Haketilo

/**

 * This file is part of Haketilo.

 *

 * Function: Install mappings/resources in Haketilo.

 *

 * Copyright (C) 2022 Wojtek Kosior

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation, either version 3 of the License, or

 * (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * As additional permission under GNU GPL version 3 section 7, you

 * may distribute forms of that code without the copy of the GNU

 * GPL normally required by section 4, provided you include this

 * license notice and, in case of non-source distribution, a URL

 * through which recipients can access the Corresponding Source.

 * If you modify file(s) with this exception, you may extend this

 * exception to your version of the file(s), but you are not

 * obligated to do so. If you do not wish to do so, delete this

 * exception statement from your version.

 *

 * As a special exception to the GPL, any HTML file which merely

 * makes function calls to this code, and for that purpose

 * includes it by reference shall be deemed a separate work for

 * copyright law purposes. If you modify this code, you may extend

 * this exception to your version of the code, but you are not

 * obligated to do so. If you do not wish to do so, delete this

 * exception statement from your version.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>.

 *

 * I, Wojtek Kosior, thereby promise not to sue for violation of this file's

 * license. Although I request that you do not make use of this code in a

 * proprietary program, I am not going to enforce this in court.

 */

#IMPORT common/indexeddb.js AS haketilodb

#IMPORT html/dialog.js

#IMPORT html/item_preview.js AS ip

#FROM common/browser.js   IMPORT browser

#FROM html/DOM_helpers.js IMPORT clone_template, Showable

#FROM common/entities.js  IMPORT item_id_string, version_string, get_files

#FROM common/misc.js      IMPORT sha256_async AS compute_sha256

const coll = new Intl.Collator();

/*

 * Comparator used to sort items in the order we want them to appear in

 * install dialog: first mappings alphabetically, then resources alphabetically.

 */

function compare_items(def1, def2) {

    if (def1.type !== def2.type)

	return def1.type === "mapping" ? -1 : 1;

    const name_comparison = coll.compare(def1.long_name, def2.long_name);

    return name_comparison === 0 ?

	coll.compare(def1.identifier, def2.identifier) : name_comparison;

}

function ItemEntry(install_view, item) {

    Object.assign(this, clone_template("install_list_entry"));

    this.item_def = item.def;

    this.item_name.innerText = item.def.long_name;

    this.item_id.innerText = item_id_string(item.def);

    if (item.db_def) {

	this.old_ver.innerText =

	    version_string(item.db_def.version, item.db_def.revision);

	this.update_info.classList.remove("hide");

    }

    let preview_cb = () => install_view.preview_item(item.def);

    preview_cb = install_view.dialog_ctx.when_hidden(preview_cb);

    this.details_but.addEventListener("click", preview_cb);

}

const container_ids = [

    "install_preview",

    "dialog_container",

    "mapping_preview_container",

    "resource_preview_container"

];

/*

 * Work object is used to communicate between asynchronously executing

 * functions when computing dependencies tree of an item and when fetching

 * files for installation.

 */

async function init_work() {

    const work = {

	waiting: 0,

	is_ok: true,

	db: (await haketilodb.get()),

	result: []

    };

    work.err = function (error, user_message) {

	if (error)

    	    console.error(error);

	work.is_ok = false;

	work.reject_cb(user_message);

    }

    return [work,

	    new Promise((...cbs) => [work.resolve_cb, work.reject_cb] = cbs)];

}

function _make_url_reg(item_type) {

    return new RegExp(

	`^https://hydrilla\\.koszko\\.org/schemas/api_${item_type}_description-1\\.([1-9][0-9]*\\.)*schema\\.json$`

    );

}

const _regexes = {};

function item_schema_url_regex(item_type) {

    _regexes[item_type] = _regexes[item_type] || _make_url_reg(item_type);

    return _regexes[item_type];

}

function InstallView(tab_id, on_view_show, on_view_hide) {

    Showable.call(this, on_view_show, on_view_hide);

    Object.assign(this, clone_template("install_view"));

    const show_container = name => {

	for (const cid of container_ids) {

	    if (cid !== name)

		this[cid].classList.add("hide");

	}

	this[name].classList.remove("hide");

    }

    this.dialog_ctx = dialog.make(() => show_container("dialog_container"),

				  () => show_container("install_preview"));

    this.dialog_container.prepend(this.dialog_ctx.main_div);

    /* Make a link to view a file from the repository. */

    const make_file_link = (preview_ctx, file_ref) => {

	const a = document.createElement("a");

	a.href = `${this.repo_url}file/sha256/${file_ref.sha256}`;

	a.innerText = file_ref.file;

	return a;

    }

    this.previews_ctx = {};

    this.preview_item = item_def => {

	if (!this.shown)

	    return;

	const fun = ip[`${item_def.type}_preview`];

	const preview_ctx = fun(item_def, this.previews_ctx[item_def.type],

				make_file_link);

	this.previews_ctx[item_def.type] = preview_ctx;

	const container_name = `${item_def.type}_preview_container`;

	show_container(container_name);

	this[container_name].prepend(preview_ctx.main_div);

    }

    let back_cb = () => show_container("install_preview");

    back_cb = this.dialog_ctx.when_hidden(back_cb);

    for (const type of ["resource", "mapping"])

	this[`${type}_back_but`].addEventListener("click", back_cb);

    const process_item = async (work, item_type, id, ver) => {

	if (!work.is_ok || work.processed_by_type[item_type].has(id))

	    return;

	work.processed_by_type[item_type].add(id);

	work.waiting++;

	const url = ver ?

	      `${this.repo_url}${item_type}/${id}/${ver.join(".")}.json` :

	      `${this.repo_url}${item_type}/${id}.json`;

	const response =

	      await browser.tabs.sendMessage(tab_id, ["repo_query", url]);

	if (!work.is_ok)

	    return;

	if ("error" in response) {

	    return work.err(response.error,

			    "Failure to communicate with repository :(");

	}

	if (!response.ok) {

	    return work.err(null,

			    `Repository sent HTTP code ${response.status} :(`);

	}

	if ("error_json" in response) {

	    return work.err(response.error_json,

			    "Repository's response is not valid JSON :(");

	}

	const captype = item_type[0].toUpperCase() + item_type.substring(1);

	const reg = item_schema_url_regex(item_type);

	if (!response.json["$schema"]) {

	    const msg = `${captype} ${item_id_string(id, ver)} was served using a nonconforming response format.`;

	    return work.err(null, msg);

	} else if (!reg.test(response.json["$schema"])) {

	    const msg = `${captype} ${item_id_string(id, ver)} was served using unsupported Hydrilla API version. You might need to update Haketilo.`;

	    return work.err(null, msg);

	}

	/* TODO: JSON schema validation should be added here. */

	const scripts = item_type === "resource" && response.json.scripts;

	const files = response.json.source_copyright.concat(scripts || []);

	if (item_type === "mapping") {

	    for (const res_ref of Object.values(response.json.payloads || {}))

		process_item(work, "resource", res_ref.identifier);

	} else {

	    for (const res_ref of (response.json.dependencies || []))

		process_item(work, "resource", res_ref.identifier);

	}

	/*

	 * At this point we already have JSON definition of the item and we

	 * triggered processing of its dependencies. We now have to verify if

	 * the same or newer version of the item is already present in the

	 * database and if so - omit this item.

	 */

	const transaction = work.db.transaction(item_type);

	try {

	    var db_def = await haketilodb.idb_get(transaction, item_type, id);

	    if (!work.is_ok)

		return;

	} catch(e) {

	    const msg = "Error accessing Haketilo's internal database :(";

	    return work.err(e, msg);

	}

	if (!db_def || db_def.version < response.json.version)

	    work.result.push({def: response.json, db_def});

	if (--work.waiting === 0)

	    work.resolve_cb(work.result);

    }

    async function compute_deps(item_type, item_id, item_ver) {

	const [work, work_prom] = await init_work();

	work.processed_by_type = {"mapping" : new Set(), "resource": new Set()};

	process_item(work, item_type, item_id, item_ver);

	const items = await work_prom;

	items.sort((i1, i2) => compare_items(i1.def, i2.def));

	return items;

    }

    const show_super = this.show;

    this.show = async (repo_url, item_type, item_id, item_ver) => {

	if (!show_super())

	    return;

	this.repo_url = repo_url;

	dialog.loader(this.dialog_ctx, "Fetching data from repository...");

	try {

	    var items = await compute_deps(item_type, item_id, item_ver);

	} catch(e) {

	    var dialog_prom = dialog.error(this.dialog_ctx, e);

	}

	if (!dialog_prom && items.length === 0) {

	    const msg = "Nothing to do - packages already installed.";

	    var dialog_prom = dialog.info(this.dialog_ctx, msg);

	}

	if (dialog_prom) {

	    dialog.close(this.dialog_ctx);

	    await dialog_prom;

	    this.hide();

	    return;

	}

	this.item_entries = items.map(i => new ItemEntry(this, i));

	this.to_install_list.append(...this.item_entries.map(ie => ie.main_li));

	dialog.close(this.dialog_ctx);

    }

    const process_file = async (work, sha256) => {

	if (!work.is_ok)

	    return;

	work.waiting++;

	try {

	    var file_uses = await haketilodb.idb_get(work.file_uses_transaction,

						     "file_uses", sha256);

	    if (!work.is_ok)

		return;

	} catch(e) {

	    const msg = "Error accessing Haketilo's internal database :(";

	    return work.err(e, msg);

	}

	if (!file_uses) {

	    const url = `${this.repo_url}file/sha256/${sha256}`;

	    try {

		var response = await fetch(url);

		if (!work.is_ok)

		    return;

	    } catch(e) {

		const msg = "Failure to communicate with repository :(";

		return work.err(e, msg);

	    }

	    if (!response.ok) {

		const msg = `Repository sent HTTP code ${response.status} :(`;

		return work.err(null, msg);

	    }

	    try {

		var text = await response.text();

		if (!work.is_ok)

		    return;

	    } catch(e) {

		const msg = "Repository's response is not valid text :(";

		return work.err(e, msg);

	    }

	    const digest = await compute_sha256(text);

	    if (!work.is_ok)

		return;

	    if (digest !== sha256) {

		const msg = `${url} served a file with different SHA256 cryptographic sum :(`;

		return work.err(null, msg);

	    }

	    work.result.push([sha256, text]);

	}

	if (--work.waiting === 0)

	    work.resolve_cb(work.result);

    }

    const get_missing_files = async item_defs => {

	const [work, work_prom] = await init_work();

	work.file_uses_transaction = work.db.transaction("file_uses");

	const processed_files = new Set();

	for (const item_def of item_defs) {

	    for (const file of get_files(item_def)) {

		if (!processed_files.has(file.sha256)) {

		    processed_files.add(file.sha256);

		    process_file(work, file.sha256);

		}

	    }

	}

	return processed_files.size > 0 ? work_prom : [];

    }

    const perform_install = async () => {

	if (!this.show || !this.item_entries)

	    return;

	dialog.loader(this.dialog_ctx, "Installing...");

	const item_defs = this.item_entries.map(ie => ie.item_def);

	try {

	    var files = (await get_missing_files(item_defs))

		.reduce((ac, [h, txt]) => Object.assign(ac, {[h]: txt}), {});

	} catch(e) {

	    var dialog_prom = dialog.error(this.dialog_ctx, e);

	}

	if (files !== undefined) {

	    const data = {file: {sha256: files}};

	    for (const type of ["resource", "mapping"]) {

		const set = {};

		for (const def of item_defs.filter(def => def.type === type))

		    set[def.identifier] = {[version_string(def.version)]: def};

		data[type] = set;

	    }

	    try {

		await haketilodb.save_items(data);

	    } catch(e) {

		console.error(e);

		const msg = "Error writing to Haketilo's internal database :(";

		var dialog_prom = dialog.error(this.dialog_ctx, msg);

	    }

	}

	if (!dialog_prom) {

	    const msg = "Successfully installed!";

	    var dialog_prom = dialog.info(this.dialog_ctx, msg);

	}

	dialog.close(this.dialog_ctx);

	await dialog_prom;

	this.hide();

    }

    const hide_super = this.hide;

    this.hide = () => {

	if (!hide_super())

	    return;

	delete this.item_entries;

	[...this.to_install_list.children].forEach(n => n.remove());

    }

    const hide_cb = this.dialog_ctx.when_hidden(this.hide);

    this.cancel_but.addEventListener("click", hide_cb);

    const install_cb = this.dialog_ctx.when_hidden(perform_install);

    this.install_but.addEventListener("click", install_cb);

}

#EXPORT InstallView