import fs from 'fs';
import os from 'os';
import path from 'path';
import { afterEach, describe, expect, it, vi } from 'vitest';
import { createMessageQueueRuntime, parseQueuedItemInput } from './runtime.js';

const SESSION = 'ses_queue_test_1';
const DIRECTORY = '/repo';

const item = (overrides = {}) => ({
  content: 'follow up',
  text: 'follow up',
  attachments: [],
  sendConfig: { providerID: 'anthropic', modelID: 'claude', agent: 'build' },
  ...overrides,
});

const tempDirs = [];
const makeDataDir = () => {
  const dir = fs.mkdtempSync(path.join(os.tmpdir(), 'openchamber-message-queue-'));
  tempDirs.push(dir);
  return dir;
};

afterEach(() => {
  vi.useRealTimers();
  for (const dir of tempDirs.splice(0)) fs.rmSync(dir, { recursive: true, force: true });
});

/**
 * A fake OpenCode: status map, message tail, command list, and a log of every
 * prompt/command it received.
 */
const createOpenCode = () => {
  const state = {
    statuses: {},
    tail: [],
    commands: [],
    sent: [],
    failNext: null,
  };
  const fetchImpl = vi.fn(async (url, init = {}) => {
    const { pathname } = new URL(url);
    const method = init.method ?? 'GET';
    if (state.failNext && state.failNext.test(pathname)) {
      state.failNext = null;
      return new Response('boom', { status: 500 });
    }
    if (pathname === '/session/status') return Response.json(state.statuses);
    if (pathname.endsWith('/message')) return Response.json(state.tail);
    if (pathname === '/command') return Response.json(state.commands);
    if (method === 'POST' && (pathname.endsWith('/prompt_async') || pathname.endsWith('/command'))) {
      state.sent.push({ path: pathname, body: JSON.parse(init.body) });
      return new Response(null, { status: 204 });
    }
    return new Response('not found', { status: 404 });
  });
  return { state, fetchImpl };
};

const createRuntime = ({ dataDir = makeDataDir(), openCode = createOpenCode(), knowledge = null, retryDelayMs } = {}) => {
  let eventHandler = () => {};
  let statusHandler = () => {};
  const broadcasts = [];
  const promptSent = [];
  const options = {
    globalEventHub: {
      subscribeEvent(handler) { eventHandler = handler; return () => {}; },
      subscribeStatus(handler) { statusHandler = handler; return () => {}; },
    },
    buildOpenCodeUrl: (fetchPath) => `http://opencode.test${fetchPath}`,
    getOpenCodeAuthHeaders: () => ({}),
    sessionKnowledgeRuntime: knowledge,
    broadcastGlobalUiEvent: (event) => broadcasts.push(event),
    onPromptSent: (sessionId) => promptSent.push(sessionId),
    dataDir,
    fetchImpl: openCode.fetchImpl,
    dispatchQuietMs: 0,
    abortHoldMs: 50,
  };
  if (retryDelayMs) options.retryDelayMs = retryDelayMs;
  const runtime = createMessageQueueRuntime(options);
  return {
    runtime,
    openCode,
    dataDir,
    broadcasts,
    promptSent,
    emit: (payload, directory = DIRECTORY) => eventHandler({ payload, directory }),
    connect: () => statusHandler({ type: 'connect' }),
  };
};

const settle = async (ms = 30) => {
  await new Promise((resolve) => setTimeout(resolve, ms));
};

describe('parseQueuedItemInput', () => {
  it('rejects an item the server could not deliver later', () => {
    expect(() => parseQueuedItemInput({ content: 'x' })).toThrow(TypeError);
    expect(() => parseQueuedItemInput(item({ content: '', text: '' }))).toThrow(TypeError);
    expect(() => parseQueuedItemInput(item({ attachments: [{ filename: 'a.png' }] }))).toThrow(TypeError);
  });

  it('keeps delivery fields and trims blank edges of the content', () => {
    const parsed = parseQueuedItemInput(item({ content: '\n\nhello\n', text: 'hello', agentMention: 'reviewer' }));
    expect(parsed).toEqual({
      content: 'hello',
      text: 'hello',
      agentMention: 'reviewer',
      attachments: [],
      context: [],
      sendConfig: { providerID: 'anthropic', modelID: 'claude', agent: 'build' },
    });
  });

  it('keeps captured context and rejects a malformed part', () => {
    const context = [
      { kind: 'context', text: 'Comment on `a.ts`', metadata: { openchamberContext: { kind: 'code-comment' } }, instructions: '' },
      { kind: 'instruction', text: 'use the skill' },
      { kind: 'synthetic', text: 'conflict payload' },
    ];
    expect(parseQueuedItemInput(item({ context })).context).toEqual([
      { kind: 'context', text: 'Comment on `a.ts`', metadata: { openchamberContext: { kind: 'code-comment' } } },
      { kind: 'instruction', text: 'use the skill' },
      { kind: 'synthetic', text: 'conflict payload' },
    ]);
    expect(() => parseQueuedItemInput(item({ context: [{ kind: 'context', text: 'no metadata' }] }))).toThrow(TypeError);
    expect(() => parseQueuedItemInput(item({ context: [{ kind: 'other', text: 'x' }] }))).toThrow(TypeError);
  });

  it('accepts an item that is only context', () => {
    const parsed = parseQueuedItemInput(item({ content: '', text: '', context: [{ kind: 'synthetic', text: 'just context' }] }));
    expect(parsed.text).toBe('');
    expect(parsed.context).toHaveLength(1);
  });
});

describe('message queue runtime', () => {
  it('delivers the head of the queue when the session goes idle, in order', async () => {
    const { runtime, openCode, emit, promptSent, broadcasts } = createRuntime();
    runtime.start();
    openCode.state.statuses = { [SESSION]: { type: 'busy' } };

    await runtime.enqueue(SESSION, DIRECTORY, item({ content: 'first', text: 'first' }));
    await runtime.enqueue(SESSION, DIRECTORY, item({ content: 'second', text: 'second' }));
    await settle();
    expect(openCode.state.sent).toHaveLength(0);

    openCode.state.statuses = {};
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();

    expect(openCode.state.sent).toHaveLength(1);
    expect(openCode.state.sent[0].path).toBe(`/session/${SESSION}/prompt_async`);
    expect(openCode.state.sent[0].body).toEqual({
      model: { providerID: 'anthropic', modelID: 'claude' },
      agent: 'build',
      parts: [{ type: 'text', text: 'first' }],
    });
    expect(promptSent).toEqual([SESSION]);
    expect(runtime.sessionSnapshot(SESSION).items.map((entry) => entry.content)).toEqual(['second']);
    // Clients learned about the in-flight item and then the removal.
    expect(broadcasts.at(-1)).toMatchObject({
      type: 'openchamber:message-queue.updated',
      properties: { session: { sessionId: SESSION, sendingId: null } },
    });

    // The next turn: busy, then idle again — the second message goes out.
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'busy' } } });
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent).toHaveLength(2);
    expect(runtime.sessionSnapshot(SESSION).items).toEqual([]);
  });

  it('does not send into a running turn even when the status event says idle', async () => {
    const { runtime, openCode, emit } = createRuntime();
    runtime.start();
    openCode.state.tail = [{ info: { role: 'assistant', time: { created: 1 } } }];
    await runtime.enqueue(SESSION, DIRECTORY, item());
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent).toHaveLength(0);

    // The reply completes: that alone drains the queue (a missed idle event
    // must not strand it).
    openCode.state.tail = [{ info: { role: 'assistant', time: { created: 1, completed: 2 } } }];
    emit({ type: 'message.updated', properties: { info: { role: 'assistant', sessionID: SESSION, time: { created: 1, completed: 2 } } } });
    await settle();
    expect(openCode.state.sent).toHaveLength(1);
  });

  it('treats an unreachable OpenCode as unknown, not idle', async () => {
    const { runtime, openCode, emit } = createRuntime({ retryDelayMs: () => 10 });
    runtime.start();
    await runtime.enqueue(SESSION, DIRECTORY, item());
    openCode.state.failNext = /\/session\/status$/;
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle(5);
    expect(openCode.state.sent).toHaveLength(0);
    // Retried after the status fetch recovers.
    await settle(40);
    expect(openCode.state.sent).toHaveLength(1);
  });

  it('keeps a failed item and retries with backoff', async () => {
    const { runtime, openCode, emit, broadcasts } = createRuntime({ retryDelayMs: () => 20 });
    runtime.start();
    await runtime.enqueue(SESSION, DIRECTORY, item());
    openCode.state.failNext = /prompt_async$/;
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle(10);
    expect(openCode.state.sent).toHaveLength(0);
    expect(runtime.sessionSnapshot(SESSION).items).toHaveLength(1);
    expect(runtime.sessionSnapshot(SESSION).sendingId).toBeNull();
    expect(broadcasts.at(-1).properties.session.sendingId).toBeNull();
    await settle(40);
    expect(openCode.state.sent).toHaveLength(1);
    expect(runtime.sessionSnapshot(SESSION).items).toHaveLength(0);
  });

  it('holds delivery briefly after a user abort', async () => {
    const { runtime, openCode, emit } = createRuntime();
    runtime.start();
    await runtime.enqueue(SESSION, DIRECTORY, item());
    emit({ type: 'message.updated', properties: { info: { role: 'assistant', sessionID: SESSION, error: { name: 'MessageAbortedError' } } } });
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle(10);
    expect(openCode.state.sent).toHaveLength(0);
    await settle(80);
    expect(openCode.state.sent).toHaveLength(1);
  });

  it('honors a hold until it is released', async () => {
    const { runtime, openCode, emit } = createRuntime();
    runtime.start();
    await runtime.enqueue(SESSION, DIRECTORY, item());
    runtime.setHold(SESSION, true, 60_000);
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent).toHaveLength(0);

    runtime.setHold(SESSION, false);
    await settle();
    expect(openCode.state.sent).toHaveLength(1);
  });

  it('survives a restart and delivers once OpenCode reconnects', async () => {
    const dataDir = makeDataDir();
    const first = createRuntime({ dataDir });
    first.runtime.start();
    first.openCode.state.statuses = { [SESSION]: { type: 'busy' } };
    await first.runtime.enqueue(SESSION, DIRECTORY, item({ content: 'persisted', text: 'persisted' }));
    await first.runtime.flush();
    first.runtime.stop();

    const second = createRuntime({ dataDir });
    second.runtime.start();
    await second.runtime.load();
    expect(second.runtime.sessionSnapshot(SESSION).items.map((entry) => entry.content)).toEqual(['persisted']);
    second.connect();
    await settle();
    expect(second.openCode.state.sent).toHaveLength(1);
    expect(second.openCode.state.sent[0].body.parts).toEqual([{ type: 'text', text: 'persisted' }]);
  });

  it('moves an unreadable queue file aside instead of treating it as empty', async () => {
    const dataDir = makeDataDir();
    fs.writeFileSync(path.join(dataDir, 'message-queue.json'), '{ not json');
    const { runtime } = createRuntime({ dataDir });
    await runtime.load();
    expect(runtime.snapshot().sessions).toEqual([]);
    expect(fs.readdirSync(dataDir).some((name) => name.startsWith('message-queue.json.corrupt-'))).toBe(true);
  });

  it('refuses to remove or take the item currently being sent', async () => {
    const { runtime, openCode, emit } = createRuntime();
    runtime.start();
    let release;
    // status map, message tail, then the prompt itself (held open until released)
    openCode.fetchImpl.mockImplementationOnce(async () => Response.json({}))
      .mockImplementationOnce(async () => Response.json([]))
      .mockImplementationOnce(() => new Promise((resolve) => { release = () => resolve(new Response(null, { status: 204 })); }));
    const { itemId } = await runtime.enqueue(SESSION, DIRECTORY, item());
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(runtime.sessionSnapshot(SESSION).sendingId).toBe(itemId);

    await expect(runtime.remove(SESSION, itemId)).rejects.toMatchObject({ status: 409 });
    await expect(runtime.take(SESSION, itemId)).rejects.toMatchObject({ status: 409 });
    const taken = await runtime.takeAll(SESSION);
    expect(taken.items).toEqual([]);
    expect(runtime.sessionSnapshot(SESSION).items).toHaveLength(1);

    release();
    await settle();
    expect(runtime.sessionSnapshot(SESSION).items).toHaveLength(0);
  });

  it('take hands back the full payload and leaves the rest queued', async () => {
    const { runtime } = createRuntime();
    runtime.start();
    const attachment = { id: 'a1', filename: 'shot.png', mimeType: 'image/png', size: 3, source: 'local', dataUrl: 'data:image/png;base64,AAA=' };
    const first = await runtime.enqueue(SESSION, DIRECTORY, item({ content: 'with image', attachments: [attachment] }));
    await runtime.enqueue(SESSION, DIRECTORY, item({ content: 'plain' }));

    expect(runtime.sessionSnapshot(SESSION).items[0].attachments[0]).not.toHaveProperty('dataUrl');
    const taken = await runtime.take(SESSION, first.itemId);
    expect(taken.item.attachments[0].dataUrl).toBe(attachment.dataUrl);
    expect(runtime.sessionSnapshot(SESSION).items.map((entry) => entry.content)).toEqual(['plain']);

    const all = await runtime.takeAll(SESSION);
    expect(all.items.map((entry) => entry.content)).toEqual(['plain']);
    expect(runtime.snapshot().sessions).toEqual([]);
  });

  it('names the directory in the broadcast that empties a queue', async () => {
    // The UI keys its projection by directory; without it the client cannot
    // tell which queue just delivered its last message and keeps showing it.
    const { runtime, emit, broadcasts, openCode } = createRuntime();
    runtime.start();
    await runtime.enqueue(SESSION, DIRECTORY, item());
    openCode.state.statuses = {};
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();

    expect(openCode.state.sent).toHaveLength(1);
    expect(runtime.snapshot().sessions).toEqual([]);
    expect(broadcasts.at(-1).properties.session).toEqual({ sessionId: SESSION, directory: DIRECTORY, items: [], sendingId: null });
  });

  it('reorders only with a complete permutation', async () => {
    const { runtime } = createRuntime();
    runtime.start();
    const a = await runtime.enqueue(SESSION, DIRECTORY, item({ content: 'a' }));
    const b = await runtime.enqueue(SESSION, DIRECTORY, item({ content: 'b' }));
    await expect(runtime.reorder(SESSION, [b.itemId])).rejects.toThrow(TypeError);
    await runtime.reorder(SESSION, [b.itemId, a.itemId]);
    expect(runtime.sessionSnapshot(SESSION).items.map((entry) => entry.content)).toEqual(['b', 'a']);
  });

  it('drops the queue of a deleted session', async () => {
    const { runtime, emit, broadcasts } = createRuntime();
    runtime.start();
    await runtime.enqueue(SESSION, DIRECTORY, item());
    emit({ type: 'session.deleted', properties: { info: { id: SESSION } } });
    expect(runtime.snapshot().sessions).toEqual([]);
    expect(broadcasts.at(-1).properties.session).toMatchObject({ sessionId: SESSION, items: [] });
  });

  it('dispatches a queued slash command through the command endpoint', async () => {
    const { runtime, openCode, emit } = createRuntime();
    runtime.start();
    openCode.state.commands = [{ name: 'review' }];
    await runtime.enqueue(SESSION, DIRECTORY, item({ content: '/review src', text: '/review src', sendConfig: { providerID: 'p', modelID: 'm', agent: 'build', variant: 'max' } }));
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent).toHaveLength(1);
    expect(openCode.state.sent[0].path).toBe(`/session/${SESSION}/command`);
    expect(openCode.state.sent[0].body).toEqual({ command: 'review', arguments: 'src', model: 'p/m', agent: 'build', variant: 'max' });
  });

  it('delivers captured context as synthetic parts, instructions first, before project knowledge', async () => {
    const knowledge = {
      resolvePendingForSession: async () => ({ text: 'pinned notes', signature: 'sig-1' }),
      recordDelivered: async () => {},
    };
    const { runtime, openCode, emit } = createRuntime({ knowledge });
    runtime.start();
    const metadata = { openchamberContext: { kind: 'github-pr', number: 7, title: 'PR', url: 'https://x/pr/7' } };
    await runtime.enqueue(SESSION, DIRECTORY, item({
      agentMention: 'reviewer',
      attachments: [{ id: 'a', filename: 'f.txt', mimeType: 'text/plain', size: 1, source: 'local', dataUrl: 'data:text/plain,hi' }],
      context: [
        { kind: 'context', text: 'the diff', metadata, instructions: 'how to read it' },
        { kind: 'synthetic', text: 'conflict payload' },
        { kind: 'instruction', text: 'use the skill' },
      ],
    }));
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent[0].body.parts).toEqual([
      { type: 'text', text: 'follow up' },
      { type: 'file', mime: 'text/plain', filename: 'f.txt', url: 'data:text/plain,hi' },
      { type: 'text', text: 'how to read it', synthetic: true },
      { type: 'text', text: 'the diff', synthetic: true, metadata },
      { type: 'text', text: 'conflict payload', synthetic: true },
      { type: 'text', text: 'use the skill', synthetic: true },
      { type: 'text', text: 'pinned notes', synthetic: true },
      { type: 'agent', name: 'reviewer' },
    ]);
  });

  it('keeps files on the command route, which is all that route accepts', async () => {
    const { runtime, openCode, emit } = createRuntime();
    runtime.start();
    openCode.state.commands = [{ name: 'review' }];
    await runtime.enqueue(SESSION, DIRECTORY, item({
      content: '/review',
      text: '/review',
      attachments: [{ id: 'a', filename: 'f.txt', mimeType: 'text/plain', size: 1, source: 'local', dataUrl: 'data:text/plain,hi' }],
    }));
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent[0].path).toBe(`/session/${SESSION}/command`);
    expect(openCode.state.sent[0].body.parts).toEqual([{ type: 'file', mime: 'text/plain', filename: 'f.txt', url: 'data:text/plain,hi' }]);
  });

  it('sends a command queued with context as its expanded prompt, context included', async () => {
    // The command route rejects text parts, so a command with captured
    // context takes the prompt route with the template expanded, exactly as
    // the composer does.
    const { runtime, openCode, emit } = createRuntime();
    runtime.start();
    openCode.state.commands = [{ name: 'review', source: 'command', template: 'Review $1 with focus on $2' }];
    const metadata = { openchamberContext: { kind: 'chat-quote', quote: 'q', text: 'why?' } };
    await runtime.enqueue(SESSION, DIRECTORY, item({
      content: '/review src "error handling"',
      text: '/review src "error handling"',
      context: [{ kind: 'context', text: 'quoted', metadata }],
    }));
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent[0].path).toBe(`/session/${SESSION}/prompt_async`);
    expect(openCode.state.sent[0].body.parts).toEqual([
      { type: 'text', text: 'Review src with focus on error handling' },
      { type: 'text', text: 'quoted', synthetic: true, metadata },
    ]);
  });

  it('sends a skill queued with context as an explicit invocation, context included', async () => {
    const { runtime, openCode, emit } = createRuntime();
    runtime.start();
    openCode.state.commands = [{ name: 'grill', source: 'skill', template: 'skill body' }];
    await runtime.enqueue(SESSION, DIRECTORY, item({
      content: '/grill auth',
      text: '/grill auth',
      context: [{ kind: 'synthetic', text: 'focus on tests' }],
    }));
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent[0].path).toBe(`/session/${SESSION}/prompt_async`);
    expect(openCode.state.sent[0].body.parts).toEqual([
      { type: 'text', text: '/grill auth' },
      { type: 'text', text: 'focus on tests', synthetic: true },
      { type: 'text', text: 'The user explicitly invoked the grill skill. Use the corresponding skill tool to handle this request.', synthetic: true },
    ]);
  });

  it('keeps captured context out of snapshots and broadcasts, and hands it back on take', async () => {
    const { runtime, broadcasts } = createRuntime();
    runtime.start();
    const context = [{ kind: 'synthetic', text: 'a large diff' }];
    const { itemId } = await runtime.enqueue(SESSION, DIRECTORY, item({ context }));
    expect(runtime.sessionSnapshot(SESSION).items[0]).not.toHaveProperty('context');
    expect(runtime.sessionSnapshot(SESSION).items[0].text).toBe('follow up');
    expect(broadcasts.at(-1).properties.session.items[0]).not.toHaveProperty('context');
    const taken = await runtime.take(SESSION, itemId);
    expect(taken.item.context).toEqual(context);
  });

  it('attaches pending project knowledge and records its delivery', async () => {
    const recorded = [];
    const knowledge = {
      resolvePendingForSession: async () => ({ text: 'pinned notes', signature: 'sig-1' }),
      recordDelivered: async (sessionId, directory, signature) => { recorded.push({ sessionId, directory, signature }); },
    };
    const { runtime, openCode, emit } = createRuntime({ knowledge });
    runtime.start();
    await runtime.enqueue(SESSION, DIRECTORY, item({ agentMention: 'reviewer', attachments: [{ id: 'a', filename: 'f.txt', mimeType: 'text/plain', size: 1, source: 'local', dataUrl: 'data:text/plain,hi' }] }));
    emit({ type: 'session.status', properties: { sessionID: SESSION, status: { type: 'idle' } } });
    await settle();
    expect(openCode.state.sent[0].body.parts).toEqual([
      { type: 'text', text: 'follow up' },
      { type: 'file', mime: 'text/plain', filename: 'f.txt', url: 'data:text/plain,hi' },
      { type: 'text', text: 'pinned notes', synthetic: true },
      { type: 'agent', name: 'reviewer' },
    ]);
    expect(recorded).toEqual([{ sessionId: SESSION, directory: DIRECTORY, signature: 'sig-1' }]);
  });
});