@mezzy/signals/src/signal.js

A luxurious user experience framework, developed by your friends at Mezzanine.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
const ids_1 = require("@mezzy/ids");
const signalBinding_1 = require("./signalBinding");
class Signal {
    constructor(isMemorize = false) {
        this._key = `signal_${ids_1.default.getSessionUniqueInteger()}`;
        this._bindings = [];
        this._prevParam = null;
        this._isMemorize = isMemorize;
        this._isDispatched = false;
        this._isShouldPropagate = true;
        this.isActive = true;
    }
    get key() { return this._key; }
    get listenerCount() { return !!this._bindings ? this._bindings.length : 0; }
    get isMemorize() { return this._isMemorize; }
    ;
    validateListener(listener, fnName) {
        if (typeof listener !== 'function') {
            throw new Error('listener is a required param of {fn}() and should be a Function.'.replace('{fn}', fnName));
        }
    }
    _registerListener(listener, isOnce, listenerContext, priority) {
        let prevIndex = this._indexOfListener(listener, listenerContext);
        let binding;
        if (prevIndex !== -1) {
            binding = this._bindings[prevIndex];
            if (binding.isOnce() !== isOnce) {
                throw new Error('You cannot listen' + (isOnce ? '' : 'Once') + '() then add' + (!isOnce ? '' : 'Once')
                    + '() the same listener without removing the relationship first.');
            }
        }
        else {
            binding = new signalBinding_1.default(this, listener, isOnce, listenerContext, priority);
            this._addBinding(binding);
        }
        if (this.isMemorize && this._isDispatched) {
            binding.execute(this._prevParam);
        }
        return binding;
    }
    _addBinding(binding) {
        let n = this._bindings.length;
        do {
            --n;
        } while (this._bindings[n] && binding.priority <= this._bindings[n].priority);
        this._bindings.splice(n + 1, 0, binding);
    }
    _indexOfListener(listener, context) {
        let indexCurrent = this._bindings.length;
        let bindingCurrent;
        while (indexCurrent--) {
            bindingCurrent = this._bindings[indexCurrent];
            if (bindingCurrent.listener === listener && bindingCurrent.context === context)
                return indexCurrent;
        }
        return -1;
    }
    has(listener, context = null) { return this._indexOfListener(listener, context) !== -1; }
    listen(listener, listenerContext = null, priority = 0) {
        this.validateListener(listener, 'listen');
        return this._registerListener(listener, false, listenerContext, priority);
    }
    listenOnce(listener, listenerContext = null, priority = 0) {
        this.validateListener(listener, 'listenOnce');
        return this._registerListener(listener, true, listenerContext, priority);
    }
    delete(listener, context = null) {
        this.validateListener(listener, 'remove');
        let i = this._indexOfListener(listener, context);
        if (i !== -1) {
            this._bindings[i].destroy();
            this._bindings.splice(i, 1);
        }
        return listener;
    }
    deleteAll() {
        let n = this._bindings.length;
        while (n--) {
            this._bindings[n].destroy();
        }
        this._bindings.length = 0;
    }
    halt() { this._isShouldPropagate = false; }
    dispatch(param) {
        if (!this.isActive)
            return;
        let n = this._bindings.length;
        let bindings;
        if (this.isMemorize) {
            this._prevParam = param;
            this._isDispatched = true;
        }
        if (!n) {
            return;
        }
        bindings = this._bindings.slice(0);
        this._isShouldPropagate = true;
        do {
            n--;
        } while (bindings[n] && this._isShouldPropagate && bindings[n].execute(param) !== false);
    }
    forget() {
        this._prevParam = null;
        this._isDispatched = false;
    }
    dispose() {
        this.deleteAll();
        this._bindings.splice(0);
        delete this._prevParam;
    }
    toString() { return '[Signal isActive:' + this.isActive + ' numListeners:' + this.listenerCount + ']'; }
}
exports.Signal = Signal;
exports.default = Signal;
//# sourceMappingURL=signal.js.map