package combat

import (
	"math"
	"sync"
	"time"
)

// HateManager manages hate/threat for all entities in combat
type HateManager struct {
	hateLists   map[int32]*HateList
	hatesMutex  sync.RWMutex
	config      *CombatConfig
}

// NewHateManager creates a new hate manager
func NewHateManager(config *CombatConfig) *HateManager {
	return &HateManager{
		hateLists:  make(map[int32]*HateList),
		config:     config,
	}
}

// AddHate adds hate/threat to an entity's hate list
func (hm *HateManager) AddHate(ownerID int32, targetID int32, hateAmount int32, lockHate bool) {
	hm.hatesMutex.Lock()
	defer hm.hatesMutex.Unlock()

	// Get or create hate list
	hateList, exists := hm.hateLists[ownerID]
	if !exists {
		hateList = NewHateList(ownerID)
		hm.hateLists[ownerID] = hateList
	}

	hateList.mutex.Lock()
	defer hateList.mutex.Unlock()

	// Get or create hate entry
	hateEntry, exists := hateList.HateEntries[targetID]
	if !exists {
		hateEntry = NewHateEntry(targetID, 0)
		hateList.HateEntries[targetID] = hateEntry
	}

	// Add hate
	hateEntry.HateAmount += hateAmount
	hateEntry.LastHit = time.Now()
	if lockHate {
		hateEntry.IsLocked = true
	}

	// Update most hated
	hm.updateMostHated(hateList)
	hateList.LastUpdate = time.Now()
}

// RemoveHate removes hate from a target
func (hm *HateManager) RemoveHate(ownerID int32, targetID int32, hateAmount int32) {
	hm.hatesMutex.Lock()
	defer hm.hatesMutex.Unlock()

	hateList, exists := hm.hateLists[ownerID]
	if !exists {
		return
	}

	hateList.mutex.Lock()
	defer hateList.mutex.Unlock()

	hateEntry, exists := hateList.HateEntries[targetID]
	if !exists {
		return
	}

	// Remove hate
	hateEntry.HateAmount -= hateAmount
	if hateEntry.HateAmount <= 0 && !hateEntry.IsLocked {
		delete(hateList.HateEntries, targetID)
	}

	// Update most hated
	hm.updateMostHated(hateList)
	hateList.LastUpdate = time.Now()
}

// SetHate sets the exact hate amount for a target
func (hm *HateManager) SetHate(ownerID int32, targetID int32, hateAmount int32) {
	hm.hatesMutex.Lock()
	defer hm.hatesMutex.Unlock()

	hateList, exists := hm.hateLists[ownerID]
	if !exists {
		hateList = NewHateList(ownerID)
		hm.hateLists[ownerID] = hateList
	}

	hateList.mutex.Lock()
	defer hateList.mutex.Unlock()

	hateEntry, exists := hateList.HateEntries[targetID]
	if !exists {
		hateEntry = NewHateEntry(targetID, hateAmount)
		hateList.HateEntries[targetID] = hateEntry
	} else {
		hateEntry.HateAmount = hateAmount
	}

	hateEntry.LastHit = time.Now()
	
	// Update most hated
	hm.updateMostHated(hateList)
	hateList.LastUpdate = time.Now()
}

// ClearHate clears all hate for a specific owner
func (hm *HateManager) ClearHate(ownerID int32) {
	hm.hatesMutex.Lock()
	defer hm.hatesMutex.Unlock()

	delete(hm.hateLists, ownerID)
}

// ClearHateTarget removes a target from all hate lists
func (hm *HateManager) ClearHateTarget(targetID int32) {
	hm.hatesMutex.Lock()
	defer hm.hatesMutex.Unlock()

	for _, hateList := range hm.hateLists {
		hateList.mutex.Lock()
		delete(hateList.HateEntries, targetID)
		hm.updateMostHated(hateList)
		hateList.mutex.Unlock()
	}
}

// GetHateList returns a copy of the hate list for an entity
func (hm *HateManager) GetHateList(ownerID int32) *HateList {
	hm.hatesMutex.RLock()
	defer hm.hatesMutex.RUnlock()

	originalList, exists := hm.hateLists[ownerID]
	if !exists {
		return nil
	}

	// Create a copy to prevent external modification
	copyList := &HateList{
		OwnerID:     originalList.OwnerID,
		HateEntries: make(map[int32]*HateEntry),
		MostHated:   originalList.MostHated,
		LastUpdate:  originalList.LastUpdate,
	}

	originalList.mutex.RLock()
	defer originalList.mutex.RUnlock()

	for id, entry := range originalList.HateEntries {
		copyList.HateEntries[id] = &HateEntry{
			TargetID:     entry.TargetID,
			HateAmount:   entry.HateAmount,
			DamageAmount: entry.DamageAmount,
			LastHit:      entry.LastHit,
			IsLocked:     entry.IsLocked,
		}
	}

	return copyList
}

// GetMostHated returns the most hated target for an entity
func (hm *HateManager) GetMostHated(ownerID int32) int32 {
	hm.hatesMutex.RLock()
	defer hm.hatesMutex.RUnlock()

	if hateList, exists := hm.hateLists[ownerID]; exists {
		return hateList.MostHated
	}
	return 0
}

// GetHateAmount returns the hate amount for a specific target
func (hm *HateManager) GetHateAmount(ownerID int32, targetID int32) int32 {
	hm.hatesMutex.RLock()
	defer hm.hatesMutex.RUnlock()

	hateList, exists := hm.hateLists[ownerID]
	if !exists {
		return 0
	}

	hateList.mutex.RLock()
	defer hateList.mutex.RUnlock()

	if hateEntry, exists := hateList.HateEntries[targetID]; exists {
		return hateEntry.HateAmount
	}
	return 0
}

// HasHateTarget checks if an owner has hate toward a specific target
func (hm *HateManager) HasHateTarget(ownerID int32, targetID int32) bool {
	return hm.GetHateAmount(ownerID, targetID) > 0
}

// GetTopHateTargets returns the top N hate targets for an entity
func (hm *HateManager) GetTopHateTargets(ownerID int32, count int) []int32 {
	hateList := hm.GetHateList(ownerID)
	if hateList == nil || len(hateList.HateEntries) == 0 {
		return nil
	}

	// Create slice of entries for sorting
	type hateTarget struct {
		targetID int32
		hate     int32
	}

	targets := make([]hateTarget, 0, len(hateList.HateEntries))
	for targetID, entry := range hateList.HateEntries {
		targets = append(targets, hateTarget{
			targetID: targetID,
			hate:     entry.HateAmount,
		})
	}

	// Simple bubble sort for top N (sufficient for small hate lists)
	for i := 0; i < len(targets)-1; i++ {
		for j := 0; j < len(targets)-i-1; j++ {
			if targets[j].hate < targets[j+1].hate {
				targets[j], targets[j+1] = targets[j+1], targets[j]
			}
		}
	}

	// Return top N target IDs
	result := make([]int32, 0, count)
	for i := 0; i < count && i < len(targets); i++ {
		result = append(result, targets[i].targetID)
	}

	return result
}

// ProcessHateDecay applies hate decay over time
func (hm *HateManager) ProcessHateDecay(currentTime time.Time) {
	hm.hatesMutex.Lock()
	defer hm.hatesMutex.Unlock()

	for ownerID, hateList := range hm.hateLists {
		hateList.mutex.Lock()
		
		timeDiff := float32(currentTime.Sub(hateList.LastUpdate).Seconds())
		decayAmount := int32(timeDiff * hm.config.HateDecayRate)
		
		if decayAmount > 0 {
			hasHate := false
			for targetID, entry := range hateList.HateEntries {
				if !entry.IsLocked {
					entry.HateAmount -= decayAmount
					if entry.HateAmount <= 0 {
						delete(hateList.HateEntries, targetID)
					} else {
						hasHate = true
					}
				} else {
					hasHate = true
				}
			}
			
			hateList.LastUpdate = currentTime
			
			// Remove empty hate lists
			if !hasHate {
				hateList.mutex.Unlock()
				delete(hm.hateLists, ownerID)
				continue
			}
			
			// Update most hated
			hm.updateMostHated(hateList)
		}
		
		hateList.mutex.Unlock()
	}
}

// LockHate locks hate for a target (prevents decay)
func (hm *HateManager) LockHate(ownerID int32, targetID int32, lock bool) {
	hm.hatesMutex.Lock()
	defer hm.hatesMutex.Unlock()

	hateList, exists := hm.hateLists[ownerID]
	if !exists {
		return
	}

	hateList.mutex.Lock()
	defer hateList.mutex.Unlock()

	if hateEntry, exists := hateList.HateEntries[targetID]; exists {
		hateEntry.IsLocked = lock
	}
}

// CalculateHateModifier calculates hate modifier based on various factors
func (hm *HateManager) CalculateHateModifier(attacker Entity, victim Entity, damageAmount int32, isHealing bool) float32 {
	modifier := float32(1.0)

	// Level difference affects hate generation
	levelDiff := float32(attacker.GetLevel() - victim.GetLevel())
	if levelDiff > 0 {
		// Higher level attacker generates more hate
		modifier += levelDiff * 0.02
	} else if levelDiff < 0 {
		// Lower level attacker generates less hate
		modifier += levelDiff * 0.01
	}

	// Distance affects hate (closer = more threatening)
	distance := hm.calculateDistance(attacker, victim)
	if distance > 100.0 {
		modifier *= 0.8 // Reduced hate for distant attackers
	}

	// Healing generates less hate than damage
	if isHealing {
		modifier *= 0.5
	}

	// Critical hits generate more hate
	if damageAmount > 0 {
		// Check if this was a particularly high damage hit
		avgLevel := float32(attacker.GetLevel() + victim.GetLevel()) / 2.0
		expectedDamage := avgLevel * 10.0 // Rough estimate
		if float32(damageAmount) > expectedDamage*1.5 {
			modifier *= 1.25 // Bonus hate for high damage
		}
	}

	// Cap modifier
	if modifier > 2.0 {
		modifier = 2.0
	} else if modifier < 0.1 {
		modifier = 0.1
	}

	return modifier
}

// GetHateListCount returns the number of active hate lists
func (hm *HateManager) GetHateListCount() int {
	hm.hatesMutex.RLock()
	defer hm.hatesMutex.RUnlock()
	return len(hm.hateLists)
}

// GetTotalHateEntries returns the total number of hate entries across all lists
func (hm *HateManager) GetTotalHateEntries() int {
	hm.hatesMutex.RLock()
	defer hm.hatesMutex.RUnlock()

	total := 0
	for _, hateList := range hm.hateLists {
		hateList.mutex.RLock()
		total += len(hateList.HateEntries)
		hateList.mutex.RUnlock()
	}
	return total
}

// updateMostHated updates the most hated target in a hate list (internal method)
func (hm *HateManager) updateMostHated(hateList *HateList) {
	var maxHate int32
	var mostHated int32

	for targetID, entry := range hateList.HateEntries {
		if entry.HateAmount > maxHate {
			maxHate = entry.HateAmount
			mostHated = targetID
		}
	}

	hateList.MostHated = mostHated
}

// calculateDistance calculates distance between two entities
func (hm *HateManager) calculateDistance(entity1 Entity, entity2 Entity) float32 {
	dx := entity1.GetX() - entity2.GetX()
	dy := entity1.GetY() - entity2.GetY()
	dz := entity1.GetZ() - entity2.GetZ()
	
	return float32(math.Sqrt(float64(dx*dx + dy*dy + dz*dz)))
}

// Shutdown cleans up the hate manager
func (hm *HateManager) Shutdown() {
	hm.hatesMutex.Lock()
	defer hm.hatesMutex.Unlock()
	hm.hateLists = make(map[int32]*HateList)
}