/**
 * PearData P2P protocol — control plane + metric streaming.
 *
 * PROTOCOL_VERSION is negotiated via `handshake`. Bump on breaking RPC shapes.
 * Additive methods may land without a bump when clients tolerate unknown methods.
 *
 * Planes:
 *   - Control/metadata: handshake, info, ACL, invites, jobs, alerts config
 *   - Metrics query: contexts, charts, historical data (hot path)
 *   - Push streams: live samples, anomalies, health events
 */

export const PROTOCOL = 'peardata/rpc'
export const PROTOCOL_VERSION = 1
export const APP_NAME = 'peardata'
export const APP_VERSION = '0.1.0'

/** Roles for capability ACL. Secure default peer role is viewer. */
export const Roles = Object.freeze({
  viewer: 'viewer',
  operator: 'operator',
  admin: 'admin',
})

const ROLE_RANK = {
  [Roles.viewer]: 1,
  [Roles.operator]: 2,
  [Roles.admin]: 3,
}

/**
 * @param {string} role
 * @param {string} required
 */
export function roleAllows(role, required) {
  const have = ROLE_RANK[role] || 0
  const need = ROLE_RANK[required] || ROLE_RANK[Roles.admin]
  return have >= need
}

/**
 * Minimum role required per method (default admin for unknown).
 */
export const MethodRoles = Object.freeze({
  // session
  handshake: Roles.viewer,
  ping: Roles.viewer,
  getServerInfo: Roles.viewer,
  getAuthStatus: Roles.viewer,
  setDisplayName: Roles.viewer,

  // agent / node metadata
  getNodeInfo: Roles.viewer,
  getHealth: Roles.viewer,

  // metrics discovery + query
  listContexts: Roles.viewer,
  getContext: Roles.viewer,
  listCharts: Roles.viewer,
  getChart: Roles.viewer,
  queryData: Roles.viewer,
  getAllMetrics: Roles.viewer,
  getWeights: Roles.viewer,

  // AI / QVAC tool-friendly composites (viewer read)
  getHostSnapshot: Roles.viewer,
  searchCharts: Roles.viewer,
  summarizeChart: Roles.viewer,
  investigateHost: Roles.viewer,
  hotMetrics: Roles.viewer,
  relatedCharts: Roles.viewer,
  compareChartWindows: Roles.viewer,
  summarizeCharts: Roles.viewer,

  // live subscription control
  subscribeMetrics: Roles.viewer,
  unsubscribeMetrics: Roles.viewer,
  subscribeAnomalies: Roles.viewer,
  unsubscribeAnomalies: Roles.viewer,

  // anomalies + alerts (read)
  listAnomalies: Roles.viewer,
  listAlerts: Roles.viewer,
  getAlert: Roles.viewer,
  /** Anomaly source: viewer; audit/journal enforced admin inside handler */
  queryLogs: Roles.viewer,

  /** Live process table (Linux /proc) */
  listProcesses: Roles.viewer,

  // alerts / thresholds (write)
  setAlertConfig: Roles.operator,
  ackAlert: Roles.operator,
  silenceAlert: Roles.operator,

  // jobs (on-demand collection / maintenance)
  listJobs: Roles.viewer,
  runJob: Roles.operator,
  cancelJob: Roles.operator,

  // HyperDB peer links / db info
  getDbInfo: Roles.viewer,
  listPeerLinks: Roles.viewer,
  linkPeer: Roles.admin,
  unlinkPeer: Roles.admin,

  // Data Manager — retention + storage
  getStorageInfo: Roles.viewer,
  getRetentionConfig: Roles.viewer,
  setRetentionConfig: Roles.admin,
  pruneHistory: Roles.admin,

  // parent / fleet aggregation
  getFleetHealth: Roles.viewer,
  listChildPeers: Roles.viewer,

  // admin / fleet
  mintInvite: Roles.admin,
  listPeers: Roles.admin,
  revokePeer: Roles.admin,
  exportSnapshot: Roles.admin,
})

/**
 * String method names for typed client calls.
 */
export const Methods = Object.freeze(
  Object.fromEntries(Object.keys(MethodRoles).map((k) => [k, k]))
)

/**
 * Server → client push event names (protomux-rpc events).
 */
export const Pushes = Object.freeze({
  metrics: 'push:metrics',
  anomaly: 'push:anomaly',
  alert: 'push:alert',
  health: 'push:health',
  job: 'push:job',
  system: 'push:system',
})

/**
 * Map push channel → UI event type.
 */
export const PushToType = Object.freeze({
  [Pushes.metrics]: 'metrics',
  [Pushes.anomaly]: 'anomaly',
  [Pushes.alert]: 'alert',
  [Pushes.health]: 'health',
  [Pushes.job]: 'job',
  [Pushes.system]: 'system',
})

/** Methods treated as hot-path (skip heavy audit / schema). */
export const HotMethods = Object.freeze(
  new Set([
    Methods.ping,
    Methods.queryData,
    Methods.subscribeMetrics,
    Methods.unsubscribeMetrics,
    Methods.getAllMetrics,
    Methods.listProcesses,
    Methods.getHostSnapshot,
    Methods.searchCharts,
    Methods.summarizeChart,
    Methods.investigateHost,
    Methods.hotMetrics,
    Methods.relatedCharts,
    Methods.compareChartWindows,
    Methods.summarizeCharts,
  ])
)