import { createServer, request as httpRequest } from 'node:http';
import { mkdtemp, rm } from 'node:fs/promises';
import { tmpdir } from 'node:os';
import path from 'node:path';
import { afterEach, describe, expect, it } from 'vitest';
import { handleCodingAttachmentRoutes } from '../../electron/api/routes/coding-attachments';
import { CodingAttachmentStore } from '../../electron/coding-projects/attachment-store';
import type { HostApiContext } from '../../electron/api/context';

const roots: string[] = [];

afterEach(async () => {
  await Promise.all(roots.splice(0).map((root) => rm(root, { recursive: true, force: true })));
});

async function startAttachmentServer(maxBytes = 16 * 1024 * 1024) {
  const root = await mkdtemp(path.join(tmpdir(), 'makelore-coding-attachments-'));
  roots.push(root);
  const attachments = new CodingAttachmentStore(root, {
    createId: () => 'attachment-1',
    maxBytes,
  });
  const context = { codingProducts: { attachments } } as unknown as HostApiContext;
  const server = createServer((request, response) => {
    const url = new URL(request.url ?? '/', 'http://127.0.0.1');
    void handleCodingAttachmentRoutes(request, response, url, context).then((handled) => {
      if (!handled) {
        response.statusCode = 404;
        response.end();
      }
    });
  });
  await new Promise<void>((resolve) => server.listen(0, '127.0.0.1', resolve));
  const address = server.address();
  if (!address || typeof address === 'string') throw new Error('Attachment test server failed');
  return {
    baseUrl: `http://127.0.0.1:${address.port}`,
    close: async () => await new Promise<void>((resolve, reject) => {
      server.close((error) => error ? reject(error) : resolve());
    }),
  };
}

async function postDeclaredLength(
  url: string,
  contentLength: number,
): Promise<{ status: number; body: Record<string, unknown> }> {
  return await new Promise((resolve, reject) => {
    const request = httpRequest(url, {
      method: 'POST',
      headers: {
        'Content-Type': 'image/png',
        'Content-Length': String(contentLength),
      },
    }, (response) => {
      const chunks: Buffer[] = [];
      response.on('data', (chunk) => chunks.push(Buffer.from(chunk)));
      response.on('end', () => resolve({
        status: response.statusCode ?? 0,
        body: JSON.parse(Buffer.concat(chunks).toString('utf8')) as Record<string, unknown>,
      }));
    });
    request.on('error', reject);
    request.end();
  });
}

describe('coding attachment routes', () => {
  it('round-trips bounded image bytes through attachment ids', async () => {
    const server = await startAttachmentServer();
    try {
      const bytes = new Uint8Array([137, 80, 78, 71, 1, 2, 3]);
      const upload = await fetch(`${server.baseUrl}/api/coding/attachments`, {
        method: 'POST',
        headers: { 'Content-Type': 'image/png' },
        body: bytes,
      });
      expect(upload.status).toBe(201);
      await expect(upload.json()).resolves.toEqual({
        attachmentId: 'attachment-1',
        mime: 'image/png',
        byteLength: bytes.byteLength,
      });

      const preview = await fetch(
        `${server.baseUrl}/api/coding/attachments/attachment-1/content`,
      );
      expect(preview.status).toBe(200);
      expect(preview.headers.get('content-type')).toBe('image/png');
      expect(preview.headers.get('cache-control')).toBe('private, no-store');
      expect(Array.from(new Uint8Array(await preview.arrayBuffer()))).toEqual(Array.from(bytes));
    } finally {
      await server.close();
    }
  });

  it('rejects unsupported media before writing and maps missing content to 404', async () => {
    const server = await startAttachmentServer();
    try {
      const upload = await fetch(`${server.baseUrl}/api/coding/attachments`, {
        method: 'POST',
        headers: { 'Content-Type': 'text/plain' },
        body: 'not an image',
      });
      expect(upload.status).toBe(400);
      await expect(upload.json()).resolves.toMatchObject({
        code: 'CODING_ATTACHMENT_INVALID',
      });

      const missing = await fetch(
        `${server.baseUrl}/api/coding/attachments/missing/content`,
      );
      expect(missing.status).toBe(404);
      await expect(missing.json()).resolves.toMatchObject({
        code: 'CODING_ATTACHMENT_NOT_FOUND',
      });
    } finally {
      await server.close();
    }
  });

  it('rejects a declared body larger than the route limit', async () => {
    const server = await startAttachmentServer();
    try {
      const response = await postDeclaredLength(
        `${server.baseUrl}/api/coding/attachments`,
        16 * 1024 * 1024 + 1,
      );
      expect(response.status).toBe(413);
      expect(response.body).toMatchObject({
        code: 'CODING_ATTACHMENT_TOO_LARGE',
      });
    } finally {
      await server.close();
    }
  });
});