/**
 * Myext display panel logic
 *
 * Copyright (C) 2021 Wojtek Kosior
 * Redistribution terms are gathered in the `copyright' file.
 */

/*
 * IMPORTS_START
 * IMPORT browser
 * IMPORT is_chrome
 * IMPORT is_mozilla
 * IMPORT CONNECTION_TYPE
 * IMPORT url_item
 * IMPORT is_privileged_url
 * IMPORT TYPE_PREFIX
 * IMPORT nice_name
 * IMPORT open_in_settings
 * IMPORT for_each_possible_pattern
 * IMPORTS_END
 */

function by_id(id)
{
    return document.getElementById(id);
}

const tab_query = {currentWindow: true, active: true};

async function get_current_tab()
{
    /* Fix for fact that Chrome does not use promises here */
    const promise = is_chrome ?
	  new Promise((resolve, reject) =>
		      browser.tabs.query(tab_query, tab => resolve(tab))) :
	  browser.tabs.query(tab_query);

    try {
	return (await promise)[0];
    } catch(e) {
	console.log(e);
    }
}

const page_url_heading = by_id("page_url_heading");
const show_privileged_notice_chbx = by_id("show_privileged_notice_chbx");
const show_page_state_chbx = by_id("show_page_state_chbx");

async function show_page_activity_info()
{
    const tab = await get_current_tab();

    if (tab === undefined) {
	page_url_heading.textContent = "unknown page";
	return;
    }

    const url = url_item(tab.url);
    page_url_heading.textContent = url;
    if (is_privileged_url(url)) {
	show_privileged_notice_chbx.checked = true;
	return;
    }

    populate_possible_patterns_list(url);
    show_page_state_chbx.checked = true;

    try_to_connect(tab.id);
}

function populate_possible_patterns_list(url)
{
    for_each_possible_pattern(url, add_pattern_to_list);

    const port = browser.runtime.connect({name: CONNECTION_TYPE.PAGE_INFO});
    port.onMessage.addListener(handle_page_info);
    port.postMessage(["subscribe", url]);
}

const possible_patterns_ul = by_id("possible_patterns");
const pattern_li_template = by_id("pattern_li_template");
pattern_li_template.removeAttribute("id");
const known_patterns = new Map();

function add_pattern_to_list(pattern)
{
    const li = pattern_li_template.cloneNode(true);
    li.id = `pattern_li_${known_patterns.size}`;
    known_patterns.set(pattern, li.id);

    const span = li.firstElementChild;
    span.textContent = pattern;

    const button = span.nextElementSibling;
    const settings_opener = () => open_in_settings(TYPE_PREFIX.PAGE, pattern);
    button.addEventListener("click", settings_opener);

    possible_patterns_ul.appendChild(li)

    return li.id;
}

function ensure_pattern_exists(pattern)
{
    let id = known_patterns.get(pattern);
    /*
     * As long as pattern computation works well, we should never get into this
     * conditional block. This is just a safety measure. To be removed as part
     * of a bigger rework when we start taking iframes into account.
     */
    if (id === undefined) {
	console.log(`unknown pattern: ${pattern}`);
	id = add_pattern_to_list(pattern);
    }

    return id;
}

function set_pattern_li_button_text(li_id, text)
{
    by_id(li_id).firstElementChild.nextElementSibling.textContent = text;
}

function handle_page_info(message)
{
    const [type, data] = message;

    if (type === "change") {
	const li_id = ensure_pattern_exists(data.item);
	if (data.old_val === undefined)
	    set_pattern_li_button_text(li_id, "Edit in settings");
	if (data.new_val === undefined)
	    set_pattern_li_button_text(li_id, "Add setting");
    }

    if (type === "new_url") {
	for (const li_id of known_patterns.values())
	    set_pattern_li_button_text(li_id, "Add setting");
	for (const [pattern, settings] of data) {
	    set_pattern_li_button_text(ensure_pattern_exists(pattern),
				       "Edit in settings")
	}
    }
}

const connected_chbx = by_id("connected_chbx");

function try_to_connect(tab_id)
{
    /* This won't connect to iframes. We'll add support for them later */
    const connect_info = {name: CONNECTION_TYPE.ACTIVITY_INFO, frameId: 0};
    const port = browser.tabs.connect(tab_id, connect_info);

    port.onDisconnect.addListener(port => handle_disconnect(tab_id));
    port.onMessage.addListener(handle_activity_report);

    if (is_mozilla)
	setTimeout(() => monitor_connecting(port, tab_id), 1000);
}

const loading_chbx = by_id("loading_chbx");

function handle_disconnect(tab_id)
{
    if (is_chrome && !browser.runtime.lastError)
	return;

    /* return if there was no connection initialization failure */
    if (connected_chbx.checked)
	return;

    loading_chbx.checked = !loading_chbx.checked;
    setTimeout(() => try_to_connect(tab_id), 1000);
}

function monitor_connecting(port, tab_id)
{
    if (connected_chbx.checked)
	return;

    port.disconnect();
    loading_chbx.checked = !loading_chbx.checked;
    try_to_connect(tab_id);
}

const pattern_span = by_id("pattern");
const view_pattern_but = by_id("view_pattern");
const blocked_span = by_id("blocked");
const payload_span = by_id("payload");
const view_payload_but = by_id("view_payload");
const container_for_injected = by_id("container_for_injected");

function handle_activity_report(message)
{
    connected_chbx.checked = true;

    const [type, data] = message;

    if (type === "settings") {
	let [pattern, settings] = data;

	settings = settings || {};
	blocked_span.textContent = settings.allow ? "no" : "yes";

	if (pattern) {
	    pattern_span.textContent = pattern;
	    const settings_opener =
		  () => open_in_settings(TYPE_PREFIX.PAGE, pattern);
	    view_pattern_but.classList.remove("hide");
	    view_pattern_but.addEventListener("click", settings_opener);
	} else {
	    pattern_span.textContent = "none";
	}

	const components = settings.components;
	if (components) {
	    payload_span.textContent = nice_name(...components);
	    const settings_opener = () => open_in_settings(...components);
	    view_payload_but.classList.remove("hide");
	    view_payload_but.addEventListener("click", settings_opener);
	} else {
	    payload_span.textContent = "none";
	}
    }
    if (type === "script") {
	const h4 = document.createElement("h4");
	const pre = document.createElement("pre");
	h4.textContent = "script";
	pre.textContent = data;

	container_for_injected.appendChild(h4);
	container_for_injected.appendChild(pre);
    }
}

by_id("settings_but")
    .addEventListener("click", (e) => browser.runtime.openOptionsPage());

show_page_activity_info();