import { Container, Graphics, Text, TextStyle, Sprite, Assets, Texture } from 'pixi.js'
import { CELL_SIZE } from 'shared/board.ts'
import { theme } from '../theme.ts'
import type { Cell } from 'shared/types.ts'
import { isImageSymbol, imageSymbolUrl } from '../binAssets'

const symbolTextureCache = new Map<string, Promise<Texture>>()

function loadSymbolTexture(sym: string): Promise<Texture> {
  let pending = symbolTextureCache.get(sym)
  if (!pending) {
    pending = Assets.load(imageSymbolUrl(sym))
    symbolTextureCache.set(sym, pending)
  }
  return pending
}

export class SymbolRenderer {
  container: Container
  private symbols = new Map<string, Container>()
  customColors: number[] = []
  drawTowers: boolean[] = [true, true]

  constructor() {
    this.container = new Container()
    this.container.sortableChildren = true
  }

  update(
    cells: [string, Cell][],
    _minCellX: number, _minCellY: number,
    _maxCellX: number, _maxCellY: number,
  ): Container[] {
    const keepKeys = new Set<string>()
    const added: Container[] = []

    for (const [key, cell] of cells) {
      keepKeys.add(key)
      if (this.symbols.has(key)) continue

      const [x, y] = key.split(':').map(Number)
      const s = this.createSymbol(cell, x, y)
      this.symbols.set(key, s)
      this.container.addChild(s)
      added.push(s)
    }

    let removed = 0
    for (const [key, symbol] of this.symbols) {
      if (!keepKeys.has(key)) {
        this.container.removeChild(symbol)
        symbol.destroy({ children: true })
        this.symbols.delete(key)
        removed++
      }
    }

    return added
  }

  clear(): void {
    for (const [, symbol] of this.symbols) {
      this.container.removeChild(symbol)
      symbol.destroy({ children: true })
    }
    this.symbols.clear()
  }

  getSymbol(key: string): Container | undefined {
    return this.symbols.get(key)
  }

  private isEmoji(sym: string): boolean {
    const code = sym.codePointAt(0) ?? 0
    return sym.length > 1 || code > 0xFFFF
  }

  private adjustBrightness(color: number, factor: number): number {
    const r = Math.min(255, Math.max(0, Math.round(((color >> 16) & 0xff) * factor)))
    const g = Math.min(255, Math.max(0, Math.round(((color >> 8) & 0xff) * factor)))
    const b = Math.min(255, Math.max(0, Math.round((color & 0xff) * factor)))
    return (r << 16) | (g << 8) | b
  }

  private createSymbol(cell: Cell, gx: number, gy: number): Container {
    const playerColors = this.customColors.length >= 2 ? this.customColors : [theme.player1, theme.player2]
    const color = playerColors[Number(cell.playerId) % 2] ?? 0xffffff
    const sym = cell.symbol || (Number(cell.playerId) === 0 ? 'X' : 'O')
    const drawTower = this.drawTowers[Number(cell.playerId) % 2] !== false

    const lx = gx * CELL_SIZE + CELL_SIZE / 2
    const ly = gy * CELL_SIZE + CELL_SIZE / 2
    const r = CELL_SIZE * 0.38 // slightly larger to fill the grid beautifully

    const g = new Graphics()

    // 2 — Cylinder Side Wall (creates the "tower" extrusion with volumetric shading)
    const wallH = drawTower ? 4 : 0

    // Shading calculations
    const darkColor = this.adjustBrightness(color, 0.7)
    const lightColor = this.adjustBrightness(color, 1.25)

    if (drawTower) {
      // 1 — Deep multi-layered 3D capsule drop shadow (proper cylinder shadow projection)
      const drawCapsuleShadow = (dx: number, dy: number, shadowR: number, alpha: number) => {
        g.circle(dx, dy - wallH, shadowR)
        g.circle(dx, dy, shadowR)
        g.rect(dx - shadowR, dy - wallH, shadowR * 2, wallH)
        g.fill({ color: 0x000000, alpha })
      }

      // Draw outer ambient shadow layer (tighter, soft)
      drawCapsuleShadow(3, 4, r * 1.0, 0.22)
      // Draw middle cast shadow layer
      drawCapsuleShadow(2, 2.5, r * 0.95, 0.40)
      // Draw inner tight contact shadow (very dark, grounded)
      drawCapsuleShadow(1, 1, r * 0.9, 0.65)

      // Bottom cap of the cylinder
      g.circle(0, 0, r)
      g.fill({ color: darkColor })
      // Mid connecting rectangle body
      g.rect(-r, -wallH, r * 2, wallH)
      g.fill({ color: darkColor })
      // Specular highlight on the left side of the cylinder wall (simulating light from top-left)
      g.rect(-r, -wallH, r * 0.4, wallH)
      g.fill({ color: color, alpha: 0.15 })
      // Diffuse shadow on the right side of the cylinder wall
      g.rect(r * 0.6, -wallH, r * 0.4, wallH)
      g.fill({ color: 0x000000, alpha: 0.22 })

      // 3 — Cylinder Top Surface (lighter and polished)
      g.circle(0, -wallH, r)
      g.fill({ color: color })

      // Top face highlight rim (glossy edge)
      g.circle(0, -wallH, r)
      g.stroke({ width: 1.5, color: lightColor, alpha: 0.6 })

      // Inner decorative groove (tactile go-stone/chip details)
      g.circle(0, -wallH, r * 0.78)
      g.stroke({ width: 1.0, color: darkColor, alpha: 0.25 })

      const isEmoji = this.isEmoji(sym)

      // Grounding contact shadow directly on the piece surface under the symbol (only for non-emojis)
      if (!isEmoji) {
        g.circle(0, -wallH + 0.5, r * 0.5)
        g.fill({ color: 0x000000, alpha: 0.15 })
      }
    }

    const isEmoji = this.isEmoji(sym)
    const wrapper = new Container()
    wrapper.addChild(g)

    if (isImageSymbol(sym)) {
      const spriteSize = r * 1.7
      const placeholder = new Sprite()
      placeholder.anchor.set(0.5)
      placeholder.width = spriteSize
      placeholder.height = spriteSize
      placeholder.position.set(0, -wallH)
      wrapper.addChild(placeholder)
      loadSymbolTexture(sym).then(tex => {
        if (placeholder.destroyed) return
        placeholder.texture = tex
        placeholder.width = spriteSize
        placeholder.height = spriteSize
      }).catch(() => {})
    } else {
      // Dynamic High-Contrast Symbol Text
      let textFill: number
      if (drawTower) {
        const rComponent = (color >> 16) & 0xff
        const gComponent = (color >> 8) & 0xff
        const bComponent = color & 0xff
        const brightness = (rComponent * 299 + gComponent * 587 + bComponent * 114) / 1000
        // If the top color is very bright, use a dark theme text color. Otherwise white text.
        textFill = brightness > 175 ? 0x1a1b2e : 0xffffff
      } else {
        // Just the icon: draw it directly in the player's color so it is recognizable
        textFill = color
      }

      const textSize = r * 1.25
      const text = new Text({
        text: sym,
        style: new TextStyle({
          fontSize: isEmoji ? textSize * 1.05 : textSize,
          fill: textFill,
          fontFamily: 'system-ui, sans-serif',
          fontWeight: 'bold',
          dropShadow: {
            color: 0x000000,
            alpha: isEmoji ? 0.75 : 0.45,
            angle: Math.PI / 4,
            distance: isEmoji ? 2.0 : 1.2,
            blur: isEmoji ? 2.5 : 1.0,
          },
        }),
        resolution: 4,
      })

      // Center it visually using its local bounds to correct baseline offsets of emojis
      const bounds = text.getLocalBounds()
      text.pivot.set(
        bounds.x + bounds.width / 2,
        bounds.y + bounds.height / 2
      )
      text.position.set(0, -wallH)
      wrapper.addChild(text)
    }

    wrapper.position.set(lx, ly)

    // Depth sorting — higher Y = closer to viewer
    wrapper.zIndex = ly

    return wrapper
  }
}