From 235ef235883f375ee303aee283dc5e694b298248 Mon Sep 17 00:00:00 2001
From: Ned <7358345+nedpals@users.noreply.github.com>
Date: Mon, 11 Jul 2022 01:27:50 +0800
Subject: [PATCH] tools: add `v ls` - a VLS launcher and updater utility
 (#15009)

---
 CHANGELOG.md          |   1 +
 cmd/tools/vcomplete.v |   1 +
 cmd/tools/vls.v       | 442 ++++++++++++++++++++++++++++++++++++++++++
 cmd/v/help/ls.txt     |  18 ++
 cmd/v/v.v             |   1 +
 5 files changed, 463 insertions(+)
 create mode 100644 cmd/tools/vls.v
 create mode 100644 cmd/v/help/ls.txt

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 553359bf2..50b313c63 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@
 - DOOM is now translated/compiled and launched on CI servers. A screenshot of the running game
   is made via `vgret` and is compared to the expected result.
 - VLS performance improvements, especially on Windows.
+- Add `v ls` tool for installing, for updating, and for launching VLS (V Language Server)
 
 ## V 0.3
 *30 Jun 2022*
diff --git a/cmd/tools/vcomplete.v b/cmd/tools/vcomplete.v
index 8f12faadd..d36ea9f7c 100644
--- a/cmd/tools/vcomplete.v
+++ b/cmd/tools/vcomplete.v
@@ -95,6 +95,7 @@ const (
 		'doctor',
 		'fmt',
 		'gret',
+		'ls',
 		'repl',
 		'self',
 		'setup-freetype',
diff --git a/cmd/tools/vls.v b/cmd/tools/vls.v
new file mode 100644
index 000000000..d9fac3fe9
--- /dev/null
+++ b/cmd/tools/vls.v
@@ -0,0 +1,442 @@
+// Copyright (c) 2022 Ned Palacios. All rights reserved.
+// Use of this source code is governed by an MIT license
+// that can be found in the LICENSE file.
+//
+// The V language server launcher and updater utility is
+// a program responsible for installing, updating, and
+// executing the V language server program with the primary
+// goal of simplifying the installation process across
+// all different platforms, text editors, and IDEs.
+module main
+
+import os
+import flag
+import x.json2
+import net.http
+import runtime
+import crypto.sha256
+import time
+
+enum UpdateSource {
+	github_releases
+	git_repo
+}
+
+enum SetupKind {
+	none_
+	install
+	update
+}
+
+enum OutputMode {
+	silent
+	text
+	json
+}
+
+struct VlsUpdater {
+mut:
+	output        OutputMode   = .text
+	setup_kind    SetupKind    = .none_
+	update_source UpdateSource = .github_releases
+	ls_path       string // --path
+	pass_to_ls    bool   // --ls
+	is_check      bool   // --check
+	is_force      bool   // --force
+	is_help       bool   // --help
+	args          []string
+}
+
+const vls_folder = os.join_path(os.home_dir(), '.vls')
+
+const vls_bin_folder = os.join_path(vls_folder, 'bin')
+
+const vls_cache_folder = os.join_path(vls_folder, '.cache')
+
+const vls_manifest_path = os.join_path(vls_folder, 'vls.config.json')
+
+const vls_src_folder = os.join_path(vls_folder, 'src')
+
+const json_enc = json2.Encoder{
+	newline: `\n`
+	newline_spaces_count: 2
+	escape_unicode: false
+}
+
+fn (upd VlsUpdater) check_or_create_vls_folder() ? {
+	if !os.exists(vls_folder) {
+		upd.log('Creating .vls folder...')
+		os.mkdir(vls_folder)?
+	}
+}
+
+fn (upd VlsUpdater) manifest_config() ?map[string]json2.Any {
+	manifest_buf := os.read_file(vls_manifest_path) or { '{}' }
+	manifest_contents := json2.raw_decode(manifest_buf)?.as_map()
+	return manifest_contents
+}
+
+fn (upd VlsUpdater) exec_asset_file_name() string {
+	// TODO: support for Arm and other archs
+	os_name := os.user_os()
+	arch := if runtime.is_64bit() { 'x64' } else { 'x86' }
+	ext := if os_name == 'windows' { '.exe' } else { '' }
+	return 'vls_${os_name}_${arch + ext}'
+}
+
+fn (upd VlsUpdater) update_manifest(new_path string, from_source bool, timestamp time.Time) ? {
+	upd.log('Updating permissions...')
+	os.chmod(new_path, 755)?
+
+	upd.log('Updating vls.config.json...')
+	mut manifest := upd.manifest_config() or {
+		map[string]json2.Any{}
+	}
+
+	$if macos {
+		if os.exists(vls_manifest_path) {
+			os.rm(vls_manifest_path) or {}
+		}
+	}
+
+	mut manifest_file := os.open_file(vls_manifest_path, 'w+')?
+	defer {
+		manifest_file.close()
+	}
+
+	manifest['server_path'] = json2.Any(new_path)
+	manifest['last_updated'] = json2.Any(timestamp.format_ss())
+	manifest['from_source'] = json2.Any(from_source)
+
+	json_enc.encode_value(manifest, mut manifest_file)?
+}
+
+fn (upd VlsUpdater) init_download_prebuilt() ? {
+	if !os.exists(vls_cache_folder) {
+		os.mkdir(vls_cache_folder)?
+	}
+
+	if os.exists(vls_bin_folder) {
+		os.rmdir_all(vls_bin_folder)?
+	}
+
+	os.mkdir(vls_bin_folder)?
+}
+
+fn (upd VlsUpdater) get_last_updated_at() ?time.Time {
+	if manifest := upd.manifest_config() {
+		if 'last_updated' in manifest {
+			return time.parse(manifest['last_updated'] or { '' }.str()) or { return none }
+		}
+	}
+	return none
+}
+
+fn (upd VlsUpdater) download_prebuilt() ? {
+	last_updated_at := upd.get_last_updated_at() or { time.now() }
+	defer {
+		os.rmdir_all(vls_cache_folder) or {}
+	}
+
+	upd.log('Finding prebuilt executables from GitHub release..')
+	resp := http.get('https://api.github.com/repos/vlang/vls/releases')?
+	releases_json := json2.raw_decode(resp.body)?.arr()
+	if releases_json.len == 0 {
+		return error('Unable to fetch latest VLS release data: No releases found.')
+	}
+
+	latest_release := releases_json[0].as_map()
+	assets := latest_release['assets']?.arr()
+
+	mut checksum_asset_idx := -1
+	mut exec_asset_idx := -1
+
+	exp_asset_name := upd.exec_asset_file_name()
+	exec_asset_file_path := os.join_path(vls_cache_folder, exp_asset_name)
+
+	for asset_idx, raw_asset in assets {
+		asset := raw_asset.as_map()
+		match asset['name']?.str() {
+			exp_asset_name {
+				exec_asset_idx = asset_idx
+
+				// check timestamp here
+			}
+			'checksums.txt' {
+				checksum_asset_idx = asset_idx
+			}
+			else {}
+		}
+	}
+
+	if exec_asset_idx == -1 {
+		return error_with_code('No executable found for this system.', 100)
+	} else if checksum_asset_idx == -1 {
+		return error('Unable to download executable: missing checksum')
+	}
+
+	exec_asset := assets[exec_asset_idx].as_map()
+
+	mut asset_last_updated_at := time.now()
+	if created_at := exec_asset['created_at'] {
+		asset_last_updated_at = time.parse_rfc3339(created_at.str()) or { asset_last_updated_at }
+	}
+
+	if !upd.is_force && asset_last_updated_at <= last_updated_at {
+		upd.log("VLS was already updated to it's latest version.")
+		return
+	}
+
+	upd.log('Executable found for this system. Downloading...')
+	upd.init_download_prebuilt()?
+	http.download_file(exec_asset['browser_download_url']?.str(), exec_asset_file_path)?
+
+	checksum_file_path := os.join_path(vls_cache_folder, 'checksums.txt')
+	checksum_file_asset := assets[checksum_asset_idx].as_map()
+	http.download_file(checksum_file_asset['browser_download_url']?.str(), checksum_file_path)?
+	checksums := os.read_file(checksum_file_path)?.split_into_lines()
+
+	upd.log('Verifying checksum...')
+	for checksum_result in checksums {
+		if checksum_result.ends_with(exp_asset_name) {
+			checksum := checksum_result.split(' ')[0]
+			actual := calculate_checksum(exec_asset_file_path) or { '' }
+			if checksum != actual {
+				return error('Downloaded executable is corrupted. Exiting...')
+			}
+			break
+		}
+	}
+
+	new_exec_path := os.join_path(vls_bin_folder, exp_asset_name)
+	os.cp(exec_asset_file_path, new_exec_path)?
+	upd.update_manifest(new_exec_path, false, asset_last_updated_at) or {
+		upd.log('Unable to update config but the executable was updated successfully.')
+	}
+	upd.print_new_vls_version(new_exec_path)
+}
+
+fn (upd VlsUpdater) print_new_vls_version(new_vls_exec_path string) {
+	exec_version := os.execute('$new_vls_exec_path --version')
+	if exec_version.exit_code == 0 {
+		upd.log('VLS was updated to version: ${exec_version.output.all_after('vls version ').trim_space()}')
+	}
+}
+
+fn calculate_checksum(file_path string) ?string {
+	data := os.read_file(file_path)?
+	return sha256.hexhash(data)
+}
+
+fn (upd VlsUpdater) compile_from_source() ? {
+	git := os.find_abs_path_of_executable('git') or { return error('Git not found.') }
+
+	if !os.exists(vls_src_folder) {
+		upd.log('Cloning VLS repo...')
+		clone_result := os.execute('$git clone https://github.com/nedpals/vls $vls_src_folder')
+		if clone_result.exit_code != 0 {
+			return error('Failed to build VLS from source. Reason: $clone_result.output')
+		}
+	} else {
+		upd.log('Updating VLS repo...')
+		pull_result := os.execute('$git -C $vls_src_folder pull')
+		if !upd.is_force && pull_result.output.trim_space() == 'Already up to date.' {
+			upd.log("VLS was already updated to it's latest version.")
+			return
+		}
+	}
+
+	upd.log('Compiling VLS from source...')
+	possible_compilers := ['cc', 'gcc', 'clang', 'msvc']
+	mut selected_compiler_idx := -1
+
+	for i, cname in possible_compilers {
+		os.find_abs_path_of_executable(cname) or { continue }
+		selected_compiler_idx = i
+		break
+	}
+
+	if selected_compiler_idx == -1 {
+		return error('Cannot compile VLS from source: no appropriate C compiler found.')
+	}
+
+	compile_result := os.execute('v run ${os.join_path(vls_src_folder, 'build.vsh')} ${possible_compilers[selected_compiler_idx]}')
+	if compile_result.exit_code != 0 {
+		return error('Cannot compile VLS from source: $compile_result.output')
+	}
+
+	exec_path := os.join_path(vls_src_folder, 'bin', 'vls')
+	upd.update_manifest(exec_path, true, time.now()) or {
+		upd.log('Unable to update config but the executable was updated successfully.')
+	}
+	upd.print_new_vls_version(exec_path)
+}
+
+fn (upd VlsUpdater) find_ls_path() ?string {
+	manifest := upd.manifest_config()?
+	if 'server_path' in manifest {
+		server_path := manifest['server_path']?
+		if server_path is string {
+			return server_path
+		}
+	}
+	return none
+}
+
+fn (mut upd VlsUpdater) parse(mut fp flag.FlagParser) ? {
+	is_json := fp.bool('json', ` `, false, 'Print the output as JSON.')
+	if is_json {
+		upd.output = .json
+	}
+
+	is_silent := fp.bool('silent', ` `, false, 'Disables output printing.')
+	if is_silent && is_json {
+		return error('Cannot use --json and --silent at the same time.')
+	} else if is_silent {
+		upd.output = .silent
+	}
+
+	is_install := fp.bool('install', ` `, false, 'Installs the language server. You may also use this flag to re-download or force update your existing installation.')
+	is_update := fp.bool('update', ` `, false, 'Updates the installed language server.')
+	upd.is_check = fp.bool('check', ` `, false, 'Checks if the language server is installed.')
+	upd.is_force = fp.bool('force', ` `, false, 'Force install or update the language server.')
+	is_source := fp.bool('source', ` `, false, 'Clone and build the language server from source.')
+
+	if is_install && is_update {
+		return error('Cannot use --install and --update at the same time.')
+	} else if is_install {
+		upd.setup_kind = .install
+	} else if is_update {
+		upd.setup_kind = .update
+	}
+
+	if is_source {
+		upd.update_source = .git_repo
+	}
+
+	upd.pass_to_ls = fp.bool('ls', ` `, false, 'Pass the arguments to the language server.')
+	if ls_path := fp.string_opt('path', `p`, 'Path to the language server executable.') {
+		if upd.setup_kind != .none_ {
+			return error('Cannot use --install or --update when --path is supplied.')
+		} else if !os.is_executable(ls_path) {
+			return error('Provided executable is not valid.')
+		}
+
+		upd.ls_path = ls_path
+	}
+
+	upd.is_help = fp.bool('help', `h`, false, "Show this updater's help text. To show the help text for the language server, pass the `--ls` flag before it.")
+
+	if !upd.is_help && !upd.pass_to_ls {
+		// automatically set the cli launcher to language server mode
+		upd.pass_to_ls = true
+	}
+
+	if upd.pass_to_ls {
+		if upd.ls_path.len == 0 {
+			if ls_path := upd.find_ls_path() {
+				if !upd.is_force && upd.setup_kind == .install {
+					return error_with_code('VLS was already installed.', 102)
+				}
+
+				upd.ls_path = ls_path
+			} else if upd.setup_kind == .none_ {
+				return error('Language server is not installed nor found.')
+			}
+		}
+
+		if upd.is_help {
+			upd.args << '--help'
+		}
+
+		fp.allow_unknown_args()
+		upd.args << fp.finalize() or { fp.remaining_parameters() }
+	} else {
+		fp.finalize()?
+	}
+}
+
+fn (upd VlsUpdater) log(msg string) {
+	match upd.output {
+		.text {
+			println('> $msg')
+		}
+		.json {
+			print('{"message":"$msg"}')
+			flush_stdout()
+		}
+		.silent {}
+	}
+}
+
+[noreturn]
+fn (upd VlsUpdater) cli_error(err IError) {
+	match upd.output {
+		.text {
+			eprintln('v ls error: $err.msg() ($err.code())')
+			print_backtrace()
+		}
+		.json {
+			print('{"error":{"message":"$err.msg()","code":"$err.code()"}}')
+			flush_stdout()
+		}
+		.silent {}
+	}
+	exit(1)
+}
+
+fn (upd VlsUpdater) check_installation() {
+	if upd.ls_path.len == 0 {
+		upd.log('Language server is not installed')
+	} else {
+		upd.log('Language server is installed at: $upd.ls_path')
+	}
+}
+
+fn (upd VlsUpdater) run(fp flag.FlagParser) ? {
+	if upd.is_check {
+		upd.check_installation()
+	} else if upd.setup_kind != .none_ {
+		upd.check_or_create_vls_folder()?
+
+		match upd.update_source {
+			.github_releases {
+				upd.download_prebuilt() or {
+					if err.code() == 100 {
+						upd.compile_from_source()?
+					}
+					return err
+				}
+			}
+			.git_repo {
+				upd.compile_from_source()?
+			}
+		}
+	} else if upd.pass_to_ls {
+		exit(os.system('$upd.ls_path ${upd.args.join(' ')}'))
+	} else if upd.is_help {
+		println(fp.usage())
+		exit(0)
+	}
+}
+
+fn main() {
+	mut fp := flag.new_flag_parser(os.args)
+	mut upd := VlsUpdater{}
+
+	fp.application('v ls')
+	fp.description('Installs, updates, and executes the V language server program')
+	fp.version('0.1')
+	fp.skip_executable()
+
+	upd.parse(mut fp) or {
+		if err.code() == 102 {
+			upd.log(err.msg())
+			exit(0)
+		} else {
+			upd.cli_error(err)
+		}
+	}
+
+	upd.run(fp) or { upd.cli_error(err) }
+}
diff --git a/cmd/v/help/ls.txt b/cmd/v/help/ls.txt
new file mode 100644
index 000000000..84d7fedb7
--- /dev/null
+++ b/cmd/v/help/ls.txt
@@ -0,0 +1,18 @@
+Usage:
+  v ls [options] [ARGS]
+
+Description:
+  Installs, updates, and executes the V language server program
+
+Options:
+  --json                Print the output as JSON.
+  --silent              Disables output printing.
+  --install             Installs the language server. You may also use this flag to re-download or force update your existing installation.
+  --update              Updates the installed language server.
+  --check               Checks if the language server is installed.
+  --force               Force install or update the language server.
+  --source              Clone and build the language server from source.
+  --ls                  Pass the arguments to the language server.
+  -p, --path <string>   Path to the language server executable.
+  -h, --help            Show this updater's help text. To show the help text for the language server's, pass the `--ls` flag before it.
+  --version             output version information and exit
\ No newline at end of file
diff --git a/cmd/v/v.v b/cmd/v/v.v
index 5b3cfbd93..77c019b0a 100644
--- a/cmd/v/v.v
+++ b/cmd/v/v.v
@@ -28,6 +28,7 @@ const (
 		'doctor',
 		'fmt',
 		'gret',
+		'ls',
 		'missdoc',
 		'repl',
 		'self',
-- 
2.30.2