More Page Conditions (MV)

/*:
 * More Page Conditions by Shaz
 * Ver 1.00 2018.01.23
 * Shaz_MorePageConditions.js
 *
 *
 * @plugindesc Adds more flexible page conditions via comments.
 * @author Shaz
 *
 * @help This plugin has no plugin commands.
 *
 * Add comments to the top of an event page to include them when checking if
 * the current page should be activated.  The comment block should begin with
 * the word cond
 *
 * The following shortened formats are available:
 * \ss([1, 2, 'A']) - converts to $gameSelfSwitches.value([1, 2, 'A'])
 * \s(15)           - converts to $gameSwitches.value(15)
 * \v(8)            - converts to $gameVariables.value(8)
 *
 * Any other valid command can be included, including combinations with
 * && and || and ().
 *
 * Examples:
 * cond \s(15) && \s(16] && \s(17) - page will be active if all 3 switches are
 *      on, and any other page conditions are met
 * cond \v(8) >= 10 && \v(8) <= 15 - page will be active if the variable is
 *      between 10 and 15, inclusive
 *
 * Note - although you can add any script call that will evaluate to true/false
 * as a condition, it may not cause an immediate change of pages.  The map
 * only evaluates page conditions when something has requested a refresh.  By
 * default, this list only includes things shown under the Conditions section
 * of the event page - a change to switches, self switches, variables, party
 * members, and items (which means items, armor or weapons).  If you want to
 * add a condtion based on something else (for example, amount of gold, hp of
 * party leader, etc), you will need to manually add a script call at the time
 * those things can change: $gameMap.requestRefresh()
 * Be careful not to do this too often - definitely not in a parallel process
 * event, as refreshing the page events is a CPU-hungry activity and will
 * cause lag if done too frequently.
 *
 */

var Imported = Imported || {};
Imported.Shaz_MorePageConditions = true;

var Shaz = Shaz || {};
Shaz.MPC = Shaz.MPC || {};
Shaz.MPC.Version = 1.00;

(function() {
    var _Shaz_Game_Event_meetsConditions = Game_Event.prototype.meetsConditions;
    Game_Event.prototype.meetsConditions = function(page) {
        var test1 = _Shaz_Game_Event_meetsConditions.call(this, page);
        var test2 = this.meetsExtraConditions(page);
        return test1 && test2;
    };

    Game_Event.prototype.meetsExtraConditions = function(page) {
        var l = page.list.filter(function(cmd) {
            return cmd.code === 108 || cmd.code === 408;
        });

        var building = false;
        var cond = '';
        l.forEach(function(cmd) {
            if (cmd.parameters[0].match(/^cond (.*)$/i)) {
                cond += ' ' + RegExp.$1;
                building = true;
            } else if (cmd.code === 408 && building) {
                cond += ' ' + RegExp.$1;
            } else {
                building = false;
            }
        }, this);

        if (cond) {
            cond = cond.replace(/\\ss/gi, '$gameSelfSwitches.value');
            cond = cond.replace(/\\s/gi, '$gameSwitches.value');
            cond = cond.replace(/\\v/gi, '$gameVariables.value');
            return eval(cond);
        } else {
            return true;
        }
    };

})();