var onload = function () {
    var canvas = document.getElementById("renderCanvas");
    var divFps = document.getElementById("fps");
    var mode = "CAMERA";
    
    if (!BABYLON.Engine.isSupported()) {
        document.getElementById("notSupported").className = "";
        return;
    }

    // Babylon
    BABYLON.Engine.ShadersRepository = "/Babylon/Shaders/";
    var engine = new BABYLON.Engine(canvas, true);
    var scene = new BABYLON.Scene(engine);
    var camera = new BABYLON.ArcRotateCamera("Camera", 0, 0, 10, BABYLON.Vector3.Zero(), scene);
    var sun = new BABYLON.PointLight("Omni", new BABYLON.Vector3(20, 100, 2), scene);

    camera.setPosition(new BABYLON.Vector3(20, 40, 20));
    camera.attachControl(canvas);

    // Skybox
    var skybox = BABYLON.Mesh.CreateBox("skyBox", 1000.0, scene);
    var skyboxMaterial = new BABYLON.StandardMaterial("skyBox", scene);
    skyboxMaterial.backFaceCulling = false;
    skyboxMaterial.reflectionTexture = new BABYLON.CubeTexture("Assets/skybox/skybox", scene);
    skyboxMaterial.reflectionTexture.coordinatesMode = BABYLON.Texture.SKYBOX_MODE;
    skyboxMaterial.diffuseColor = new BABYLON.Color3(0, 0, 0);
    skyboxMaterial.specularColor = new BABYLON.Color3(0, 0, 0);
    skybox.material = skyboxMaterial;

    // Grounds
    var ground = BABYLON.Mesh.CreateGroundFromHeightMap("ground", "Assets/heightMap.png", 100, 100, 100, 0, 12, scene, true);
    var groundMaterial = new WORLDMONGER.GroundMaterial("ground", scene, sun);
    ground.material = groundMaterial;
    ground.position.y = -2.0;

    var extraGround = BABYLON.Mesh.CreateGround("extraGround", 1000, 1000, 1, scene, false);
    var extraGroundMaterial = new BABYLON.StandardMaterial("extraGround", scene);
    extraGroundMaterial.diffuseTexture = new BABYLON.Texture("Shaders/Ground/sand.jpg", scene);
    extraGroundMaterial.diffuseTexture.uScale = 60;
    extraGroundMaterial.diffuseTexture.vScale = 60;
    extraGround.position.y = -2.05;
    extraGround.material = extraGroundMaterial;

    // Water
    var water = BABYLON.Mesh.CreateGround("water", 1000, 1000, 1, scene, false);
    var waterMaterial = new WORLDMONGER.WaterMaterial("water", scene, sun);
    waterMaterial.refractionTexture.renderList.push(ground);
    waterMaterial.refractionTexture.renderList.push(extraGround);

    waterMaterial.reflectionTexture.renderList.push(ground);
    waterMaterial.reflectionTexture.renderList.push(skybox);

    water.isPickable = false;
    water.material = waterMaterial;
    
    // Elevation
    var elevationControl = new WORLDMONGER.ElevationControl(ground);
    
    // Bloom
    var blurWidth = 2.0;

    var postProcess0 = new BABYLON.PassPostProcess("Scene copy", 1.0, camera);
    var postProcess1 = new BABYLON.PostProcess("Down sample", "./postprocesses/downsample", ["screenSize", "highlightThreshold"], null, 0.5, camera, BABYLON.Texture.DEFAULT_SAMPLINGMODE);
    postProcess1.onApply = function (effect) {
        effect.setFloat2("screenSize", postProcess1.width, postProcess1.height);
        effect.setFloat("highlightThreshold", 0.85);
    };
    var postProcess2 = new BABYLON.BlurPostProcess("Horizontal blur", new BABYLON.Vector2(1.0, 0), blurWidth, 0.5, camera, BABYLON.Texture.DEFAULT_SAMPLINGMODE);
    var postProcess3 = new BABYLON.BlurPostProcess("Vertical blur", new BABYLON.Vector2(0, 1.0), blurWidth, 0.5, camera, BABYLON.Texture.DEFAULT_SAMPLINGMODE);
    var postProcess4 = new BABYLON.PostProcess("Final compose", "./postprocesses/compose", ["sceneIntensity", "glowIntensity", "highlightIntensity"], ["sceneSampler"], 1, camera);
    postProcess4.onApply = function (effect) {
        effect.setTextureFromPostProcess("sceneSampler", postProcess0);
        effect.setFloat("sceneIntensity", 0.8);
        effect.setFloat("glowIntensity", 0.6);
        effect.setFloat("highlightIntensity", 1.5);
    };

    // Render loop
    var renderFunction = function () {
        if (ground.isReady && ground.subMeshes.length == 1) {
            ground.subdivide(20);    // Subdivide to optimize picking
        }

        // Camera
        if (camera.beta < 0.1)
            camera.beta = 0.1;
        else if (camera.beta > (Math.PI / 2) * 0.92)
            camera.beta = (Math.PI / 2) * 0.92;

        if (camera.radius > 70)
            camera.radius = 70;

        if (camera.radius < 5)
            camera.radius = 5;

        // Fps
        divFps.innerHTML = BABYLON.Tools.GetFps().toFixed() + " fps";

        // Render scene
        scene.render();

        // Animations
        skybox.rotation.y += 0.0001 * scene.getAnimationRatio();
    };

    // Launch render loop
    scene.executeWhenReady(function() {
        engine.runRenderLoop(renderFunction);
    });

    // Resize
    window.addEventListener("resize", function () {
        engine.resize();
    });

    // UI
    var cameraButton = document.getElementById("cameraButton");
    var elevationButton = document.getElementById("elevationButton");
    var digButton = document.getElementById("digButton");
    var help01 = document.getElementById("help01");
    var help02 = document.getElementById("help02");
    
    window.oncontextmenu = function () {
        return false;
    };

    cameraButton.addEventListener("pointerdown", function () {
        if (mode == "CAMERA")
            return;
        camera.attachControl(canvas);
        elevationControl.detachControl(canvas);

        mode = "CAMERA";
        cameraButton.className = "controlButton selected";
        digButton.className = "controlButton";
        elevationButton.className = "controlButton";
    });

    elevationButton.addEventListener("pointerdown", function () {
        help01.className = "help";
        help02.className = "help";

        if (mode == "ELEVATION")
            return;

        if (mode == "CAMERA") {
            camera.detachControl(canvas);
            elevationControl.attachControl(canvas);
        }

        mode = "ELEVATION";
        elevationControl.direction = 1;

        elevationButton.className = "controlButton selected";
        digButton.className = "controlButton";
        cameraButton.className = "controlButton";
    });

    digButton.addEventListener("pointerdown", function () {
        help01.className = "help";
        help02.className = "help";
        
        if (mode == "DIG")
            return;

        if (mode == "CAMERA") {
            camera.detachControl(canvas);
            elevationControl.attachControl(canvas);
        }

        mode = "DIG";
        elevationControl.direction = -1;

        digButton.className = "controlButton selected";
        elevationButton.className = "controlButton";
        cameraButton.className = "controlButton";
    });

    // Sliders
    $("#slider-vertical").slider({
        orientation: "vertical",
        range: "min",
        min: 2,
        max: 15,
        value: 5,
        slide: function (event, ui) {
            elevationControl.radius = ui.value;
        }
    });

    $("#slider-range").slider({
        orientation: "vertical",
        range: true,
        min: 0,
        max: 12,
        values: [0, 11],
        slide: function (event, ui) {
            elevationControl.heightMin = ui.values[0];
            elevationControl.heightMax = ui.values[1];
        }
    });
    
    $("#qualitySlider").slider({
        orientation: "vertical",
        range: "min",
        min: 0,
        max: 3,
        value: 3,
        slide: function (event, ui) {
            switch (ui.value) {
                case 3:
                    waterMaterial.refractionTexture.resize(512, true);
                    waterMaterial.reflectionTexture.resize(512, true);
                    scene.getEngine().setHardwareScalingLevel(1);
                    scene.particlesEnabled = true;
                    scene.postProcessesEnabled = true;
                    break;
                case 2:
                    waterMaterial.refractionTexture.resize(256, true);
                    waterMaterial.reflectionTexture.resize(256, true);
                    scene.getEngine().setHardwareScalingLevel(1);
                    scene.particlesEnabled = false;
                    scene.postProcessesEnabled = false;
                    break;
                case 1:
                    waterMaterial.refractionTexture.resize(256, true);
                    waterMaterial.reflectionTexture.resize(256, true);
                    scene.getEngine().setHardwareScalingLevel(2);
                    scene.particlesEnabled = false;
                    scene.postProcessesEnabled = false;
                    break;
                case 0:
                    waterMaterial.refractionTexture.resize(256, true);
                    waterMaterial.reflectionTexture.resize(256, true);
                    scene.getEngine().setHardwareScalingLevel(3);
                    scene.particlesEnabled = false;
                    scene.postProcessesEnabled = false;
                    break;
            }
        }
    });
    
    help01.className = "help shown";

    setTimeout(function() {
        help01.className = "help";
        help02.className = "help shown";
        setTimeout(function() {
            help02.className = "help";
        }, 5000);
    }, 5000);
};