// viewer.js
// ==============================

async function loadImageAsTexture(url, app) {
    return new Promise((resolve, reject) => {
        const img = new window.Image();
        img.crossOrigin = "anonymous";
        img.onload = function() {
            const tex = new pc.Texture(app.graphicsDevice, {
                width: img.width,
                height: img.height,
                format: pc.PIXELFORMAT_R8_G8_B8_A8,
            });
            tex.setSource(img);
            resolve(tex);
        };
        img.onerror = reject;
        img.src = url;
    });
}  


// --- Patch all window.Image to force crossOrigin="anonymous" ---
(function() {
  const OriginalImage = window.Image;
  window.Image = function(...args) {
    const img = new OriginalImage(...args);
    img.crossOrigin = "anonymous";
    // Optionally log image loading for debugging
    return img;
  };
})();

function hexToRgbaArray(hex) {
  try {
    hex = hex.replace("#", "");
    if (hex.length === 6) hex += "FF";
    if (hex.length !== 8) return [1, 1, 1, 1];
    const num = parseInt(hex, 16);
    return [
      ((num >> 24) & 0xFF) / 255,
      ((num >> 16) & 0xFF) / 255,
      ((num >> 8)  & 0xFF) / 255,
      (num & 0xFF) / 255
    ];
  } catch (e) {
    alert("hexToRgbaArray error: " + e);
    return [1, 1, 1, 1];
  }
}

// ----- Utility: Recursive scene traversal -----
function traverse(entity, callback) {
    callback(entity);
    if (entity.children) {
        entity.children.forEach(child => traverse(child, callback));
    }
}

let pc;
export let app = null;
let cameraEntity = null;
let modelEntity = null;
let viewerInitialized = false;
let resizeObserver = null;

let chosenCameraX, chosenCameraY, chosenCameraZ;
let minZoom, maxZoom, minAngle, maxAngle, minAzimuth, maxAzimuth, minPivotY, minY;
let modelX, modelY, modelZ, modelScale, modelRotationX, modelRotationY, modelRotationZ;

let presentoirScaleX, presentoirScaleY, presentoirScaleZ;

let sogsUrl, glbUrl, presentoirUrl;

let color_bg_hex, color_bg, espace_expo_bool;

export async function initializeViewer(config, instanceId) {
  if (viewerInitialized) return;

  const isIOS = /iPad|iPhone|iPod/.test(navigator.userAgent);
  const isMobile = isIOS || /Android/i.test(navigator.userAgent);

  //prends les differents arguments de config.json
  sogsUrl = config.sogs_json_url;
  glbUrl = (config.glb_url !== undefined) ? config.glb_url : "https://huggingface.co/datasets/MikaFil/viewer_gs/resolve/main/ressources/espace_expo/sol_blanc_2.glb";
  presentoirUrl = (config.presentoir_url !== undefined) ? config.presentoir_url : "https://huggingface.co/datasets/MikaFil/viewer_gs/resolve/main/ressources/espace_expo/sol_blanc_2.glb";
  minZoom = parseFloat(config.minZoom || "1");
  maxZoom = parseFloat(config.maxZoom || "20");
  minAngle = parseFloat(config.minAngle || "-45");
  maxAngle = parseFloat(config.maxAngle || "90");
  minAzimuth = (config.minAzimuth !== undefined) ? parseFloat(config.minAzimuth) : -360;
  maxAzimuth = (config.maxAzimuth !== undefined) ? parseFloat(config.maxAzimuth) : 360;
  minPivotY = parseFloat(config.minPivotY || "0");
  minY = (config.minY !== undefined) ? parseFloat(config.minY) : 0;

  modelX = (config.modelX !== undefined) ? parseFloat(config.modelX) : 0;
  modelY = (config.modelY !== undefined) ? parseFloat(config.modelY) : 0;
  modelZ = (config.modelZ !== undefined) ? parseFloat(config.modelZ) : 0;
  modelScale = (config.modelScale !== undefined) ? parseFloat(config.modelScale) : 1;
  modelRotationX = (config.modelRotationX !== undefined) ? parseFloat(config.modelRotationX) : 0;
  modelRotationY = (config.modelRotationY !== undefined) ? parseFloat(config.modelRotationY) : 0;
  modelRotationZ = (config.modelRotationZ !== undefined) ? parseFloat(config.modelRotationZ) : 0;

  presentoirScaleX = (config.presentoirScaleX !== undefined) ? parseFloat(config.presentoirScaleX) : 0;
  presentoirScaleY = (config.presentoirScaleY !== undefined) ? parseFloat(config.presentoirScaleY) : 0;
  presentoirScaleZ = (config.presentoirScaleZ !== undefined) ? parseFloat(config.presentoirScaleZ) : 0; 

  const cameraX = (config.cameraX !== undefined) ? parseFloat(config.cameraX) : 0;
  const cameraY = (config.cameraY !== undefined) ? parseFloat(config.cameraY) : 2;
  const cameraZ = (config.cameraZ !== undefined) ? parseFloat(config.cameraZ) : 5;
  const cameraXPhone = (config.cameraXPhone !== undefined) ? parseFloat(config.cameraXPhone) : cameraX;
  const cameraYPhone = (config.cameraYPhone !== undefined) ? parseFloat(config.cameraYPhone) : cameraY;
  const cameraZPhone = (config.cameraZPhone !== undefined) ? parseFloat(config.cameraZPhone) : (cameraZ * 1.5);

  color_bg_hex = (config.canvas_background !== undefined) ? config.canvas_background : "#FFFFFF";
  espace_expo_bool = (config.espace_expo_bool !== undefined) ? config.espace_expo_bool : false;
  color_bg = hexToRgbaArray(color_bg_hex);

  chosenCameraX = isMobile ? cameraXPhone : cameraX;
  chosenCameraY = isMobile ? cameraYPhone : cameraY;
  chosenCameraZ = isMobile ? cameraZPhone : cameraZ;

  //cree le nouveau canva (instanceId est une valeur aléatoire pour gérer plusieurs canvas sur la meme page)
  const canvasId = 'canvas-' + instanceId;
  const progressDialog = document.getElementById('progress-dialog-' + instanceId);
  const progressIndicator = document.getElementById('progress-indicator-' + instanceId);
  const viewerContainer = document.getElementById('viewer-container-' + instanceId);

  let oldCanvas = document.getElementById(canvasId);
  if (oldCanvas) oldCanvas.remove();

  const canvas = document.createElement('canvas');
  canvas.id = canvasId;
  canvas.className = 'ply-canvas';
  canvas.style.width = "100%";
  canvas.style.height = "100%";
  canvas.setAttribute('tabindex', '0');
  viewerContainer.insertBefore(canvas, progressDialog);

  canvas.style.touchAction = "none";
  canvas.style.webkitTouchCallout = "none";
  canvas.addEventListener('gesturestart', e => e.preventDefault());
  canvas.addEventListener('gesturechange', e => e.preventDefault());
  canvas.addEventListener('gestureend', e => e.preventDefault());
  canvas.addEventListener('dblclick', e => e.preventDefault());
  canvas.addEventListener('touchstart', e => { if (e.touches.length > 1) e.preventDefault(); }, { passive: false });
  canvas.addEventListener('wheel', (e) => { e.preventDefault(); }, { passive: false });

  progressDialog.style.display = 'block';

  if (!pc) {
    pc = await import("https://esm.run/playcanvas");
    window.pc = pc;
  }

  // Create app first
  const device = await pc.createGraphicsDevice(canvas, {
    deviceTypes: ["webgl2"],
    glslangUrl: "https://playcanvas.vercel.app/static/lib/glslang/glslang.js",
    twgslUrl: "https://playcanvas.vercel.app/static/lib/twgsl/twgsl.js",
    antialias: false
  });
  device.maxPixelRatio = Math.min(window.devicePixelRatio, 2);

  const opts = new pc.AppOptions();
  opts.graphicsDevice = device;
  opts.mouse = new pc.Mouse(canvas);
  opts.touch = new pc.TouchDevice(canvas);
  opts.componentSystems = [
    pc.RenderComponentSystem,
    pc.CameraComponentSystem,
    pc.LightComponentSystem,
    pc.ScriptComponentSystem,
    pc.GSplatComponentSystem,
    pc.CollisionComponentSystem,
    pc.RigidbodyComponentSystem
  ];
  opts.resourceHandlers = [
    pc.TextureHandler,
    pc.ContainerHandler,
    pc.ScriptHandler,
    pc.GSplatHandler
  ];

  app = new pc.Application(canvas, opts);
  app.setCanvasFillMode(pc.FILLMODE_NONE);
  app.setCanvasResolution(pc.RESOLUTION_AUTO);

  resizeObserver = new ResizeObserver(entries => {
    entries.forEach(entry => {
      app.resizeCanvas(entry.contentRect.width, entry.contentRect.height);
    });
  });
  resizeObserver.observe(viewerContainer);

  window.addEventListener('resize', () => app.resizeCanvas(viewerContainer.clientWidth, viewerContainer.clientHeight));
  app.on('destroy', () => resizeObserver.disconnect());

  // Assets after app exists
  const assets = {
    sogs: new pc.Asset('gsplat', 'gsplat', { url: sogsUrl }),
    orbit: new pc.Asset('script', 'script', { url: "https://mikafil-viewer-gs.static.hf.space/orbit-camera.js" }),
    glb: new pc.Asset('glb', 'container', { url: glbUrl }),
    presentoir: new pc.Asset('presentoir', 'container', {url: presentoirUrl}),
  };


  // /!\ ======================================== /!\
  const grilleTex = await loadImageAsTexture('https://huggingface.co/datasets/MikaFil/viewer_gs/resolve/main/ressources/textures/grille_cadrillee_4k.jpg', app);
  // /!\ ======================================== /!\
  for (const key in assets) app.assets.add(assets[key]);

   const loader = new pc.AssetListLoader(Object.values(assets), app.assets);
  loader.load(() => {
    app.start();
    progressDialog.style.display = 'none';
    
    modelEntity = new pc.Entity('model');
    modelEntity.addComponent('gsplat', { asset: assets.sogs });
    modelEntity.setLocalPosition(modelX, modelY, modelZ);
    modelEntity.setLocalEulerAngles(modelRotationX, modelRotationY, modelRotationZ);
    modelEntity.setLocalScale(modelScale, modelScale, modelScale);
    app.root.addChild(modelEntity);

    const glbEntity = assets.glb.resource.instantiateRenderEntity();
    app.root.addChild(glbEntity);

    const presentoirEntity =assets.presentoir.resource.instantiateRenderEntity();
    presentoirEntity.setLocalScale(presentoirScaleX, presentoirScaleY, presentoirScaleZ);
    app.root.addChild(presentoirEntity);

    if(!espace_expo_bool){

      let matSol = new pc.StandardMaterial();
      matSol.blendType = pc.BLEND_NONE;
      matSol.emissive = new pc.Color(color_bg);
      matSol.emissiveIntensity = 1;
      matSol.emissiveMap = grilleTex;
      matSol.useLighting = false;
      matSol.update();

      traverse(presentoirEntity, node => {
        if (node.render && node.render.meshInstances) {
          for (let mi of node.render.meshInstances) {
              mi.material = matSol;
          }
        }
      });

      traverse(glbEntity, node => {
        if (node.render && node.render.meshInstances) {
          for (let mi of node.render.meshInstances) {
              mi.material = matSol;
          }
        }
      });
    }
    
    cameraEntity = new pc.Entity('camera');
    cameraEntity.addComponent('camera', 
      { clearColor: new pc.Color(color_bg),
        nearClip: 0.001,
        farClip: 100
      });
    cameraEntity.setPosition(chosenCameraX, chosenCameraY, chosenCameraZ);
    cameraEntity.lookAt(modelEntity.getPosition());
    cameraEntity.addComponent('script');
    cameraEntity.script.create('orbitCamera', {
      attributes: {
        focusEntity: modelEntity,
        inertiaFactor: 0.2,
        distanceMax: maxZoom,
        distanceMin: minZoom,
        pitchAngleMax: maxAngle,
        pitchAngleMin: minAngle,
        yawAngleMax: maxAzimuth,
        yawAngleMin: minAzimuth,
        minY: minY,
        frameOnStart: false
      }
    });
    cameraEntity.script.create('orbitCameraInputMouse');
    cameraEntity.script.create('orbitCameraInputTouch');
    app.root.addChild(cameraEntity);

    app.resizeCanvas(viewerContainer.clientWidth, viewerContainer.clientHeight);
    app.once('update', () => resetViewerCamera());

    // Tooltips supported if tooltips_url set
    try {
      if (config.tooltips_url) {
        import('./tooltips.js').then(tooltipsModule => {
          tooltipsModule.initializeTooltips({
            app,
            cameraEntity,
            modelEntity,
            tooltipsUrl: config.tooltips_url,
            defaultVisible: !!config.showTooltipsDefault,
            moveDuration: config.tooltipMoveDuration || 0.6
          });
        }).catch(e => {
          // Tooltips optional: fail silently if missing
        });
      }
    } catch (e) {
      // Tooltips optional, fail silently
    }

    viewerInitialized = true;
  });
}

export function resetViewerCamera() {
  try {
    if (!cameraEntity || !modelEntity || !app) return;
    const orbitCam = cameraEntity.script.orbitCamera;
    if (!orbitCam) return;

    const modelPos = modelEntity.getPosition();
    const tempEnt = new pc.Entity();
    tempEnt.setPosition(chosenCameraX, chosenCameraY, chosenCameraZ);
    tempEnt.lookAt(modelPos);

    const dist = new pc.Vec3().sub2(
      new pc.Vec3(chosenCameraX, chosenCameraY, chosenCameraZ),
      modelPos
    ).length();

    cameraEntity.setPosition(chosenCameraX, chosenCameraY, chosenCameraZ);
    cameraEntity.lookAt(modelPos);

    orbitCam.pivotPoint = modelPos.clone();
    orbitCam._targetDistance = dist;
    orbitCam._distance = dist;

    const rot = tempEnt.getRotation();
    const fwd = new pc.Vec3();
    rot.transformVector(pc.Vec3.FORWARD, fwd);

    const yaw = Math.atan2(-fwd.x, -fwd.z) * pc.math.RAD_TO_DEG;
    const yawQuat = new pc.Quat().setFromEulerAngles(0, -yaw, 0);
    const rotNoYaw = new pc.Quat().mul2(yawQuat, rot);
    const fNoYaw = new pc.Vec3();
    rotNoYaw.transformVector(pc.Vec3.FORWARD, fNoYaw);
    const pitch = Math.atan2(fNoYaw.y, -fNoYaw.z) * pc.math.RAD_TO_DEG;

    orbitCam._targetYaw = yaw;
    orbitCam._yaw = yaw;
    orbitCam._targetPitch = pitch;
    orbitCam._pitch = pitch;
    if (orbitCam._updatePosition) orbitCam._updatePosition();

    tempEnt.destroy();
  } catch (e) {
    console.error("[VIEWER DEBUG] resetViewerCamera error", e);
  }
}