extends RefCounted
class_name BotStrategicPlanner

# BotStrategicPlanner - Strategic decision-making for bot AI
# Evaluates tile needs, pathfinding targets, and sabotage opportunities

var actor: Node3D
var enhanced_gridmap: Node

# Tile type constants
const GOAL_TILES = [7, 8, 9, 10] # Heart, Diamond, Star, Coin
const HOLO_TILES = [11, 12, 13, 14] # Power-up holo tiles

func _init(p_actor: Node3D, p_gridmap: Node):
	actor = p_actor
	enhanced_gridmap = p_gridmap

# =============================================================================
# Goal Analysis
# =============================================================================

func calculate_goal_progress() -> float:
	"""Returns 0.0-1.0 representing how close bot is to completing their goal."""
	if not actor or actor.goals.size() == 0:
		return 0.0
	
	var matches = 0
	var total_required = 0
	
	# Check center 3x3 of playerboard against goals
	for i in range(3):
		for j in range(3):
			var goal_idx = i * 3 + j
			if goal_idx >= actor.goals.size():
				continue
			
			var goal_value = actor.goals[goal_idx]
			if goal_value == -1:
				continue # Empty goal slot
			
			total_required += 1
			var board_idx = (i + 1) * 5 + (j + 1) # Center 3x3 in 5x5 board
			if board_idx < actor.playerboard.size() and actor.playerboard[board_idx] == goal_value:
				matches += 1
	
	if total_required == 0:
		return 1.0 # All goals are -1 (empty)
	
	return float(matches) / float(total_required)

func get_tiles_needed() -> Array:
	"""Returns array of tile types still needed to complete goal."""
	var needed = []
	
	if not actor or actor.goals.size() == 0:
		return needed
	
	for i in range(3):
		for j in range(3):
			var goal_idx = i * 3 + j
			if goal_idx >= actor.goals.size():
				continue
			
			var goal_value = actor.goals[goal_idx]
			if goal_value == -1:
				continue
			
			var board_idx = (i + 1) * 5 + (j + 1)
			if board_idx >= actor.playerboard.size() or actor.playerboard[board_idx] != goal_value:
				if not goal_value in needed:
					needed.append(goal_value)
	
	return needed

func find_best_slot_for_tile(tile_type: int) -> int:
	"""Find the best playerboard slot for a given tile type."""
	# Check goals to find matching position
	for i in range(3):
		for j in range(3):
			var goal_idx = i * 3 + j
			if goal_idx < actor.goals.size() and actor.goals[goal_idx] == tile_type:
				var board_idx = (i + 1) * 5 + (j + 1)
				if board_idx < actor.playerboard.size() and actor.playerboard[board_idx] == -1:
					return board_idx
	
	# Fallback: any empty slot
	return actor.playerboard.find(-1)

# =============================================================================
# Tile Finding
# =============================================================================

func find_best_tile_to_grab() -> Dictionary:
	"""Find the best tile to grab, prioritizing goal tiles then holo tiles."""
	var needed_tiles = get_tiles_needed()
	var best_tile = {"position": null, "type": - 1, "priority": 0}
	
	if not enhanced_gridmap:
		return best_tile
	
	# Search nearby area for tiles
	var search_radius = 5
	var current_pos = actor.current_position
	
	for dx in range(-search_radius, search_radius + 1):
		for dz in range(-search_radius, search_radius + 1):
			var pos = Vector2i(current_pos.x + dx, current_pos.y + dz)
			if not enhanced_gridmap.is_position_valid(pos):
				continue
			
			var cell = Vector3i(pos.x, 1, pos.y)
			var item = enhanced_gridmap.get_cell_item(cell)
			
			if item == -1:
				continue
			
			var priority = 0
			
			# Priority 1: Tiles we need for goals
			if item in needed_tiles:
				priority = 10 - abs(dx) - abs(dz) # Closer = higher priority
			# Priority 2: Holo tiles for power-ups
			elif item in HOLO_TILES:
				priority = 5 - abs(dx) - abs(dz)
			elif item in GOAL_TILES:
				priority = 1 # Low priority - might be useful later
			
			if priority > best_tile.priority:
				best_tile = {"position": pos, "type": item, "priority": priority}
	
	return best_tile

func find_nearest_tile_of_type(tile_types: Array) -> Vector2i:
	"""Find nearest tile matching any type in array."""
	var current_pos = actor.current_position
	var nearest_pos = Vector2i(-1, -1)
	var nearest_dist = 999999
	
	if not enhanced_gridmap:
		return nearest_pos
	
	for x in range(enhanced_gridmap.columns):
		for z in range(enhanced_gridmap.rows):
			var pos = Vector2i(x, z)
			var cell = Vector3i(x, 1, z)
			var item = enhanced_gridmap.get_cell_item(cell)
			
			if item in tile_types:
				var dist = abs(pos.x - current_pos.x) + abs(pos.y - current_pos.y)
				if dist < nearest_dist:
					nearest_dist = dist
					nearest_pos = pos
	
	return nearest_pos

# =============================================================================
# Movement Strategy
# =============================================================================

func find_optimal_move_target() -> Vector2i:
	"""Calculate the best position to move towards."""
	var needed_tiles = get_tiles_needed()
	
	# First: move toward tiles we need
	if needed_tiles.size() > 0:
		var target = find_nearest_tile_of_type(needed_tiles)
		if target != Vector2i(-1, -1):
			return _get_adjacent_position(target)
	
	# Second: move toward holo tiles if we need power-ups
	var powerup_manager = actor.get_node_or_null("PowerUpManager")
	if powerup_manager and powerup_manager.current_points < powerup_manager.MAX_POINTS:
		var target = find_nearest_tile_of_type(HOLO_TILES)
		if target != Vector2i(-1, -1):
			return _get_adjacent_position(target)
	
	# Third: move toward any goal tile that might be useful
	var target = find_nearest_tile_of_type(GOAL_TILES)
	if target != Vector2i(-1, -1):
		return _get_adjacent_position(target)
	
	# Fallback: random valid position
	return _get_random_valid_position()

func _get_adjacent_position(target: Vector2i) -> Vector2i:
	"""Get a valid position adjacent to or at the target."""
	var current_pos = actor.current_position
	
	# If we can reach the target directly, return it
	if _is_within_movement_range(target):
		return target
	
	# Otherwise, move one step closer
	var dx = sign(target.x - current_pos.x)
	var dz = sign(target.y - current_pos.y)
	
	var positions_to_try = [
		Vector2i(current_pos.x + dx, current_pos.y + dz),
		Vector2i(current_pos.x + dx, current_pos.y),
		Vector2i(current_pos.x, current_pos.y + dz)
	]
	
	for pos in positions_to_try:
		if _is_valid_move_target(pos):
			return pos
	
	return Vector2i(-1, -1)

func _is_within_movement_range(pos: Vector2i) -> bool:
	var current_pos = actor.current_position
	var dist = max(abs(pos.x - current_pos.x), abs(pos.y - current_pos.y))
	return dist <= actor.movement_range

func _is_valid_move_target(pos: Vector2i) -> bool:
	if not enhanced_gridmap or not enhanced_gridmap.is_position_valid(pos):
		return false
	if actor.is_position_occupied(pos):
		return false
	return true

func _get_random_valid_position() -> Vector2i:
	var valid_positions = []
	var current_pos = actor.current_position
	var range_val = actor.movement_range
	
	for dx in range(-range_val, range_val + 1):
		for dz in range(-range_val, range_val + 1):
			if dx == 0 and dz == 0:
				continue
			var pos = Vector2i(current_pos.x + dx, current_pos.y + dz)
			if _is_valid_move_target(pos):
				valid_positions.append(pos)
	
	if valid_positions.size() > 0:
		return valid_positions[randi() % valid_positions.size()]
	return Vector2i(-1, -1)

# =============================================================================
# Sabotage Strategy
# =============================================================================

func evaluate_sabotage_opportunity() -> Dictionary:
	"""Evaluate whether to use power-up for sabotage."""
	var result = {"should_sabotage": false, "reason": "", "target": null}
	
	var powerup_manager = actor.get_node_or_null("PowerUpManager")
	if not powerup_manager or not powerup_manager.can_use_special():
		return result
	
	# Get opponents
	var opponents = _get_opponents()
	if opponents.size() == 0:
		return result
	
	# Check conditions for sabotage (balanced strategy)
	
	# Condition 1: Power-ups are maxed - use it or lose potential gains
	if powerup_manager.current_points >= powerup_manager.MAX_POINTS:
		result.should_sabotage = true
		result.reason = "max_powerup"
		result.target = opponents[randi() % opponents.size()]
		return result
	
	# Condition 2: Opponent is close to completing their goal
	for opponent in opponents:
		var opponent_progress = _estimate_opponent_progress(opponent)
		if opponent_progress >= 0.7: # 70% complete
			result.should_sabotage = true
			result.reason = "opponent_close_to_winning"
			result.target = opponent
			return result
	
	# Condition 3: Bot is behind in score - need to catch up
	var goals_cycle_manager = actor.get_tree().get_root().get_node_or_null("Main/GoalsCycleManager")
	if goals_cycle_manager:
		var leaderboard = goals_cycle_manager.get_leaderboard()
		var my_rank = _get_rank_in_leaderboard(leaderboard)
		if my_rank > 1 and powerup_manager.get_bars() >= 2:
			result.should_sabotage = true
			result.reason = "behind_in_score"
			result.target = opponents[0] if opponents.size() > 0 else null
			return result
	
	return result

func _get_opponents() -> Array:
	var all_players = actor.get_tree().get_nodes_in_group("Players")
	return all_players.filter(func(p): return p != actor)

func _estimate_opponent_progress(opponent: Node) -> float:
	"""Estimate opponent's goal progress based on their playerboard."""
	if not opponent or opponent.goals.size() == 0:
		return 0.0
	
	var matches = 0
	var total = 0
	
	for i in range(3):
		for j in range(3):
			var goal_idx = i * 3 + j
			if goal_idx >= opponent.goals.size():
				continue
			var goal_value = opponent.goals[goal_idx]
			if goal_value == -1:
				continue
			total += 1
			var board_idx = (i + 1) * 5 + (j + 1)
			if board_idx < opponent.playerboard.size() and opponent.playerboard[board_idx] == goal_value:
				matches += 1
	
	return float(matches) / float(max(total, 1))

func _get_rank_in_leaderboard(leaderboard: Array) -> int:
	var my_id = actor.get_multiplayer_authority()
	for i in range(leaderboard.size()):
		if leaderboard[i].get("peer_id", -1) == my_id:
			return i + 1
	return leaderboard.size() + 1