/**
 * Storage System takes care loading and linking components and dependencies
 * @param apiSystem GameLib.API.System
 * @param apiUrl
 * @param token
 * @param apiUploadUrl
 * @param onImageLoaded
 * @param onImageProgress
 * @param onImageError
 * @constructor
 */
GameLib.System.Storage = function(
    apiSystem,
    apiUrl,
    token,
    apiUploadUrl,
    onImageLoaded,
    onImageProgress,
    onImageError
) {
    GameLib.System.call(
        this,
        apiSystem
    );

    if (GameLib.Utils.UndefinedOrNull(apiUrl)) {
        console.warn('Need an API URL for a storage system');
        apiUrl = '';
    }
    this.apiUrl = apiUrl;

    if (GameLib.Utils.UndefinedOrNull(token)) {
        token = null;
    }
    this.token = token;

    if (GameLib.Utils.UndefinedOrNull(apiUploadUrl)) {
        console.warn('Need an API Upload URL for a storage system');
        apiUploadUrl = '';
    }
    this.apiUploadUrl = apiUploadUrl;

    if (GameLib.Utils.UndefinedOrNull(onImageLoaded)) {
        onImageLoaded = null;
    }
    this.onImageLoaded = onImageLoaded;

    if (GameLib.Utils.UndefinedOrNull(onImageProgress)) {
        onImageProgress = null;
    }
    this.onImageProgress = onImageProgress;

    if (GameLib.Utils.UndefinedOrNull(onImageError)) {
        onImageError = null;
    }
    this.onImageError = onImageError;

	this.loginSubscription = null;
	this.saveSubscription  = null;
	this.loadSubscription  = null;
	this.loadImageSubscription = null;
    this.meshInstanceCreatedSubscription = null;
    this.lightInstanceCreatedSubscription = null;
    this.sceneInstanceCreatedSubscription = null;
    this.imageInstanceCreatedSubscription = null;
	this.textureInstanceCreatedSubscription = null;
	this.materialInstanceCreatedSubscription = null;

};

GameLib.System.Storage.prototype = Object.create(GameLib.System.prototype);
GameLib.System.Storage.prototype.constructor = GameLib.System.Storage;

GameLib.System.Storage.prototype.start = function() {

	this.loginSubscription = this.subscribe(
		GameLib.Event.LOGGED_IN,
		function(data) {
			this.token = data.token;
		}
	);

	this.saveSubscription = this.subscribe(
		GameLib.Event.SAVE_COMPONENT,
		this.save
	);

	this.loadSubscription = this.subscribe(
		GameLib.Event.LOAD_COMPONENT,
		this.load
	);

	this.loadImageSubscription = this.subscribe(
	    GameLib.Event.LOAD_IMAGE,
        this.loadImage
    );

	this.sceneInstanceCreatedSubscription = this.subscribe(
	    GameLib.Event.SCENE_INSTANCE_CREATED,
        this.sceneInstanceCreated
    );

    this.meshInstanceCreatedSubscription = this.subscribe(
        GameLib.Event.MESH_INSTANCE_CREATED,
        this.meshInstanceCreated
    );

    this.lightInstanceCreatedSubscription = this.subscribe(
        GameLib.Event.LIGHT_INSTANCE_CREATED,
        this.lightInstanceCreated
    );

    this.imageInstanceCreatedSubscription = this.subscribe(
        GameLib.Event.IMAGE_INSTANCE_CREATED,
        this.imageInstanceCreated
    );

	this.textureInstanceCreatedSubscription = this.subscribe(
	    GameLib.Event.TEXTURE_INSTANCE_CREATED,
        this.textureInstanceCreated
    );

    this.materialInstanceCreatedSubscription = this.subscribe(
        GameLib.Event.MATERIAL_INSTANCE_CREATED,
        this.materialInstanceCreated
    );
};

/**
 * 'Saves' data to baseURL
 */
GameLib.System.Storage.prototype.save = function(data) {

    if (typeof XMLHttpRequest === 'undefined') {
        console.log('Implement server side save here');
        return;
    }

    var xhr = new XMLHttpRequest();

    xhr.open(
        'POST',
        this.apiUrl + '/component/create'
    );

    xhr.setRequestHeader("Accept", "application/json");
    xhr.setRequestHeader("Content-Type", "application/json");

    xhr.onreadystatechange = function () {
        if (this.readyState === 4) {
            try {
                var response = JSON.parse(this.responseText)
            } catch (error) {
                GameLib.Event.Emit(
                    GameLib.Event.SAVE_COMPONENT_ERROR,
                    {
                        message: this.responseText
                    }
                )
            }

            if (response.result === 'success') {
                GameLib.Event.Emit(
                    GameLib.Event.COMPONENT_SAVED,
                    {
                        message: response.message || 'Successfully saved the component'
                    }
                )
            } else {
                GameLib.Event.Emit(
                    GameLib.Event.SAVE_COMPONENT_ERROR,
                    {
                        message: response.message || 'The server responded but failed to save the component'
                    }
                )
            }
        }
    };

    xhr.send(JSON.stringify({
        component : data,
        session : this.token
    }));

};

/**
 * 'Loads' data from a url
 */
GameLib.System.Storage.prototype.load = function(data) {

    if (typeof XMLHttpRequest === 'undefined') {
        console.log('Implement server side load here');
        return;
    }

    var xhr = new XMLHttpRequest();

    xhr.open(
        'GET',
		data.url
    );

    xhr.onreadystatechange = function (xhr) {
        return function () {
            if (xhr.readyState === 4) {

                try {
                    var object = JSON.parse(xhr.responseText);
                } catch (error) {
					this.publish(
						GameLib.Event.LOAD_COMPONENT_ERROR,
						{
							error : error
						}
					);
                    return;
                }

                if (object.result !== 'success') {
					this.publish(
						GameLib.Event.LOAD_COMPONENT_ERROR,
						{
							error : object
						}
					);
					return;
                }

                this.publish(
                    GameLib.Event.COMPONENT_LOADED,
                    {
                        response : object,
                        includeDependencies : data.includeDependencies
                    }
                )
            }
        }
    }(xhr).bind(this);

    xhr.send();
};

GameLib.System.Storage.prototype.loadImage = function(data) {

    console.log('loading image : ' + data.image.name);

    var onLoaded = this.onImageLoaded;

    var onProgress = this.onImageProgress;;

    var onError = this.onImageError;

    var image = data.image;

    var url = this.apiUploadUrl + image.path + '?ts=' + Date.now();

    var preflight = new XMLHttpRequest();

    preflight.withCredentials = true;

    preflight.open(
        'OPTIONS',
        url
    );

    preflight.setRequestHeader('Content-Type', 'application/json');

    preflight.onload = function() {

        var xhr = new XMLHttpRequest();

        xhr.withCredentials = true;

        xhr.open('GET', url);

        xhr.setRequestHeader('Content-Type', image.contentType);

        xhr.responseType = 'blob';

        xhr.onload = function() {

            try {
                if (this.response.type !== 'application/json') {
                    var url = window.URL.createObjectURL(this.response);
                } else {
                    if (onError) {
                        onError(image, {message:'Image not found'});
                        return;
                    }
                }
            } catch (error) {
                if (onError) {
                    onError(image, {message:'Image not found'});
                    return;
                }
            }
            var img = document.createElement('img');

            img.onload = function() {

                window.URL.revokeObjectURL(url);

                image.instance = img;
                image.publish(
                    GameLib.Event.IMAGE_INSTANCE_CREATED,
                    {
                        image: image
                    }
                );

                if (onLoaded) {
                    onLoaded(image);
                }
            };

            img.src = url;
        };

        xhr.onprogress = function(progressEvent) {

            var progress = 0;

            if (progressEvent.total !== 0) {
                progress = Number(progressEvent.loaded / progressEvent.total);
                progress *= 100;
            }

            if (onProgress) {
                onProgress(image, progress);
            }

            image.size = progressEvent.total;
        };

        xhr.onerror = function(error) {
            console.warn('image load failed for image ' + image.name);
            if (onError) {
                onError(image, error)
            }
        };

        xhr.send();
    };

    preflight.onerror = function(error) {
        console.warn('image pre-flight request failed for image ' + image.name);
        if (onError) {
            onError(image, error);
        }
    };

    preflight.send();
};

GameLib.System.Storage.prototype.meshInstanceCreated = function(data) {

    var scenes = GameLib.EntityManager.Instance.queryComponents([GameLib.D3.Scene]);

    scenes.map(function(scene){
        if (data.mesh.parentScene === scene) {
            scene.addObject(data.mesh);
        }
    });

};

GameLib.System.Storage.prototype.lightInstanceCreated = function(data) {

    var scenes = GameLib.EntityManager.Instance.queryComponents([GameLib.D3.Scene]);

    scenes.map(function(scene){
        if (data.light.parentScene === scene) {
            scene.addObject(data.light);
        }
    });

};

GameLib.System.Storage.prototype.sceneInstanceCreated = function(data) {

    var scene = data.scene;

    scene.images.map(
        function(image){
            GameLib.Event.Emit(
                GameLib.Event.LOAD_IMAGE,
                {
                    onLoaded : function(image) {
                        if (this.onImageLoaded) {
                            this.onImageLoaded(image);
                        }
                    },
                    onProgress : function(image, progress) {
                        if (this.onImageProgress) {
                            this.onImageProgress(image, progress);
                        }
                    },
                    onError : function(image, error) {
                        if (this.onImageError) {
                            this.onImageError(image, error);
                        }
                    },
                    image : image
                }
            );
        }.bind(this)
    );

    /**
     * Add all meshes and lights
     */
    var object = GameLib.EntityManager.Instance.queryComponents([
        GameLib.D3.Mesh,
        GameLib.D3.Light
    ]);
    object.map(function(object){
        if (
            object.parentScene === scene
        ) {
            scene.addObject(object);
        }
    });

};

GameLib.System.Storage.prototype.imageInstanceCreated = function(data) {

    var textures = GameLib.EntityManager.Instance.queryComponents([GameLib.D3.Texture]);

    textures.map(
        function(texture) {
            /**
             * Only work with images that belong to this texture
             */
            if (
                texture.image === data.image
            ) {
                /**
                 * Update instance, if already an instance
                 */
                if (texture.instance) {
                    texture.updateInstance();
                    GameLib.Event.Emit(
                        GameLib.Event.TEXTURE_INSTANCE_UPDATED,
                        {
                            texture : texture
                        }
                    )
                } else {
                    /**
                     * Create a new instance
                     */
                    texture.instance = texture.createInstance();
                    GameLib.Event.Emit(
                        GameLib.Event.TEXTURE_INSTANCE_CREATED,
                        {
                            texture : texture
                        }
                    )
                }
            }
        }
    );
};

GameLib.System.Storage.prototype.textureInstanceCreated = function(data) {

    var materials = GameLib.EntityManager.Instance.queryComponents([GameLib.D3.Material]);

    materials.map(

        function(material) {

            if (!material.instance) {
                console.log('No material instance for ' + material.name);
                return;
            }

            var modified = false;

            /**
             * We also need to check if the image of the texture is assigned -
             * if not we should disable the map
             */
            if (material.alphaMap === data.texture) {

                if (data.texture.image) {
                    material.instance.alphaMap = data.texture.instance;
                } else {
                    material.instance.alphaMap = null;
                }

                modified = true;
            }
            if (material.aoMap === data.texture) {

                if (data.texture.image) {
                    material.instance.aoMap = data.texture.instance;
                } else {
                    material.instance.aoMap = null;
                }
                modified = true;
            }
            if (material.bumpMap === data.texture) {

                if (data.texture.image) {
                    material.instance.bumpMap = data.texture.instance;
                } else {
                    material.instance.bumpMap = null;
                }
                modified = true;
            }
            if (material.diffuseMap === data.texture) {

                if (data.texture.image) {
                    material.instance.map = data.texture.instance;
                } else {
                    material.instance.map = null;
                }
                modified = true;
            }
            if (material.displacementMap === data.texture) {

                if (data.texture.image) {
                    material.instance.displacementMap = data.texture.instance;
                } else {
                    material.instance.displacementMap = null;
                }
                modified = true;
            }
            if (material.emissiveMap === data.texture) {

                if (data.texture.image) {
                    material.instance.emissiveMap = data.texture.instance;
                } else {
                    material.instance.emissiveMap = null;
                }
                modified = true;
            }
            if (material.environmentMap === data.texture) {

                if (data.texture.image) {
                    material.instance.envMap = data.texture.instance;
                } else {
                    material.instance.envMap = null;
                }
                modified = true;
            }
            if (material.lightMap === data.texture) {

                if (data.texture.image) {
                    material.instance.lightMap = data.texture.instance;
                } else {
                    material.instance.lightMap = null;
                }
                modified = true;
            }
            if (material.metalnessMap === data.texture) {

                if (data.texture.image) {
                    material.instance.metalnessMap = data.texture.instance;
                } else {
                    material.instance.metalnessMap = null;
                }
                modified = true;
            }
            if (material.normalMap === data.texture) {

                if (data.texture.image) {
                    material.instance.normalMap = data.texture.instance;
                } else {
                    material.instance.normalMap = null;
                }
                modified = true;
            }
            if (material.roughnessMap === data.texture) {

                if (data.texture.image) {
                    material.instance.roughnessMap = data.texture.instance;
                } else {
                    material.instance.roughnessMap = null;
                }
                modified = true;
            }
            if (material.specularMap === data.texture) {

                if (data.texture.image) {
                    material.instance.specularMap = data.texture.instance;
                } else {
                    material.instance.specularMap = null;
                }
                modified = true;
            }

            if (modified) {
                material.updateInstance();
                GameLib.Event.Emit(
                    GameLib.Event.MATERIAL_INSTANCE_UPDATED,
                    {
                        material : material
                    }
                )
            }
        }
    );
};

GameLib.System.Storage.prototype.materialInstanceCreated = function(data) {

    var meshes = GameLib.EntityManager.Instance.queryComponents([GameLib.D3.Mesh]);

    meshes.map(function(mesh){

        if (!mesh.instance) {
            return;
        }

        /**
         * Only work with materials assigned to us
         */
        if (mesh.materials[0] !== data.material) {
            return;
        }

        if (mesh.instance.material === data.material.instance) {
            //mesh.instance.geometry.uvsNeedUpdate = true;
            return;
        }

        if (mesh.materials[0] === data.material) {

            if (mesh.instance.material !== data.material.instance) {
                mesh.instance.material = data.material.instance;
            }

            //mesh.instance.geometry.uvsNeedUpdate = true;
        }
    });

};

GameLib.System.Storage.prototype.stop = function() {
    this.loginSubscription.remove();
	this.loadSubscription.remove();
	this.saveSubscription.remove();
    this.loadImageSubscription.remove();
    this.meshInstanceCreatedSubscription.remove();
    this.lightInstanceCreatedSubscription.remove();
    this.sceneInstanceCreatedSubscription.remove();
    this.imageInstanceCreatedSubscription.remove();
    this.textureInstanceCreatedSubscription.remove();
    this.materialInstanceCreatedSubscription.remove();
};