"use strict";

function get_user_ids_from_subs(items) {
    let user_ids = [];
    const stream_ids = items.map((item) => item.stream_id);
    for (const stream_id of stream_ids) {
        const sub = stream_data.get_sub_by_id(stream_id);
        if (!sub) {
            continue;
        }
        user_ids = user_ids.concat(sub.subscribers.map());
    }
    return user_ids;
}

exports.get_user_ids = function (pill_widget) {
    const items = pill_widget.items();
    let user_ids = get_user_ids_from_subs(items);
    user_ids = Array.from(new Set(user_ids));

    user_ids = user_ids.filter(Boolean);
    return user_ids;
};

exports.append_stream = function (stream, pill_widget) {
    pill_widget.appendValidatedData({
        display_value: "#" + stream.name + ": " + stream.subscriber_count + " users",
        stream_id: stream.stream_id,
    });
    pill_widget.clear_text();
};

exports.get_stream_ids = function (pill_widget) {
    const items = pill_widget.items();
    let stream_ids = items.map((item) => item.stream_id);
    stream_ids = stream_ids.filter(Boolean);

    return stream_ids;
};

exports.filter_taken_streams = function (items, pill_widget) {
    const taken_stream_ids = exports.get_stream_ids(pill_widget);
    items = items.filter((item) => !taken_stream_ids.includes(item.stream_id));
    return items;
};

exports.typeahead_source = function (pill_widget) {
    const potential_streams = stream_data.get_unsorted_subs();
    return exports.filter_taken_streams(potential_streams, pill_widget);
};

window.stream_pill = exports;