/******************************************************************************
 * Spine Runtimes License Agreement
 * Last updated April 5, 2025. Replaces all prior versions.
 *
 * Copyright (c) 2013-2025, Esoteric Software LLC
 *
 * Integration of the Spine Runtimes into software or otherwise creating
 * derivative works of the Spine Runtimes is permitted under the terms and
 * conditions of Section 2 of the Spine Editor License Agreement:
 * http://esotericsoftware.com/spine-editor-license
 *
 * Otherwise, it is permitted to integrate the Spine Runtimes into software
 * or otherwise create derivative works of the Spine Runtimes (collectively,
 * "Products"), provided that each user of the Products must obtain their own
 * Spine Editor license and redistribution of the Products in any form must
 * include this license and copyright notice.
 *
 * THE SPINE RUNTIMES ARE PROVIDED BY ESOTERIC SOFTWARE LLC "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL ESOTERIC SOFTWARE LLC BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES,
 * BUSINESS INTERRUPTION, OR LOSS OF USE, DATA, OR PROFITS) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THE SPINE RUNTIMES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

import { MeshAttachment, RegionAttachment } from '@esotericsoftware/spine-core';
import {
	type BLEND_MODES,
	type Container, ExtensionType,
	extensions,
	type InstructionSet,
	type Renderer,
	type RenderPipe,
} from 'pixi.js';
import { BatchableSpineSlot } from './BatchableSpineSlot.js';
import type { Spine } from './Spine.js';

const spineBlendModeMap: Record<number, BLEND_MODES> = {
	0: 'normal',
	1: 'add',
	2: 'multiply',
	3: 'screen'
};

type GpuSpineDataElement = { slotBatches: Record<string, BatchableSpineSlot> };

// eslint-disable-next-line max-len
export class SpinePipe implements RenderPipe<Spine> {
	/** @ignore */
	static extension = {
		type: [
			ExtensionType.WebGLPipes,
			ExtensionType.WebGPUPipes,
			ExtensionType.CanvasPipes,
		],
		name: 'spine',
	} as const;

	renderer: Renderer;

	private gpuSpineData: Record<string, GpuSpineDataElement> = {};
	private readonly _destroyRenderableBound = this.destroyRenderable.bind(this) as (renderable: Container) => void;

	constructor (renderer: Renderer) {
		this.renderer = renderer;
	}

	validateRenderable (spine: Spine): boolean {
		spine._validateAndTransformAttachments();

		// if spine attachments have changed or destroyed, we need to rebuild the batch!
		if (spine.spineAttachmentsDirty) {
			return true;
		}

		// if the textures have changed, we need to rebuild the batch, but only if the texture is not already in the batch
		else if (spine.spineTexturesDirty) {
			// loop through and see if the textures have changed..
			const drawOrder = spine.skeleton.drawOrder;
			const gpuSpine = this.gpuSpineData[spine.uid];

			for (let i = 0, n = drawOrder.length; i < n; i++) {
				const slot = drawOrder[i];
				const attachment = slot.applied.attachment;

				if (attachment instanceof RegionAttachment || attachment instanceof MeshAttachment) {
					const cacheData = spine._getCachedData(slot, attachment);
					const batchableSpineSlot = gpuSpine.slotBatches[cacheData.id];

					const texture = cacheData.texture;

					if (texture !== batchableSpineSlot.texture) {
						if (!batchableSpineSlot._batcher.checkAndUpdateTexture(batchableSpineSlot, texture)) {
							return true;
						}
					}
				}
			}
		}

		return false;
	}

	addRenderable (spine: Spine, instructionSet: InstructionSet) {
		const gpuSpine = this._getSpineData(spine);

		const batcher = this.renderer.renderPipes.batch;

		const drawOrder = spine.skeleton.drawOrder;

		const roundPixels = (this.renderer._roundPixels | spine._roundPixels) as 0 | 1;

		spine._validateAndTransformAttachments();

		spine.spineAttachmentsDirty = false;
		spine.spineTexturesDirty = false;

		for (let i = 0, n = drawOrder.length; i < n; i++) {
			const slot = drawOrder[i];
			const attachment = slot.applied.attachment;
			const blendMode = spineBlendModeMap[slot.data.blendMode];
			let skipRender = false;

			if (attachment instanceof RegionAttachment || attachment instanceof MeshAttachment) {
				const cacheData = spine._getCachedData(slot, attachment);
				const batchableSpineSlot = gpuSpine.slotBatches[cacheData.id] ||= new BatchableSpineSlot();

				batchableSpineSlot.setData(
					spine,
					cacheData,
					blendMode,
					roundPixels
				);

				skipRender = cacheData.skipRender;
				if (!skipRender) {
					batcher.addToBatch(batchableSpineSlot, instructionSet);
				}
			}

			const containerAttachment = spine._slotsObject[slot.data.name];

			if (containerAttachment) {
				const container = containerAttachment.container;

				if (!skipRender) {
					container.includeInBuild = true;
					// See https://github.com/pixijs/pixijs/blob/b4c050a791fe65e979e467c9cba2bda0c01a1c35/src/scene/container/utils/collectAllRenderables.ts#L28
					container.collectRenderables(instructionSet, this.renderer, null!);
				}

				container.includeInBuild = false;
			}
		}
	}

	updateRenderable (spine: Spine) {
		const gpuSpine = this.gpuSpineData[spine.uid];

		spine._validateAndTransformAttachments();

		spine.spineAttachmentsDirty = false;
		spine.spineTexturesDirty = false;

		const drawOrder = spine.skeleton.drawOrder;

		for (let i = 0, n = drawOrder.length; i < n; i++) {
			const slot = drawOrder[i];
			const attachment = slot.applied.attachment;

			if (attachment instanceof RegionAttachment || attachment instanceof MeshAttachment) {
				const cacheData = spine._getCachedData(slot, attachment);

				if (!cacheData.skipRender) {
					const batchableSpineSlot = gpuSpine.slotBatches[spine._getCachedData(slot, attachment).id];

					batchableSpineSlot._batcher?.updateElement(batchableSpineSlot);
				}
			}
		}
	}

	destroyRenderable (spine: Spine) {
		this.gpuSpineData[spine.uid] = null as any;
		spine.off('destroyed', this._destroyRenderableBound);
	}

	destroy () {
		this.gpuSpineData = null as any;
		this.renderer = null as any;
	}

	private _getSpineData (spine: Spine): GpuSpineDataElement {
		return this.gpuSpineData[spine.uid] || this._initMeshData(spine);
	}

	private _initMeshData (spine: Spine): GpuSpineDataElement {
		this.gpuSpineData[spine.uid] = { slotBatches: {} };
		spine.on('destroyed', this._destroyRenderableBound);
		return this.gpuSpineData[spine.uid];
	}
}

extensions.add(SpinePipe);