chore: add project management metadata and remaining repository files

launcher/log.ts

@@ -0,0 +1,59 @@
+import fs from 'node:fs';
+import path from 'node:path';
+import type { LogLevel } from './types.js';
+import { DEFAULT_MPV_LOG_FILE } from './types.js';
+
+export const COLORS = {
+  red: '\x1b[0;31m',
+  green: '\x1b[0;32m',
+  yellow: '\x1b[0;33m',
+  cyan: '\x1b[0;36m',
+  reset: '\x1b[0m',
+};
+
+export const LOG_PRI: Record<LogLevel, number> = {
+  debug: 10,
+  info: 20,
+  warn: 30,
+  error: 40,
+};
+
+export function shouldLog(level: LogLevel, configured: LogLevel): boolean {
+  return LOG_PRI[level] >= LOG_PRI[configured];
+}
+
+export function getMpvLogPath(): string {
+  const envPath = process.env.SUBMINER_MPV_LOG?.trim();
+  if (envPath) return envPath;
+  return DEFAULT_MPV_LOG_FILE;
+}
+
+export function appendToMpvLog(message: string): void {
+  const logPath = getMpvLogPath();
+  try {
+    fs.mkdirSync(path.dirname(logPath), { recursive: true });
+    fs.appendFileSync(logPath, `[${new Date().toISOString()}] ${message}\n`, { encoding: 'utf8' });
+  } catch {
+    // ignore logging failures
+  }
+}
+
+export function log(level: LogLevel, configured: LogLevel, message: string): void {
+  if (!shouldLog(level, configured)) return;
+  const color =
+    level === 'info'
+      ? COLORS.green
+      : level === 'warn'
+        ? COLORS.yellow
+        : level === 'error'
+          ? COLORS.red
+          : COLORS.cyan;
+  process.stdout.write(`${color}[${level.toUpperCase()}]${COLORS.reset} ${message}\n`);
+  appendToMpvLog(`[${level.toUpperCase()}] ${message}`);
+}
+
+export function fail(message: string): never {
+  process.stderr.write(`${COLORS.red}[ERROR]${COLORS.reset} ${message}\n`);
+  appendToMpvLog(`[ERROR] ${message}`);
+  process.exit(1);
+}