/**
 * A specialized form used to select from a checklist of attributes, traits, or properties
 * @extends {DocumentSheet}
 */
export default class TraitSelector extends DocumentSheet {
    /** @inheritdoc */
    static get defaultOptions() {
        return foundry.utils.mergeObject(super.defaultOptions, {
            id: "trait-selector",
            classes: ["sw5e", "trait-selector", "subconfig"],
            title: "Actor Trait Selection",
            template: "systems/sw5e/templates/apps/trait-selector.html",
            width: 320,
            height: "auto",
            choices: {},
            allowCustom: true,
            minimum: 0,
            maximum: null,
            valueKey: "value",
            customKey: "custom"
        });
    }

    /* -------------------------------------------- */

    /**
     * Return a reference to the target attribute
     * @type {string}
     */
    get attribute() {
        return this.options.name;
    }

    /* -------------------------------------------- */

    /** @override */
    getData() {
        const attr = foundry.utils.getProperty(this.object.data, this.attribute);
        const o = this.options;
        const value = o.valueKey ? attr[o.valueKey] ?? [] : attr;
        const custom = o.customKey ? attr[o.customKey] ?? "" : "";

        // Populate choices
        const choices = Object.entries(o.choices).reduce((obj, e) => {
            let [k, v] = e;
            obj[k] = {label: v, chosen: attr ? value.includes(k) : false};
            return obj;
        }, {});

        // Return data
        return {
            allowCustom: o.allowCustom,
            choices: choices,
            custom: custom
        };
    }

    /* -------------------------------------------- */

    /** @override */
    async _updateObject(event, formData) {
        const o = this.options;

        // Obtain choices
        const chosen = [];
        for (let [k, v] of Object.entries(formData)) {
            if (k !== "custom" && v) chosen.push(k);
        }

        // Object including custom data
        const updateData = {};
        if (o.valueKey) updateData[`${this.attribute}.${o.valueKey}`] = chosen;
        else updateData[this.attribute] = chosen;
        if (o.allowCustom) updateData[`${this.attribute}.${o.customKey}`] = formData.custom;

        // Validate the number chosen
        if (o.minimum && chosen.length < o.minimum) {
            return ui.notifications.error(`You must choose at least ${o.minimum} options`);
        }
        if (o.maximum && chosen.length > o.maximum) {
            return ui.notifications.error(`You may choose no more than ${o.maximum} options`);
        }

        // Update the object
        this.object.update(updateData);
    }
}