Geomancy

//=============================================================================
//  Geomancy.js
//=============================================================================
//  Version: 1.0.1
//  Date: 31 October 2015
//+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
/*:
 * @plugindesc Set terrain and region restrictions on skill use
 * @author Modern Algebra (rmrk.net)
 * @help To set up a skill so that it can only be used in certain terrains, you
 * need to put one of the following codes in its notebox:
 *
 *      <onlyTerrains:x>
 *      <prohibitedTerrains:y>
 *
 * If you use the onlyTerrains code, then the skill can be used only on terrains
 * with ID x. If you use the prohibitedTerrains code, then the skill can only be
 * used if the party is not on the terrain with ID y. In both cases, x and y
 * must be set to integers. You can set as many terrain tags as you want; just
 * separate them with a space or a comma.
 *
 * The region codes work essentially the same way.
 *
 *      <onlyRegions:x>
 *      <prohibitedRegions:x>
 *
 * Examples:
 *
 *      <onlyRegions:1 3 4 76>
 *          The skill can only be used when the party is in regions 1, 3, 4, or 76
 *
 *      <prohibitedRegions:5 10>
 *          The skill can be used in every region except regions 5 and 10
 *
 *      <onlyTerrains:7>
 *          The skill can only be used on tiles marked with terrain tag 7.
 */
//=============================================================================

(function() {

    // Game_BattlerBase - meetsSkillConditions
    //   Test terrain and region too
    var _mag_Game_BattlerBase_meetsSkillConditions =
            Game_BattlerBase.prototype.meetsSkillConditions;
    Game_BattlerBase.prototype.meetsSkillConditions = function(skill) {
        var skillTest = _mag_Game_BattlerBase_meetsSkillConditions.apply(this, arguments);
        if (!skillTest || DataManager.isBattleTest()) { return skillTest; }
        return this.magMeetsSkillTerrainConditions(skill);
    };

    // Game_BattlerBase - Test terrain and region conditions for skills
    Game_BattlerBase.prototype.magMeetsSkillTerrainConditions = function(skill) {
        var terrainTag = $gamePlayer.terrainTag();
        var regionId = $gamePlayer.regionId();
        var rpatt = /\d+/g
        // Can't use if on an expressly prohibited terrain
        var prohibitedTerrains = skill.meta.prohibitedTerrains;
        if (prohibitedTerrains) {
            var match = prohibitedTerrains.match(rpatt);
            if (match && match.map(Number).contains(terrainTag)) { return false; }
        }
        // Can't use if in an expressly prohibited region
        var prohibitedRegions = skill.meta.prohibitedRegions;
        if (prohibitedRegions) {
            var match = prohibitedRegions.match(rpatt);
            if (match && match.map(Number).contains(regionId)) { return false; }
        }
        // Can't use if exclusive terrains defined and not on one
        var onlyTerrains = skill.meta.onlyTerrains;
        if (onlyTerrains) {
            var match = onlyTerrains.match(rpatt);
            if (match && !match.map(Number).contains(terrainTag)) { return false; }
        }
        // Can't use if exclusive regions defined and not in one
        var onlyRegions = skill.meta.onlyRegions;
        if (onlyRegions) {
            var match = onlyRegions.match(rpatt);
            if (match && !match.map(Number).contains(regionId)) { return false; }
        }
        return true; // Can use the skill otherwise
    };

})();