import { CellSaveState } from '../engine'
import { hexToRgb, IColor } from '../models/colors'
import { GameData } from '../models/game'
import { A11Y_MESSAGE, A11Y_MESSAGE_TYPE } from '../models/rule'
import { GameSprite } from '../models/tile'
import { Soundish } from '../parser/astTypes'
// import { playSound } from '../sound/sfxr'
import {
    _flatten,
    Cellish,
    EmptyGameEngineHandler,
    GameEngineHandler,
    GameEngineHandlerOptional,
    INPUT_BUTTON,
    Optional,
    RULE_DIRECTION,
    setIntersection,
    spritesThatInteractWithPlayer
} from '../util'
import BaseUI from './base'

interface ITableCell {
    td: HTMLTableCellElement,
    label: HTMLSpanElement,
    pixels: HTMLSpanElement[][]
}

function mapIncrement<T>(map: Map<T, number>, item: T) {
    const num = map.get(item)
    map.set(item, num ? num + 1 : 1)
}

class TableUI extends BaseUI implements GameEngineHandler {
    private readonly table: HTMLElement
    private readonly liveLog: Element
    private inputsProcessed: number
    private tableCells: ITableCell[][]
    private handler: EmptyGameEngineHandler
    private interactsWithPlayer: Set<GameSprite>
    private usedInMessages: Set<GameSprite>
    private didPressCauseTick: boolean
    private silencedOutput: boolean
    private messagesSincePress: number
    private isCollecting: boolean
    private collectedSprites: Map<GameSprite, number>
    private collectingTickCount: number

    constructor(table: HTMLElement, handler?: GameEngineHandlerOptional) {
        super()
        this.table = table
        this.tableCells = []
        this.inputsProcessed = 0
        this.interactsWithPlayer = new Set()
        this.usedInMessages = new Set()
        table.classList.add('ps-table')
        this.markAcceptingInput(false)

        // To use this as a handler, the functions need to be bound to `this`
        this.onPress = this.onPress.bind(this)
        this.onLevelChange = this.onLevelChange.bind(this)

        this.handler = new EmptyGameEngineHandler(handler ? [handler] : [])

        const liveLog = table.querySelector('[aria-live]') || document.querySelector('[aria-live]')
        if (!liveLog) {
            throw new Error(`Error: For screenreaders to work, an element inside the table (for now) with an aria-live attribute needs to exist in the initial page. See https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/ARIA_Live_Regions`) // tslint:disable-line:max-line-length
        }
        this.liveLog = liveLog

        this.didPressCauseTick = false
        this.silencedOutput = false
        this.messagesSincePress = 0
        this.isCollecting = false
        this.collectedSprites = new Map()
        this.collectingTickCount = 0
    }

    public onPause() {
        this.table.setAttribute('data-ps-state', 'paused')
        this.handler.onPause()
    }
    public onResume() {
        this.table.setAttribute('data-ps-state', 'running')
        this.handler.onResume()
    }
    public onGameChange(gameData: GameData) {
        super.onGameChange(gameData)
        this.silencedOutput = false
        this.didPressCauseTick = false
        this.interactsWithPlayer = spritesThatInteractWithPlayer(this.getGameData())
        this.usedInMessages = new Set(this.interactsWithPlayer)
        this.collectedSprites.clear()
        this.handler.onGameChange(gameData)
    }

    public onPress(dir: INPUT_BUTTON) {
        this.didPressCauseTick = true
        this.liveLog.innerHTML = '' // clear out the log
        this.markAcceptingInput(false)
        switch (dir) {
            case INPUT_BUTTON.UNDO:
            case INPUT_BUTTON.RESTART:
                this.renderScreen(false)
        }
        this.handler.onPress(dir)
    }

    public onLevelLoad(level: number, newLevelSize: Optional<{rows: number, cols: number}>) {
        this.handler.onLevelLoad(level, newLevelSize)
    }
    public onLevelChange(levelNum: number, cells: Optional<Cellish[][]>, message: Optional<string>) {
        this.clearScreen()
        this.table.setAttribute('data-ps-current-level', `${levelNum}`)

        if (cells) {
            super.onLevelChange(levelNum, cells, message)
            // Draw the level
            // Draw the empty table
            this.tableCells = []
            const gameData = this.getGameData()
            const { width, height } = gameData.metadata.flickscreen || gameData.metadata.zoomscreen || { width: cells[0].length, height: cells.length }

            this.table.setAttribute('tabindex', '0')
            const tbody = document.createElement('tbody')
            for (let currentY = 0; currentY < height; currentY++) {
                const tr = document.createElement('tr')
                const tableRow = []

                // Add the row header with a summary of which sprites are in the row
                // const th = document.createElement('th')
                // th.classList.add('ps-row-summary')
                // th.textContent = 'Sprites in Row:'
                // tr.appendChild(th)

                for (let currentX = 0; currentX < width; currentX++) {
                    const td = document.createElement('td')
                    const tableCellPixels = []
                    td.classList.add('ps-cell')

                    const cellLabel = document.createElement('span')
                    cellLabel.classList.add('ps-cell-label')
                    td.appendChild(cellLabel)

                    const sprite = document.createElement('div')
                    sprite.classList.add('ps-sprite-whole')
                    sprite.setAttribute('aria-hidden', 'true')

                    for (let row = 0; row < this.SPRITE_HEIGHT; row++) {
                        const spriteRow = document.createElement('div')
                        spriteRow.classList.add('ps-sprite-row')
                        const pixelRow = []

                        for (let col = 0; col < this.SPRITE_WIDTH; col++) {
                            const spritePixel = document.createElement('span')
                            spritePixel.classList.add('ps-sprite-pixel')
                            spriteRow.appendChild(spritePixel)
                            pixelRow.push(spritePixel)
                        }
                        sprite.appendChild(spriteRow)
                        tableCellPixels.push(pixelRow)
                    }
                    td.appendChild(sprite)
                    tr.appendChild(td)
                    tableRow.push({ td, label: cellLabel, pixels: tableCellPixels })
                }
                tbody.appendChild(tr)
                this.tableCells.push(tableRow)
            }
            this.table.prepend(tbody)

            for (const row of cells) {
                this.drawCells(row, false)
            }
        }
        this.markAcceptingInput(true)
        this.handler.onLevelChange(levelNum, cells, message)
    }

    public async onMessage(msg: string) {
        await this.handler.onMessage(msg)
    }
    public onWin() {
        this.handler.onWin()
    }
    public async onSound(sound: Soundish) {
        // playSound(sound.soundCode) // tslint:disable-line:no-floating-promises
        await this.handler.onSound(sound)
    }
    public onTick(changedCells: Set<Cellish>, checkpoint: Optional<CellSaveState>, hasAgain: boolean, a11yMessages: Array<A11Y_MESSAGE<Cellish, GameSprite>>) {
        this.collectingTickCount++
        this.printMessageLog(a11yMessages, hasAgain)
        this.drawCells(changedCells, false)
        this.markAcceptingInput(!hasAgain)
        this.didPressCauseTick = false
        this.handler.onTick(changedCells, checkpoint, hasAgain, a11yMessages)
    }

    public willAllLevelsFitOnScreen(gameData: GameData) {
        return true
    }

    public _drawPixel(x: number, y: number, fgHex: string, bgHex: Optional<string>, chars: string) {
        const rowIndex = Math.floor(y / this.SPRITE_HEIGHT)
        const colIndex = Math.floor(x / this.SPRITE_WIDTH)
        const pixelY = y % this.SPRITE_HEIGHT
        const pixelX = x % this.SPRITE_WIDTH

        const pixel = this.tableCells[rowIndex][colIndex].pixels[pixelY][pixelX]
        if (!pixel) {
            throw new Error(`BUG: Could not set pixel because table is too small`)
        }
        let style = `color: ${fgHex};`
        if (bgHex) {
            style += ` background-color: ${bgHex};`
        }
        pixel.setAttribute('style', style)
        // pixel.textContent = chars
    }

    public clearScreen() {
        super.clearScreen()
        // clear all the rows
        const tbody = this.table.querySelector('tbody')
        tbody && tbody.remove()
        this.liveLog.innerHTML = ''
        this.tableCells = []
    }

    protected renderLevelScreen(levelRows: Cellish[][], renderScreenDepth: number) {
        this.drawCells(_flatten(levelRows), false, renderScreenDepth)
    }

    protected setPixel(x: number, y: number, hex: string, fgHex: Optional<string>, chars: string) {
        const rowIndex = Math.floor(y / this.SPRITE_HEIGHT)
        const colIndex = Math.floor(x / this.SPRITE_WIDTH)
        const pixelY = y % this.SPRITE_HEIGHT
        const pixelX = x % this.SPRITE_WIDTH

        const pixel = this.tableCells[rowIndex][colIndex].pixels[pixelY][pixelX]
        if (!pixel) {
            throw new Error(`BUG: Could not set pixel because table is too small`)
        }
        if (!chars || chars.trim().length === 0) {
            chars = ''
        }

        if (!this.renderedPixels[y]) {
            this.renderedPixels[y] = []
        }
        const onScreenPixel = this.renderedPixels[y][x]
        if (!onScreenPixel || onScreenPixel.hex !== hex || onScreenPixel.chars !== chars) {
            this.renderedPixels[y][x] = { hex, chars }

            const { r, g, b, a } = hexToRgb(hex)
            if (a !== null) {
                pixel.setAttribute('style', `background-color: rgba(${r},${g},${b},${a})`)
            } else {
                pixel.setAttribute('style', `background-color: ${hex}`)
                // pixel.textContent = chars
            }
        }
    }

    protected drawCellsAfterRecentering(cells: Iterable<Cellish>, renderScreenDepth: number) {
        for (const cell of cells) {
            this._drawCell(cell, renderScreenDepth)
        }
    }

    protected checkIfCellCanBeDrawnOnScreen(cellStartX: number, cellStartY: number) {
        return true
    }

    protected getMaxSize() {
        // just pick something big for now
        return {
            columns: 1000,
            rows: 1000
        }
    }

    private printMessageLog(a11yMessages: Array<A11Y_MESSAGE<Cellish, GameSprite>>, hasAgain: boolean) {
        if (this.silencedOutput && !this.didPressCauseTick) {
            return
        }
        const GAME_TICK = 'game tick'

        let pendingMessages: string[] = []
        const addMessage = (msg: string, sprites: GameSprite[]) => {
            pendingMessages.push(msg)

            if (this.isCollecting) {
                for (const sprite of sprites) {
                    mapIncrement(this.collectedSprites, sprite)
                }
            }
        }
        const printPendingMessages = () => {
            for (const msg of pendingMessages) {
                const p = document.createElement('p')
                p.textContent = msg
                this.liveLog.append(p)
                if (!this.didPressCauseTick) {
                    this.messagesSincePress++
                }
            }
        }

        if (hasAgain) {
            addMessage(GAME_TICK, [])
        }

        for (const message of a11yMessages) {
            switch (message.type) {
                case A11Y_MESSAGE_TYPE.ADD:
                    for (const sprite of setIntersection(this.usedInMessages, message.sprites)) {
                        addMessage(`Added ${sprite.getName()} @ ${message.cell.rowIndex},${message.cell.colIndex}`, [sprite])
                    }
                    break
                case A11Y_MESSAGE_TYPE.REPLACE:
                    for (const { oldSprite, newSprite } of message.replacements) {
                        if (this.usedInMessages.has(oldSprite)) {
                            if (this.usedInMessages.has(newSprite)) {
                                addMessage(`Replaced ${oldSprite.getName()} with ${newSprite.getName()} @ ${message.cell.rowIndex},${message.cell.colIndex}`, [oldSprite, newSprite])
                            } else {
                                addMessage(`Removed* ${oldSprite.getName()} @ ${message.cell.rowIndex},${message.cell.colIndex}`, [oldSprite])
                            }
                        } else if (this.usedInMessages.has(newSprite)) {
                            addMessage(`Added* ${newSprite.getName()} @ ${message.cell.rowIndex},${message.cell.colIndex}`, [newSprite])
                        }
                    }
                    break
                case A11Y_MESSAGE_TYPE.REMOVE:
                    for (const sprite of setIntersection(this.usedInMessages, message.sprites)) {
                        addMessage(`Removed ${sprite.getName()} @ ${message.cell.rowIndex},${message.cell.colIndex}`, [sprite])
                    }
                    break
                case A11Y_MESSAGE_TYPE.MOVE:
                    addMessage(`Moved ${message.sprite.getName()} ${message.direction} to ${message.newCell.rowIndex},${message.newCell.colIndex}`, [message.sprite])
                    break
                default:
                    throw new Error(`BUG: unsupported a11y message type ${message}`)
            }
        }

        if (this.didPressCauseTick) {
            if (pendingMessages.length > 10) {
                pendingMessages = [...pendingMessages.slice(0, 4), '(truncated messages)', ...pendingMessages.slice(pendingMessages.length - 4, pendingMessages.length)]
            }

        } else if (this.silencedOutput) {
            pendingMessages = []
        } else if (!this.isCollecting && (this.messagesSincePress > 10 || pendingMessages.length > 10)) {
            if (this.collectedSprites.size > 0) {
                // We tried collecting before but it did not seem to work so just go silent
                this.silencedOutput = true
                pendingMessages = [`Things keep changing so switching to a quieter mode`]
            } else {
                // start collecting
                this.isCollecting = true
                this.collectingTickCount = 0
                pendingMessages = [`Many things changed (probably animations). Collecting data for a few ticks to see what to ignore`]
            }
        } else if (this.isCollecting && this.collectingTickCount < 20) {
            pendingMessages = [] // stay silent while collecting
        } else if (this.isCollecting) {
            this.isCollecting = false
            pendingMessages = [`Done collecting. Found ${this.collectedSprites.size} sprites to ignore: ${[...this.collectedSprites.keys()].map((sprite) => sprite.getName()).join(', ')}`]
            this.messagesSincePress = 0
            for (const [sprite, count] of this.collectedSprites) {
                if (count > 4) {
                    this.usedInMessages.delete(sprite)
                }
            }
        }

        printPendingMessages()

        if (this.didPressCauseTick) {
            this.messagesSincePress = 0
        }
    }

    private markAcceptingInput(flag: boolean) {
        if (flag) {
            this.table.setAttribute('data-ps-accepting-input', 'true')
        } else {
            this.inputsProcessed++
            this.table.setAttribute('data-ps-accepting-input', 'false')
        }
        this.table.setAttribute('data-ps-last-input-processed', `${this.inputsProcessed}`)
    }

    private _drawCell(cell: Cellish, renderScreenDepth: number = 0) {
        if (!this.gameData) {
            throw new Error(`BUG: gameData was not set yet`)
        }
        if (!this.hasVisualUi) {
            throw new Error(`BUG: Should not get to this point`)
        }

        // Remove any sprites that do not impact (transitively) the player
        const sprites = cell.getSprites()
        const spritesForDebugging = sprites.filter((s) => this.interactsWithPlayer.has(s))

        const { isOnScreen, cellStartX, cellStartY } = this.cellPosToXY(cell)

        if (!isOnScreen) {
            return // no need to render because it is off-screen
        }

        // Inject the set of sprites for a11y
        const tableRow = this.tableCells[cell.rowIndex - this.windowOffsetRowStart]
        if (!tableRow) {
            throw new Error(`BUG: Should not be trying to draw when there are no table cells`)
        }
        const tableCell = tableRow[cell.colIndex - this.windowOffsetColStart]
        if (!tableCell) {
            throw new Error(`BUG: Should not be trying to draw when there is not a matching table cell`)
        }
        const cellLabel = tableCell.label
        if (!cellLabel) {
            throw new Error(`BUG: Could not find cell in the table: [${cell.rowIndex} - ${this.windowOffsetRowStart}][${cell.colIndex} - ${this.windowOffsetColStart}]`)
        }

        if (process.env.NODE_ENV !== 'production') {
            cellLabel.setAttribute('data-debug-sprites', sprites.map((s) => s.getName()).join(' '))
        }

        if (spritesForDebugging.length > 0) {
            cellLabel.classList.remove('ps-cell-empty')
            const player = this.gameData.getPlayer()
            if (player.getSpritesThatMatch(cell).size > 0) {
                cellLabel.classList.add('ps-player')
            } else {
                cellLabel.classList.remove('ps-player')
            }
            cellLabel.textContent = spritesForDebugging.map((s) => s.getName()).join(', ')
        } else {
            cellLabel.classList.remove('ps-player')
            cellLabel.classList.add('ps-cell-empty')
            cellLabel.textContent = '(empty)' // (empty)
        }

        const pixels: IColor[][] = this.getPixelsForCell(cell)
        pixels.forEach((spriteRow, spriteRowIndex) => {
            spriteRow.forEach((spriteColor: IColor, spriteColIndex) => {
                if (!this.gameData) {
                    throw new Error(`BUG: gameData was not set yet`)
                }
                const x = cellStartX + spriteColIndex
                const y = cellStartY + spriteRowIndex

                let color: Optional<IColor> = null

                if (spriteColor) {
                    if (!spriteColor.isTransparent()) {
                        color = spriteColor
                    } else if (this.gameData.metadata.backgroundColor) {
                        color = this.gameData.metadata.backgroundColor
                    } else {
                        color = null
                    }
                }

                if (color) {
                    const { r, g, b /*,a*/ } = color.toRgb()
                    const hex = color.toHex()
                    let fgHex = null

                    let chars = ' '

                    // Print a debug number which contains the number of sprites in this cell
                    // Change the foreground color to be black if the color is light
                    if (process.env.NODE_ENV === 'development') {
                        if (r > 192 && g > 192 && b > 192) {
                            fgHex = '#000000'
                        } else {
                            fgHex = '#ffffff'
                        }
                        const sprite = spritesForDebugging[spriteRowIndex]
                        if (sprite) {
                            let spriteName = sprite.getName()
                            let wantsToMove

                            switch (cell.getWantsToMove(sprite)) {
                                case RULE_DIRECTION.STATIONARY:
                                    wantsToMove = ''
                                    break
                                case RULE_DIRECTION.UP:
                                    wantsToMove = '^'
                                    break
                                case RULE_DIRECTION.DOWN:
                                    wantsToMove = 'v'
                                    break
                                case RULE_DIRECTION.LEFT:
                                    wantsToMove = '<'
                                    break
                                case RULE_DIRECTION.RIGHT:
                                    wantsToMove = '>'
                                    break
                                case RULE_DIRECTION.ACTION:
                                    wantsToMove = 'X'
                                    break
                                default:
                                    throw new Error(`BUG: Invalid wantsToMove "${cell.getWantsToMove(sprite)}"`)
                            }
                            spriteName = `${wantsToMove}${spriteName}`
                            if (spriteName.length > 10) {
                                const beforeEllipsis = spriteName.substring(0, this.SPRITE_WIDTH)
                                const afterEllipsis = spriteName.substring(spriteName.length - this.SPRITE_WIDTH + 1)
                                spriteName = `${beforeEllipsis}.${afterEllipsis}`
                            }
                            const msg = `${spriteName.substring(spriteColIndex * 2, spriteColIndex * 2 + 2)}`
                            chars = msg.substring(0, 2)
                        }
                        if (spriteRowIndex === this.SPRITE_HEIGHT - 1 && spriteColIndex === this.SPRITE_WIDTH - 1) {
                            if (spritesForDebugging.length > this.SPRITE_WIDTH * 2 - 1) {
                                chars = `${spritesForDebugging.length}`
                            } else {
                                chars = ` ${spritesForDebugging.length}`
                            }
                        }
                    }

                    this.setPixel(x, y, hex, fgHex, chars)

                }
            })
        })
    }
}

export default TableUI