import BlueprintTemplate from "./template/BlueprintTemplate"
import Configuration from "./Configuration"
import Copy from "./input/common/Copy"
import IElement from "./element/IElement"
import KeyboardCanc from "./input/keybaord/KeyboardCanc"
import KeyboardSelectAll from "./input/keybaord/KeyboardSelectAll"
import LinkElement from "./element/LinkElement"
import MouseScrollGraph from "./input/mouse/MouseScrollGraph"
import MouseTracking from "./input/mouse/MouseTracking"
import NodeElement from "./element/NodeElement"
import Paste from "./input/common/Paste"
import Select from "./input/mouse/Select"
import SelectorElement from "./element/SelectorElement"
import Unfocus from "./input/mouse/Unfocus"
import Utility from "./Utility"
import Zoom from "./input/mouse/Zoom"

export default class Blueprint extends IElement {

    static tagName = "ueb-blueprint"
    /** @type {number} */
    gridSize = Configuration.gridSize
    /** @type {NodeElement[]}" */
    nodes = []
    /** @type {LinkElement[]}" */
    links = []
    expandGridSize = Configuration.expandGridSize
    /** @type {number[]} */
    additional = /*[2 * this.expandGridSize, 2 * this.expandGridSize]*/[0, 0]
    /** @type {number[]} */
    translateValue = /*[this.expandGridSize, this.expandGridSize]*/[0, 0]
    /** @type {number[]} */
    mousePosition = [0, 0]
    /** @type {HTMLElement} */
    gridElement = null
    /** @type {HTMLElement} */
    viewportElement = null
    /** @type {HTMLElement} */
    overlayElement = null
    /** @type {SelectorElement} */
    selectorElement = null
    /** @type {HTMLElement} */
    nodesContainerElement = null
    /** @type {number} */
    zoom = 0
    /** @type {HTMLElement} */
    headerElement = null
    focused = false
    /** @type {(node: NodeElement) => BoundariesInfo} */
    nodeBoundariesSupplier = node => {
        let rect = node.getBoundingClientRect()
        let gridRect = this.nodesContainerElement.getBoundingClientRect()
        const scaleCorrection = 1 / this.getScale()
        return {
            primaryInf: (rect.left - gridRect.left) * scaleCorrection,
            primarySup: (rect.right - gridRect.right) * scaleCorrection,
            // Counter intuitive here: the y (secondary axis is positive towards the bottom, therefore upper bound "sup" is bottom)
            secondaryInf: (rect.top - gridRect.top) * scaleCorrection,
            secondarySup: (rect.bottom - gridRect.bottom) * scaleCorrection
        }
    }
    /** @type {(node: NodeElement, selected: bool) => void}} */
    nodeSelectToggleFunction = (node, selected) => {
        node.setSelected(selected)
    }

    constructor() {
        super({}, new BlueprintTemplate())
        /** @type {BlueprintTemplate} */
        this.template
    }

    /**
     * Expand the grid, considers the absolute value of params
     * @param {number} x - Horizontal expansion value
     * @param {number} y - Vertical expansion value
     */
    #expand(x, y) {
        x = Math.round(Math.abs(x))
        y = Math.round(Math.abs(y))
        this.additional = [this.additional[0] + x, this.additional[1] + y]
        this.template.applyExpand(this)
    }

    /**
     * Moves the content of the grid according to the coordinates
     * @param {number} x - Horizontal translation value
     * @param {number} y - Vertical translation value
     */
    #translate(x, y) {
        x = Math.round(x)
        y = Math.round(y)
        this.translateValue = [this.translateValue[0] + x, this.translateValue[1] + y]
        this.template.applyTranlate(this)
    }

    createInputObjects() {
        return [
            new Copy(this.getGridDOMElement(), this),
            new Paste(this.getGridDOMElement(), this),
            new KeyboardCanc(this.getGridDOMElement(), this),
            new KeyboardSelectAll(this.getGridDOMElement, this),
            new Zoom(this.getGridDOMElement(), this, {
                looseTarget: true,
            }),
            new Select(this.getGridDOMElement(), this, {
                clickButton: 0,
                exitAnyButton: true,
                looseTarget: true,
                moveEverywhere: true,
            }),
            new MouseScrollGraph(this.getGridDOMElement(), this, {
                clickButton: 2,
                exitAnyButton: false,
                looseTarget: true,
                moveEverywhere: true,
            }),
            new Unfocus(this.getGridDOMElement(), this),
            new MouseTracking(this.getGridDOMElement(), this)
        ]
    }

    getGridDOMElement() {
        return this.gridElement
    }

    disconnectedCallback() {
        super.disconnectedCallback()
        setSelected(false)
    }

    getScroll() {
        return [this.viewportElement.scrollLeft, this.viewportElement.scrollTop]
    }

    setScroll(value, smooth = false) {
        this.scroll = value
        if (!smooth) {
            this.viewportElement.scroll(value[0], value[1])
        } else {
            this.viewportElement.scroll({
                left: value[0],
                top: value[1],
                behavior: "smooth"
            })
        }
    }

    scrollDelta(delta, smooth = false) {
        const scrollMax = this.getScrollMax()
        let currentScroll = this.getScroll()
        let finalScroll = [
            currentScroll[0] + delta[0],
            currentScroll[1] + delta[1]
        ]
        let expand = [0, 0]
        for (let i = 0; i < 2; ++i) {
            if (delta[i] < 0 && finalScroll[i] < 0.25 * this.expandGridSize) {
                // Expand if scrolling is diminishing and the remainig space is less that a quarter of an expansion step
                expand[i] = finalScroll[i]
                if (expand[i] > 0) {
                    // Final scroll is still in rage (more than zero) but we want to expand to negative (left or top)
                    expand[i] = -this.expandGridSize
                }
            } else if (delta[i] > 0 && finalScroll[i] > scrollMax[i] - 0.25 * this.expandGridSize) {
                // Expand if scrolling is increasing and the remainig space is less that a quarter of an expansion step
                expand[i] = finalScroll[i] - scrollMax[i]
                if (expand[i] < 0) {
                    // Final scroll is still in rage (less than the maximum scroll) but we want to expand to positive (right or bottom)
                    expand[i] = this.expandGridSize
                }
            }
        }
        if (expand[0] != 0 || expand[1] != 0) {
            this.seamlessExpand(this.progressiveSnapToGrid(expand[0]), this.progressiveSnapToGrid(expand[1]))
            currentScroll = this.getScroll()
            finalScroll = [
                currentScroll[0] + delta[0],
                currentScroll[1] + delta[1]
            ]
        }
        this.setScroll(finalScroll, smooth)
    }

    scrollCenter() {
        const scroll = this.getScroll()
        const offset = [
            this.translateValue[0] - scroll[0],
            this.translateValue[1] - scroll[1]
        ]
        const targetOffset = this.getViewportSize().map(size => size / 2)
        const deltaOffset = [
            offset[0] - targetOffset[0],
            offset[1] - targetOffset[1]
        ]
        this.scrollDelta(deltaOffset, true)
    }

    getExpandGridSize() {
        return this.expandGridSize
    }

    getViewportSize() {
        return [
            this.viewportElement.clientWidth,
            this.viewportElement.clientHeight
        ]
    }

    /**
     * Get the scroll limits
     * @return {array} The horizonal and vertical maximum scroll limits
     */
    getScrollMax() {
        return [
            this.viewportElement.scrollWidth - this.viewportElement.clientWidth,
            this.viewportElement.scrollHeight - this.viewportElement.clientHeight
        ]
    }

    snapToGrid(location) {
        return Utility.snapToGrid(location, this.gridSize)
    }

    /**
     * Expand the grind indefinitely, the content will remain into position
     * @param {number} x - Horizontal expand value (negative means left, positive means right)
     * @param {number} y - Vertical expand value (negative means top, positive means bottom)
     */
    seamlessExpand(x, y) {
        let scale = this.getScale()
        let scaledX = x / scale
        let scaledY = y / scale
        // First expand the grid to contain the additional space
        this.#expand(scaledX, scaledY)
        // If the expansion is towards the left or top, then scroll back to give the illusion that the content is in the same position and translate it accordingly
        this.#translate(scaledX < 0 ? -scaledX : 0, scaledY < 0 ? -scaledY : 0)
        if (x < 0) {
            this.viewportElement.scrollLeft -= x
        }
        if (y < 0) {
            this.viewportElement.scrollTop -= y
        }
    }

    progressiveSnapToGrid(x) {
        return this.expandGridSize * Math.round(x / this.expandGridSize + 0.5 * Math.sign(x))
    }

    getZoom() {
        return this.zoom
    }

    setZoom(zoom, center) {
        zoom = Utility.clamp(zoom, -12, 0)
        if (zoom == this.zoom) {
            return
        }
        let initialScale = this.getScale()
        this.template.applyZoom(this, zoom)
        this.zoom = zoom

        if (center) {
            center[0] += this.translateValue[0]
            center[1] += this.translateValue[1]
            let relativeScale = this.getScale() / initialScale
            let newCenter = [
                relativeScale * center[0],
                relativeScale * center[1]
            ]
            this.scrollDelta([
                (newCenter[0] - center[0]) * initialScale,
                (newCenter[1] - center[1]) * initialScale
            ])
        }
    }

    getScale() {
        return parseFloat(getComputedStyle(this.gridElement).getPropertyValue("--ueb-scale"))
    }

    compensateTranslation(position) {
        position[0] -= this.translateValue[0]
        position[1] -= this.translateValue[1]
        return position
    }

    /**
     * Returns the list of nodes in this blueprint. It can filter the list providing just the selected ones.
     * @returns {NodeElement[]} Nodes
     */
    getNodes(selected = false) {
        if (selected) {
            return this.nodes.filter(
                node => node.selected
            )
        } else {
            return this.nodes
        }
    }

    /**
     * Returns the list of links in this blueprint.
     * @returns {LinkElement[]} Nodes
     */
    getLinks([a, b] = []) {
        if (a == null != b == null) {
            const pin = a ?? b
            return this.links.filter(link => link.getSourcePin() == pin || link.getDestinationPin() == pin)
        }
        if (a != null && b != null) {
            return this.links.filter(link =>
                link.getSourcePin() == a && link.getDestinationPin() == b
                || link.getSourcePin() == b && link.getDestinationPin() == a)
        }
        return this.links
    }

    /**
     * Select all nodes
     */
    selectAll() {
        this.getNodes().forEach(node => this.nodeSelectToggleFunction(node, true))
    }

    /**
     * Unselect all nodes
     */
    unselectAll() {
        this.getNodes().forEach(node => this.nodeSelectToggleFunction(node, false))
    }

    /**
     * @param  {...IElement} graphElements
     */
    addGraphElement(...graphElements) {
        if (this.nodesContainerElement) {
            graphElements.forEach(element => {
                if (element.closest(Blueprint.tagName) != this) {
                    this.nodesContainerElement.appendChild(element)
                }
                this.nodes = [...this.querySelectorAll(NodeElement.tagName)]
                this.links = [...this.querySelectorAll(LinkElement.tagName)]
            })
        } else {
            graphElements.forEach(element => {
                if (element instanceof NodeElement) {
                    this.nodes.push(element)
                } else if (element instanceof LinkElement) {
                    this.links.push(element)
                }
            })
        }
    }

    /**
     * @param  {...IElement} graphElements
     */
    removeGraphElement(...graphElements) {
        let removed = false
        graphElements.forEach(element => {
            if (element.closest(Blueprint.tagName) == this) {
                element.remove()
                removed = false
            }
        })
        if (removed) {
            this.nodes = [...this.querySelectorAll(NodeElement.tagName)]
            this.links = [...this.querySelectorAll(LinkElement.tagName)]
        }
    }

    setFocused(value = true) {
        if (this.focused == value) {
            return
        }
        let event = new CustomEvent(value ? "blueprint-focus" : "blueprint-unfocus")
        this.focused = value
        this.dataset.focused = this.focused
        if (!this.focused) {
            this.unselectAll()
        }
        this.dispatchEvent(event)
    }
}

customElements.define(Blueprint.tagName, Blueprint)