/**
 * Fleet API client — typed wrapper for the fleet coordinator endpoints.
 * Follows the same pattern as tracker-client.ts.
 * Degrades gracefully: 404s return null, network errors return defaults.
 */

import { createApiClient } from '@bytelyst/api-client';

// ── Types ───────────────────────────────────────────────────────────────────

export interface FleetJob {
  id: string;
  productId: string;
  stage: string;
  idempotencyKey: string;
  bodyMd: string;
  priority: string;
  priorityOrder: number;
  capabilities: string[];
  kind: string;
  parentId?: string;
  attempts: number;
  leaseEpoch: number;
  createdAt: string;
  updatedAt: string;
}

export interface FleetFactory {
  id: string;
  productId: string;
  factoryId: string;
  capabilities: string[];
  health: 'ok' | 'degraded' | 'down';
  load: number;
  seatLimit: number;
  lastHeartbeatAt: string;
}

export interface FleetRun {
  id: string;
  jobId: string;
  attempt: number;
  factoryId?: string;
  engine: string;
  startedAt: string;
  endedAt?: string;
  result?: string;
  insights: Record<string, unknown>;
}

export interface FleetEvent {
  id: string;
  jobId: string;
  seq: number;
  type: string;
  at: string;
  actor?: string;
  data: Record<string, unknown>;
}

export interface FleetArtifact {
  id: string;
  jobId: string;
  kind: string;
  contentType: string;
  sizeBytes: number;
  createdAt: string;
}

export interface FleetBudget {
  id: string;
  productId: string;
  ceilingUsd: number;
  window: string;
  spentUsd: number;
  status: 'active' | 'paused';
  updatedAt: string;
}

export interface DagNode {
  id: string;
  idempotencyKey: string;
  stage: string;
  priority: string;
  kind: string;
  parentId?: string;
  children: DagNode[];
}

// ── Client ──────────────────────────────────────────────────────────────────

const fleetApi = createApiClient({
  baseUrl: '/api/fleet',
  getToken: () => (typeof window !== 'undefined' ? localStorage.getItem('tracker_token') : null),
});

function apiFetch<T>(path: string, options?: RequestInit): Promise<T> {
  const extra: Record<string, string> = {};
  if (typeof window !== 'undefined') {
    const pid = localStorage.getItem('tracker_selected_product');
    if (pid) extra['x-product-id'] = pid;
  }
  return fleetApi.fetch<T>(path, {
    ...options,
    headers: { ...extra, ...(options?.headers as Record<string, string>) },
  });
}

/** Graceful fetch — returns null on 404 instead of throwing. */
async function apiFetchOptional<T>(path: string, options?: RequestInit): Promise<T | null> {
  try {
    return await apiFetch<T>(path, options);
  } catch (err: unknown) {
    if (err instanceof Error && err.message.includes('404')) return null;
    throw err;
  }
}

// ── Jobs ────────────────────────────────────────────────────────────────────

export interface ListJobsParams {
  stage?: string;
  productId?: string;
  limit?: number;
  offset?: number;
}

export async function listJobs(params?: ListJobsParams): Promise<{ jobs: FleetJob[] }> {
  const qs = params ? `?${new URLSearchParams(params as Record<string, string>).toString()}` : '';
  return apiFetch(`/jobs${qs}`);
}

export async function getJob(id: string): Promise<FleetJob | null> {
  return apiFetchOptional(`/jobs/${id}`);
}

export async function patchJob(
  id: string,
  body: { leaseEpoch: number; stage: string }
): Promise<FleetJob> {
  return apiFetch(`/jobs/${id}`, { method: 'PATCH', body: JSON.stringify(body) });
}

export async function getJobRuns(jobId: string): Promise<{ runs: FleetRun[] }> {
  return apiFetch(`/jobs/${jobId}/runs`);
}

export async function getJobEvents(jobId: string): Promise<{ events: FleetEvent[] }> {
  return apiFetch(`/jobs/${jobId}/events`);
}

export async function getJobArtifacts(jobId: string): Promise<{ artifacts: FleetArtifact[] }> {
  return apiFetch(`/jobs/${jobId}/artifacts`);
}

export async function getJobDag(jobId: string): Promise<{ dag: DagNode } | null> {
  return apiFetchOptional(`/jobs/${jobId}/dag`);
}

// ── Factories ───────────────────────────────────────────────────────────────

export async function listFactories(): Promise<{ factories: FleetFactory[] }> {
  try {
    return await apiFetch('/factories');
  } catch {
    return { factories: [] };
  }
}

// ── Budgets ─────────────────────────────────────────────────────────────────

export async function getBudget(productId: string): Promise<FleetBudget | null> {
  return apiFetchOptional(`/budgets/${productId}`);
}

export async function upsertBudget(
  productId: string,
  ceilingUsd: number,
  window: string
): Promise<FleetBudget> {
  return apiFetch(`/budgets/${productId}`, {
    method: 'PUT',
    body: JSON.stringify({ ceilingUsd, window }),
  });
}

export async function pauseBudget(productId: string): Promise<FleetBudget> {
  return apiFetch(`/budgets/${productId}/pause`, { method: 'POST' });
}

export async function resumeBudget(productId: string): Promise<FleetBudget> {
  return apiFetch(`/budgets/${productId}/resume`, { method: 'POST' });
}