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/*******************************************************************************

    uBlock Origin - a comprehensive, efficient content blocker
    Copyright (C) 2019-present Raymond Hill

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see {http://www.gnu.org/licenses/}.

    Home: https://github.com/gorhill/uBlock

*/

import { registerScriptlet } from './base.js';

/******************************************************************************/

export function proxyApplyFn(
    target = '',
    handler = ''
) {
    let context = globalThis;
    let prop = target;
    for (;;) {
        const pos = prop.indexOf('.');
        if ( pos === -1 ) { break; }
        context = context[prop.slice(0, pos)];
        if ( context instanceof Object === false ) { return; }
        prop = prop.slice(pos+1);
    }
    const fn = context[prop];
    if ( typeof fn !== 'function' ) { return; }
    if ( proxyApplyFn.CtorContext === undefined ) {
        proxyApplyFn.ctorContexts = [];
        proxyApplyFn.CtorContext = class {
            constructor(...args) {
                this.init(...args);
            }
            init(callFn, callArgs) {
                this.callFn = callFn;
                this.callArgs = callArgs;
                return this;
            }
            reflect() {
                const r = Reflect.construct(this.callFn, this.callArgs);
                this.callFn = this.callArgs = this.private = undefined;
                proxyApplyFn.ctorContexts.push(this);
                return r;
            }
            static factory(...args) {
                return proxyApplyFn.ctorContexts.length !== 0
                    ? proxyApplyFn.ctorContexts.pop().init(...args)
                    : new proxyApplyFn.CtorContext(...args);
            }
        };
        proxyApplyFn.applyContexts = [];
        proxyApplyFn.ApplyContext = class {
            constructor(...args) {
                this.init(...args);
            }
            init(callFn, thisArg, callArgs) {
                this.callFn = callFn;
                this.thisArg = thisArg;
                this.callArgs = callArgs;
                return this;
            }
            reflect() {
                const r = Reflect.apply(this.callFn, this.thisArg, this.callArgs);
                this.callFn = this.thisArg = this.callArgs = this.private = undefined;
                proxyApplyFn.applyContexts.push(this);
                return r;
            }
            static factory(...args) {
                return proxyApplyFn.applyContexts.length !== 0
                    ? proxyApplyFn.applyContexts.pop().init(...args)
                    : new proxyApplyFn.ApplyContext(...args);
            }
        };
    }
    const fnStr = fn.toString();
    const toString = (function toString() { return fnStr; }).bind(null);
    const proxyDetails = {
        apply(target, thisArg, args) {
            return handler(proxyApplyFn.ApplyContext.factory(target, thisArg, args));
        },
        get(target, prop) {
            if ( prop === 'toString' ) { return toString; }
            return Reflect.get(target, prop);
        },
    };
    if ( fn.prototype?.constructor === fn ) {
        proxyDetails.construct = function(target, args) {
            return handler(proxyApplyFn.CtorContext.factory(target, args));
        };
    }
    context[prop] = new Proxy(fn, proxyDetails);
}
registerScriptlet(proxyApplyFn, {
    name: 'proxy-apply.fn',
});