export const API_V1_PREFIX = '/api/v1' as const;
export const MAX_PAGE_SIZE = 100 as const;
export const SORT_DIRECTIONS = ['asc', 'desc'] as const;
export const CAPABILITY_STATUSES = [
  'supported',
  'unsupported',
  'auth-required',
  'degraded',
  'unknown',
] as const;
export const FRESHNESS_STATUSES = ['fresh', 'stale', 'expired', 'unknown'] as const;

export type SortDirection = (typeof SORT_DIRECTIONS)[number];
export type CapabilityStatus = (typeof CAPABILITY_STATUSES)[number];
export type SnapshotFreshness = (typeof FRESHNESS_STATUSES)[number];
export type Revision = number;

/** Page ordering is stable: the resource id is always the final ascending tie-breaker. */
export interface PageQuery<SortField extends string> {
  readonly page?: number;
  readonly pageSize?: number;
  readonly sort?: SortField;
  readonly direction?: SortDirection;
}
export interface PageMeta {
  readonly page: number;
  readonly pageSize: number;
  readonly total: number;
}
export interface PageEnvelope<T> {
  readonly items: readonly T[];
  readonly page: PageMeta;
}

export type PasswordUpdate =
  | { readonly action: 'preserve' }
  | { readonly action: 'set'; readonly password: string }
  | { readonly action: 'clear' };

export interface InstanceInput {
  readonly name: string;
  readonly origin: string;
  readonly tags?: readonly string[];
  readonly password?: PasswordUpdate;
}
export interface InstancePatch {
  readonly name?: string;
  readonly origin?: string;
  readonly tags?: readonly string[];
  readonly password?: PasswordUpdate;
}
export interface LoginInput {
  /** One-shot input; omit to resolve the saved credential reference server-side. */
  readonly password?: string;
}
export interface Instance {
  readonly id: string;
  readonly name: string;
  readonly origin: string;
  readonly tags: readonly string[];
  readonly revision: Revision;
  readonly capabilityStatus: CapabilityStatus;
  readonly freshness: SnapshotFreshness;
  readonly credentialConfigured: boolean;
}
export interface InstanceFilters {
  readonly search?: string;
  readonly capabilityStatus?: CapabilityStatus;
  readonly freshness?: SnapshotFreshness;
  readonly tag?: string;
  readonly credentialConfigured?: boolean;
}
export type InstancePageQuery = PageQuery<'name' | 'status' | 'freshness' | 'updatedAt'> &
  InstanceFilters;
export type InstancePage = PageEnvelope<Instance>;

export interface SessionMetadata {
  readonly instanceId: string;
  readonly authenticated: boolean;
  readonly checkedAt: string;
}