// SPDX-License-Identifier: MIT
// Copyright © 2021 fvtt-lib-wrapper Rui Pinheiro


'use strict';

// A shim for the libWrapper library
export let libWrapper = undefined;

export const VERSIONS       = [1,12,2];
export const TGT_SPLIT_RE   = new RegExp("([^.[]+|\\[('([^'\\\\]|\\\\.)+?'|\"([^\"\\\\]|\\\\.)+?\")\\])", 'g');
export const TGT_CLEANUP_RE = new RegExp("(^\\['|'\\]$|^\\[\"|\"\\]$)", 'g');

// Main shim code
Hooks.once('init', () => {
  // Check if the real module is already loaded - if so, use it
  if(globalThis.libWrapper && !(globalThis.libWrapper.is_fallback ?? true)) {
    libWrapper = globalThis.libWrapper;
    return;
  }

  // Fallback implementation
  libWrapper = class {
    static get is_fallback() { return true };

    static get WRAPPER()  { return 'WRAPPER'  };
    static get MIXED()    { return 'MIXED'    };
    static get OVERRIDE() { return 'OVERRIDE' };

    static register(package_id, target, fn, type="MIXED", {chain=undefined, bind=[]}={}) {
      const is_setter = target.endsWith('#set');
      target = !is_setter ? target : target.slice(0, -4);
      const split = target.match(TGT_SPLIT_RE).map((x)=>x.replace(/\\(.)/g, '$1').replace(TGT_CLEANUP_RE,''));
      const root_nm = split.splice(0,1)[0];

      let obj, fn_name;
      if(split.length == 0) {
        obj = globalThis;
        fn_name = root_nm;
      }
      else {
        const _eval = eval;
        fn_name = split.pop();
        obj = split.reduce((x,y)=>x[y], globalThis[root_nm] ?? _eval(root_nm));
      }

      let iObj = obj;
      let descriptor = null;
      while(iObj) {
        descriptor = Object.getOwnPropertyDescriptor(iObj, fn_name);
        if(descriptor) break;
        iObj = Object.getPrototypeOf(iObj);
      }
      if(!descriptor || descriptor?.configurable === false) throw new Error(`libWrapper Shim: '${target}' does not exist, could not be found, or has a non-configurable descriptor.`);

      let original = null;
      const wrapper = (chain ?? (type.toUpperCase?.() != 'OVERRIDE' && type != 3)) ?
                      function(...args) { return fn.call(this, original.bind(this), ...bind, ...args); } :
                      function(...args) { return fn.call(this, ...bind, ...args); }
      ;

      if(!is_setter) {
        if(descriptor.value) {
          original = descriptor.value;
          descriptor.value = wrapper;
        }
        else {
          original = descriptor.get;
          descriptor.get = wrapper;
        }
      }
      else {
        if(!descriptor.set) throw new Error(`libWrapper Shim: '${target}' does not have a setter`);
        original = descriptor.set;
        descriptor.set = wrapper;
      }

      descriptor.configurable = true;
      Object.defineProperty(obj, fn_name, descriptor);
    }
  }

  //************** USER CUSTOMIZABLE:
  // Set up the ready hook that shows the "libWrapper not installed" warning dialog. Remove if undesired.
  {
    //************** USER CUSTOMIZABLE:
    // Package ID & Package Title - by default attempts to auto-detect, but you might want to hardcode your package ID and title here to avoid potential auto-detect issues
    const [PACKAGE_ID, PACKAGE_TITLE] = (()=>{
      const match = (import.meta?.url ?? Error().stack)?.match(/\/(worlds|systems|modules)\/(.+)(?=\/)/i);
      if(match?.length !== 3) return [null,null];
      const dirs = match[2].split('/');
      if(match[1] === 'worlds') return dirs.find(n => n && game.world.id === n) ? [game.world.id, game.world.title] : [null,null];
      if(match[1] === 'systems') return dirs.find(n => n && game.system.id === n) ? [game.system.id, game.system.title ?? game.system.data.title] : [null,null];
      const id = dirs.find(n => n && game.modules.has(n));
      const mdl = game.modules.get(id);
      return [id, mdl?.title ?? mdl?.data?.title];
    })();

    if(!PACKAGE_ID || !PACKAGE_TITLE) {
      console.error("libWrapper Shim: Could not auto-detect package ID and/or title. The libWrapper fallback warning dialog will be disabled.");
      return;
    }

    Hooks.once('ready', () => {
      //************** USER CUSTOMIZABLE:
      // Title and message for the dialog shown when the real libWrapper is not installed.
      const FALLBACK_MESSAGE_TITLE = PACKAGE_TITLE;
      const FALLBACK_MESSAGE = `
				<p><b>'${PACKAGE_TITLE}' depends on the 'libWrapper' module, which is not present.</b></p>
				<p>A fallback implementation will be used, which increases the chance of compatibility issues with other modules.</p>
				<small><p>'libWrapper' is a library which provides package developers with a simple way to modify core Foundry VTT code, while reducing the likelihood of conflict with other packages.</p>
				<p>You can install it from the "Add-on Modules" tab in the <a href="javascript:game.shutDown()">Foundry VTT Setup</a>, from the <a href="https://foundryvtt.com/packages/lib-wrapper">Foundry VTT package repository</a>, or from <a href="https://github.com/ruipin/fvtt-lib-wrapper/">libWrapper's Github page</a>.</p></small>
			`;

      // Settings key used for the "Don't remind me again" setting
      const DONT_REMIND_AGAIN_KEY = "libwrapper-dont-remind-again";

      // Dialog code
      console.warn(`${PACKAGE_TITLE}: libWrapper not present, using fallback implementation.`);
      game.settings.register(PACKAGE_ID, DONT_REMIND_AGAIN_KEY, { name: '', default: false, type: Boolean, scope: 'world', config: false });
      if(game.user.isGM && !game.settings.get(PACKAGE_ID, DONT_REMIND_AGAIN_KEY)) {
        console.group(`${PACKAGE_TITLE} warning: libWrapper not present`)
        console.warn('A fallback implementation will be used, which increases the chance of compatibility issues with other modules. If you find that some functionality if not working correctly, please consider installing the "libWrapper" module.');
        console.info("'libWrapper' is a library which provides package developers with a simple way to modify core Foundry VTT code, while reducing the likelihood of conflict with other packages.");
        console.info('You can install it from the "Add-on Modules" tab in Foundry VTT Setup.');
        console.groupEnd();
      }
    });
  }
});
