export type ServerStatus = "pending" | "active" | "offline";
export type KeySource = "uploaded" | "generated";

export interface PackageUpdate {
  name: string;
  current_version?: string;
  new_version: string;
}

export interface Server {
  id: string;
  server_id: string;
  hostname: string;
  ip_address: string;
  os_info: string;
  status: ServerStatus;
  agent_version?: string;
  last_seen: string;
  created_at: string;
  available_updates?: PackageUpdate[];
  updates_checked_at?: string;
}

export interface Key {
  id: string;
  key_id: string;
  label: string;
  public_key: string;
  fingerprint: string;
  source: KeySource;
  generated_by_server_id?: string;
  has_private_key: boolean;
  created_at: string;
  assigned_count?: number;
}

export interface Assignment {
  id: string;
  key_id: string;
  server_id: string;
  assigned_at: string;
  revoked_at: string | null;
}

export interface AuditEvent {
  id: string;
  event_type: string;
  actor: string;
  server_id?: string;
  key_id?: string;
  details: string;
  created_at: string;
}

export interface AlertSettings {
  enabled: boolean;
  webhook_url: string;
  offline_threshold_minutes: number;
}

export interface EmailSettings {
  enabled: boolean;
  smtp_host: string;
  smtp_port: number;
  username: string;
  password: string;
  from_addr: string;
  to_addrs: string[];
  use_tls: boolean;
}

export interface SecretsSettings {
  read_token_set: boolean;
  rotated_at?: string;
}

export interface Settings {
  alerts: AlertSettings;
  email: EmailSettings;
  secrets: SecretsSettings;
}

export interface SecretGroupSummary {
  group: string;
  key_count: number;
  updated_at: string;
}

export interface Secret {
  group: string;
  key: string;
  updated_at: string;
}

export interface NewServerResponse {
  server_id: string;
  pre_reg_token: string;
  install_command: string;
}

export interface GenerateKeyOptions {
  label: string;
  key_type: "ed25519" | "rsa" | "ecdsa";
  key_size?: number;
  passphrase?: string;
  comment?: string;
}

export interface KeyWithAssignments extends Key {
  assignments: (Assignment & { server: Server })[];
}

export interface ServerWithKeys extends Server {
  keys: (Assignment & { key: Key })[];
}

class ApiError extends Error {
  constructor(
    public status: number,
    message: string
  ) {
    super(message);
    this.name = "ApiError";
  }
}

async function request<T>(path: string, options?: RequestInit): Promise<T> {
  const res = await fetch(`/api${path}`, {
    credentials: "include",
    headers: {
      "Content-Type": "application/json",
      ...options?.headers,
    },
    ...options,
  });

  if (!res.ok) {
    const text = await res.text().catch(() => res.statusText);
    throw new ApiError(res.status, text || `HTTP ${res.status}`);
  }

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

  return res.json();
}

export const api = {
  // Servers
  listServers(): Promise<Server[]> {
    return request<Server[]>("/servers");
  },

  getServer(serverId: string): Promise<ServerWithKeys> {
    return request<ServerWithKeys>(`/servers/${serverId}`);
  },

  createServer(): Promise<NewServerResponse> {
    return request<NewServerResponse>("/servers/new", { method: "POST" });
  },

  deleteServer(serverId: string): Promise<void> {
    return request<void>(`/servers/${serverId}`, { method: "DELETE" });
  },

  generateKeyForServer(serverId: string, opts: GenerateKeyOptions): Promise<{ command_id: string }> {
    return request<{ command_id: string }>(`/servers/${serverId}/generate-key`, {
      method: "POST",
      body: JSON.stringify(opts),
    });
  },

  getUpdateCommand(): string {
    return `curl -fsSL "${window.location.origin}/update" | bash`;
  },

  getLatestAgentVersion(): Promise<{ version: string }> {
    return request<{ version: string }>("/agent/latest-version");
  },

  updateAgent(serverId: string): Promise<{ message: string; version: string }> {
    return request<{ message: string; version: string }>(`/servers/${serverId}/update-agent`, {
      method: "POST",
    });
  },

  applyUpdates(serverId: string): Promise<{ message: string }> {
    return request<{ message: string }>(`/servers/${serverId}/apply-updates`, {
      method: "POST",
    });
  },

  // Audit
  listAuditEvents(limit?: number): Promise<AuditEvent[]> {
    const qs = limit ? `?limit=${limit}` : "";
    return request<AuditEvent[]>(`/audit${qs}`);
  },

  // Settings
  getSettings(): Promise<Settings> {
    return request<Settings>("/settings");
  },

  saveSettings(settings: { alerts: AlertSettings; email: EmailSettings }): Promise<{ saved: boolean }> {
    return request<{ saved: boolean }>("/settings", {
      method: "PUT",
      body: JSON.stringify(settings),
    });
  },

  rotateSecretsToken(): Promise<{ token: string }> {
    return request<{ token: string }>("/settings/secrets-token", { method: "POST" });
  },

  // Secrets
  listSecretGroups(): Promise<SecretGroupSummary[]> {
    return request<SecretGroupSummary[]>("/secrets");
  },

  createSecretGroup(group: string, values: Record<string, string>): Promise<{ group: string }> {
    return request<{ group: string }>("/secrets", {
      method: "POST",
      body: JSON.stringify({ group, values }),
    });
  },

  getSecretGroup(group: string): Promise<{ group: string; secrets: Secret[] }> {
    return request<{ group: string; secrets: Secret[] }>(`/secrets/${encodeURIComponent(group)}`);
  },

  putSecrets(group: string, values: Record<string, string>): Promise<{ saved: boolean }> {
    return request<{ saved: boolean }>(`/secrets/${encodeURIComponent(group)}`, {
      method: "PUT",
      body: JSON.stringify(values),
    });
  },

  revealSecret(group: string, key: string): Promise<{ value: string }> {
    return request<{ value: string }>(`/secrets/${encodeURIComponent(group)}/reveal`, {
      method: "POST",
      body: JSON.stringify({ key }),
    });
  },

  deleteSecret(group: string, key: string): Promise<void> {
    return request<void>(`/secrets/${encodeURIComponent(group)}/${encodeURIComponent(key)}`, {
      method: "DELETE",
    });
  },

  deleteSecretGroup(group: string): Promise<void> {
    return request<void>(`/secrets/${encodeURIComponent(group)}`, { method: "DELETE" });
  },

  // Keys
  listKeys(): Promise<Key[]> {
    return request<Key[]>("/keys");
  },

  getKey(keyId: string): Promise<KeyWithAssignments> {
    return request<KeyWithAssignments>(`/keys/${keyId}`);
  },

  uploadKey(label: string, public_key: string, private_key?: string): Promise<Key> {
    return request<Key>("/keys", {
      method: "POST",
      body: JSON.stringify({ label, public_key, private_key: private_key || undefined }),
    });
  },

  getPrivateKey(keyId: string): Promise<{ private_key: string }> {
    return request<{ private_key: string }>(`/keys/${keyId}/private-key`);
  },

  deleteKey(keyId: string): Promise<void> {
    return request<void>(`/keys/${keyId}`, { method: "DELETE" });
  },

  // Assignments
  assignKey(keyId: string, serverId: string): Promise<Assignment> {
    return request<Assignment>(`/keys/${keyId}/assign`, {
      method: "POST",
      body: JSON.stringify({ server_id: serverId }),
    });
  },

  revokeKey(keyId: string, serverId: string): Promise<void> {
    return request<void>(`/keys/${keyId}/assign/${serverId}`, {
      method: "DELETE",
    });
  },
};