import 'element-behaviors'
import {stringAttribute} from '@lume/element'
import {onCleanup, createEffect} from 'solid-js'
import {signal} from 'classy-solid'
import {ProjectedMaterial} from '@lume/three-projected-material/dist/ProjectedMaterial.js'
import {OrthographicCamera} from 'three/src/cameras/OrthographicCamera.js'
import {Texture} from 'three/src/textures/Texture.js'
import {behavior} from '../../Behavior.js'
import {receiver} from '../../PropReceiver.js'
import {PhysicalMaterialBehavior, type PhysicalMaterialBehaviorAttributes} from './PhysicalMaterialBehavior.js'
import {TextureProjector} from '../../../textures/TextureProjector.js'
import type {Element3D} from '../../../core/Element3D.js'
import {upwardRoots} from '../../../utils/upwardRoots.js'
import {querySelectorUpward} from '../../../utils/querySelectorUpward.js'

export type ProjectedMaterialBehaviorAttributes =
	| PhysicalMaterialBehaviorAttributes
	| 'textureProjectors'
	| 'projectedTextures' // deprecated

/**
 * @class ProjectedMaterialBehavior
 *
 * Behavior: `projected-material`
 *
 * A physical material with the added ability to have additional textures
 * projected onto it with
 * [`<lume-texture-projector>`](../../../textures/TextureProjector) elements.
 *
 * Project a texture onto a mesh using a `<lume-texture-projector>` and
 * associating it with the `texture-projectors` attribute:
 *
 * ```html
 * <!-- Define a texture projector somewhere. -->
 * <lume-texture-projector src="path/to/image.jpg" class="some-projector"></lume-texture-projector>
 *
 * <!-- Use the projected-material on the mesh, and associate it with the projector: -->
 * <lume-box
 *   has="projected-material"
 *   size="100 100 100"
 *   texture-projectors=".some-projector"
 * ></lume-box>
 * ```
 *
 * <live-code id="example"></live-code>
 * <script>
 *   example.content = projectedTextureExample
 * </script>
 *
 * @extends PhysicalMaterialBehavior
 */
export
@behavior
class ProjectedMaterialBehavior extends PhysicalMaterialBehavior {
	/** The computed value after the user sets this.textureProjectors. F.e. any strings are queried from DOM, and this array contains only DOM element references. */
	@signal accessor #associatedProjectors: Array<TextureProjector> = []

	/**
	 * @property {Array<TextureProjector>} associatedProjectors
	 *
	 * `readonly` `signal`
	 *
	 * The list of `TextureProjector` elements that are projecting onto the
	 * current owner element, normalized from
	 * [`.textureProjectors`](#textureprojectors) with selectors queried and
	 * null values ignored.
	 *
	 * This returns the currently associated array of `<lume-texture-projector>`
	 * instances, not the original string or array of values passed to
	 * [`.textureProjectors`](#textureprojectors).
	 */
	get associatedProjectors() {
		return this.#associatedProjectors
	}

	/** The raw value the user set on this.textureProjectors */
	#textureProjectorsRaw: string | Array<TextureProjector | string> = []

	/**
	 * @property {string | Array<TextureProjector | string | null>} textureProjectors
	 *
	 * `string attribute`
	 *
	 * Default: `[]`
	 *
	 * The `texture-projectors` attribute accepts one or more selectors, comma
	 * separated, that define which
	 * [`<lume-texture-projector>`](../../core/TextureProjector) elements are to
	 * project an image onto the owner element. If a selector matches an element
	 * that is not a `<lume-texture-projector>`, it is ignored (note that
	 * non-upgraded elements will not be detected, make sure to load element
	 * definitions up front which is the default if you're simply importing
	 * `lume`).
	 * If a selector matches
	 * more than one element, only the first `<lume-texture-projector>` will be used
	 * (in the near future we will allow multiple projectors to project).
	 *
	 * ```html
	 * <lume-box has="projected-material" texture-projectors=".foo, .bar, #baz"></lume-box>
	 * ```
	 *
	 * The `textureProjectors` JS property can be set with a string of comma
	 * separated selectors, or a mixed array of strings (selectors) or
	 * `<lume-texture-projector>` element instances, making the JS property more
	 * flexible for scenarios where selectors are not enough (f.e. maybe you
	 * need to get a reference to an element from some other part of the DOM,
	 * perhaps from a tree inside a ShadowRoot, or you are programmatically
	 * creating elements, etc).
	 *
	 * ```js
	 * el.textureProjectors = ".some-texture-projector"
	 * // or
	 * const projector = document.querySelector('.some-texture-projector')
	 * el.textureProjectors = [projector, "#someOtherTextureProjector"]
	 * ```
	 *
	 * Texture projectors that are not in the composed tree (i.e. not
	 * participating in rendering) will be ignored.  The texture projectors that
	 * will be associated are those that are connected into the document, and
	 * that participate in rendering (i.e.  composed, either in the top level
	 * document, in a ShadowRoot, or distributed to a slot in a ShadowRoot).
	 * This is the same as with the browser's built-in elements: a `<div>`
	 * element that is connected into the DOM but not slotted to its parent's
	 * `.shadowRoot` will not participate in the visual output.
	 */
	@stringAttribute @receiver get textureProjectors(): string | Array<TextureProjector | string> {
		return this.#textureProjectorsRaw
	}
	@stringAttribute set textureProjectors(value: string | Array<TextureProjector | string>) {
		this.#textureProjectorsRaw = value
	}

	/**
	 * @deprecated
	 * @property {string | Array<TextureProjector | string | null>} projectedTextures
	 *
	 * `string attribute`
	 *
	 * *deprecated*: renamed to [`.textureProjectors`](#textureprojectors).
	 */
	@stringAttribute @receiver get projectedTextures() {
		return this.textureProjectors
	}
	@stringAttribute set projectedTextures(value) {
		this.textureProjectors = value
	}

	override _createComponent() {
		// TODO multiple projected textures.
		// Only one projected texture for now. Handling a material array is
		// needed for multiple projections, unless we update ProjectedMaterial
		// to supported multiple textures/cameras so that we can have a single
		// material. Probably the mat.project and mat.updateFromCamera methods
		// should accept a camera from the outside rather than using one that is
		// contained in the material.
		return new ProjectedMaterial()
	}

	#observer: MutationObserver | null = null

	override connectedCallback() {
		super.connectedCallback()

		let queuedRequery = false

		this.#observer = new MutationObserver(() => {
			if (queuedRequery) return

			queuedRequery = true

			// Use a timeout for batching so this doesn't run a ton of times during DOM parsing.
			setTimeout(() => {
				queuedRequery = false

				// TODO this could be more efficient if we check the added nodes directly, but for now we re-run the query logic.
				// This triggers the setter logic.
				this.textureProjectors = this.#textureProjectorsRaw
			}, 0)
		})

		for (const root of upwardRoots(this.element)) this.#observer.observe(root, {childList: true, subtree: true})

		this.createEffect(() => {
			const mat = this.meshComponent
			if (!mat) return

			const three = this.element.three
			if (three.material !== mat) return

			createEffect(() => {
				this.textureProjectors

				let array: Array<TextureProjector | string> = []

				if (typeof this.#textureProjectorsRaw === 'string') {
					array = [this.#textureProjectorsRaw.trim()]
				} else if (Array.isArray(this.#textureProjectorsRaw)) {
					array = this.#textureProjectorsRaw
				} else {
					throw new TypeError('Invalid value for textureProjectors')
				}

				const projectors = []

				for (const value of array) {
					if (typeof value !== 'string') {
						// Consider only elements that participate in rendering (i.e. that are in the composed tree)
						if (value.scene && value instanceof TextureProjector) projectors.push(value)
						continue
					} else if (!value) {
						// skip empty strings, they cause an error with querySelectorAll
						continue
					}

					// TODO Should we not search up the composed tree, and stay only
					// in the current ShadowRoot?

					for (const el of querySelectorUpward(this.element, value)) {
						if (!el) continue

						// Consider only elements that participate in rendering (i.e. that are in the composed tree)
						if ((el as Element3D).scene && el instanceof TextureProjector) projectors.push(el)

						// TODO If an element was not yet upgraded, it will not
						// be found here. We could wait for upgrade.
					}
				}

				this.#associatedProjectors = projectors // trigger
			})

			this._handleTexture(
				() => this.#associatedProjectors[0]?.src ?? '',
				(mat, tex) => (mat.texture = tex || new Texture()),
				mat => !!mat.texture,
				() => {},
				true,
			)

			createEffect(() => {
				const tex = this.#associatedProjectors[0]
				if (!tex) return

				createEffect(() => {
					mat.fitment = tex.fitment
					mat.frontFacesOnly = tex.frontFacesOnly
					this.element.needsUpdate()
				})
			})

			createEffect(() => {
				const tex = this.#associatedProjectors[0]
				if (!tex) return

				// if the camera changes
				const cam = tex.threeCamera
				if (!cam) return

				if (three.material !== mat) return

				mat.camera = cam
				mat.updateFromCamera()
				mat.project(three as any, false)

				this.element.needsUpdate()

				// Do we need this?
				onCleanup(() => {
					const mat = this.meshComponent

					// If the whole behavior was cleaned up, mat will be undefined
					// here due to #disposeMeshComponent in the base class onCleanup
					if (!mat) return

					if (three.material !== mat) return

					mat.camera = new OrthographicCamera(0.00000001, 0.00000001, 0.00000001, 0.00000001)
					mat.updateFromCamera()
					mat.project(three as any, false)

					this.element.needsUpdate()
				})
			})

			createEffect(() => {
				const tex = this.#associatedProjectors[0]
				if (!tex) return

				createEffect(() => {
					tex.calculatedSize // dependency

					mat.updateFromCamera() // needed because the size of the texture projector affects the camera projection
					this.element.needsUpdate()
				})
			})

			createEffect(() => {
				if (three.material !== mat) return

				// triggered when this.element has its world matrix updated.
				this.element.version
				mat.project(three as any, false)
			})

			createEffect(() => {
				const tex = this.#associatedProjectors[0]
				if (!tex) return

				createEffect(() => {
					if (three.material !== mat) return

					// triggered when tex has its world matrix updated, which
					// transforms the camera we use for texture projection.
					tex.version
					mat.project(three as any, false)
					this.element.needsUpdate() // The texture element updated, so make sure this.element does too.
				})
			})
		})
	}

	override disconnectedCallback(): void {
		super.disconnectedCallback()

		this.#observer?.disconnect()
		this.#observer = null
	}
}

if (globalThis.window?.document && !elementBehaviors.has('projected-material'))
	elementBehaviors.define('projected-material', ProjectedMaterialBehavior)