export type Price = {
  amount: number;
  currency: string;
  model: string;
};

export type ListingStats = {
  installs?: number;
  proposals_shown?: number;
  proposals_accepted?: number;
};

export type ListingSummary = {
  listing_id: string;
  name: string;
  summary: string;
  category?: string;
  price: Price;
  seller: string;
  stats?: ListingStats;
  score?: number;
};

export type ListingDetail = ListingSummary & {
  evidence_summary: string;
  permissions: string[];
  install_ref?: string;
  install_command: string;
  solution_version?: string;
  version?: string;
};

export type Transaction = {
  ts: string;
  from: string;
  to: string;
  amount: number;
  reason: string;
  ref?: string;
};

export type Wallet = {
  operator_id: string;
  balance: number;
  as_of?: string;
  transactions: Transaction[];
};

export type Economy = {
  operators: Array<{ operator_id: string; balance: number }>;
  audit?: { date: string; url: string };
};

export type Governance = {
  open_prs: Array<{ number: number; title: string; age_days: number; labels: string[]; url: string }>;
  listings: Array<{ listing_id: string; status: string; url: string }>;
};

export type PanelName = 'search' | 'listing' | 'wallet' | 'economy' | 'governance' | 'login';

export class ApiError extends Error {
  status: number;
  panel?: string;

  constructor(message: string, status: number, panel?: string) {
    super(message);
    this.name = 'ApiError';
    this.status = status;
    this.panel = panel;
  }
}

async function request<T>(path: string, init?: RequestInit): Promise<T> {
  const response = await fetch(path, {
    credentials: 'include',
    headers: {
      'Content-Type': 'application/json',
      ...(init?.headers ?? {}),
    },
    ...init,
  });

  if (response.status === 401) {
    if (window.location.hash !== '#/login') {
      window.location.hash = '#/login';
    }
    throw new ApiError('Login required', 401);
  }

  if (response.status === 502) {
    const body = (await response.json().catch(() => null)) as { error?: string; panel?: string } | null;
    throw new ApiError(body?.error ?? 'Panel is temporarily unavailable', 502, body?.panel);
  }

  if (!response.ok) {
    const body = (await response.json().catch(() => null)) as { error?: string } | null;
    throw new ApiError(body?.error ?? `Request failed (${response.status})`, response.status);
  }

  if (response.status === 204) {
    return undefined as T;
  }

  return (await response.json()) as T;
}

export const api = {
  login(passcode: string) {
    return request<void>('/api/login', {
      method: 'POST',
      body: JSON.stringify({ passcode }),
    });
  },
  search(q: string, limit = 10) {
    const params = new URLSearchParams({ q, limit: String(limit) });
    return request<ListingSummary[]>(`/api/search?${params}`);
  },
  listing(listingId: string) {
    return request<ListingDetail>(`/api/listing/${encodeURIComponent(listingId)}`);
  },
  wallet(operatorId: string) {
    return request<Wallet>(`/api/wallet/${encodeURIComponent(operatorId)}`);
  },
  economy() {
    return request<Economy>('/api/economy');
  },
  governance() {
    return request<Governance>('/api/governance');
  },
};