import Engine from './engine'
import Camera from './engine/camera'
import Resource from './engine/resource'
import loadMesh from './engine/mesh/loader'

import { Environment } from './engine/environment'
import { LODTerrain } from './engine/components/terrain/lod'
import { Skybox } from './engine/components/skybox'
import { WaterTile } from './engine/components/water'
import { SimplexHeightMap } from './engine/components/terrain/heightmap'
import { Material, Texture } from './engine/mesh/material'
import { GUIRenderer, GUIImage, Dim4 } from './engine/gui'
import { FontRenderer, GUIText, Font } from './engine/gui/font'

let game = Engine
let env = new Environment()
let gui = new GUIRenderer()
let fnt = new FontRenderer()

async function pipeline () {
  let entity = await loadMesh(game.gl, 'test')
  let shader = await game.shaders.createShaderFromFiles(game.gl, 'basic', false)
  let terrainShader = await game.shaders.createShaderFromFiles(game.gl, 'terrain', false)
  let skyboxShader = await game.shaders.createShaderFromFiles(game.gl, 'skybox', false)
  let waterShader = await game.shaders.createShaderFromFiles(game.gl, 'water', false)

  entity.setRotation([0.0, 0.0, -90.0])

  let water = new WaterTile([100.0, 0.0, 100.0], 100.0)
  water.initialize(game.gl)
  await water.useDUDV(game.gl, 'dudv')
  await water.useNormalMap(game.gl, 'normalmap')

  let arialFont = await Font.fromFile('arial')
  await arialFont.loadTextures(game.gl)

  // Initialize GUI
  await gui.initialize(game)
  await fnt.initialize(game)

  let itms = [
    new GUIImage(await Texture.createTexture2D(game.gl, await Resource.loadImage('noisy.png'), false, game.gl.LINEAR),
      new Dim4(-0.9, 0.0, 0.9, 0.0), new Dim4(0.1, 0.0, 0.1, 0.0))
  ]
  // Nesting test
  itms[0].addChild(new GUIText('this is example text!\nmulti line!', arialFont, 1.5, new Dim4(0.1, 0.0, -0.1, 0.0), new Dim4(1.0, 0.0, 0.3, 0.0), false))
  itms[0].children[0].color = [1.0, 0.0, 0.2]
  itms[0].updateTransform()

  // Create a height map based on OpenSimplex noise
  let hmap = new SimplexHeightMap(1, 1, 256, 50)

  // Create a terrain instance
  let terrain = new LODTerrain([0.0, 0.0, 0.0], 1024, 1024, 850, 4)

  // Terrain material
  let material = new Material(['grass-1024.jpg'])
  await material.loadTextures(game.gl)

  // test code
  for (let i in entity.children) {
    entity.children[i].mesh.material = material
  }

  // Set generator and material for terrain
  terrain.setGenerator(hmap)
  terrain.setMaterial(material)

  // Create and initialize the camera
  let cam = new Camera([-32.0, 100.0, -32.0], [0.8, -0.6, 0.0])
  cam.updateProjection(game.gl)

  // Create skybox
  let skybox = new Skybox('skybox', cam.farPlane / 2)

  // Load textures and generate a mesh
  await skybox.initialize(game.gl)

  itms.push(new GUIImage(water.fbos.reflectionTexture, new Dim4(-0.9, 0.0, 0.9, 0.0), new Dim4(0.1, 0.0, 0.1, 0.0)))
  itms.push(new GUIImage(water.fbos.refractionTexture, new Dim4(-0.3, 0.0, 0.9, 0.0), new Dim4(0.1, 0.0, 0.1, 0.0)))

  // Update function for camera and terrain
  game.addUpdateFunction(function (dt) {
    if (game.input.isDown('w')) {
      cam.processKeyboard(0, dt)
    } else if (game.input.isDown('s')) {
      cam.processKeyboard(1, dt)
    }

    if (game.input.isDown('a')) {
      cam.processKeyboard(2, dt)
    } else if (game.input.isDown('d')) {
      cam.processKeyboard(3, dt)
    }

    // Panning
    if (game.input.mouseMoved && game.input.mouse.btn0) {
      cam.processMouseMove(game.input.mouseOffset)
    }

    // Update detail levels
    terrain.update(game.gl, cam)
    terrain.updateLODMesh(game.gl)
  })

  function drawEverything (gl) {
    game.prepare()

    // Use terrain shader
    terrainShader.use(gl)

    // Set environment variables in shader
    env.draw(gl, terrainShader)

    // Set the viewport uniforms
    cam.draw(gl, terrainShader)

    // Draw terrain
    terrain.draw(gl, terrainShader)

    shader.use(gl)
    cam.draw(gl, shader)
    entity.draw(gl, shader)

    // Draw the skybox
    skyboxShader.use(gl)
    skybox.draw(gl, skyboxShader, cam)
  }

  // Render function for the triangle
  game.addRenderFunction(function (gl) {
    water.reflect(gl, cam, drawEverything)
    water.refract(gl, cam, drawEverything)

    drawEverything(gl)

    waterShader.use(gl)
    cam.draw(gl, waterShader)
    water.draw(gl, waterShader, cam, env.sun)

    // Draw GUIs
    gui.draw(gl, cam, itms)
    fnt.draw(gl, cam, itms)
  })

  game.startGameLoop()
}

// Start the game, catch any errors thrown
pipeline().catch(function (e) {
  console.error(e)
})