import { createRouter } from '../../create-router';
import { mkdir } from 'node:fs/promises';
import { dirname } from 'node:path';
import { getUserSettingsFile, getUserStateFile } from '@@/data-path';

const DEFAULT_SETTINGS = {
  chat: {
    defaultProvider: 'claude',
    defaultModel: null,
    systemPrompt: '',
    temperature: 1,
    defaultPwd: '~',
  },
  appearance: {
    theme: 'light',
  },
};

const ensureDir = (filePath: string) => mkdir(dirname(filePath), { recursive: true });

export const settingsRouter = createRouter();

// GET /settings — return settings.json, auto-create with defaults if missing
settingsRouter.get('/settings', async (ctx) => {
  const email = ctx.get('user').email;
  const filePath = getUserSettingsFile(email);
  const file = Bun.file(filePath);

  if (await file.exists()) {
    try {
      return ctx.json(await file.json());
    } catch {
      // corrupted — fall through to defaults
    }
  }

  await ensureDir(filePath);
  await Bun.write(file, JSON.stringify(DEFAULT_SETTINGS, null, 2));
  return ctx.json(DEFAULT_SETTINGS);
});

// PUT /settings — full replacement
settingsRouter.put('/settings', async (ctx) => {
  const email = ctx.get('user').email;
  const body = ctx.get('body');
  const filePath = getUserSettingsFile(email);

  await ensureDir(filePath);
  await Bun.write(filePath, JSON.stringify(body, null, 2));
  return ctx.json(body);
});

// GET /state — return state.json, auto-create with {} if missing
settingsRouter.get('/state', async (ctx) => {
  const email = ctx.get('user').email;
  const filePath = getUserStateFile(email);
  const file = Bun.file(filePath);

  if (await file.exists()) {
    try {
      return ctx.json(await file.json());
    } catch {
      // corrupted — fall through to empty
    }
  }

  await ensureDir(filePath);
  await Bun.write(file, JSON.stringify({}, null, 2));
  return ctx.json({});
});

// PATCH /state — shallow-merge incoming keys
settingsRouter.patch('/state', async (ctx) => {
  const email = ctx.get('user').email;
  const body = ctx.get('body');
  const filePath = getUserStateFile(email);
  const file = Bun.file(filePath);

  let existing: Record<string, unknown> = {};
  if (await file.exists()) {
    try { existing = await file.json(); } catch { /* corrupted — start fresh */ }
  }

  const merged = { ...existing, ...body };
  await ensureDir(filePath);
  await Bun.write(filePath, JSON.stringify(merged, null, 2));
  return ctx.json(merged);
});