/**
 * TaskLog Stream Definition
 *
 * Manages log entries for each task execution.
 * Uses sessionId as groupId for per-task log isolation.
 * Retains recent N entries for state recovery.
 *
 * @see Requirements 4.2, 4.6
 */

import { defineStream } from '@motia/core'
import { z } from 'zod'
import type { StepId } from './taskState'

// Log level enum
export const LogLevelSchema = z.enum(['INFO', 'WARN', 'ERROR'])
export type LogLevel = z.infer<typeof LogLevelSchema>

// Task log entry schema
export const TaskLogEntrySchema = z.object({
  sessionId: z.string(),
  stepId: z.string(), // StepId type
  ts: z.string(), // ISO timestamp
  level: LogLevelSchema,
  message: z.string(),
  seq: z.number(), // Log sequence number for ordering
})
export type TaskLogEntry = z.infer<typeof TaskLogEntrySchema>

// Maximum number of log entries to retain per task
export const MAX_LOG_ENTRIES = 1000

/**
 * Create a new log entry
 */
export function createLogEntry(
  sessionId: string,
  stepId: StepId,
  level: LogLevel,
  message: string,
  seq: number
): TaskLogEntry {
  return {
    sessionId,
    stepId,
    ts: new Date().toISOString(),
    level,
    message,
    seq,
  }
}

// Define the taskLog stream
export const taskLogStream = defineStream({
  name: 'taskLog',
  schema: TaskLogEntrySchema,
  persistence: {
    enabled: true,
    // Retain recent entries for state recovery
    maxEntries: MAX_LOG_ENTRIES,
  },
})