// Enhanced Occlusion Layer Module for Foundry VTT

export function registerOcclusionLayerConfig2ForUpload() {
	// Global Hook Registration
	function registerGlobalHooks() {
		// Update triggers for occlusion layer
		const updateTriggers = [
			'canvasReady', 
			'canvasPan',
			'canvasTokensRefresh', 
			'updateToken', 
			'controlToken', 
			'refreshToken',
			'preUpdateScene',  // Added to ensure update on scene modifications
			'updateScene'      // Added to ensure update on scene modifications
		];

		updateTriggers.forEach(hookName => {
			Hooks.on(hookName, () => {
				updateOcclusionLayer();
			});
		});
	}

	// Initial layer setup
	Hooks.once('ready', () => {
		if (canvas.ready)
			initializeOcclusionLayer();
	});

	// Initialize on canvas setup
	Hooks.on('canvasInit', () => {
		initializeOcclusionLayer();
	});

	// Reset on scene change
	Hooks.on('changeScene', () => {
		if (occlusionConfig.container) {
			canvas.stage.removeChild(occlusionConfig.container);
			occlusionConfig.container.destroy({ children: true });
			occlusionConfig.container = null;
			occlusionConfig.tokensLayer = null;
			occlusionConfig.initialized = false;
		}
	});

	// Start the module
	registerGlobalHooks();
}











// Persistent occlusion layer configuration
const occlusionConfig = {
	container: null,
	tokensLayer: null,
	initialized: false
};

// Initialize or reset the occlusion layer
function initializeOcclusionLayer() {
	// Remove existing container if it exists
	if (occlusionConfig.container) {
		canvas.stage.removeChild(occlusionConfig.container);
		occlusionConfig.container.destroy({ children: true });
	}

	// Create the main occlusion container
	occlusionConfig.container = new PIXI.Container();
	occlusionConfig.container.name = "OcclusionContainer";
	occlusionConfig.container.eventMode = 'passive';

	// Create a layer for occlusion tokens
	occlusionConfig.tokensLayer = new PIXI.Container();
	occlusionConfig.tokensLayer.name = "OcclusionTokens";
	occlusionConfig.tokensLayer.sortableChildren = true;

	// Add the layer to the container
	occlusionConfig.container.addChild(occlusionConfig.tokensLayer);

	// Add to canvas stage
	canvas.stage.addChild(occlusionConfig.container);
	canvas.stage.sortChildren();

	occlusionConfig.initialized = true;
}


// Comprehensive update mechanism for occlusion layer
function updateOcclusionLayer() {
	// Ensure canvas is ready and layer is initialized
	if (!canvas.ready) return;

	// Reinitialize if not yet set up
	if (!occlusionConfig.initialized) {
		initializeOcclusionLayer();
	}

	// Clear existing occlusion tokens
	occlusionConfig.tokensLayer.removeChildren();

	// Get all tokens and tiles
	const tokens = canvas.tokens.placeables;
	const tiles = canvas.tiles.placeables;

	tokens.forEach(token => {
		// Find tiles that intersect with this token
		const intersectingTiles = tiles.filter(tile => 
			checkTokenTileIntersection(token, tile)
		);

		// If there are intersecting tiles, create an occlusion sprite
		if (intersectingTiles.length > 0) {
			const occlusionSprite = createOcclusionSprite(token, intersectingTiles);
			if (occlusionSprite) {
				occlusionConfig.tokensLayer.addChild(occlusionSprite);
			}
		}
	});
}

// Token-Tile Intersection Check
function checkTokenTileIntersection(token, tile) {
	// Basic intersection check using bounding boxes
	const tokenBounds = token.mesh.getBounds();
	const tileBounds = tile.mesh.getBounds();

	return (
		tokenBounds.x < tileBounds.x + tileBounds.width &&
		tokenBounds.x + tokenBounds.width > tileBounds.x &&
		tokenBounds.y < tileBounds.y + tileBounds.height &&
		tokenBounds.y + tokenBounds.height > tileBounds.y
	);
}

// Create Occlusion Sprite with Advanced Masking
function createOcclusionSprite(token, intersectingTiles) {
	if (!token.mesh || !token.mesh.texture) return null;

	// Create a sprite from the token's texture
	const sprite = new PIXI.Sprite(token.mesh.texture);
	sprite.position.set(token.mesh.position.x, token.mesh.position.y);
	sprite.anchor.set(token.mesh.anchor.x, token.mesh.anchor.y);
	sprite.angle = token.mesh.angle;
	sprite.scale.set(token.mesh.scale.x, token.mesh.scale.y);

	// Create a mask for the occlusion
	const mask = createOcclusionMask(token, intersectingTiles);
	if (mask) {
		sprite.mask = mask;
	}

	// Create new outline filter
	const outlineFilter = new PIXI.filters.isoOutlineFilter();
	outlineFilter.thickness = 0.005;
	outlineFilter.color = 0x00ff59;
		
	// Create a greyscale/dimming filter
	const colorMatrix = new PIXI.ColorMatrixFilter();
	colorMatrix.alpha = 1;
	colorMatrix.matrix = [
		0.3,  0.0,  0.0,  0.0,  0.0,
		0.0,  0.3,  0.0,  0.0,  0.0,
		0.0,  0.0,  0.3,  0.0,  0.0,
		0.0,  0.0,  0.0,  1.0,  0.0
	];

	// Create new alpha filter
	//const alphaFilter = new PIXI.AlphaFilter();
	//alphaFilter.alpha = 0.5;


	sprite.filters = [colorMatrix, outlineFilter];

	//sprite.alpha = 0.75;
	sprite.eventMode = 'passive';

	return sprite;
}














// Advanced Occlusion Mask Creation
// Advanced Occlusion Mask Creation
function createOcclusionMask(token, intersectingTiles) {
	const maskGraphics = new PIXI.Graphics();
	maskGraphics.beginFill(0xffffff);

	intersectingTiles.forEach(tile => {
			const tokenBounds = token.mesh.getBounds();
			const tileBounds = tile.mesh.getBounds();
					
			// Calculate intersection area
			const intersectionX = Math.max(tokenBounds.x, tileBounds.x);
			const intersectionY = Math.max(tokenBounds.y, tileBounds.y);
			const intersectionWidth = Math.min(tokenBounds.x + tokenBounds.width, tileBounds.x + tileBounds.width) - intersectionX;
			const intersectionHeight = Math.min(tokenBounds.y + tokenBounds.height, tileBounds.y + tileBounds.height) - intersectionY;

			// Validate intersection
			if (intersectionWidth > 0 && intersectionHeight > 0) {
					// Access tile texture
					const tileTexture = tile.texture?.baseTexture?.resource?.source;
					if (!tileTexture) {
							console.warn("Invalid tile texture", tile);
							return;
					}

					// Validate texture dimensions
					if (tileTexture.width <= 0 || tileTexture.height <= 0) {
							console.warn("Invalid tile texture dimensions", {
									width: tileTexture.width, 
									height: tileTexture.height
							});
							return;
					}

					const canvas = document.createElement("canvas");
					const ctx = canvas.getContext("2d");
							
					// Set canvas dimensions to match tile texture
					canvas.width = tileTexture.width;
					canvas.height = tileTexture.height;
							
					// Draw the tile texture
					ctx.drawImage(tileTexture, 0, 0);

					// Calculate relative position within the tile
					const tileScale = {
							x: tileBounds.width / tileTexture.width,
							y: tileBounds.height / tileTexture.height
					};

					// Convert intersection coordinates to tile texture space
					const textureX = (intersectionX - tileBounds.x) / tileScale.x;
					const textureY = (intersectionY - tileBounds.y) / tileScale.y;
					const textureWidth = intersectionWidth / tileScale.x;
					const textureHeight = intersectionHeight / tileScale.y;

					// Sample image data from the correct region of the tile texture
					const imageData = ctx.getImageData(
							Math.floor(textureX),
							Math.floor(textureY),
							Math.ceil(textureWidth),
							Math.ceil(textureHeight)
					);
					const data = imageData.data;

					// Create a path for non-transparent pixels
					maskGraphics.beginFill(0xffffff);
					
					const pixelSize = {
							x: intersectionWidth / imageData.width,
							y: intersectionHeight / imageData.height
					};

					for (let y = 0; y < imageData.height; y++) {
							for (let x = 0; x < imageData.width; x++) {
									const i = (y * imageData.width + x) * 4;
									const alpha = data[i + 3];

									if (alpha > 0) {  // Only draw for non-transparent pixels
											maskGraphics.drawRect(
													intersectionX + (x * pixelSize.x),
													intersectionY + (y * pixelSize.y),
													pixelSize.x,
													pixelSize.y
											);
									}
							}
					}
					maskGraphics.endFill();

					// Clean up
					canvas.remove();
			}
	});

	return maskGraphics;
}























// Definição do isoOutlineFilter
if (typeof PIXI !== 'undefined' && PIXI.filters) {
	const vertexShader =`
		attribute vec2 aVertexPosition;
		attribute vec2 aTextureCoord;

		uniform mat3 projectionMatrix;
		varying vec2 vTextureCoord;

		void main(void) {
			gl_Position = vec4((projectionMatrix * vec3(aVertexPosition, 1.0)).xy, 0.0, 1.0);
			vTextureCoord = aTextureCoord;
		}
	`;

	const fragmentShader = `
		varying vec2 vTextureCoord;

		uniform sampler2D uSampler;
		uniform float alpha;
		uniform vec2 outlineThickness;
		uniform vec4 outlineColor;
		uniform vec4 filterArea;
		uniform vec4 filterClamp;

		void main(void) {
			vec4 ownColor = texture2D(uSampler, vTextureCoord);
			vec4 curColor;
			float maxAlpha = 0.0;
			vec2 displaced;

			for (float angle = 0.0; angle < 6.28318530718; angle += 0.78539816339) {
				displaced.x = vTextureCoord.x + outlineThickness.x * cos(angle);
				displaced.y = vTextureCoord.y + outlineThickness.y * sin(angle);
				curColor = texture2D(uSampler, displaced);
				maxAlpha = max(maxAlpha, curColor.a);
			}
			float resultAlpha = max(maxAlpha, ownColor.a);
			gl_FragColor = vec4((ownColor.rgb * ownColor.a + outlineColor.rgb * (1.0 - ownColor.a)) * resultAlpha, resultAlpha);
		 }
	`;

	// Defina a classe isoOutlineFilter
	class IsoOutlineFilter extends PIXI.Filter {
		constructor(thickness = 1, color = 0x000000, alpha = 1) {
			super(vertexShader, fragmentShader);

			// Inicialize os uniforms
			this.uniforms.outlineColor = new Float32Array(4); // Para armazenar RGBA
			this.uniforms.outlineThickness = new Float32Array(2); // Para armazenar X e Y
			this.uniforms.filterArea = new Float32Array(2); // Para área de filtro
			this.uniforms.alpha = alpha;

			// Configure as propriedades iniciais
			this.color = color;
			this.thickness = thickness;
		}

		get alpha() {
			return this.uniforms.alpha;
		}
		set alpha(value) {
			this.uniforms.alpha = value;
		}

		get color() {
			return PIXI.utils.rgb2hex(this.uniforms.outlineColor);
		}
		set color(value) {
			PIXI.utils.hex2rgb(value, this.uniforms.outlineColor);
		}

		get thickness() {
			return this.uniforms.outlineThickness[0];
		}
		set thickness(value) {
			// Certifique-se de que filterArea tenha valores válidos
			const filterAreaX = this.uniforms.filterArea[0] || 1; // Evite divisão por 0
			const filterAreaY = this.uniforms.filterArea[1] || 1; // Evite divisão por 0
			
			this.uniforms.outlineThickness[0] = value / filterAreaX;
			this.uniforms.outlineThickness[1] = value / filterAreaY;
		}
	}

	// Adicione o isoOutlineFilter ao namespace PIXI.filters
	PIXI.filters.isoOutlineFilter = IsoOutlineFilter;
} else {
	console.error('PIXI ou PIXI.filters não estão disponíveis.');
}