main.js

'use strict';

const DEBUG = false;
const DEBUG_ERRORS = true;
const DEBUG_SVG = false;

if (DEBUG) {
    console.log('inside of the aminogfx main.js');
}

//load native module
const binary = require('node-pre-gyp');
const path = require('path');
const binding_path = binary.find(path.resolve(path.join(__dirname, 'package.json')));
const native = require(binding_path);

let request = require('request');
const fs = require('fs');
const sharp = require('sharp');

const packageInfo = require('./package.json');

/**
 * Use custom request handler.
 *
 * Has to implement handler(opts, callback) and to support abort().
 */
function setRequestHandler(handler) {
    request = handler;
}

exports.setRequestHandler = setRequestHandler;

/**
 * Get the request handler.
 */
function getRequestHandler() {
    return request;
}

exports.getRequestHandler = getRequestHandler;

//
//  AminoGfx
//
const AminoGfx = native.AminoGfx;

/**
 * Initialize AminoGfx instance.
 */
AminoGfx.prototype.init = function () {
    if (DEBUG) {
        console.log('AminoGfx.init()');
    }

    //initialize bindings
    this.amino = this;

    makeProps(this, {
        //position (auto set)
        x: -1,
        y: -1,

        //QHD size
        w: 640,
        h: 360,

        //color
        opacity: 1,
        fill: '#000000',
        r: 0,
        g: 0,
        b: 0,

        //title
        title: 'AminoGfx OpenGL',

        //stats
        showFPS: true //opt-out
    });

    this.fill.watch(watchFill);

    //root wrapper
    this.setRoot(this.createGroup());

    //input handler
    this.inputHandler = input.createEventHandler(this);

    //process handler
    /*
    process.on('SIGINT', () => {
        console.log('-> CTRL-C');

        //stop
        process.exit();
    });
    */
};

/**
 * Fill value has changed.
 */
function watchFill(value, prop, obj) {
    const color = parseRGBString(value);

    obj.r(color.r);
    obj.g(color.g);
    obj.b(color.b);
}

/**
 * Convert RGB expression to object.
 *
 * Supports:
 *
 *  - hex strings
 *  - array: r, g, b (0..1)
 *  - objects: r, g, b (0..1)
 */
function parseRGBString(fill) {
    if (typeof fill === 'string') {
        //strip off any leading #
        if (fill.substring(0, 1) === '#') {
            fill = fill.substring(1);
        }

        //pull out the components
        const r = parseInt(fill.substring(0, 2), 16);
        const g = parseInt(fill.substring(2, 4), 16);
        const b = parseInt(fill.substring(4, 6), 16);

        return {
            r: r / 255,
            g: g / 255,
            b: b / 255
        };
    } else if (Array.isArray(fill)) {
        return {
            r: fill[0],
            g: fill[1],
            b: fill[2]
        };
    }

    return fill;
}

/**
 * Start renderer.
 */
AminoGfx.prototype.start = function (done) {
    const promise = new Promise((resolve, reject) => {
        //pass to native code
        this._start(err => {
            if (err) {
                reject(err);
                return;
            }

            //runtime info
            this.runtime.aminogfx = packageInfo.version;

            //ready
            resolve(this);

            //check root
            if (!this.root) {
                throw new Error('Missing root!');
            }
        });
    });

    //promise version
    if (arguments.length === 0) {
        return promise;
    }

    //callback version
    promise.then(() => {
        //ready (Note: this points to the instance)
        done.call(this, null);
    }).catch(err => {
        done.call(this, err);
    });
};

/**
 * Set the root node.
 */
AminoGfx.prototype.setRoot = function (root) {
    this.root = root;

    this._setRoot(root);
};

/**
 * Get the root node.
 */
AminoGfx.prototype.getRoot = function () {
    return this.root;
};

/**
 * Create group element.
 */
AminoGfx.prototype.createGroup = function (attrs) {
    const group = new AminoGfx.Group(this);

    if (attrs) {
        group.attr(attrs);
    }

    return group;
};

/**
 * Create rect element.
 */
AminoGfx.prototype.createRect = function (attrs) {
    const rect = new AminoGfx.Rect(this);

    if (attrs) {
        rect.attr(attrs);
    }

    return rect;
};

/**
 * Create image view element.
 */
AminoGfx.prototype.createImageView = function (attrs) {
    const iv = new AminoGfx.ImageView(this);

    if (attrs) {
        iv.attr(attrs);
    }

    return iv;
};

/**
 * Create pixel view element.
 */
AminoGfx.prototype.createPixelView = function (attrs) {
    const pv = new AminoGfx.PixelView(this);

    if (attrs) {
        pv.attr(attrs);
    }

    return pv;
};

/**
 * Create texture element.
 */
AminoGfx.prototype.createTexture = function (attrs) {
    const texture = new AminoGfx.Texture(this);

    if (attrs) {
        texture.attr(attrs);
    }

    return texture;
};

/**
 * Create polygon element.
 */
AminoGfx.prototype.createPolygon = function (attrs) {
    const polygon = new AminoGfx.Polygon(this);

    if (attrs) {
        polygon.attr(attrs);
    }

    return polygon;
};

/**
 * Create model element.
 */
AminoGfx.prototype.createModel = function (attrs) {
    const model = new AminoGfx.Model(this);

    if (attrs) {
        model.attr(attrs);
    }

    return model;
};

/**
 * Create circle element.
 */
AminoGfx.prototype.createCircle = function (attrs) {
    const circle = new AminoGfx.Circle(this);

    if (attrs) {
        circle.attr(attrs);
    }

    return circle;
};

/**
 * Create text element.
 */
AminoGfx.prototype.createText = function (attrs) {
    const text = new AminoGfx.Text(this);

    if (attrs) {
        text.attr(attrs);
    }

    return text;
};

/**
 * Handle an event.
 */
AminoGfx.prototype.handleEvent = function (evt) {
    //debug
    //console.log('Event: ' + JSON.stringify(evt));

    //add timestamp
    evt.time = Date.now();

    //pass to event processor
    this.inputHandler.processEvent(evt);
};

/**
 * Destroy renderer.
 */
AminoGfx.prototype.destroy = function () {
    //clear root copy
    this.root = null;

    this._destroy();

/*
    //call async (outside event handler callbacks)

    setImmediate(() => {
        this._destroy();
    });
*/
};

/**
 * Set position.
 */
AminoGfx.prototype.setPosition = setPosition;

function setPosition(x, y, z) {
    this.x(x).y(y);

    if (z !== undefined) {
        this.z(z);
    }
}

/**
 * Set size.
 */
AminoGfx.prototype.setSize = setSize;

function setSize(w, h) {
    //debug
    //console.log('setSize()');

    this.w(w).h(h);
}

/**
 * Get runtime system info.
 */
AminoGfx.prototype.getStats = function () {
    const stats = this._getStats();
    const mem = process.memoryUsage();

    stats.heapUsed = mem.heapUsed;
    stats.heapTotal = mem.heapTotal;

    return stats;
};

/**
 * Find node with id.
 */
AminoGfx.prototype.find = function (id) {
    function findNodeById(id, node) {
        if (node.id && node.id === id) {
            return node;
        }

        if (node.isGroup) {
            const count = node.getChildCount();

            for (let i = 0; i < count; i++) {
                const ret = findNodeById(id, node.getChild(i));

                if (ret != null) {
                    return ret;
                }
            }
        }

        return null;
    }

    return findNodeById(id, this.getRoot());
};

/**
 * Find a node at a certain position with an optional filter callback.
 */
AminoGfx.prototype.findNodesAtXY = function (pt, filter) {
    //debug
    //console.log('findNodesAtXY()');

    return findNodesAtXY(this.root, pt, filter, '');
};

function findNodesAtXY(root, pt, filter, tab) {
    //verify
    if (!root || !root.visible()) {
        return [];
    }

    //debug
    //console.log(tab + '   xy', pt.x, pt.y, root.id());

    //convert to root coordinates
    const tpt = pt.minus(root.x(), root.y()).divide(root.sx(), root.sy());

    //handle children first, then the parent/root
    let res = [];

    if (filter) {
        //debug
        //console.log('-> using filter on root');

        if (!filter(root)) {
            //debug
            //console.log('-> root skipped');

            return res;
        }
    }

    //check children
    const childCount = root.children?.length;

    if (childCount) {
        //debug
        //console.log('-> checking ' + childCount + ' children');

        for (let i = childCount - 1; i >= 0; i--) {
            const node = root.children[i];
            const found = findNodesAtXY(node, tpt, filter, tab + '  ');

            res = res.concat(found);
        }
    }

    //debug
    //console.log('-> root ' + root.x() + ' ' + root.y() + ' ' + root.w() + ' ' + root.h());
    //console.log('-> point ' + tpt.x + ' ' + tpt.y);

    //check root
    if (root.contains?.(tpt)) {
        //debug
        //console.log('-> added root');

        res.push(root);
    }

    return res;
}

/**
 * Find a node at a certain position.
 */
AminoGfx.prototype.findNodeAtXY = function (x, y) {
    return findNodeAtXY(this.root, x, y, '');
};

function findNodeAtXY(root, x, y, tab) {
    if (!root) {
        return null;
    }

    if (!root.visible()) {
        return null;
    }

    let tx = x - root.x();
    let ty = y - root.y();

    tx /= root.sx();
    ty /= root.sy();

    //console.log(tab + "   xy="+tx+","+ty);

    if (root.cliprect && root.clipRect()) {
        if (tx < 0) {
            return false;
        }

        if (tx > root.w()) {
            return false;
        }

        if (ty < 0) {
            return false;
        }

        if (ty > root.h()) {
            return false;
        }
    }

    if (root.children) {
        //console.log(tab+"children = ",root.children.length);

        for (let i = root.children.length - 1; i >= 0; i--) {
            const node = root.children[i];
            const found = this.findNodeAtXY(node, tx, ty, tab+ '  ');

            if (found) {
                return found;
            }
        }
    }

    //console.log(tab+"contains " + tx+' '+ty);

    if (root.contains && root.contains(tx, ty)) {
        //console.log(tab,"inside!",root.getId());

        return root;
    }

    return null;
}

/**
 * Convert screen coordinate to local node coordinate.
 *
 * Note: only supports translations & scaling (rotation & 3D are not support)
 */
AminoGfx.prototype.globalToLocal = function (pt, node) {
    return convertGlobalToLocal(pt, node);
};

function convertGlobalToLocal(pt, node) {
    //check parent
    if (node.parent) {
        pt = convertGlobalToLocal(pt, node.parent);
    }

    return input.makePoint(
        (pt.x - node.x()) / node.sx(),
        (pt.y - node.y()) / node.sy()
    );
}

/*
function calcGlobalToLocalTransform(node) {
    if (node.parent) {
        const trans = calcGlobalToLocalTransform(node.parent);

        if (node.getScalex() != 1) {
            trans.x /= node.sx();
            trans.y /= node.sy();
        }

        trans.x -= node.x();
        trans.y -= node.y();

        return trans;
    }

    return {
        x: -node.x(),
        y: -node.y()
    };
}
*/

AminoGfx.prototype.localToGlobal = function (pt, node) {
    pt = {
        x: pt.x + node.x() * node.sx(),
        y: pt.y + node.y() * node.sx()
    };

    if (node.parent) {
        return this.localToGlobal(pt, node.parent);
    } else {
        return pt;
    }
};

AminoGfx.prototype.on = function (name, target, listener) {
    this.inputHandler.on(name, target, listener);
};

exports.AminoGfx = AminoGfx;

//
// AminoGfx.Group
//

const Group = AminoGfx.Group;

/**
 * Initializer.
 */
Group.prototype.init = function () {
    if (DEBUG) {
        console.log('Group.init()');
    }

    //bindings
    makeProps(this, {
        id: '',

        //visibility
        visible: true,
        opacity: 1,

        //position
        x: 0,
        y: 0,
        z: 0,

        //size
        w: 100,
        h: 100,

        //origin
        originX: 0,
        originY: 0,

        //scaling
        sx: 1,
        sy: 1,

        //rotation
        rx: 0,
        ry: 0,
        rz: 0,

        //clipping
        clipRect: false,

        //3D rendering (depth test)
        depth: false
    });

    this.isGroup = true;
    this.children = [];
};

/**
 * Check if point is inside of rect.
 */
Group.prototype.contains = contains;

/**
 * Set position.
 */
Group.prototype.setPosition = setPosition;

/**
 * Set size.
 */
Group.prototype.setSize = setSize;

/**
 * Scale.
 */
Group.prototype.scale = scaleFunc;

function scaleFunc(sx, sy) {
    this.sx(sx).sy(sy);
}

/**
 * Rotate.
 */
Group.prototype.rotate = rotateFunc;

function rotateFunc(rx, ry, rz) {
    this.rx(rx).ry(ry).rz(rz);
}

/**
 * Add one or more children to this group.
 */
Group.prototype.add = function () {
    const count = arguments.length;

    if (count === 0) {
        throw new Error('missing parameter');
    }

    for (let i = 0; i < count; i++) {
        const node = arguments[i];

        if (!node) {
            throw new Error('can\'t add a null child to a group');
        }

        if (this.children.indexOf(node) !== -1) {
            throw new Error('child was added before');
        }

        if (node === this || node.parent) {
            throw new Error('already added to different group');
        }

        this._add(node);
        this.children.push(node);
        node.parent = this;
    }

    return this;
};

/**
 * Insert a child at a certain position.
 */
Group.prototype.insertAt = function (item, pos) {
    if (!item) {
        throw new Error('can\'t add a null child to a group');
    }

    if (this.children.indexOf(item) !== -1) {
        throw new Error('child was added before');
    }

    if (item === this || item.parent) {
        throw new Error('already added to different group');
    }

    this._insert(item, pos);
    this.children.splice(pos, 0, item);
    item.parent = this;

    return this;
};

/**
 * Insert before a sibling.
 */
Group.prototype.insertBefore = function (item, sibling) {
    const pos = this.children.indexOf(sibling);

    if (pos === -1) {
        //add at end
        this.add(item);

        return false;
    }

    return this.insertAt(item, pos);
};

/**
 * Insert after a sibling.
 */
Group.prototype.insertAfter = function (item, sibling) {
    const pos = this.children.indexOf(sibling);

    if (pos === -1) {
        //add at end
        this.add(item);

        return false;
    }

    return this.insertAt(item, pos + 1);
};

/**
 * Remove one or more children from this group.
 */
Group.prototype.remove = function () {
    const count = arguments.length;

    if (count === 0) {
        //special case: remove from parent
        if (this.parent) {
            this.parent.remove(this);
        }

        return;
    }

    for (let i = 0; i < count; i++) {
        const child = arguments[i];
        const pos = this.children.indexOf(child);

        if (pos >=  0) {
            this._remove(child);
            this.children.splice(pos, 1);
            child.parent = null;
        } else {
            throw new Error('not a child');
        }
    }

    return this;
};

/**
 * Remove all children.
 */
Group.prototype.clear = function () {
    const count = this.children.length;

    for (let i = 0; i < count; i++) {
        const child = this.children[i];

        this._remove(child);
        child.parent = null;
    }

    this.children = [];

    return this;
};

/**
 * Bring child to top.
 */
Group.prototype.raiseToTop = function (node) {
    if (!node) {
        throw new Error('can\'t move a null child');
    }

    this.remove(node);
    this.add(node);

    return this;
};

/**
 * Free OpenGL resources.
 *
 * Attention: do not call if shared textures are used by any child.
 */
Group.prototype.destroy = function () {
    this.children.forEach(node => {
        if (node.destroy) {
            node.destroy();
        }
    });
};

/**
 * Find children.
 */
Group.prototype.find = function (pattern) {
    const results = new FindResults();

    if (pattern.indexOf('#') === 0) {
        //id
        const id = pattern.substring(1);

        results.children = treeSearch(this, false, function (child) {
            return (child.id().toLowerCase() === id);
        });
    } else {
        //look for class name (e.g. AminoRect)
        pattern = 'amino' + pattern.toLowerCase();

        results.children = treeSearch(this, false, function (child) {
            return child.constructor.name.toLowerCase() === pattern;
        });
    }

    return results;
};

function treeSearch (root, considerRoot, filter) {
    let res = [];

    if (root.isGroup) {
        const count = root.children.length;

        for (let i = 0; i < count; i++) {
            res = res.concat(treeSearch(root.children[i], true, filter));
        }
    }

    if (considerRoot && filter(root)) {
        return res.concat([root]);
    }

    return res;
}

function FindResults() {
    this.children = [];

    function makefindprop(obj, name) {
        obj[name] = function (val) {
            this.children.forEach(child => {
                if (child[name]) {
                    child[name](val);
                }
            });

            return this;
        };
    }

    //TODO review
    makefindprop(this, 'visible');
    makefindprop(this, 'fill');
    makefindprop(this, 'filled');
    makefindprop(this, 'x');
    makefindprop(this, 'y');
    makefindprop(this, 'w');
    makefindprop(this, 'h');

    this.length = function () {
        return this.children.length;
    };
}

//
// Rect
//

const Rect = AminoGfx.Rect;

Rect.prototype.init = function () {
    if (DEBUG) {
        console.log('Rect.init()');
    }

    //properties
    makeProps(this, {
        id: '',
        visible: true,

        //position
        x: 0,
        y: 0,
        z: 0,

        //size
        w: 100,
        h: 100,

        //origin
        originX: 0,
        originY: 0,

        //rotation
        rx: 0,
        ry: 0,
        rz: 0,

        //scaling
        sx: 1,
        sy: 1,

        //white
        fill: '#ffffff',
        r: 1,
        g: 1,
        b: 1,
        opacity: 1.0
    });

    //special
    this.fill.watch(watchFill);
};

/**
 * Check if point is inside of rect.
 */
Rect.prototype.contains = contains;

/**
 * Set position.
 */
Rect.prototype.setPosition = setPosition;

/**
 * Set size.
 */
Rect.prototype.setSize = setSize;

/**
 * Scale.
 */
Rect.prototype.scale = scaleFunc;

/**
 * Rotate.
 */
Rect.prototype.rotate = rotateFunc;

/**
 * Check if a given point is inside this node.
 *
 * Note: has to be used in object.
 *
 * @param pt coordinate relative to origin of node
 */
function contains(pt) {
    return pt.x >= 0 && pt.x < this.w() &&
           pt.y >= 0 && pt.y < this.h();
}

//
// ImageView
//

const ImageView = AminoGfx.ImageView;

ImageView.prototype.init = function () {
    makeProps(this, {
        id: '',
        visible: true,

        //positon
        x: 0,
        y: 0,
        z: 0,

        //size
        w: 100,
        h: 100,

        //origin
        originX: 0,
        originY: 0,

        //scaling
        sx: 1,
        sy: 1,

        //rotation
        rx: 0,
        ry: 0,
        rz: 0,

        //texture coordinates
        left:   0,
        right:  1,
        top:    0,
        bottom: 1,

        //image
        src: null,
        image: null,
        opacity: 1.0,

        position: 'center center',
        size: 'resize',
        repeat: 'no-repeat'
    });

    //actually load the image
    this.src.watch(setSrc);

    //when the image is loaded, update the dimensions
    this.image.watch(texture => {
        //set size
        applySize(texture, this.size(), this.position());
    });

    this.w.watch(_w => {
        applySize(this.image(), this.size(), this.position());
    });

    this.h.watch(_h => {
        applySize(this.image(), this.size(), this.position());
    });

    this.position.watch(pos => {
        //new texture position
        applySize(this.image(), this.size(), pos);
    });

    this.size.watch(mode => {
        //new mode
        applySize(this.image(), mode, this.position());
    });

    const self = this;
    let svgResizeNr = 0;

    async function applySize(texture, mode, position) {
        //debug
        //console.log('applySize() ' + mode);

        //resize SVG
        if (texture?.svg) {
            const newW = self.w();
            const newH = self.h();
            const resizeNr = ++svgResizeNr; //prevent run conditions

            if (newW !== texture.imgW || newH !== texture.imgH) {
                let failed = false;

                await loadTextureFromSvgImage(self, texture.img, (err, texture) => {
                    if (err) {
                        failed = true;
                        return;
                    }

                    if (resizeNr === svgResizeNr) {
                        self.image(texture);
                    }
                });

                if (!failed) {
                    //new image was set
                    return;
                }
            }
        }

        switch (mode) {
            case 'resize':
                if (texture) {
                    self.w(texture.w);
                    self.h(texture.h);
                }
                break;

            case 'stretch':
                //keep size
                break;

            case 'cover':
            case 'contain':
                //cover
                if (texture) {
                    const w = self.w();
                    const h = self.h();
                    let imgW = texture.w;
                    let imgH = texture.h;

                    //fit width
                    imgH *= w / imgW;
                    imgW = w;

                    if (mode === 'cover') {
                        if (imgH < h) {
                            //stretch height
                            imgW *= h / imgH;
                            imgH = h;
                        }
                    } else {
                        if (imgH > h) {
                            const fac = h / imgH;

                            imgW *= fac;
                            imgH *= fac;
                        }
                    }

                    //debug
                    //console.log('fit ' + imgW + 'x' + imgH + ' to ' + w + 'x' + h);

                    //position
                    const pos = position.split(' ');
                    let posHorz = 'center';
                    let posVert = 'center';

                    if (pos.length > 0) {
                        const value = pos[0];

                        if (value === 'left' || value === 'right') {
                            posHorz = value;
                        } else if (value === 'top' || value === 'bottom') {
                            posVert = value;
                        }
                    }

                    if (pos.length > 1) {
                        const value = pos[1];

                        if (value === 'top' || value === 'bottom') {
                            posVert = value;
                        }
                    }

                    //center texture

                    // 1) horz
                    if (posHorz === 'center') {
                        const horz = (imgW - w) / 2 / imgW;

                        self.left(horz);
                        self.right(1 - horz);
                    } else if (posHorz === 'left') {
                        const horz = (imgW - w) / imgW;

                        self.left(0);
                        self.right(1 - horz);
                    } else if (posHorz === 'right') {
                        const horz = (imgW - w) / imgW;

                        self.left(horz);
                        self.right(1);
                    }

                    // 2) vert
                    if (posVert === 'center') {
                        const vert = (imgH - h) / 2 / imgH;

                        self.top(vert);
                        self.bottom(1 - vert);
                    } else if (posVert === 'top') {
                        const vert = (imgH - h) / imgH;

                        self.top(0);
                        self.bottom(1 - vert);
                    } else if (posVert === 'bottom') {
                        const vert = (imgH - h) / imgH;

                        self.top(vert);
                        self.bottom(1);
                    }
                }
                break;
        }
    }
};

/**
 * Set texture.
 */
function setImage(img, obj) {
    //debug
    //console.log('setImage()');

    if (obj.image) {
        obj.image(img);
    } else {
        obj.texture(img);
    }
}

/**
 * Load and set texture.
 */
function loadTexture(obj, img) {
    //check SVG
    if (img.svg) {
        loadTextureFromSvgImage(obj, img, (err, texture) => {
            if (err) {
                if (DEBUG || DEBUG_ERRORS) {
                    console.log('could not load SVG image texture: ' + err.message);
                }

                return;
            }

            //use texture
            setImage(texture, obj);
        });
        return;
    }

    //native image
    const texture = obj.amino.createTexture();

    texture.loadTextureFromImage(img, (err, texture) => {
        if (err) {
            if (DEBUG || DEBUG_ERRORS) {
                console.log('could not load image texture: ' + err.message);
            }

            return;
        }

        //debug
        //console.log('Texture ready.');

        //use texture
        setImage(texture, obj);
    });
}

/**
 * Load and set video texture.
 */
function loadVideoTexture(obj, video) {
    const amino = obj.amino;
    const texture = amino.createTexture();

    texture.loadTextureFromVideo(video, (err, texture) => {
        if (err) {
            if (DEBUG || DEBUG_ERRORS) {
                console.log('could not load video texture: ' + err.message);
            }

            return;
        }

        //use texture
        setImage(texture, obj);
    });
}

/**
 * Src handler.
 *
 * Supports: local files, images, image buffers & textures
 */
function setSrc(src, prop, obj) {
    if (!src) {
        setImage(null, obj);
        return;
    }

    //check image (JPEG, PNG)
    if (src instanceof AminoImage) {
        //load texture
        loadTexture(obj, src);
        return;
    }

    //check video
    if (src instanceof AminoVideo) {
        //load video texture
        loadVideoTexture(obj, src);
        return;
    }

    //load image from source
    const img = new AminoImage();

    obj.tmpImage = img;

    img.onload = err => {
        obj.tmpImage = null;

        if (err) {
            if (DEBUG || DEBUG_ERRORS) {
                console.log('could not load image: ' + err.message);
            }

            //set texture to null
            setImage(null, obj);
            return;
        }

        //debug
        //console.log('image buffer: w=' + img.w + ' h=' + img.h + ' bpp=' + img.bpp + ' len=' + img.buffer.length);

        //load texture
        loadTexture(obj, img);
    };

    img.src = src;
}

/**
 * Abort image loading (network).
 */
function abortTempImage(obj) {
    if (obj.tmpImage) {
        obj.tmpImage.abort();
        obj.tmpImage = null;
    }
}

/**
 * Check if point inside of image view.
 */
ImageView.prototype.contains = contains;

/**
 * Set position.
 */
ImageView.prototype.setPosition = setPosition;

/**
 * Set size.
 */
ImageView.prototype.setSize = setSize;

/**
 * Scale.
 */
ImageView.prototype.scale = scaleFunc;

/**
 * Rotate.
 */
ImageView.prototype.rotate = rotateFunc;

/**
 * Destroy texture.
 *
 * Note: do not call if the texture is used anywhere else.
 */
ImageView.prototype.destroy = function () {
    const img = this.image();

    if (img) {
        this.image(null);
        abortTempImage(this);
        img.destroy();
        img.listeners = null;
    }
};

//
// PixelView
//

class PixelView extends ImageView {
    /**
     * Constructor.
     */
    constructor(amino) {
        super(amino);
    }
}

AminoGfx.PixelView = PixelView;

PixelView.prototype.init = function () {
    //get Rect properties
    ImageView.prototype.init.call(this);

    //bindings
    makeProps(this, {
        pw: 100,
        ph: 100,
        bpp: 4 //RGBA
    });
};

PixelView.prototype.initDone = function () {
    this.pw.watch(rebuildBuffer);
    this.ph.watch(rebuildBuffer);

    const self = this;

    function rebuildBuffer() {
        const w = self.pw();
        const h = self.ph();
        const len = w * h * 4; //RGBA

        if (!self.buf || self.buf.length != len) {
            self.buf = Buffer.alloc(len);
        }

        const c1 = [ 0, 0, 0 ];
        const c2 = [ 255, 255, 255 ];
        const buf = self.buf;

        for (let x = 0; x < w; x++) {
            for (let y = 0; y < h; y++) {
                const i = (x + y * w) * 4;
                let c;

                if (x % 3 === 0) {
                    c = c1;
                } else {
                    c = c2;
                }

                buf[i + 0] = c[0];
                buf[i + 1] = c[1];
                buf[i + 2] = c[2];
                buf[i + 3] = 255;
            }
        }

        self.updateTexture();
    }

    //texture
    this.texture = this.amino.createTexture();
    this.image(this.texture);

    rebuildBuffer();
};

PixelView.prototype.updateTexture = function () {
    this.texture.loadTextureFromBuffer({
        buffer: this.buf,
        w: this.pw(),
        h: this.ph(),
        bpp: this.bpp()
    }, err => {
        if (err) {
            if (DEBUG_ERRORS) {
                console.log('Could not create texture!');
            }

            return;
        }
    });
};

PixelView.prototype.setPixel = function (x, y, r, g, b, a) {
    const w = this.pw();
    const i = (x + y * w) * 4;

    const buf = this.buf;

    buf[i + 0] = r;
    buf[i + 1] = g;
    buf[i + 2] = b;
    buf[i + 3] = a;
};

PixelView.prototype.setPixeli32 = function (x, y, int) {
    const w = this.pw();
    const i = (x + y * w) * 4;

    this.buf.writeUInt32BE(int, i);
};

//
// Polygon
//

const Polygon = AminoGfx.Polygon;

Polygon.prototype.init = function () {
    //bindings
    makeProps(this, {
        id: '',
        visible: true,

        //position
        x: 0,
        y: 0,
        z: 0,

        //scaling
        sx: 1,
        sy: 1,

        //rotation
        rx: 0,
        ry: 0,
        rz: 0,

        //fill
        fill: '#ff0000',
        fillR: 1,
        fillG: 0,
        fillB: 0,
        opacity: 1.,

        //properties
        filled: true,

        dimension: 2, //2D
        geometry: null
    });

    this.fill.watch(setFill);
};

/**
 * Fill value has changed.
 */
function setFill(val, prop, obj) {
    const color = parseRGBString(val);

    obj.fillR(color.r);
    obj.fillG(color.g);
    obj.fillB(color.b);
}

/**
 * Check if point inside of polygon.
 */
Polygon.prototype.contains = function () {
    //TODO check polygon coords
    return false;
};

/**
 * Set position.
 */
Polygon.prototype.setPosition = setPosition;

/**
 * Set size.
 */
Polygon.prototype.setSize = setSize;

/**
 * Scale.
 */
Polygon.prototype.scale = scaleFunc;

/**
 * Rotate.
 */
Polygon.prototype.rotate = rotateFunc;

//
// Model
//

const Model = AminoGfx.Model;

Model.prototype.init = function () {
    //bindings
    makeProps(this, {
        id: '',
        visible: true,

        //position
        x: 0,
        y: 0,
        z: 0,

        //size
        w: 0,
        h: 0,

        //origin
        originX: 0,
        originY: 0,

        //scaling
        sx: 1,
        sy: 1,

        //rotation
        rx: 0,
        ry: 0,
        rz: 0,

        //fill (color mode)
        fill: '#ff0000',
        fillR: 1,
        fillG: 0,
        fillB: 0,
        opacity: 1.,

        //properties
        vertices: null,
        indices: null,
        normals: null, //enables lighting
        uvs: null, //enables texture (color used otherwise)

        src: null,
        texture: null
    });

    this.fill.watch(setFill);
    this.src.watch(setSrc);
};

/**
 * Check if point inside of model.
 */
Model.prototype.contains = function () {
    return false;
};

/**
 * Set position.
 */
Model.prototype.setPosition = setPosition;

/**
 * Set size.
 */
Model.prototype.setSize = setSize;

/**
 * Scale.
 */
Model.prototype.scale = scaleFunc;

/**
 * Rotate.
 */
Model.prototype.rotate = rotateFunc;

/**
 * Destroy texture.
 *
 * Note: do not call if the texture is used anywhere else.
 */
Model.prototype.destroy = function () {
    const texture = this.texture();

    if (texture) {
        abortTempImage(this);
        texture.destroy();
        texture.listeners = null;
    }
};

//
// Circle
//

class Circle extends Polygon {
    /**
     * Constructor.
     */
    constructor(amino) {
        super(amino);
    }
}

AminoGfx.Circle = Circle;

Circle.prototype.init = function () {
    //get Polygon properties
    Polygon.prototype.init.call(this);

    //bindings
    makeProps(this, {
        radius: 0,
        steps: 30
    });

    this.dimension(2);

    //monitor radius updates
    this.radius.watch(r => {
        const steps = this.steps();
        const points = new Float32Array(steps * 2);
        let pos = 0;

        for (let i = 0; i < steps; i++) {
            const theta = Math.PI * 2 / steps * i;

            points[pos++] = Math.sin(theta) * r;
            points[pos++] = Math.cos(theta) * r;
        }

        this.geometry(points);
    });
};

Circle.prototype.initDone = function () {
    this.radius(50);
};

/**
 * Special case for circle.
 */
Circle.prototype.contains = function (pt) {
    const radius = this.radius();
    const dist = Math.sqrt(pt.x * pt.x + pt.y * pt.y);

    return dist < radius;
};

//
// AminoImage
//

const AminoImage = native.AminoImage;

/**
 * src property.
 */
Object.defineProperty(AminoImage.prototype, 'src', {
    set: function (src) {
        this.abort();

        if (!src) {
            //special case
            return;
        }

        //reset SVG
        this.svg = null;

        //check file
        if (typeof src === 'string') {
            //check URLs
            if (src.indexOf('http://') === 0 || src.indexOf('https://') === 0) {
                this.request = request({
                    method: 'GET',
                    uri: src,
                    encoding: null,
                    headers: {
                        'User-Agent': 'AminoGfx/' + packageInfo.version
                    }
                }, (err, response, buffer) => {
                    this.request = null;

                    if (err || (response && response.statusCode !== 200)) {
                        if (this.onload) {
                            this.onload(err || new Error(response.statusCode));
                        }

                        return;
                    }

                    //debug
                    //console.log('image: buffer=' + Buffer.isBuffer(buffer) + ' len=' + buffer.length);

                    //check content type
                    const type = response.headers['content-type'];

                    //SVG handler
                    if (type === 'image/svg+xml') {
                        loadSvgImage(this, buffer, this.onload);
                        return;
                    }

                    //native call
                    this.loadImage(buffer, this.onload, this.maxWH);
                });

                return;
            }

            //read file async
            fs.readFile(src, (err, data) => {
                //check error
                if (err) {
                    if (this.onload) {
                        this.onload(err);
                    }

                    return;
                }

                //check SVG
                if (src.endsWith('.svg')) {
                    loadSvgImage(this, data, this.onload);
                    return;
                }

                //get image
                this.loadImage(data, (err, img) => {
                    //call onload
                    if (this.onload) {
                        this.onload(err, img);
                    }
                }, this.maxWH);
            });

            return;
        }

        //convert buffer
        if (!Buffer.isBuffer(src)) {
            if (this.onload) {
                this.onload(new Error('buffer expected!'));
            }

            return;
        }

        //native call
        this.loadImage(src, this.onload, this.maxWH);
    }
});

/**
 * Load an SVG image.
 *
 * @param {*} buffer
 * @param {*} onload
 */
async function loadSvgImage(img, buffer, onload) {
    if (DEBUG_SVG) {
        console.log('-> loading SVG image');
    }

    try {
        //load SVG
        const svgImg = sharp(buffer);
        const meta = await svgImg.metadata();

        if (meta.format !== 'svg') {
            throw new Error('unknown format');
        }

        if (DEBUG_SVG) {
            console.dir(meta);
        }

        //save for texture usage
        img.svg = svgImg;
    } catch (e) {
        //failed
        if (onload) {
            onload(e);
        }

        return;
    }

    //done
    if (onload) {
        onload(null, img);
    }
}

/**
 * Abort loading (from network).
 */
AminoImage.prototype.abort = function () {
    if (this.request) {
        this.request.abort();
        this.request = null;
    }
};

exports.AminoImage = AminoImage;

//
// AminoVideo
//

const AminoVideo = native.AminoVideo;

exports.AminoVideo = AminoVideo;

//
// AminoFonts
//

const AminoFonts = native.AminoFonts;

AminoFonts.prototype.init = function () {
    this.fonts = {};
    this.cache = {};

    //default fonts
    this.registerFont({
        //Source Sans Pro (https://fonts.google.com/specimen/Source+Sans+Pro)
        name: 'source',
        weights: {
            200: {
                normal: 'SourceSansPro-ExtraLight.ttf',
                italic: 'SourceSansPro-ExtraLightItalic.ttf'
            },
            300: {
                normal: 'SourceSansPro-Light.ttf',
                italic: 'SourceSansPro-LightItalic.ttf'
            },
            400: {
                normal: 'SourceSansPro-Regular.ttf',
                italic: 'SourceSansPro-Italic.ttf'
            },
            600: {
                normal: 'SourceSansPro-Semibold.ttf',
                italic: 'SourceSansPro-SemiboldItalic.ttf'
            },
            700: {
                normal: 'SourceSansPro-Bold.ttf',
                italic: 'SourceSansPro-BoldItalic.ttf'
            },
            900: {
                normal: 'SourceSansPro-Black.ttf',
                italic: 'SourceSansPro-BlackItalic.ttf'
            }
        }
    });

    this.registerFont({
        //Noto UI (https://fonts.google.com/specimen/Source+Sans+Pro)
        name: 'noto-ui',
        weights: {
            400: {
                normal: 'NotoSansUI-Regular.ttf',
                italic: 'NotoSansUI-Italic.ttf'
            },
            700: {
                normal: 'NotoSansUI-Bold.ttf',
                italic: 'NotoSansUI-BoldItalic'
            }
        }
    });

    this.registerFont({
        //Font-Awesome (https://github.com/FortAwesome/Font-Awesome/blob/master/fonts/fontawesome-webfont.ttf)
        name: 'awesome',
        weights: {
            400: {
                normal: 'fontawesome-webfont.ttf'
            }
        }
    });

    //default
    this.defaultFont = this.fonts.source;
};

/**
 * Register a font.
 */
AminoFonts.prototype.registerFont = function (font) {
    //check existing font (immutable)
    if (this.fonts[font.name]) {
        return this;
    }

    //add new font
    this.fonts[font.name] = font;

    //collect weights
    const weightList = [];

    for (let weight in font.weights) {
        weightList.push(weight);
    }

    weightList.sort();
    font.weightList = weightList;

    return this;
};

/**
 * Get a font.
 */
AminoFonts.prototype.getFont = function (descr, callback) {
    if (!descr) {
        descr = {};
    }

    const name = descr.name || this.defaultFont.name;
    const size = Math.round(descr.size || 20);
    let weight = descr.weight || 400;
    let style = descr.style || 'normal';

    //console.log('getFont() ' + name + ' ' + size + ' ' + weight + ' ' + style);

    //get font descriptor
    const font = this.fonts[name];

    if (!font) {
        callback(new Error('font ' + name + ' not found'));
        return this;
    }

    if (!size) {
        callback(new Error('invalid font size'));
        return this;
    }

    //find weight
    let weightDesc = font.weights[weight];

    if (!weightDesc) {
        //find closest
        let closest = null;
        let diff = 0;

        for (let item in font.weights) {
            const diff2 = Math.abs(weight - item);

            if (!closest || diff2 < diff) {
                closest = item;
                diff = diff2;
            }
        }

        if (!closest) {
            callback(new Error('no font weights found for ' + name));
            return this;
        }

        weightDesc = font.weights[closest];
        weight = closest;
    }

    //find style
    let styleDesc = weightDesc[style];

    if (!styleDesc) {
        //fallback to normal
        styleDesc = weightDesc.normal;

        if (!styleDesc) {
            callback(new Error('no normal style found: ' + name + ' weight=' + weight + ' style=' + style));
            return this;
        }

        style = 'normal';
    }

    //check cache
    const key = name + '/' + weight + '/' + style;
    const cached = this.cache[key];

    if (cached) {
        if (cached instanceof Promise) {
            cached.then(font => {
                font.getSize(size, callback);
            }, err => {
                callback(err);
            });
        } else {
            cached.getSize(size, callback);
        }

        return this;
    }

    //path
    let dir = font.path;

    if (!dir) {
        //internal default path
        dir = path.join(__dirname, 'resources/');
    }

    //load file
    const file = path.join(dir, styleDesc);

    const promise = new Promise((resolve, reject) => {
        fs.readFile(file, (err, data) => {
            if (err) {
                reject(err);
                return;
            }

            //throws exception on error
            const font = new AminoFonts.Font(this, {
                data: data,
                file: file,

                name: name,
                weight: weight,
                style: style
            });

            resolve(font);
        });
    });

    this.cache[key] = promise;

    promise.then(font => {
        this.cache[key] = font;

        font.getSize(size, callback);
    }, err => {
        callback(err);
    });

    return this;
};

const fonts = new AminoFonts();

exports.fonts = fonts;

//
// AminoFonts.Font
//

const AminoFont = AminoFonts.Font;

AminoFont.prototype.init = function () {
    this.fontSizes = {};
};

/**
 * Load font size.
 */
AminoFont.prototype.getSize = function (size, callback) {
    //check cache
    let fontSize = this.fontSizes[size];

    if (!fontSize) {
        fontSize = new AminoFonts.FontSize(this, size);
        this.fontSizes[size] = fontSize;
    }

    callback(null, fontSize);
};

//
// AminoFonts.FontSize
//

const AminoFontSize = AminoFonts.FontSize;

/**
 * Calculate text width.
 */
AminoFontSize.prototype.calcTextWidth = function (text, callback) {
    callback(null, this._calcTextWidth(text));
};

//
// AminoGfxTexture
//

const Texture = AminoGfx.Texture;

/**
 * Load texture.
 */
Texture.prototype.loadTexture = function (src, callback) {
    if (!src) {
        this.loadTextureFromBuffer(null, callback);
        return;
    }

    if (src instanceof AminoImage) {
        //check SVG
        if (src.svg) {
            loadTextureFromSvgImage(this, src, callback);
            return;
        }

        //image (JPEG, PNG)
        this.loadTextureFromImage(src, callback);
    } else if (src instanceof AminoVideo) {
        //video (file)
        this.loadTextureFromVideo(src, callback);
    } else if (Buffer.isBuffer(src)) {
        //pixel buffer
        this.loadTextureFromBuffer(src, callback);
    } else if (src instanceof AminoFontSize) {
        //font texture
        this.loadTextureFromFont(src, callback);
    } else {
        throw new Error('unknown source');
    }
};

/**
 * Create texture from SVG image.
 *
 * @param {*} obj
 * @param {*} img
 * @param {*} callback
 */
async function loadTextureFromSvgImage(obj, img, callback) {
    if (DEBUG_SVG) {
        console.log('loadTextureFromSvgImage()');
    }

    try {
        //resize SVG image
        if (obj instanceof Texture) {
            //need size
            throw new Error('need size for SVG');
        }

        const svgImage = img.svg;
        const imgW = obj.w();
        const imgH = obj.h();
        const resized = await svgImage.resize(imgW, imgH, {
            fit: 'contain',
            position: 'centre',
            background: {
                r: 0,
                g: 0,
                b: 0,
                alpha: 0
            }
        });

        //get data
        const { data: buffer, info } = await resized.raw().toBuffer({ resolveWithObject: true });

        if (DEBUG_SVG) {
            console.log('-> using resized SVG texture ' + info.width + 'x' + info.height + ' (' + imgW + 'x' + imgH + ')');
            //console.dir(info);
            //console.dir(img);
            //console.dir(buffer);
        }

        //create texture
        const texture = obj.amino.createTexture();

        texture.loadTextureFromBuffer({
            buffer,
            w: info.width,
            h: info.height,
            bpp: info.channels
        }, err => {
            if (err) {
                return callback(err);
            }

            //store img reference
            texture.svg = svgImage;
            texture.img = img;
            texture.imgW = imgW;
            texture.imgH = imgH;

            callback(null, texture);
        });
    } catch (e) {
        callback(e);
    }
}

/**
 * Add an event listener.
 */
Texture.prototype.addEventListener = function (event, callback) {
    if (arguments.length === 1) {
        callback = event;
        event = '_all';
    }

    if (!this.listeners) {
        this.listeners = [];
    }

    let items = this.listeners[event];

    if (!items) {
        items = [ callback ];
        this.listeners[event] = items;
    } else {
        items.push(callback);
    }

    return this;
};

/**
 * Remove a event listener.
 */
Texture.prototype.removeEventListener = function (event, callback) {
    if (!this.listeners) {
        return this;
    }

    if (arguments.length === 1) {
        callback = event;
        event = '_all';
    }

    const items = this.listeners[event];

    if (items) {
        const idx = items.indexOf(callback);

        if (idx !== -1) {
            this.listeners.splice(idx, 1);
        }
    }

    return this;
};

/**
 * Fire an event.
 */
Texture.prototype.fireEvent = function (event) {
    if (!this.listeners) {
        return;
    }

    //event handlers
    let items = this.listeners[event];

    if (items) {
        const count = items.length;

        for (let i = 0; i < count; i++) {
            items[i](event);
        }
    }

    //global handlers
    items = this.listeners['_all'];

    if (items) {
        const count = items.length;

        for (let i = 0; i < count; i++) {
            items[i](event);
        }
    }
};

//
// AminoGfx.Text
//

const Text = AminoGfx.Text;

Text.prototype.init = function () {
    if (DEBUG) {
        console.log('Text.init()');
    }

    //properties
    makeProps(this, {
        id: '',
        visible: true,

        //position
        x: 0,
        y: 0,
        z: 0,

        //size
        w: 0,
        h: 0,

        //origin
        originX: 0,
        originY: 0,

        //scaling
        sx: 1,
        sy: 1,

        //rotation
        rx: 0,
        ry: 0,
        rz: 0,

        //font
        text:       '',
        fontSize:   20,
        fontName:   'source',
        fontWeight: 400,
        fontStyle:  'normal',
        font:       null,

        //color
        r: 1,
        g: 1,
        b: 1,
        opacity: 1.0,
        fill: '#ffffff',

        //alignment
        align:  'left',
        vAlign: 'baseline',
        wrap:   'none',

        //lines
        maxLines: 0
    });

    this.fill.watch(watchFill);

    //TODO lines
    //TODO textHeight
};

Text.prototype.initDone = function () {
    //update font
    this.updateFont(null, null, this);

    //watchers
    this.fontName.watch(this.updateFont);
    this.fontWeight.watch(this.updateFont);
    this.fontSize.watch(this.updateFont);
};

/**
 * Set position.
 */
Text.prototype.setPosition = setPosition;

/**
 * Set size.
 */
Text.prototype.setSize = setSize;

/**
 * Scale.
 */
Text.prototype.scale = scaleFunc;

/**
 * Rotate.
 */
Text.prototype.rotate = rotateFunc;

let fontId = 0;

/**
 * Load the font.
 */
Text.prototype.updateFont = function (val, prop, obj) {
    //prevent race condition (earlier font is loaded later)
    const id = fontId++;

    obj.latestFontId = id;

    //get font
    fonts.getFont({
        name: obj.fontName(),
        size: obj.fontSize(),
        weight: obj.fontWeight(),
        style: obj.fontStyle(),
    }, (err, font) => {
        //handle errors
        if (err) {
            console.log('could not load font: ' + err.message);

            //try default font
            fonts.getFont({
                size: obj.fontSize()
            }, (err, font) => {
                if (err) {
                    if (DEBUG_ERRORS) {
                        console.log('could not load default font!');
                    }

                    return;
                }

                if (font && obj.latestFontId === id) {
                    obj.latestFontId = undefined;

                    obj.font(font);
                }
            });
            return;
        }

        //attach font

        //console.log('got font: ' + JSON.stringify(font));

        if (obj.latestFontId === id) {
            obj.latestFontId = undefined;

            obj.font(font);
        }
    });

    fontId++;
};

//
// Anim
//

const Anim = AminoGfx.Anim;

/**
 * Initialize instance.
 */
Anim.prototype.init = function () {
    this._from = null;
    this._to = null;
    this._pos = null;
    this._duration = 1000;
    this._loop = 1;
    this._delay = 0;
    this._autoreverse = false;
    this._timeFunc = 'cubicInOut';
    this._then = null;

    this.started = false;
};

/**
 * From animation value.
 */
Anim.prototype.from = function (val) {
    this.checkStarted();

    this._from = val;

    return this;
};

/**
 * To animation value.
 */
Anim.prototype.to = function (val) {
    this.checkStarted();

    this._to = val;

    return this;
};

/**
 * Animation start position value.
 */
Anim.prototype.pos = function (val) {
    this.checkStarted();

    this._pos = val;

    return this;
};

/**
 * Animation duration.
 */
Anim.prototype.dur = function (val) {
    this.checkStarted();

    this._duration = val;

    return this;
};

/**
 * Animation delay.
 */
Anim.prototype.delay = function (val) {
    this.checkStarted();

    this._delay = val;

    return this;
};

/**
 * Animation loop count. Use -1 for forever.
 */
Anim.prototype.loop = function (val) {
    this.checkStarted();

    this._loop = val;

    return this;
};

/**
 * End callback.
 */
Anim.prototype.then = function (fun) {
    this.checkStarted();

    this._then = fun;

    return this;
};

/**
 * Auto reverse animation.
 */
Anim.prototype.autoreverse = function (val) {
    this.checkStarted();

    this._autoreverse = val;

    return this;
};

//Time function values.
const timeFuncs = [ 'linear', 'cubicIn', 'cubicOut', 'cubicInOut' ];

/**
 * Time function.
 */
Anim.prototype.timeFunc = function (value) {
    this.checkStarted();

    if (timeFuncs.indexOf(value) === -1) {
        throw new Error('unknown time function: ' + value);
    }

    this._timeFunc = value;

    return this;
};

/**
 * Internal: check started state.
 */
Anim.prototype.checkStarted = function () {
    if (this.started) {
        throw new Error('immutable after start() was called');
    }
};

/*
 * Start the animation.
 */
Anim.prototype.start = function (refTime) {
    if (this.started) {
        throw new Error('animation already started');
    }

    if (DEBUG) {
        console.log('starting anim');
    }

    this.started = true;

    setTimeout (() => {
        if (DEBUG) {
            console.log('after delay. making it.');
        }

        //validate
        if (this._from === null) {
            throw new Error('missing from value');
        }

        if (this._to === null) {
            throw new Error('missing to value');
        }

        //native start
        this._start({
            from: this._from,
            to: this._to,
            pos: this._pos,
            duration: this._duration,
            refTime: refTime,
            count: this._loop,
            autoreverse: this._autoreverse,
            timeFunc: this._timeFunc,
            then: this._then
        });
    }, this._delay);

    return this;
};

/**
 * Create properties.
 */
function makeProps(obj, props) {
    for (let name in props) {
        makeProp(obj, name, props[name]);
    }

    return obj;
}

/**
 * Create property handlers.
 *
 * @param obj object reference.
 * @param name property name.
 * @param val default value.
 */
function makeProp(obj, name, val) {
    /**
     * Property function.
     *
     * Getter and setter.
     */
    const prop = function AminoProperty(v, nativeCall) {
        //filter null and undefined values (should be string)
        if (v != undefined) {
            return prop.set(v, obj, nativeCall);
        }

        return prop.get();
    };

    prop.value = val;
    prop.propName = name;
    prop.readonly = false;
    prop.nativeListener = null;
    prop.listeners = [];

    /**
     * Add watch callback.
     *
     * Callback: (value, property, object)
     */
    prop.watch = function (fun) {
        if (!fun) {
            throw new Error('function undefined for property ' + name + ' on object with value ' + val);
        }

        this.listeners.push(fun);

        return obj;
    };

    /**
     * Unwatch a registered function.
     */
    prop.unwatch = function (fun) {
        const n = this.listeners.indexOf(fun);

        if (n === -1) {
            throw new Error('function was not registered');
        }

        this.listeners.splice(n, 1);

        return obj;
    };

    /**
     * Remove all listeners.
     */
    prop.unwatchAll = function () {
        this.listeners = [];

        return obj;
    };

    /**
     * Getter function.
     */
    prop.get = function () {
        return this.value;
    };

    /**
     * Setter function.
     */
    prop.set = function (v, obj, nativeCall) {
        //check readonly
        if (this.readonly) {
            //ignore any changes
            return obj;
        }

        //check if modified
        if (v === this.value) {
            //debug
            //console.log('not changed: ' + name);

            return obj;
        }

        //update
        this.value = v;

        //native listener
        if (this.nativeListener && !nativeCall) {
            //prevent recursion in case of updates from native side
            this.nativeListener(this.value, this.propId, obj);
        }

        //fire listeners
        for (let i = 0; i < this.listeners.length; i++) {
            this.listeners[i](this.value, this, obj);
        }

        return obj;
    };

    /**
     * Create animation.
     */
    prop.anim = function (attrs) {
        if (!obj.amino) {
            throw new Error('not an amino object');
        }

        if (!this.propId) {
            throw new Error('property cannot be animated');
        }

        const anim = new AminoGfx.Anim(obj.amino, obj, this.propId);

        if (attrs) {
            for (let key in attrs) {
                anim['_' + key] = attrs[key];
            }
        }

        return anim;
    };

    /**
     * Bind to other property.
     *
     * Optional: callback to modify value.
     */
    prop.bindTo = function (prop, fun) {
        const set = this;

        function watcher(v) {
            if (fun) {
                set(fun(v));
            } else {
                set(v);
            }
        }

        prop.listeners.push(watcher);

        //apply current value
        watcher(prop());

        return obj;
    };

    //Note: no unbind method -> use prop.unwatchAll()

    obj.attr = function (attrs) {
        for (let key in attrs) {
            const prop = this[key];

            if (prop) {
                const value = attrs[key];

                //check watch
                if (typeof value === 'function') {
                    prop.watch(value);
                    return;
                }

                //check bindTo
                if (value.name === 'AminoProperty') {
                    prop.bindTo(value);
                    return;
                }

                //normal assignment
                prop(value);
            } else {
                console.log('unknown attribute: ' + key);
            }
        }

        return obj;
    };

    //attach
    obj[name] = prop;
}

exports.makeProps = makeProps;

//
// AminoWeakReference
//
exports.AminoWeakReference = native.AminoWeakReference;

//input
const input = require('./src/core/aminoinput');

// initialize input handler
input.init();

exports.input = input;