require ('./useless')

UselessApp = $singleton (Component, {

    $defaults: {
        webpackEntries: {
            entry: {
                'shared': { // duplicate code will be extracted to shared.js
                    'useless.client':   "./node_modules/useless/build/useless.client.js",
                    'useless.devtools': "./node_modules/useless/build/useless.devtools.js",
                    'index':            "./example/index.js",
                }
            }
        },
        config: {
            webpack: {
                hotReload: true
            }
        }
    },

    $depends: [
        require ('./server/supervisor'), // for auto-reload on code change
        require ('./server/webpack'),
        require ('./server/http')
    ],

/*  Members starting with "/" are HTTP request handlers         */

    '/hello-world':       () => "Hello world!",          // text/plain; charset=utf-8
    '/hello-world/json':  () => ({ foo: 42, bar: 777 }), // application/json; charset=utf-8

/*  File serving  */

    '/':             () => $this.file ('./static/index.html'), // $this is a smart alias for `this`, accessible from anywhere in the request execution context
    '/static/:file': () => $this.file ('./static'),            // any file from ./static folder

/*  Query params matching  */

    '/sqr?x={\\d+}':          ({ x    }) => Math.pow (Number (x),         2),  // x²
    '/pow?x={\\d+}&n={\\d+}': ({ x, n }) => Math.pow (Number (x), Number (n)), // x^n
                 
/*  Put your JSONAPI stuff in /api    */

    '/api': { // tree-style definitions are supported
        
        'login':  { post: async () => $this.doLogin (await $this.receiveJSON) },
        'logout': { post:       () => $http.removeCookies (['email', 'password']) },
    },

/*  A complex request handler example, demonstrating some core features.

    All execution is wrapped into so-called "supervised Promise chain",
    so you don't need to pass the request context explicitly, it is always
    available as $http object in any promise callback related to request
    represented by that object.
    
    All thrown errors and all log messages are handled by the engine
    automagically. It builds a process/event hierarchy that reflects the
    actual execution flow, so you don't need to run a debugger to see what's
    going on, it's all in the log. Request is automatically ended when an
    unhandled exception occurs, no need to trigger it explicitly.               */

    async doLogin ({ email, password }) {

        if (await this.findUser ({ email, password })) {

            $http.setCookies ({ email, password })

        } else {

            throw new Error ('Wrong credentials')
        }
    },

    async findUser (criteria) { /* ... */ },

    init () {

        log.ok ('App started')
    }
})

Vec2 = $prototype ({

    /*  Constructor
     */
    constructor: function (x, y) { this.x = x; this.y = y },

    /*  Instance method
     */
    add (other) { return new Vec2 (this.x + other.x, this.y + other.y) }

    /*  Instance property (.length)
     */
    get length () { return Math.sqrt (this.x * this.x + this.y * this.y) }),

    /*  Static property: Vec2.zero
     */
    zero: $static ($property (function () { return new Vec2 (0, 0) })),

    /*  Static method: Vec2.dot (a, b)
     */
    dot: $static (function (a, b) { return a.x * b.x + a.y * b.y }),

    /*  Tag groups for convenience
     */
    $static: {
        unit: $property (function () { return new Vec2 (1, 1) }),
        one:  $alias ('unit') }, // member aliases
})

/*  Inheritance (relies on native JavaScript prototype semantics)
 */
BetterVec2 = $extends (Vec2, { /* ... */ })

var mouseMoved = _.trigger ()

/*  Binding
 */
mouseMoved (function (x, y) { }) // bind
mouseMoved (someCallback)        // bind another
mouseMoved.once (someCallback)   // bind with 'once' semantics (auto-unbinds itself upon calling)

/*  Calling
 */
mouseMove (12, 33)               // call

/*  Unbinding
 */
mouseMove.off (someCallback)     // unbinds specific listener
mouseMove.off ()                 // unbinds everything
_.off (someCallback)             // unbinds callback from everything it's bound to

Compo = $component ({

    didLayout:     $trigger (),
    layoutReady:   $barrier (),             // it's like jQueryish $(document).ready
    value:         $observableProperty (),  // for property change notifications
    
    init: function () {
        doSomeUselessAsyncJob (function () {
           this.layoutReady () }) }, // signals that layout is ready

    doLayout: function () {
        this.didLayout () } })       // simply call to perform multicast

compo = new Compo ()

compo.didLayout (function () {
    /*  Gets called whenether layout has rebuilt */ })

compo.layoutReady (function () {
    /*  Postpones until DOM is ready.
        If already, calls immediately (like $(document).ready) */ })

compo.valueChange (function (value, oldValue) {
    /*  Gets called whenether property has assigned distinct value */ })

compo.value = 10 // simply assign a value to notify listeners
compo.value = 10 // won't trigger, as not changed

_.onAfter   (Player.prototype, 'move', function (x, y) { /* this will execute after move calls */ })
_.onBefore  (Player.prototype, 'move', function (x, y) { /* this will execute before */ })
_.intercept (Player.prototype, 'move', function (x, y, originalMethod) {
    originalMethod.call (this, x, y) })

Button = $component ({
    layout: $bindable (function () { /* ... */ }) })
    
button = new Button ()
button.layout.onceBefore (function () { log ("I'm called before next layout()") })
button.layout ()
button.layout () // won't print anything

    _.lerp  (t, min, max)  // linear interpolation between min and max
    _.clamp (n, min, max)  // clips if out of range
    
    /*  Projects from one range to another (super useful in widgets implementation)
     */
    _.rescale (t, [fromMin, fromMax], [toMin, toMax], { clamp: true })

   var offsetVec = this.anchor.sub (this.center).normal.perp.scale (
                       Bezier.cubic1D (
                           Vec2.dot (direction.normal, upVector), 0, 1.22, 0, 1.9))

   var where = this.bodyBBox.nearestPointTo (this.anchor, this.borderRadius)

   domElement.css (BBox.fromPoints (pts).grow (20).offset (position.inverse).css)