import { existsSync, mkdirSync } from "node:fs";

import { dirname } from "node:path";

import pc from "picocolors";

import { generateCompletion, getCompletionFilePath } from "./completions.ts";

import type { Shell } from "./completions.ts";

/** Renders a hyperlink in cyan+underline when stdout is a TTY, plain otherwise. */

const upgradeLink = (url: string): string =>

process.stdout.isTTY ? pc.cyan(pc.underline(url)) : url;

// ─── Types ────────────────────────────────────────────────────────────────────

export interface ReleaseAsset {

name: string;

browser_download_url: string;

}

interface GithubRelease {

tag_name: string;

html_url: string;

assets: ReleaseAsset[];

}

// ─── Version comparison ───────────────────────────────────────────────────────

/**

* Returns true if `latest` is strictly newer than `current`.

* Both strings may be prefixed with "v" (e.g. "v1.2.3" or "1.2.3").

* When `current` is "dev" (running from source), always returns false.

*/

const parseVersion = (v: string) => v.replace(/^v/, "").split(".").map(Number);

export function isNewerVersion(current: string, latest: string): boolean {

if (current === "dev") return false;

const a = parseVersion(current);

const b = parseVersion(latest);

const len = Math.max(a.length, b.length);

for (let i = 0; i < len; i++) {

const ai = a[i] ?? 0;

const bi = b[i] ?? 0;

if (bi > ai) return true;

if (ai > bi) return false;

}

return false;

}

// ─── Asset selection ──────────────────────────────────────────────────────────

/**

* Picks the release asset matching the current platform and architecture.

* Expected asset naming convention:

* github-code-search-<platform>-<arch> (e.g. macos-arm64)

* github-code-search-<platform>-<arch>.exe (Windows)

*

* Node.js/Bun platform names are mapped to artifact names:

* darwin → macos

* win32 → windows

*

* A legacy fallback also tries the raw Node.js platform name (darwin, win32)

* so that binaries built before v1.2.1 can still upgrade themselves.

*/

export function selectAsset(

assets: ReleaseAsset[],

platform: string,

arch: string,

): ReleaseAsset | null {

const platformMap: Record<string, string> = {

darwin: "macos",

win32: "windows",

};

const artifactPlatform = platformMap[platform] ?? platform;

const suffix = artifactPlatform === "windows" ? ".exe" : "";

const name = `github-code-search-${artifactPlatform}-${arch}${suffix}`;

// Fix: fall back to legacy platform names (darwin, win32) published alongside

// the canonical names for backward-compat with pre-v1.2.1 binaries — see issue #45

const legacySuffix = platform === "win32" ? ".exe" : "";

const legacyName = `github-code-search-${platform}-${arch}${legacySuffix}`;

return assets.find((a) => a.name === name) ?? assets.find((a) => a.name === legacyName) ?? null;

}

// ─── Blog URL helper ───────────────────────────────────────────────────────────

/**

* Derives the VitePress blog post URL for a given release tag.

* Convention: vX.Y.Z → https://fulll.github.io/github-code-search/blog/release-vX-Y-Z

*/

export function blogPostUrl(tag: string): string {

// Fix: normalize to always have a v-prefix (handles both "v1.2.3" and "1.2.3")

const normalized = `v${tag.replace(/^v/, "")}`;

const slug = normalized.replace(/\./g, "-"); // v1.2.3 → v1-2-3

return `https://fulll.github.io/github-code-search/blog/release-${slug}`;

}

// ─── GitHub API ───────────────────────────────────────────────────────────────

export async function fetchLatestRelease(

token?: string,

signal?: AbortSignal,

): Promise<GithubRelease> {

const headers: Record<string, string> = {

Accept: "application/vnd.github+json",

"X-GitHub-Api-Version": "2022-11-28",

};

if (token) headers["Authorization"] = `Bearer ${token}`;

const res = await fetch("https://api.github.com/repos/fulll/github-code-search/releases/latest", {

headers,

signal,

});

if (!res.ok) {

const body = await res.text();

throw new Error(`GitHub API error ${res.status}: ${body}`);

}

return res.json() as Promise<GithubRelease>;

}

// ─── Download ─────────────────────────────────────────────────────────────────

/**

* Downloads a binary from `url` and atomically replaces `dest`.

* Uses a ".tmp" sibling file so the replacement is atomic on the same FS.

*/

async function downloadBinary(url: string, dest: string, debug = false): Promise<void> {

// Validate URL to prevent SSRF attacks — initial URL must come from github.com.

try {

const parsedUrl = new URL(url);

if (parsedUrl.hostname !== "github.com") {

throw new Error("Invalid host");

}

if (parsedUrl.protocol !== "https:") {

throw new Error("Invalid protocol");

}

} catch {

throw new Error("Invalid URL");

}

if (debug) process.stdout.write(`[debug] downloading from ${url}\n`);

// Follow redirects manually to validate each hop — prevents redirect-based SSRF.

// GitHub release assets redirect from github.com to *.githubusercontent.com, so both

// are allowed redirect targets; all other hosts are blocked.

let currentUrl = url;

let res!: Response;

const maxRedirects = 10;

for (let redirectCount = 0; ; redirectCount++) {

if (redirectCount > maxRedirects) throw new Error("Too many redirects");

res = await fetch(currentUrl, { redirect: "manual" });

if (res.status >= 300 && res.status < 400) {

const location = res.headers.get("location");

if (!location) break;

let nextUrl: URL;

try {

nextUrl = new URL(location, currentUrl);

} catch {

throw new Error("Redirect blocked: invalid Location header");

}

const h = nextUrl.hostname;

const isAllowedHost = h === "github.com" || h.endsWith(".githubusercontent.com");

if (!isAllowedHost || nextUrl.protocol !== "https:") {

throw new Error("Redirect blocked");

}

currentUrl = nextUrl.toString();

continue;

}

break;

}

if (debug)

process.stdout.write(

`[debug] fetch response: status=${res.status} ok=${res.ok} url=${currentUrl}\n`,

);

if (!res.ok) {

throw new Error(`Download failed (${res.status}): ${url}`);

}

// Fix: read the body explicitly as an ArrayBuffer rather than passing the

// Response object to Bun.write, which avoids edge-case issues with Response

// body streaming on certain Bun versions.

const buffer = await res.arrayBuffer();

if (debug) process.stdout.write(`[debug] downloaded ${buffer.byteLength} bytes\n`);

if (buffer.byteLength === 0) {

throw new Error(`Downloaded empty file from ${url}`);

}

const tmpPath = `${dest}.tmp`;

process.stdout.write(`Replacing ${dest}…\n`);

await Bun.write(tmpPath, buffer);

if (debug) process.stdout.write(`[debug] wrote tmp file ${tmpPath}\n`);

// Remove quarantine attribute if present (macOS only) so Gatekeeper

// does not block the replaced binary on the next run.

if (process.platform === "darwin") {

const xattr = Bun.spawnSync(["xattr", "-d", "com.apple.quarantine", tmpPath]);

const xattrStderr = xattr.stderr?.toString() ?? "";

if (debug) {

process.stdout.write(

`[debug] xattr exit=${xattr.exitCode} stderr=${JSON.stringify(xattrStderr)}\n`,

);

}

if (xattr.exitCode !== 0) {

// macOS xattr uses ENOATTR for "attribute does not exist"; the error

// message typically includes "No such xattr" or "No such attribute".

const lowerStderr = xattrStderr.toLowerCase();

const isNoSuchAttr =

lowerStderr.includes("no such xattr") || lowerStderr.includes("no such attribute");

if (!isNoSuchAttr) {

throw new Error(`xattr failed: ${xattrStderr}`);

}

}

}

// Make executable and atomically replace the binary

const chmod = Bun.spawnSync(["chmod", "+x", tmpPath]);

if (chmod.exitCode !== 0) {

throw new Error(`chmod failed: ${chmod.stderr.toString()}`);

}

if (debug) process.stdout.write(`[debug] chmod +x done\n`);

const mv = Bun.spawnSync(["mv", tmpPath, dest]);

if (mv.exitCode !== 0) {

throw new Error(`mv failed: ${mv.stderr.toString()}`);

}

if (debug) process.stdout.write(`[debug] mv done → ${dest}\n`);

}

// ─── Orchestration ────────────────────────────────────────────────────────────

/**

* Checks for a newer release and, if found, downloads and replaces `execPath`.

*/

export async function performUpgrade(

currentVersion: string,

execPath: string,

token?: string,

debug = false,

): Promise<void> {

if (currentVersion === "dev") {

process.stdout.write(

"Running from source (dev). Upgrade is only available for compiled binaries.\n",

);

return;

}

process.stdout.write("Checking for updates…\n");

const release = await fetchLatestRelease(token);

const latestVersion = release.tag_name;

if (!isNewerVersion(currentVersion, latestVersion)) {

process.stdout.write(

`Congrats! You're already on the latest version of github-code-search (${latestVersion}).\n`,

);

return;

}

const asset = selectAsset(release.assets, process.platform, process.arch);

if (debug) {

process.stdout.write(

`[debug] available assets: ${release.assets.map((a) => a.name).join(", ")}\n`,

);

process.stdout.write(`[debug] selected asset: ${asset?.name ?? "(none)"}\n`);

}

if (!asset) {

throw new Error(

`No binary found for platform ${process.platform}/${process.arch} in release ${latestVersion}.`,

);

}

process.stdout.write(`Upgrading ${currentVersion} → ${latestVersion}…\n`);

await downloadBinary(asset.browser_download_url, execPath, debug);

process.stdout.write(

[

``,

`Welcome to github-code-search ${latestVersion}!`,

``,

`What's new in ${latestVersion}:`,

` ${upgradeLink(blogPostUrl(latestVersion))}`,

``,

`Release notes:`,

` ${upgradeLink(release.html_url)}`,

``,

`Commit log:`,

` ${upgradeLink(`https://github.com/fulll/github-code-search/compare/${currentVersion.startsWith("v") ? currentVersion : `v${currentVersion}`}...${latestVersion}`)}`,

``,

`Report a bug:`,

` ${upgradeLink("https://github.com/fulll/github-code-search/issues/new")}`,

``,

`Run \`github-code-search --help\` to explore all options.`,

``,

].join("\n"),

);

}

// ─── Silent update check ──────────────────────────────────────────────────────

/**

* Returns the latest version tag if it is strictly newer than `currentVersion`, or null.

* Silently swallows any network / API error so it never breaks the main search flow.

*/

export async function checkForUpdate(

currentVersion: string,

token?: string,

signal?: AbortSignal,

): Promise<string | null> {

if (currentVersion === "dev") return null;

try {

const release = await fetchLatestRelease(token, signal);

return isNewerVersion(currentVersion, release.tag_name) ? release.tag_name : null;

} catch {

return null;

}

}

// ─── Completion refresh ────────────────────────────────────────────────────────

/**

* Installs or refreshes the shell completion file.

* Always writes the file (creates it if absent, overwrites it if present).

* Returns the written file path, or null when `shell` is null.

*/

export async function refreshCompletions(

shell: Shell | null,

homeDir?: string,

debug = false,

): Promise<string | null> {

if (!shell) return null;

const opts = homeDir ? { homeDir } : {};

const filePath = getCompletionFilePath(shell, opts);

const alreadyExists = existsSync(filePath);

if (debug) {

process.stdout.write(

alreadyExists

? `[debug] refreshing completions at ${filePath}\n`

: `[debug] installing completions at ${filePath}\n`,

);

}

const script = generateCompletion(shell);

mkdirSync(dirname(filePath), { recursive: true });

await Bun.write(filePath, script);

if (debug) process.stdout.write(`[debug] completions written at ${filePath}\n`);

return filePath;

}