasterTitlesList) GetTitle(id int32) (*Title, bool) {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	title, exists := mtl.titles[id]
	if !exists {
		return nil, false
	}

	return title.Clone(), true
}

// GetTitleByName retrieves a title by name (case-sensitive)
func (mtl *MasterTitlesList) GetTitleByName(name string) (*Title, bool) {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	for _, title := range mtl.titles {
		if title.Name == name {
			return title.Clone(), true
		}
	}

	return nil, false
}

// GetTitleByAchievement retrieves a title associated with an achievement
func (mtl *MasterTitlesList) GetTitleByAchievement(achievementID uint32) (*Title, bool) {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	title, exists := mtl.byAchievement[achievementID]
	if !exists {
		return nil, false
	}

	return title.Clone(), true
}

// GetTitlesByCategory retrieves all titles in a specific category
func (mtl *MasterTitlesList) GetTitlesByCategory(category string) []*Title {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	titles := mtl.categorized[category]
	if titles == nil {
		return make([]*Title, 0)
	}

	// Return clones to prevent external modification
	result := make([]*Title, len(titles))
	for i, title := range titles {
		result[i] = title.Clone()
	}

	return result
}

// GetTitlesBySource retrieves all titles from a specific source
func (mtl *MasterTitlesList) GetTitlesBySource(source int32) []*Title {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	titles := mtl.bySource[source]
	if titles == nil {
		return make([]*Title, 0)
	}

	// Return clones to prevent external modification
	result := make([]*Title, len(titles))
	for i, title := range titles {
		result[i] = title.Clone()
	}

	return result
}

// GetTitlesByRarity retrieves all titles of a specific rarity
func (mtl *MasterTitlesList) GetTitlesByRarity(rarity int32) []*Title {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	titles := mtl.byRarity[rarity]
	if titles == nil {
		return make([]*Title, 0)
	}

	// Return clones to prevent external modification
	result := make([]*Title, len(titles))
	for i, title := range titles {
		result[i] = title.Clone()
	}

	return result
}

// GetAllTitles retrieves all titles (excluding hidden ones by default)
func (mtl *MasterTitlesList) GetAllTitles(includeHidden bool) []*Title {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	result := make([]*Title, 0, len(mtl.titles))

	for _, title := range mtl.titles {
		if !includeHidden && title.IsHidden() {
			continue
		}
		result = append(result, title.Clone())
	}

	return result
}

// GetAvailableCategories returns all categories that have titles
func (mtl *MasterTitlesList) GetAvailableCategories() []string {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	categories := make([]string, 0, len(mtl.categorized))
	for category := range mtl.categorized {
		categories = append(categories, category)
	}

	return categories
}

// RemoveTitle removes a title from the master list
func (mtl *MasterTitlesList) RemoveTitle(id int32) error {
	mtl.mutex.Lock()
	defer mtl.mutex.Unlock()

	title, exists := mtl.titles[id]
	if !exists {
		return fmt.Errorf("title with ID %d does not exist", id)
	}

	// Remove from main map
	delete(mtl.titles, id)

	// Remove from category index
	mtl.removeFromSlice(&mtl.categorized[title.Category], title)
	if len(mtl.categorized[title.Category]) == 0 {
		delete(mtl.categorized, title.Category)
	}

	// Remove from source index
	mtl.removeFromSlice(&mtl.bySource[title.Source], title)
	if len(mtl.bySource[title.Source]) == 0 {
		delete(mtl.bySource, title.Source)
	}

	// Remove from rarity index
	mtl.removeFromSlice(&mtl.byRarity[title.Rarity], title)
	if len(mtl.byRarity[title.Rarity]) == 0 {
		delete(mtl.byRarity, title.Rarity)
	}

	// Remove from achievement index if applicable
	if title.AchievementID > 0 {
		delete(mtl.byAchievement, title.AchievementID)
	}

	return nil
}

// removeFromSlice removes a title from a slice
func (mtl *MasterTitlesList) removeFromSlice(slice *[]*Title, title *Title) {
	for i, t := range *slice {
		if t.ID == title.ID {
			*slice = append((*slice)[:i], (*slice)[i+1:]...)
			break
		}
	}
}

// UpdateTitle updates an existing title
func (mtl *MasterTitlesList) UpdateTitle(title *Title) error {
	mtl.mutex.Lock()
	defer mtl.mutex.Unlock()

	if title == nil {
		return fmt.Errorf("cannot update with nil title")
	}

	existing, exists := mtl.titles[title.ID]
	if !exists {
		return fmt.Errorf("title with ID %d does not exist", title.ID)
	}

	// Remove old title from indices
	mtl.removeFromSlice(&mtl.categorized[existing.Category], existing)
	mtl.removeFromSlice(&mtl.bySource[existing.Source], existing)
	mtl.removeFromSlice(&mtl.byRarity[existing.Rarity], existing)

	if existing.AchievementID > 0 {
		delete(mtl.byAchievement, existing.AchievementID)
	}

	// Update the title
	mtl.titles[title.ID] = title

	// Re-add to indices with new values
	if mtl.categorized[title.Category] == nil {
		mtl.categorized[title.Category] = make([]*Title, 0)
	}
	mtl.categorized[title.Category] = append(mtl.categorized[title.Category], title)

	if mtl.bySource[title.Source] == nil {
		mtl.bySource[title.Source] = make([]*Title, 0)
	}
	mtl.bySource[title.Source] = append(mtl.bySource[title.Source], title)

	if mtl.byRarity[title.Rarity] == nil {
		mtl.byRarity[title.Rarity] = make([]*Title, 0)
	}
	mtl.byRarity[title.Rarity] = append(mtl.byRarity[title.Rarity], title)

	if title.AchievementID > 0 {
		mtl.byAchievement[title.AchievementID] = title
	}

	return nil
}

// GetTitleCount returns the total number of titles
func (mtl *MasterTitlesList) GetTitleCount() int {
	mtl.mutex.RLock()
	defer mtl.mutex.RUnlock()

	return len(mtl.titles)
}

// ValidateTitle checks if a title meets all requirements
func (mtl *MasterTitlesList) ValidateTitle(title *Title) error {
	if title == nil {
		return fmt.Errorf("title cannot be nil")
	}

	if len(title.Name) == 0 {
		return fmt.Errorf("title name cannot be empty")
	}

	if len(title.Name) > MaxTitleNameLength {
		return fmt.Errorf("title name exceeds maximum length of %d characters", MaxTitleNameLength)
	}

	if len(title.Description) > MaxTitleDescriptionLength {
		return fmt.Errorf("title description exceeds maximum length of %d characters", MaxTitleDescriptionLength)
	}

	if len(title.Requirements) > MaxTitleRequirements {
		return fmt.Errorf("title has too many requirements (max %d)", MaxTitleRequirements)
	}

	// Validate position
	if title.Position != TitlePositionPrefix && title.Position != TitlePositionSuffix {
		return fmt.Errorf("invalid title position: %d", title.Position)
	}

	// Validate rarity
	if title.Rarity < TitleRarityCommon || title.Rarity > TitleRarityUnique {
		return fmt.Errorf("invalid title rarity: %d", title.Rarity)
	}

	return nil
}

// LoadFromDatabase would load titles from the database
// TODO: Implement database integration with zone/database package
func (mtl *MasterTitlesList) LoadFromDatabase() error {
	// TODO: Implement database loading
	return fmt.Errorf("LoadFromDatabase not yet implemented - requires database integration")
}

// SaveToDatabase would save titles to the database
// TODO: Implement database integration with zone/database package
func (mtl *MasterTitlesList) SaveToDatabase() error {
	// TODO: Implement database saving
	return fmt.Errorf("SaveToDatabase not yet implemented - requires database integration")
}