import { Renderer, UiState } from './engine/renderer'
import { Input } from './ui/input'
import { DomOverlay } from './ui/overlay'
import { Router, Route } from './router'
import { PAGES, PROJECTS_SCENE, RESUME_SCENE } from './data/pages'

const DPR_CAP = 2

export class App {
  private canvas: HTMLCanvasElement
  private renderer = new Renderer()
  private input!: Input
  private overlay!: DomOverlay
  private router = new Router()

  private dpr = 1
  private res = new Float32Array(2)
  private mouse = new Float32Array(2)

  private scene = 0
  private prevScene = -1
  private startTime = 0
  private rafId = 0
  private running = false
  private stemMultipliers = new Float32Array(32)

  constructor(canvas: HTMLCanvasElement) {
    this.canvas = canvas
  }

  async start(): Promise<boolean> {
    this.input = new Input()

    // Build SceneContent[] from PAGES for the overlay
    const scenes = PAGES.map((p) => ({
      title: p.title,
      subtitle: p.subtitle,
      body: p.body,
    }))

    this.overlay = new DomOverlay(scenes, {
      onNavClick: (s) => {
        this.router.navigate(Router.sceneToBasePath(s))
      },
      onButtonClick: () => {
        const next = (this.scene + 1) % 4
        this.router.navigate(Router.sceneToBasePath(next))
      },
      onNavigate: (path) => {
        this.router.navigate(path)
      },
    })

    this.router.onChange((route) => this.applyRoute(route))
    const initial = this.router.start()
    this.applyRoute(initial)
    this.router.replace(Router.sceneToBasePath(this.scene))

    this.resize()
    const ok = await this.renderer.init(this.canvas)
    if (!ok) return false
    this.startTime = performance.now()
    this.running = true
    this.loop()
    return true
  }

  stop(): void {
    this.running = false
    cancelAnimationFrame(this.rafId)
  }

  // ---- routing ----

  private applyRoute(route: Route): void {
    this.scene = route.scene
    this.overlay.setScene(this.scene)

    if (route.scene === PROJECTS_SCENE && 'view' in route) {
      if (route.view === 'category' && 'catId' in route && route.catId) {
        this.overlay.showCategory(route.catId)
      } else if (
        route.view === 'detail' &&
        'catId' in route && route.catId &&
        'projectId' in route && route.projectId
      ) {
        this.overlay.showProjectDetail(route.projectId, route.catId)
      } else {
        this.overlay.showCategoryGrid()
      }
    } else if (route.scene === RESUME_SCENE) {
      this.overlay.showResume()
    }
  }

  // ---- rendering ----

  private resize(): void {
    this.dpr = Math.min(window.devicePixelRatio || 1, DPR_CAP)
    const w = Math.floor(window.innerWidth * this.dpr)
    const h = Math.floor(window.innerHeight * this.dpr)
    if (this.canvas.width !== w || this.canvas.height !== h) {
      this.canvas.width = w
      this.canvas.height = h
      this.res[0] = w
      this.res[1] = h
      if (this.renderer.ready) this.renderer.resize()
    }
  }

  private computeStemMultipliers(time: number): void {
    const sm = this.stemMultipliers
    const colorBase = [0.0, 0.6, 1.2, 2.4]
    const speedBase = [0.0, 0.2, 0.1, 0.15]
    const scene = this.scene

    sm[0] = speedBase[scene]
    sm[2] = colorBase[scene] * 0.2
    sm[3] = 0.3 + 0.3 * Math.sin(time * 0.5)

    sm[4] = colorBase[scene] * 0.4
    sm[8] = 0.1
  }

  private loop = (): void => {
    if (!this.running) return
    this.rafId = requestAnimationFrame(this.loop)

    const now = performance.now()
    const time = (now - this.startTime) / 1000

    this.resize()

    const mx = this.input.x * this.dpr
    const my = this.res[1] - this.input.y * this.dpr
    this.mouse[0] = mx
    this.mouse[1] = my

    if (this.scene !== this.prevScene) {
      this.prevScene = this.scene
    }

    this.computeStemMultipliers(time)

    const state: UiState = {
      resolution: this.res,
      time,
      scene: this.scene,
      mouse: this.mouse,
      stemMultipliers: this.stemMultipliers,
    }
    this.renderer.render(state)
  }
}