let message_type = false; // 'stream', 'private', or false-y

exports.set_message_type = function (msg_type) {
    message_type = msg_type;
};

exports.get_message_type = function () {
    return message_type;
};

exports.composing = function () {
    // This is very similar to get_message_type(), but it returns
    // a boolean.
    return !!message_type;
};

exports.focus_in_empty_compose = function () {
    return (
        exports.composing() &&
        exports.message_content() === "" &&
        $("#compose-textarea").is(":focus")
    );
};

function get_or_set(fieldname, keep_leading_whitespace) {
    // We can't hoist the assignment of 'elem' out of this lambda,
    // because the DOM element might not exist yet when get_or_set
    // is called.
    return function (newval) {
        const elem = $("#" + fieldname);
        const oldval = elem.val();
        if (newval !== undefined) {
            elem.val(newval);
        }
        return keep_leading_whitespace ? oldval.trimRight() : oldval.trim();
    };
}

// TODO: Break out setters and getter into their own functions.
exports.stream_name = get_or_set("stream_message_recipient_stream");
exports.topic = get_or_set("stream_message_recipient_topic");
// We can't trim leading whitespace in `compose_textarea` because
// of the indented syntax for multi-line code blocks.
exports.message_content = get_or_set("compose-textarea", true);
exports.private_message_recipient = function (value) {
    if (typeof value === "string") {
        compose_pm_pill.set_from_emails(value);
    } else {
        return compose_pm_pill.get_emails();
    }
};

exports.has_message_content = function () {
    return exports.message_content() !== "";
};

window.compose_state = exports;