import _ from "lodash";

import render_compose_notification from "../templates/compose_notification.hbs";
import render_notification from "../templates/notification.hbs";

import * as alert_words from "./alert_words";
import * as channel from "./channel";
import * as favicon from "./favicon";
import * as message_store from "./message_store";
import * as muting from "./muting";
import * as narrow_state from "./narrow_state";
import * as navigate from "./navigate";
import * as people from "./people";
import * as settings_config from "./settings_config";
import * as spoilers from "./spoilers";
import * as stream_data from "./stream_data";
import * as stream_ui_updates from "./stream_ui_updates";

const notice_memory = new Map();

// When you start Zulip, window_focused should be true, but it might not be the
// case after a server-initiated reload.
let window_focused = document.hasFocus && document.hasFocus();

let supports_sound;

let NotificationAPI;

export function set_notification_api(n) {
    NotificationAPI = n;
}

if (window.electron_bridge && window.electron_bridge.new_notification) {
    class ElectronBridgeNotification extends EventTarget {
        constructor(title, options) {
            super();
            Object.assign(
                this,
                window.electron_bridge.new_notification(title, options, (type, eventInit) =>
                    this.dispatchEvent(new Event(type, eventInit)),
                ),
            );
        }

        static get permission() {
            return Notification.permission;
        }

        static async requestPermission(callback) {
            if (callback) {
                callback(await Promise.resolve(Notification.permission));
            }
            return Notification.permission;
        }
    }

    NotificationAPI = ElectronBridgeNotification;
} else if (window.Notification) {
    NotificationAPI = window.Notification;
}

export function get_notifications() {
    return notice_memory;
}

function get_audio_file_path(audio_element, audio_file_without_extension) {
    if (audio_element.canPlayType('audio/ogg; codecs="vorbis"')) {
        return audio_file_without_extension + ".ogg";
    }

    return audio_file_without_extension + ".mp3";
}

export function initialize() {
    $(window)
        .on("focus", () => {
            window_focused = true;

            for (const notice_mem_entry of notice_memory.values()) {
                notice_mem_entry.obj.close();
            }
            notice_memory.clear();

            // Update many places on the DOM to reflect unread
            // counts.
            unread_ops.process_visible();
        })
        .on("blur", () => {
            window_focused = false;
        });

    const audio = $("<audio>");
    if (audio[0].canPlayType === undefined) {
        supports_sound = false;
    } else {
        supports_sound = true;

        $("#notifications-area").append(audio);
        audio.append($("<source>").attr("loop", "yes"));
        const source = $("#notifications-area audio source");

        if (audio[0].canPlayType('audio/ogg; codecs="vorbis"')) {
            source.attr("type", "audio/ogg");
        } else {
            source.attr("type", "audio/mpeg");
        }

        const audio_file_without_extension =
            "/static/audio/notification_sounds/" + page_params.notification_sound;
        source.attr("src", get_audio_file_path(audio[0], audio_file_without_extension));
    }
}

function update_notification_sound_source() {
    // Simplified version of the source creation in `exports.initialize`, for
    // updating the source instead of creating it for the first time.
    const audio = $("#notifications-area audio");
    const source = $("#notifications-area audio source");
    const audio_file_without_extension =
        "/static/audio/notification_sounds/" + page_params.notification_sound;
    source.attr("src", get_audio_file_path(audio[0], audio_file_without_extension));

    // Load it so that it is ready to be played; without this the old sound
    // is played.
    $("#notifications-area").find("audio")[0].load();
}

export function permission_state() {
    if (NotificationAPI === undefined) {
        // act like notifications are blocked if they do not have access to
        // the notification API.
        return "denied";
    }
    return NotificationAPI.permission;
}

let unread_count = 0;
let pm_count = 0;

export function redraw_title() {
    // Update window title to reflect unread messages in current view
    const new_title =
        (unread_count ? "(" + unread_count + ") " : "") +
        narrow.narrow_title +
        " - " +
        page_params.realm_name +
        " - " +
        "Zulip";

    document.title = new_title;
}

export function update_unread_counts(new_unread_count, new_pm_count) {
    if (new_unread_count === unread_count && new_pm_count === pm_count) {
        return;
    }

    unread_count = new_unread_count;
    pm_count = new_pm_count;

    // Indicate the message count in the favicon
    favicon.update_favicon(unread_count, pm_count);

    // Notify the current desktop app's UI about the new unread count.
    if (window.electron_bridge !== undefined) {
        window.electron_bridge.send_event("total_unread_count", unread_count);
    }

    // TODO: Add a `window.electron_bridge.updatePMCount(new_pm_count);` call?

    redraw_title();
}

export function is_window_focused() {
    return window_focused;
}

function in_browser_notify(message, title, content, raw_operators, opts) {
    const notification_html = $(
        render_notification({
            gravatar_url: people.small_avatar_url(message),
            title,
            content,
            message_id: message.id,
        }),
    );

    $(".top-right")
        .notify({
            message: {
                html: notification_html,
            },
            fadeOut: {
                enabled: true,
                delay: 4000,
            },
        })
        .show();

    $(`.notification[data-message-id='${CSS.escape(message.id)}']`)
        .expectOne()
        .data("narrow", {
            raw_operators,
            opts_notif: opts,
        });
}

export function notify_above_composebox(note, link_class, link_msg_id, link_text) {
    const notification_html = $(
        render_compose_notification({
            note,
            link_class,
            link_msg_id,
            link_text,
        }),
    );
    clear_compose_notifications();
    $("#out-of-view-notification").append(notification_html);
    $("#out-of-view-notification").show();
}

if (window.electron_bridge !== undefined) {
    // The code below is for sending a message received from notification reply which
    // is often referred to as inline reply feature. This is done so desktop app doesn't
    // have to depend on channel.post for setting crsf_token and narrow.by_topic
    // to narrow to the message being sent.
    if (window.electron_bridge.set_send_notification_reply_message_supported !== undefined) {
        window.electron_bridge.set_send_notification_reply_message_supported(true);
    }
    window.electron_bridge.on_event("send_notification_reply_message", (message_id, reply) => {
        const message = message_store.get(message_id);
        const data = {
            type: message.type,
            content: reply,
            to: message.type === "private" ? message.reply_to : message.stream,
            topic: message.topic,
        };

        function success() {
            if (message.type === "stream") {
                narrow.by_topic(message_id, {trigger: "desktop_notification_reply"});
            } else {
                narrow.by_recipient(message_id, {trigger: "desktop_notification_reply"});
            }
        }

        function error(error) {
            window.electron_bridge.send_event("send_notification_reply_message_failed", {
                data,
                message_id,
                error,
            });
        }

        channel.post({
            url: "/json/messages",
            data,
            success,
            error,
        });
    });
}

export function process_notification(notification) {
    let i;
    let notification_object;
    let key;
    let content;
    let other_recipients;
    const message = notification.message;
    let title = message.sender_full_name;
    let msg_count = 1;
    let notification_source;
    let raw_operators = [];
    const opts = {trigger: "notification click"};
    // Convert the content to plain text, replacing emoji with their alt text
    content = $("<div/>").html(message.content);
    ui.replace_emoji_with_text(content);
    spoilers.hide_spoilers_in_notification(content);
    content = content.text();

    const topic = message.topic;

    if (message.is_me_message) {
        content = message.sender_full_name + content.slice(3);
    }

    if (message.type === "private" || message.type === "test-notification") {
        if (
            page_params.pm_content_in_desktop_notifications !== undefined &&
            !page_params.pm_content_in_desktop_notifications
        ) {
            content = "New private message from " + message.sender_full_name;
        }
        key = message.display_reply_to;
        other_recipients = message.display_reply_to;
        // Remove the sender from the list of other recipients
        other_recipients = other_recipients.replace(", " + message.sender_full_name, "");
        other_recipients = other_recipients.replace(message.sender_full_name + ", ", "");
        notification_source = "pm";
    } else {
        key = message.sender_full_name + " to " + message.stream + " > " + topic;
        if (message.mentioned) {
            notification_source = "mention";
        } else if (message.alerted) {
            notification_source = "alert";
        } else {
            notification_source = "stream";
        }
    }
    blueslip.debug("Desktop notification from source " + notification_source);

    if (content.length > 150) {
        // Truncate content at a word boundary
        for (i = 150; i > 0; i -= 1) {
            if (content[i] === " ") {
                break;
            }
        }
        content = content.slice(0, i);
        content += " [...]";
    }

    if (notice_memory.has(key)) {
        msg_count = notice_memory.get(key).msg_count + 1;
        title = msg_count + " messages from " + title;
        notification_object = notice_memory.get(key).obj;
        notification_object.close();
    }

    if (message.type === "private") {
        if (message.display_recipient.length > 2) {
            // If the message has too many recipients to list them all...
            if (content.length + title.length + other_recipients.length > 230) {
                // Then count how many people are in the conversation and summarize
                // by saying the conversation is with "you and [number] other people"
                other_recipients = other_recipients.replace(/[^,]/g, "").length + " other people";
            }

            title += " (to you and " + other_recipients + ")";
        } else {
            title += " (to you)";
        }

        raw_operators = [{operand: message.reply_to, operator: "pm-with"}];
    }

    if (message.type === "stream") {
        title += " (to " + message.stream + " > " + topic + ")";
        raw_operators = [
            {operator: "stream", operand: message.stream},
            {operator: "topic", operand: topic},
        ];
    }

    if (notification.desktop_notify) {
        const icon_url = people.small_avatar_url(message);
        notification_object = new NotificationAPI(title, {
            icon: icon_url,
            body: content,
            tag: message.id,
        });
        notice_memory.set(key, {
            obj: notification_object,
            msg_count,
            message_id: message.id,
        });

        if (_.isFunction(notification_object.addEventListener)) {
            // Sadly, some third-party Electron apps like Franz/Ferdi
            // misimplement the Notification API not inheriting from
            // EventTarget.  This results in addEventListener being
            // unavailable for them.
            notification_object.addEventListener("click", () => {
                notification_object.close();
                if (message.type !== "test-notification") {
                    narrow.by_topic(message.id, {trigger: "notification"});
                }
                window.focus();
            });
            notification_object.addEventListener("close", () => {
                notice_memory.delete(key);
            });
        }
    } else {
        in_browser_notify(message, title, content, raw_operators, opts);
    }
}

export function close_notification(message) {
    for (const [key, notice_mem_entry] of notice_memory) {
        if (notice_mem_entry.message_id === message.id) {
            notice_mem_entry.obj.close();
            notice_memory.delete(key);
        }
    }
}

export function message_is_notifiable(message) {
    // Independent of the user's notification settings, are there
    // properties of the message that unconditionally mean we
    // shouldn't notify about it.

    if (message.sent_by_me) {
        return false;
    }

    // If a message is edited multiple times, we want to err on the side of
    // not spamming notifications.
    if (message.notification_sent) {
        return false;
    }

    // @-<username> mentions take precedence over muted-ness. Note
    // that @all mentions are still suppressed by muting.
    if (message.mentioned_me_directly) {
        return true;
    }

    // Messages to muted streams that don't mention us specifically
    // are not notifiable.
    if (message.type === "stream" && stream_data.is_muted(message.stream_id)) {
        return false;
    }

    if (message.type === "stream" && muting.is_topic_muted(message.stream_id, message.topic)) {
        return false;
    }

    // Everything else is on the table; next filter based on notification
    // settings.
    return true;
}

export function should_send_desktop_notification(message) {
    // Always notify for testing notifications.
    if (message.type === "test-notification") {
        return true;
    }

    // For streams, send if desktop notifications are enabled for all
    // message on this stream.
    if (
        message.type === "stream" &&
        stream_data.receives_notifications(message.stream_id, "desktop_notifications")
    ) {
        return true;
    }

    // enable_desktop_notifications determines whether we pop up a
    // notification for PMs/mentions/alerts
    if (!page_params.enable_desktop_notifications) {
        return false;
    }

    // And then we need to check if the message is a PM, mention,
    // wildcard mention with wildcard_mentions_notify, or alert.
    if (message.type === "private") {
        return true;
    }

    if (alert_words.notifies(message)) {
        return true;
    }

    if (message.mentioned_me_directly) {
        return true;
    }

    // wildcard mentions
    if (
        message.mentioned &&
        stream_data.receives_notifications(message.stream_id, "wildcard_mentions_notify")
    ) {
        return true;
    }

    return false;
}

export function should_send_audible_notification(message) {
    // For streams, ding if sounds are enabled for all messages on
    // this stream.
    if (
        message.type === "stream" &&
        stream_data.receives_notifications(message.stream_id, "audible_notifications")
    ) {
        return true;
    }

    // enable_sounds determines whether we ding for PMs/mentions/alerts
    if (!page_params.enable_sounds) {
        return false;
    }

    // And then we need to check if the message is a PM, mention,
    // wildcard mention with wildcard_mentions_notify, or alert.
    if (message.type === "private" || message.type === "test-notification") {
        return true;
    }

    if (alert_words.notifies(message)) {
        return true;
    }

    if (message.mentioned_me_directly) {
        return true;
    }

    // wildcard mentions
    if (
        message.mentioned &&
        stream_data.receives_notifications(message.stream_id, "wildcard_mentions_notify")
    ) {
        return true;
    }

    return false;
}

export function granted_desktop_notifications_permission() {
    return NotificationAPI && NotificationAPI.permission === "granted";
}

export function request_desktop_notifications_permission() {
    if (NotificationAPI) {
        NotificationAPI.requestPermission();
    }
}

export function received_messages(messages) {
    for (const message of messages) {
        if (!message_is_notifiable(message)) {
            continue;
        }
        if (!unread.message_unread(message)) {
            // The message is already read; Zulip is currently in focus.
            continue;
        }

        message.notification_sent = true;

        if (should_send_desktop_notification(message)) {
            process_notification({
                message,
                desktop_notify: granted_desktop_notifications_permission(),
            });
        }
        if (should_send_audible_notification(message) && supports_sound) {
            $("#notifications-area").find("audio")[0].play();
        }
    }
}

export function send_test_notification(content) {
    received_messages([
        {
            id: Math.random(),
            type: "test-notification",
            sender_email: "notification-bot@zulip.com",
            sender_full_name: "Notification Bot",
            display_reply_to: "Notification Bot",
            content,
            unread: true,
        },
    ]);
}

// Note that this returns values that are not HTML-escaped, for use in
// handlebars templates that will do further escaping.
function get_message_header(message) {
    if (message.type === "stream") {
        return message.stream + " > " + message.topic;
    }
    if (message.display_recipient.length > 2) {
        return i18n.t("group private messages with __- recipient__", {
            recipient: message.display_reply_to,
        });
    }
    if (people.is_current_user(message.reply_to)) {
        return i18n.t("private messages with yourself");
    }
    return i18n.t("private messages with __- recipient__", {recipient: message.display_reply_to});
}

export function get_local_notify_mix_reason(message) {
    const row = current_msg_list.get_row(message.id);
    if (row.length > 0) {
        // If our message is in the current message list, we do
        // not have a mix, so we are happy.
        return undefined;
    }

    if (message.type === "stream" && muting.is_topic_muted(message.stream_id, message.topic)) {
        return i18n.t("Sent! Your message was sent to a topic you have muted.");
    }

    if (message.type === "stream" && stream_data.is_muted(message.stream_id)) {
        return i18n.t("Sent! Your message was sent to a stream you have muted.");
    }

    // offscreen because it is outside narrow
    // we can only look for these on non-search (can_apply_locally) messages
    // see also: exports.notify_messages_outside_current_search
    const current_filter = narrow_state.filter();
    if (
        current_filter &&
        current_filter.can_apply_locally() &&
        !current_filter.predicate()(message)
    ) {
        return i18n.t("Sent! Your message is outside your current narrow.");
    }

    return undefined;
}

export function notify_local_mixes(messages, need_user_to_scroll) {
    /*
        This code should only be called when we are displaying
        messages sent by current client. It notifies users that
        their messages aren't actually in the view that they
        composed to.

        This code is called after we insert messages into our
        message list widgets. All of the conditions here are
        checkable locally, so we may want to execute this code
        earlier in the codepath at some point and possibly punt
        on local rendering.

        Possible cleanup: Arguably, we should call this function
        unconditionally and just check if message.local_id is in
        sent_messages.messages here.
    */

    for (const message of messages) {
        if (!people.is_my_user_id(message.sender_id)) {
            // This can happen if the client is offline for a while
            // around the time this client sends a message; see the
            // caller of message_events.insert_new_messages.
            blueslip.info(
                "Slightly unexpected: A message not sent by us batches with those that were.",
            );
            continue;
        }

        let reason = get_local_notify_mix_reason(message);

        if (!reason) {
            if (need_user_to_scroll) {
                reason = i18n.t("Sent! Scroll down to view your message.");
                notify_above_composebox(reason, "", null, "");
                setTimeout(() => {
                    $("#out-of-view-notification").hide();
                }, 3000);
            }

            // This is the HAPPY PATH--for most messages we do nothing
            // other than maybe sending the above message.
            continue;
        }

        const link_msg_id = message.id;
        const link_class = "compose_notification_narrow_by_topic";
        const link_text = i18n.t("Narrow to __- message_recipient__", {
            message_recipient: get_message_header(message),
        });

        notify_above_composebox(reason, link_class, link_msg_id, link_text);
    }
}

// for callback when we have to check with the server if a message should be in
// the current_msg_list (!can_apply_locally; a.k.a. "a search").
export function notify_messages_outside_current_search(messages) {
    for (const message of messages) {
        if (!people.is_current_user(message.sender_email)) {
            continue;
        }
        const link_text = i18n.t("Narrow to __- message_recipient__", {
            message_recipient: get_message_header(message),
        });
        notify_above_composebox(
            i18n.t("Sent! Your recent message is outside the current search."),
            "compose_notification_narrow_by_topic",
            message.id,
            link_text,
        );
    }
}

export function clear_compose_notifications() {
    $("#out-of-view-notification").empty();
    $("#out-of-view-notification").stop(true, true);
    $("#out-of-view-notification").hide();
}

export function reify_message_id(opts) {
    const old_id = opts.old_id;
    const new_id = opts.new_id;

    // If a message ID that we're currently storing (as a link) has changed,
    // update that link as well
    for (const e of $("#out-of-view-notification a")) {
        const elem = $(e);
        const message_id = elem.data("message-id");

        if (message_id === old_id) {
            elem.data("message-id", new_id);
        }
    }
}

export function register_click_handlers() {
    $("#out-of-view-notification").on("click", ".compose_notification_narrow_by_topic", (e) => {
        const message_id = $(e.currentTarget).data("message-id");
        narrow.by_topic(message_id, {trigger: "compose_notification"});
        e.stopPropagation();
        e.preventDefault();
    });
    $("#out-of-view-notification").on("click", ".compose_notification_scroll_to_message", (e) => {
        const message_id = $(e.currentTarget).data("message-id");
        current_msg_list.select_id(message_id);
        navigate.scroll_to_selected();
        e.stopPropagation();
        e.preventDefault();
    });
    $("#out-of-view-notification").on("click", ".out-of-view-notification-close", (e) => {
        clear_compose_notifications();
        e.stopPropagation();
        e.preventDefault();
    });
}

export function handle_global_notification_updates(notification_name, setting) {
    // Update the global settings checked when determining if we should notify
    // for a given message. These settings do not affect whether or not a
    // particular stream should receive notifications.
    if (settings_config.all_notification_settings.includes(notification_name)) {
        page_params[notification_name] = setting;
    }

    if (settings_config.stream_notification_settings.includes(notification_name)) {
        notification_name = notification_name.replace("enable_stream_", "");
        stream_ui_updates.update_notification_setting_checkbox(notification_name);
    }

    if (notification_name === "notification_sound") {
        // Change the sound source with the new page `notification_sound`.
        update_notification_sound_source();
    }
}