//-----------------------------------------------------------------------------
// Window_SkillList
//
// The window for selecting a skill on the skill screen.
/**
 * The window for selecting a skill on the skill screen.
 *
 * @class
 * @extends Window_Selectable
 */
function Window_SkillList() {
    this.initialize(...arguments);
}

Window_SkillList.prototype = Object.create(Window_Selectable.prototype);
Window_SkillList.prototype.constructor = Window_SkillList;

Window_SkillList.prototype.initialize = function(rect) {
    Window_Selectable.prototype.initialize.call(this, rect);
    this._actor = null;
    this._stypeId = 0;
    this._data = [];
};

/**
 * Sets the actor object for the window
 *
 * @param {Game_Actor} actor - The Game Actor object
 */
Window_SkillList.prototype.setActor = function(actor) {
    if (this._actor !== actor) {
        this._actor = actor;
        this.refresh();
        this.scrollTo(0, 0);
    }
};

/**
 * Sets the skill type Id for the window
 *
 * @param {number} stypeId - The skill type id
 */
Window_SkillList.prototype.setStypeId = function(stypeId) {
    if (this._stypeId !== stypeId) {
        this._stypeId = stypeId;
        this.refresh();
        this.scrollTo(0, 0);
    }
};

/**
 * Get the max amount of columns in the window
 *
 * @return {number} Max columns for the window
 */
Window_SkillList.prototype.maxCols = function() {
    return 2;
};

/**
 * Get the spacing between columns
 *
 * @return {number} Space between columns
 */
Window_SkillList.prototype.colSpacing = function() {
    return 16;
};

/**
 * Get the max amount of items to display in the window
 *
 * @return {number} Amount of items to display in the window
 */
Window_SkillList.prototype.maxItems = function() {
    return this._data ? this._data.length : 1;
};

/**
 * Get the currently selected item
 *
 * @return {Object} The skill object at the current index
 */
Window_SkillList.prototype.item = function() {
    return this.itemAt(this.index());
};

/**
 * Get the object at the given index
 *
 * @param {number} index - The index of the item
 * @return {Object} The skill object at the current index
 */
Window_SkillList.prototype.itemAt = function(index) {
    return this._data && index >= 0 ? this._data[index] : null;
};

/**
 * Check if the currently selected skill is enabled
 *
 * @return {boolean} True if the skill is enabled
 */
Window_SkillList.prototype.isCurrentItemEnabled = function() {
    return this.isEnabled(this._data[this.index()]);
};

/**
 * Check if the skill should be included
 *
 * @param {Object} item - The skill object
 * @return {boolean} True if the skill is included
 */
Window_SkillList.prototype.includes = function(item) {
    return item && item.stypeId === this._stypeId;
};

/**
 * Check if the skill should be enabled
 *
 * @param {Object} item - The skill object
 * @return {boolean} True if the skill is enabled
 */
Window_SkillList.prototype.isEnabled = function(item) {
    return this._actor && this._actor.canUse(item);
};

/**
 * Makes the list of items to display in the window
 */
Window_SkillList.prototype.makeItemList = function() {
    if (this._actor) {
        this._data = this._actor.skills().filter(item => this.includes(item));
    } else {
        this._data = [];
    }
};

/**
 * Select the last skill, if remembered
 */
Window_SkillList.prototype.selectLast = function() {
    const index = this._data.indexOf(this._actor.lastSkill());
    this.forceSelect(index >= 0 ? index : 0);
};

/**
 * Draws the item at the given index
 *
 * @param {number} index - The index of the item to draw
 */
Window_SkillList.prototype.drawItem = function(index) {
    const skill = this.itemAt(index);
    if (skill) {
        const costWidth = this.costWidth();
        const rect = this.itemLineRect(index);
        this.changePaintOpacity(this.isEnabled(skill));
        this.drawItemName(skill, rect.x, rect.y, rect.width - costWidth);
        this.drawSkillCost(skill, rect.x, rect.y, rect.width);
        this.changePaintOpacity(1);
    }
};

/**
 * Get the width of cost text
 *
 * @return {number} The width of cost text
 */
Window_SkillList.prototype.costWidth = function() {
    return this.textWidth("000");
};

/**
 * Draws the skill's cost
 *
 * @param {Object} skill - The skill object
 * @param {number} x - The x coordinate to draw the cost
 * @param {number} y - The y coordinate to draw the cost
 * @param {number} width - The width available to draw the cost
 */
Window_SkillList.prototype.drawSkillCost = function(skill, x, y, width) {
    if (this._actor.skillTpCost(skill) > 0) {
        this.changeTextColor(ColorManager.tpCostColor());
        this.drawText(this._actor.skillTpCost(skill), x, y, width, "right");
    } else if (this._actor.skillMpCost(skill) > 0) {
        this.changeTextColor(ColorManager.mpCostColor());
        this.drawText(this._actor.skillMpCost(skill), x, y, width, "right");
    }
};

/**
 * Updates helper windows
 */
Window_SkillList.prototype.updateHelp = function() {
    this.setHelpWindowItem(this.item());
};

Window_SkillList.prototype.refresh = function() {
    this.makeItemList();
    Window_Selectable.prototype.refresh.call(this);
};