import {
  OperationsHealth,
  SafeAuditEvent,
  ComponentHealthStatus,
  HealthComponentKey,
} from '../components/ops/types';

export const HEALTH_COMPONENT_METADATA: Record<
  HealthComponentKey,
  { name: string; description: string }
> = {
  operations_api: {
    name: 'Operations API',
    description: 'FastAPI core endpoint runtime & ingress',
  },
  operations_database: {
    name: 'Operations Database',
    description: 'PostgreSQL ops schema relational persistence',
  },
  session_validation: {
    name: 'Session Validation',
    description: '__Host-motorsignal_ops token verification & authority',
  },
  audit_persistence: {
    name: 'Audit Persistence',
    description: 'Immutable operational security activity persistence',
  },
};

export const APPROVED_AUDIT_METADATA_KEYS = new Set([
  'component',
  'status_code',
  'subsystem',
  'duration_ms',
  'policy',
  'action_scope',
  'session_valid',
  'mfa_verified',
  'migration_version',
  'records_affected',
]);

export function isValidHealthStatus(status: unknown): status is ComponentHealthStatus {
  return (
    status === 'available' ||
    status === 'degraded' ||
    status === 'unavailable' ||
    status === 'unknown'
  );
}

export function normalizeHealthResponse(raw: unknown): OperationsHealth {
  const fallbackCheckedAt = new Date().toISOString();
  if (!raw || typeof raw !== 'object') {
    return {
      status: 'unavailable',
      checked_at: fallbackCheckedAt,
      components: {
        operations_api: { status: 'unavailable', description: HEALTH_COMPONENT_METADATA.operations_api.description },
        operations_database: { status: 'unavailable', description: HEALTH_COMPONENT_METADATA.operations_database.description },
        session_validation: { status: 'unavailable', description: HEALTH_COMPONENT_METADATA.session_validation.description },
        audit_persistence: { status: 'unavailable', description: HEALTH_COMPONENT_METADATA.audit_persistence.description },
      },
    };
  }

  const obj = raw as Record<string, unknown>;
  const rawStatus = obj.status;
  const overallStatus: ComponentHealthStatus = isValidHealthStatus(rawStatus)
    ? rawStatus
    : 'unknown';

  const checkedAt =
    typeof obj.checked_at === 'string' && obj.checked_at.length > 0
      ? obj.checked_at
      : fallbackCheckedAt;

  const rawComponents =
    obj.components && typeof obj.components === 'object'
      ? (obj.components as Record<string, unknown>)
      : {};

  const keys: HealthComponentKey[] = [
    'operations_api',
    'operations_database',
    'session_validation',
    'audit_persistence',
  ];

  const components: Record<
    HealthComponentKey,
    { status: ComponentHealthStatus; description: string }
  > = {
    operations_api: { status: 'unknown', description: HEALTH_COMPONENT_METADATA.operations_api.description },
    operations_database: { status: 'unknown', description: HEALTH_COMPONENT_METADATA.operations_database.description },
    session_validation: { status: 'unknown', description: HEALTH_COMPONENT_METADATA.session_validation.description },
    audit_persistence: { status: 'unknown', description: HEALTH_COMPONENT_METADATA.audit_persistence.description },
  };

  for (const key of keys) {
    const rawComp = rawComponents[key] as Record<string, unknown> | undefined;
    const compStatus = rawComp && isValidHealthStatus(rawComp.status)
      ? rawComp.status
      : isValidHealthStatus(obj[key])
      ? (obj[key] as ComponentHealthStatus)
      : overallStatus;

    components[key] = {
      status: compStatus,
      description: (rawComp?.description as string) || HEALTH_COMPONENT_METADATA[key].description,
    };
  }

  return {
    status: overallStatus,
    checked_at: checkedAt,
    components,
  };
}

export function sanitizeAuditEvent(raw: unknown): SafeAuditEvent | null {
  if (!raw || typeof raw !== 'object') {
    return null; // Fail closed
  }

  const obj = raw as Record<string, unknown>;

  // Required: timestamp (ISO string)
  if (typeof obj.timestamp !== 'string' || !obj.timestamp.trim()) {
    return null;
  }
  const timestamp = obj.timestamp.trim();

  // Required: action
  if (typeof obj.action !== 'string' || !obj.action.trim()) {
    return null;
  }
  const action = obj.action.trim();

  // Required: result
  if (typeof obj.result !== 'string' || !obj.result.trim()) {
    return null;
  }
  const result = obj.result.trim();

  // Required: actor_identity (exact OPS-3B contract, no actor_email alias)
  if (typeof obj.actor_identity !== 'string' || !obj.actor_identity.trim()) {
    return null; // Fail closed: missing verified identity
  }
  const actor_identity = obj.actor_identity.trim();

  // Optional transport ID (unrendered in UI)
  const id =
    typeof obj.id === 'string' && obj.id.trim()
      ? obj.id.trim()
      : undefined;

  // Optional: actor_role
  const actor_role =
    typeof obj.actor_role === 'string' && obj.actor_role.trim()
      ? obj.actor_role.trim()
      : undefined;

  // Optional: target_resource (exact OPS-3B contract, no target alias)
  const target_resource =
    typeof obj.target_resource === 'string' && obj.target_resource.trim()
      ? obj.target_resource.trim()
      : undefined;

  // Optional: reason_code
  const reason_code =
    typeof obj.reason_code === 'string' && obj.reason_code.trim()
      ? obj.reason_code.trim()
      : undefined;

  // Optional: case_reference
  const case_reference =
    typeof obj.case_reference === 'string' && obj.case_reference.trim()
      ? obj.case_reference.trim()
      : undefined;

  // Explicit Allowlist Metadata Projection only
  let metadata: Record<string, string | number | boolean> | undefined = undefined;
  if (obj.metadata && typeof obj.metadata === 'object' && !Array.isArray(obj.metadata)) {
    const rawMeta = obj.metadata as Record<string, unknown>;
    const safeMeta: Record<string, string | number | boolean> = {};
    for (const [k, v] of Object.entries(rawMeta)) {
      if (!APPROVED_AUDIT_METADATA_KEYS.has(k)) {
        continue; // Drop unapproved metadata key
      }
      if (typeof v === 'string' && v.length <= 100) {
        safeMeta[k] = v;
      } else if (typeof v === 'number' || typeof v === 'boolean') {
        safeMeta[k] = v;
      }
    }
    if (Object.keys(safeMeta).length > 0) {
      metadata = safeMeta;
    }
  }

  return {
    id,
    timestamp,
    action,
    result,
    actor_identity,
    actor_role,
    target_resource,
    reason_code,
    case_reference,
    metadata,
  };
}