/**
 * uat/cli/lib/app-config.ts — Resolve the generated app's runtime endpoints and the
 * initial admin credentials from its own config files (no live process needed).
 *
 *   API URL      ← spec override → Properties/launchSettings.json (first profile's
 *                  applicationUrl, http preferred) → http://localhost:5142
 *   Frontend URL ← spec override → vite.config.* `port:` → http://localhost:5173
 *   Initial admin← spec override → Security.InitialAdmin in appsettings.Local.json
 *                  → appsettings.Development.json → appsettings.json (same cascade
 *                  as the DB connection; `ss dev configure` writes Local).
 *
 * Every resolver reports its source so envelopes can say where a value came from.
 */
import { existsSync, readFileSync } from 'node:fs';
import { join } from 'node:path';

export interface Resolved<T> {
  value: T;
  /** Where the value came from (file name, 'spec', or 'default'). */
  source: string;
}

function readJsonSafe(filePath: string): Record<string, unknown> | null {
  try {
    if (!existsSync(filePath)) return null;
    return JSON.parse(readFileSync(filePath, 'utf-8')) as Record<string, unknown>;
  } catch {
    return null;
  }
}

const stripTrailingSlash = (url: string): string => url.replace(/\/+$/, '');

/** Pick the http:// URL out of a launchSettings `applicationUrl` (";"-separated). PURE. */
export function pickHttpUrl(applicationUrl: string): string | null {
  const urls = applicationUrl
    .split(';')
    .map((u) => u.trim())
    .filter(Boolean);
  return urls.find((u) => u.startsWith('http://')) ?? urls[0] ?? null;
}

/** Extract the first profile applicationUrl from a parsed launchSettings.json. PURE. */
export function apiUrlFromLaunchSettings(json: Record<string, unknown>): string | null {
  const profiles = json.profiles;
  if (!profiles || typeof profiles !== 'object') return null;
  for (const profile of Object.values(profiles as Record<string, unknown>)) {
    if (!profile || typeof profile !== 'object') continue;
    const appUrl = (profile as Record<string, unknown>).applicationUrl;
    if (typeof appUrl === 'string' && appUrl.length > 0) {
      const picked = pickHttpUrl(appUrl);
      if (picked) return stripTrailingSlash(picked);
    }
  }
  return null;
}

export function resolveApiUrl(apiDir: string, override?: string): Resolved<string> {
  if (override) return { value: stripTrailingSlash(override), source: 'spec' };
  const json = readJsonSafe(join(apiDir, 'Properties', 'launchSettings.json'));
  if (json) {
    const url = apiUrlFromLaunchSettings(json);
    if (url) return { value: url, source: 'Properties/launchSettings.json' };
  }
  return { value: 'http://localhost:5142', source: 'default' };
}

/** Extract a `port: NNNN` from a vite config source. PURE. */
export function portFromViteConfig(content: string): number | null {
  const m = /\bport\s*:\s*(\d{2,5})/.exec(content);
  return m ? Number(m[1]) : null;
}

export function resolveFrontendUrl(webDir: string, override?: string): Resolved<string> {
  if (override) return { value: stripTrailingSlash(override), source: 'spec' };
  for (const name of ['vite.config.ts', 'vite.config.mts', 'vite.config.js']) {
    const file = join(webDir, name);
    if (!existsSync(file)) continue;
    try {
      const port = portFromViteConfig(readFileSync(file, 'utf-8'));
      if (port) return { value: `http://localhost:${port}`, source: name };
    } catch {
      /* unreadable config falls through to the default */
    }
  }
  return { value: 'http://localhost:5173', source: 'default' };
}

export interface InitialAdmin {
  email: string;
  password: string | null;
}

/** Default seeded admin email when none is configured (SmartStack.app UserSeedData). */
export const DEFAULT_ADMIN_EMAIL = 'local.admin@smartstack.local';

export function resolveInitialAdmin(
  apiDir: string,
  overrides: { email?: string; password?: string } = {},
): Resolved<InitialAdmin> {
  if (overrides.email && overrides.password) {
    return { value: { email: overrides.email, password: overrides.password }, source: 'spec' };
  }
  let email = overrides.email ?? null;
  let password = overrides.password ?? null;
  let source = overrides.email || overrides.password ? 'spec+' : '';
  for (const file of ['appsettings.Local.json', 'appsettings.Development.json', 'appsettings.json']) {
    if (email && password) break;
    const json = readJsonSafe(join(apiDir, file));
    const admin = (json?.Security as Record<string, unknown> | undefined)?.InitialAdmin as
      | Record<string, unknown>
      | undefined;
    if (!admin) continue;
    if (!email && typeof admin.Email === 'string' && admin.Email.length > 0) email = admin.Email;
    if (!password && typeof admin.Password === 'string' && admin.Password.length > 0) {
      password = admin.Password;
      source += file;
    }
  }
  return {
    value: { email: email ?? DEFAULT_ADMIN_EMAIL, password },
    source: source || 'default',
  };
}