import type { AgentProject } from '@prisma/client';
import { describe, it, expect, vi, beforeEach } from 'vitest';

import type { IAgentProjectRepository } from '../../src/repositories/agent-project.repository.js';
import { AgentProjectService } from '../../src/services/agent-project.service.js';
import type { AgentService } from '../../src/services/agent.service.js';
import type { LlmService } from '../../src/services/llm.service.js';
import { NotFoundError } from '../../src/services/mcp-server.service.js';
import type { ProjectService } from '../../src/services/project.service.js';

const NOW = new Date('2026-01-01T00:00:00Z');

/**
 * In-memory AgentProject junction. The unique (agentId, projectId) constraint
 * is modelled here because the service's idempotent re-join depends on it —
 * without it the "join twice" test would pass for the wrong reason.
 */
function makeHarness(seed: Array<Partial<AgentProject>> = []) {
  let idCounter = 1;
  let rows: AgentProject[] = seed.map((r) => ({
    id: r.id ?? `ap-${String(idCounter++)}`,
    agentId: r.agentId ?? 'agent-alice',
    projectId: r.projectId ?? 'proj-sre',
    role: r.role ?? 'developer',
    llmId: r.llmId ?? null,
    createdAt: NOW,
  }) as AgentProject);

  const repo = {
    findByAgent: vi.fn(async (agentId: string) => rows.filter((r) => r.agentId === agentId)),
    findByProject: vi.fn(async (projectId: string) => rows.filter((r) => r.projectId === projectId)),
    find: vi.fn(async (agentId: string, projectId: string) =>
      rows.find((r) => r.agentId === agentId && r.projectId === projectId) ?? null,
    ),
    create: vi.fn(async (data: { agentId: string; projectId: string; role?: string; llmId?: string | null }) => {
      const row = {
        id: `ap-${String(idCounter++)}`,
        agentId: data.agentId,
        projectId: data.projectId,
        role: data.role ?? 'developer',
        llmId: data.llmId ?? null,
        createdAt: NOW,
      } as AgentProject;
      rows = [...rows, row];
      return row;
    }),
    update: vi.fn(async (id: string, data: { role?: string; llmId?: string | null }) => {
      const row = rows.find((r) => r.id === id);
      if (row === undefined) throw new Error(`no such membership: ${id}`);
      if (data.role !== undefined) row.role = data.role;
      if (data.llmId !== undefined) row.llmId = data.llmId;
      return row;
    }),
    delete: vi.fn(async (id: string) => { rows = rows.filter((r) => r.id !== id); }),
  } as unknown as IAgentProjectRepository & Record<string, ReturnType<typeof vi.fn>>;

  const agents = {
    getByName: vi.fn(async (name: string) => {
      if (name === 'ghost') throw new NotFoundError(`Agent not found: ${name}`);
      return { id: `agent-${name}`, name };
    }),
    getById: vi.fn(async (id: string) => ({ id, name: id.replace(/^agent-/, '') })),
  } as unknown as AgentService;

  const projects = {
    resolveAndGet: vi.fn(async (name: string) => {
      if (name === 'nowhere') throw new NotFoundError(`Project not found: ${name}`);
      return { id: `proj-${name}`, name };
    }),
    getById: vi.fn(async (id: string) => ({ id, name: id.replace(/^proj-/, '') })),
  } as unknown as ProjectService;

  const llms = {
    getByName: vi.fn(async (name: string) => {
      if (name === 'missing-brain') throw new NotFoundError(`Llm not found: ${name}`);
      return { id: `llm-${name}`, name };
    }),
    getById: vi.fn(async (id: string) => ({ id, name: id.replace(/^llm-/, '') })),
  } as unknown as LlmService;

  return {
    repo, agents, projects, llms,
    service: new AgentProjectService(repo, agents, projects, llms),
    all: () => rows,
  };
}

describe('AgentProjectService — joining and leaving', () => {
  beforeEach(() => { vi.clearAllMocks(); });

  it('joins a project with the default role', async () => {
    const { service } = makeHarness();
    const m = await service.join('alice', 'sre', {});
    expect(m.project.name).toBe('sre');
    expect(m.agent.name).toBe('alice');
    expect(m.role).toBe('developer');
    expect(m.llm).toBeNull();
  });

  it('joins the SAME agent to several projects — the whole point of the junction', async () => {
    const { service } = makeHarness();
    await service.join('alice', 'sre', {});
    await service.join('alice', 'payments', { role: 'security' });

    const memberships = await service.listForAgent('alice');
    expect(memberships.map((m) => m.project.name).sort()).toEqual(['payments', 'sre']);
    expect(memberships.find((m) => m.project.name === 'payments')?.role).toBe('security');
  });

  it('re-joining updates the role instead of 409-ing — repeat applies converge', async () => {
    const { service, repo, all } = makeHarness();
    await service.join('alice', 'sre', { role: 'developer' });
    const second = await service.join('alice', 'sre', { role: 'qa' });

    expect(second.role).toBe('qa');
    expect(all()).toHaveLength(1);
    expect(repo.create).toHaveBeenCalledTimes(1);
    expect(repo.update).toHaveBeenCalledTimes(1);
  });

  it('rejects a role outside the v1 set', async () => {
    const { service } = makeHarness();
    await expect(service.join('alice', 'sre', { role: 'chief-vibes-officer' })).rejects.toThrow();
  });

  it('accepts every v1 role', async () => {
    const { service } = makeHarness();
    for (const role of AgentProjectService.roles()) {
      const m = await service.join('alice', 'sre', { role });
      expect(m.role).toBe(role);
    }
  });

  it('rejects unknown body fields rather than silently dropping them', async () => {
    const { service } = makeHarness();
    // A typo'd `llmName` would otherwise leave the membership with no brain
    // override and no complaint — the exact failure the strict schema exists for.
    await expect(service.join('alice', 'sre', { llmName: 'x' })).rejects.toThrow();
  });

  it('404s on an unknown agent and on an unknown project', async () => {
    const { service } = makeHarness();
    await expect(service.join('ghost', 'sre', {})).rejects.toThrow(/Agent not found/);
    await expect(service.join('alice', 'nowhere', {})).rejects.toThrow(/Project not found/);
  });

  it('leaves a project', async () => {
    const { service, all } = makeHarness([{ agentId: 'agent-alice', projectId: 'proj-sre' }]);
    await service.leave('alice', 'sre');
    expect(all()).toHaveLength(0);
  });

  it('404s when leaving a project the agent never joined — a typo must not no-op', async () => {
    const { service } = makeHarness();
    await expect(service.leave('alice', 'sre')).rejects.toThrow(/is not a member of project 'sre'/);
  });
});

describe('AgentProjectService — the per-membership brain override', () => {
  beforeEach(() => { vi.clearAllMocks(); });

  it('records the named Llm', async () => {
    const { service } = makeHarness();
    const m = await service.join('alice', 'sre', { llm: 'qwen3-thinking' });
    expect(m.llm).toEqual({ id: 'llm-qwen3-thinking', name: 'qwen3-thinking' });
  });

  it('clears the override with an explicit null', async () => {
    const { service } = makeHarness();
    await service.join('alice', 'sre', { llm: 'qwen3-thinking' });
    const cleared = await service.join('alice', 'sre', { llm: null });
    expect(cleared.llm).toBeNull();
  });

  it('leaves an existing override untouched when `llm` is absent', async () => {
    const { service } = makeHarness();
    await service.join('alice', 'sre', { llm: 'qwen3-thinking' });
    const roleOnly = await service.join('alice', 'sre', { role: 'qa' });
    expect(roleOnly.role).toBe('qa');
    expect(roleOnly.llm?.name).toBe('qwen3-thinking');
  });

  it('404s on an Llm that does not exist', async () => {
    const { service } = makeHarness();
    await expect(service.join('alice', 'sre', { llm: 'missing-brain' })).rejects.toThrow(/Llm not found/);
  });

  it('survives a brain that vanished under the membership', async () => {
    // onDelete: SetNull should prevent this, but a torn read must not 500 the
    // whole roster.
    const { service, llms } = makeHarness([{ agentId: 'agent-alice', projectId: 'proj-sre', llmId: 'llm-gone' }]);
    (llms.getById as ReturnType<typeof vi.fn>).mockRejectedValueOnce(new NotFoundError('Llm not found: llm-gone'));
    const [m] = await service.listForAgent('alice');
    expect(m?.llm).toBeNull();
  });
});

describe('AgentProjectService — the reverse view', () => {
  beforeEach(() => { vi.clearAllMocks(); });

  it('lists the whole roster for a project, with roles', async () => {
    const { service } = makeHarness([
      { agentId: 'agent-alice', projectId: 'proj-sre', role: 'sre' },
      { agentId: 'agent-bob', projectId: 'proj-sre', role: 'qa' },
      { agentId: 'agent-carol', projectId: 'proj-payments', role: 'security' },
    ]);
    const roster = await service.listForProject('sre');
    expect(roster.map((m) => `${m.agent.name}:${m.role}`)).toEqual(['alice:sre', 'bob:qa']);
  });

  it('404s on an unknown project', async () => {
    const { service } = makeHarness();
    await expect(service.listForProject('nowhere')).rejects.toThrow(/Project not found/);
  });
});