// v1.13.11-a: Zod schemas for every WebSocket frame published by the server.
// Validation runs both on send (broker.publishFrame / publishUserFrame) and
// on receive (apps/web/src/hooks/useSessionStream + useUserEvents). Catches
// silent protocol drift between publisher and consumer.
//
// IMPORTANT: This file is duplicated byte-identical at
// apps/web/src/api/ws-frames.ts. The two apps have separate tsconfigs and
// no path alias; the duplication is sync-by-hand. A test asserts the two
// files match. If you change one, change the other.
//
// Per-kind payload schemas (tool_call args, message_parts payloads, etc.)
// stay z.unknown() in v1.13.11. Frame-level drift detection is the goal;
// deep payload validation is follow-up work.

import { z } from 'zod';

// ---- shared primitives -----------------------------------------------------

const Uuid = z.string().uuid();
// Tool call IDs are model-emitted (e.g. "call_abc123") — not UUIDs.
const ToolCallId = z.string().min(1);
// v1.13.12 fix: postgres returns timestamp columns as JS Date objects, not
// strings. The publish sites pass them through unchanged, so the schema must
// tolerate both. preprocess converts Date → ISO string before string-validation;
// on the web side (where frames arrive via JSON.parse) it's a no-op. Before
// this fix, every message_complete / session_updated / chat_updated frame
// failed validation and got dropped — symptoms: token tracking blank in UI,
// status stuck at 'streaming' tripping the 60s stale-stream banner.
const IsoTimestamp = z.preprocess(
  (v) => (v instanceof Date ? v.toISOString() : v),
  z.string().min(1),
);

const ChatStatusValue = z.enum([
  'streaming',
  'tool_running',
  'waiting_for_input',
  'idle',
  'error',
]);

const ErrorReasonValue = z.enum([
  'llm_provider_error',
  'doom_loop',
  'doom_loop_summary_failed',
  'cap_hit',
  'cap_hit_summary_failed',
]);

const MessageRoleValue = z.enum(['user', 'assistant', 'system', 'tool']);

const ToolCallShape = z.object({
  id: ToolCallId,
  name: z.string().min(1),
  args: z.record(z.string(), z.unknown()),
});

// Free-form bags: opaque to the frame schema; deep validation is out of
// scope for v1.13.11 (frame-level drift detection is the goal; per-kind
// payload narrowing is follow-up work). z.unknown() means the consumer
// must narrow before reading — TypeScript-side this is fine because every
// consumer already operates on the hand-maintained Project / Chat / Session
// / WorkspacePane types (the brief's "Don't strip existing types yet"
// rule), and the Zod-typed shape is only used at the publishFrame boundary.
const OpaqueObject = z.unknown();

// ---- per-session channel frames --------------------------------------------

export const SnapshotFrame = z.object({
  type: z.literal('snapshot'),
  messages: z.array(OpaqueObject),
});

export const MessageStartedFrame = z.object({
  type: z.literal('message_started'),
  message_id: Uuid,
  chat_id: Uuid.optional(),
  role: MessageRoleValue,
});

export const DeltaFrame = z.object({
  type: z.literal('delta'),
  message_id: Uuid,
  chat_id: Uuid.optional(),
  content: z.string(),
});

export const ReasoningDeltaFrame = z.object({
  type: z.literal('reasoning_delta'),
  message_id: Uuid,
  chat_id: Uuid.optional(),
  content: z.string(),
});

export const ToolCallFrame = z.object({
  type: z.literal('tool_call'),
  message_id: Uuid,
  chat_id: Uuid.optional(),
  tool_call: ToolCallShape,
});

export const ToolResultFrame = z.object({
  type: z.literal('tool_result'),
  tool_message_id: Uuid,
  chat_id: Uuid.optional(),
  tool_call_id: ToolCallId,
  output: z.unknown(),
  truncated: z.boolean(),
  error: z.string().optional(),
});

export const MessageCompleteFrame = z.object({
  type: z.literal('message_complete'),
  message_id: Uuid,
  chat_id: Uuid.optional(),
  tokens_used: z.number().int().nonnegative().nullable().optional(),
  ctx_used: z.number().int().nonnegative().nullable().optional(),
  ctx_max: z.number().int().positive().nullable().optional(),
  started_at: IsoTimestamp.nullable().optional(),
  finished_at: IsoTimestamp.nullable().optional(),
  model: z.string().optional(),
  metadata: OpaqueObject.nullable().optional(),
});

export const UsageFrame = z.object({
  type: z.literal('usage'),
  message_id: Uuid,
  chat_id: Uuid.optional(),
  completion_tokens: z.number().int().nonnegative().nullable(),
  ctx_used: z.number().int().nonnegative().nullable(),
  ctx_max: z.number().int().positive().nullable(),
});

export const MessagesDeletedFrame = z.object({
  type: z.literal('messages_deleted'),
  message_ids: z.array(Uuid),
  chat_id: Uuid.optional(),
});

export const ChatRenamedFrame = z.object({
  type: z.literal('chat_renamed'),
  chat_id: Uuid,
  name: z.string(),
});

export const CompactedFrame = z.object({
  type: z.literal('compacted'),
  session_id: Uuid,
  chat_id: Uuid,
  summary_message_id: Uuid,
});

export const ErrorFrame = z.object({
  type: z.literal('error'),
  message_id: Uuid.optional(),
  chat_id: Uuid.optional(),
  error: z.string(),
  reason: ErrorReasonValue.optional(),
});

// ---- per-user channel frames (sidebar refresh) -----------------------------

export const ChatStatusFrame = z.object({
  type: z.literal('chat_status'),
  chat_id: Uuid,
  status: ChatStatusValue,
  at: IsoTimestamp,
  reason: ErrorReasonValue.optional(),
});

export const SessionUpdatedFrame = z.object({
  type: z.literal('session_updated'),
  session_id: Uuid,
  project_id: Uuid,
  name: z.string(),
  updated_at: IsoTimestamp,
});

export const SessionRenamedFrame = z.object({
  type: z.literal('session_renamed'),
  session_id: Uuid,
  name: z.string(),
});

export const SessionCreatedFrame = z.object({
  type: z.literal('session_created'),
  session: OpaqueObject,
  project_id: Uuid,
});

export const SessionArchivedFrame = z.object({
  type: z.literal('session_archived'),
  session_id: Uuid,
  project_id: Uuid,
});

export const SessionDeletedFrame = z.object({
  type: z.literal('session_deleted'),
  session_id: Uuid,
  project_id: Uuid,
});

export const SessionWorkspaceUpdatedFrame = z.object({
  type: z.literal('session_workspace_updated'),
  session_id: Uuid,
  workspace_panes: z.array(OpaqueObject),
});

export const ChatCreatedFrame = z.object({
  type: z.literal('chat_created'),
  chat: OpaqueObject,
  session_id: Uuid,
});

export const ChatUpdatedFrame = z.object({
  type: z.literal('chat_updated'),
  chat_id: Uuid,
  session_id: Uuid,
  name: z.string().nullable(),
  updated_at: IsoTimestamp,
});

export const ChatArchivedFrame = z.object({
  type: z.literal('chat_archived'),
  chat_id: Uuid,
  session_id: Uuid,
});

export const ChatUnarchivedFrame = z.object({
  type: z.literal('chat_unarchived'),
  chat: OpaqueObject,
});

export const ChatDeletedFrame = z.object({
  type: z.literal('chat_deleted'),
  chat_id: Uuid,
  session_id: Uuid,
});

export const ProjectCreatedFrame = z.object({
  type: z.literal('project_created'),
  project: OpaqueObject,
});

export const ProjectArchivedFrame = z.object({
  type: z.literal('project_archived'),
  project_id: Uuid,
});

export const ProjectUnarchivedFrame = z.object({
  type: z.literal('project_unarchived'),
  project: OpaqueObject,
});

export const ProjectUpdatedFrame = z.object({
  type: z.literal('project_updated'),
  project_id: Uuid,
  name: z.string(),
});

export const ProjectDeletedFrame = z.object({
  type: z.literal('project_deleted'),
  project_id: Uuid,
});

const PermissionOptionShape = z.object({
  option_id: z.string(),
  label: z.string(),
});

export const PermissionRequestedFrame = z.object({
  type: z.literal('permission_requested'),
  task_id: Uuid,
  session_id: Uuid,
  kind: z.enum(['tool', 'question', 'plan', 'elicitation']).optional(),
  tool_title: z.string().optional(),
  input: z.record(z.unknown()).optional(),
  options: z.array(PermissionOptionShape),
});

export const PermissionResolvedFrame = z.object({
  type: z.literal('permission_resolved'),
  task_id: Uuid,
  session_id: Uuid,
});

const AgentCommandShape = z.object({
  name: z.string(),
  description: z.string().optional(),
});

export const AgentCommandsFrame = z.object({
  type: z.literal('agent_commands'),
  task_id: Uuid,
  session_id: Uuid,
  commands: z.array(AgentCommandShape),
});

// ---- discriminated union ---------------------------------------------------

export const WsFrameSchema = z.discriminatedUnion('type', [
  // per-session
  SnapshotFrame,
  MessageStartedFrame,
  DeltaFrame,
  ReasoningDeltaFrame,
  ToolCallFrame,
  ToolResultFrame,
  MessageCompleteFrame,
  UsageFrame,
  MessagesDeletedFrame,
  ChatRenamedFrame,
  CompactedFrame,
  ErrorFrame,
  PermissionRequestedFrame,
  PermissionResolvedFrame,
  AgentCommandsFrame,
  // per-user
  ChatStatusFrame,
  SessionUpdatedFrame,
  SessionRenamedFrame,
  SessionCreatedFrame,
  SessionArchivedFrame,
  SessionDeletedFrame,
  SessionWorkspaceUpdatedFrame,
  ChatCreatedFrame,
  ChatUpdatedFrame,
  ChatArchivedFrame,
  ChatUnarchivedFrame,
  ChatDeletedFrame,
  ProjectCreatedFrame,
  ProjectArchivedFrame,
  ProjectUnarchivedFrame,
  ProjectUpdatedFrame,
  ProjectDeletedFrame,
]);

export type WsFrame = z.infer<typeof WsFrameSchema>;

// Convenience: the set of known frame types. Useful for the publishFrame
// helper to log the offending type name when validation fails. Kept in sync
// by hand with the discriminated union above.
export const KNOWN_FRAME_TYPES: readonly WsFrame['type'][] = [
  'snapshot',
  'message_started',
  'delta',
  'reasoning_delta',
  'tool_call',
  'tool_result',
  'message_complete',
  'usage',
  'messages_deleted',
  'chat_renamed',
  'compacted',
  'error',
  'permission_requested',
  'permission_resolved',
  'agent_commands',
  'chat_status',
  'session_updated',
  'session_renamed',
  'session_created',
  'session_archived',
  'session_deleted',
  'session_workspace_updated',
  'chat_created',
  'chat_updated',
  'chat_archived',
  'chat_unarchived',
  'chat_deleted',
  'project_created',
  'project_archived',
  'project_unarchived',
  'project_updated',
  'project_deleted',
] as const;