// turning a recorded flow draft into a maestro-compatible YAML file.
//
// this is separate from flow-session.ts, the draft store, because the two have
// different reach. every `do` verb writes a candidate into the store, so the
// store has to load wherever the CLI's runtime commands load, including inside
// a box shell running in workerd, where the `yaml` package does not load at
// all. YAML formatting and writing the file are the export step, and only
// `rnx flow` and `rnx maestro` ever reach it.

import { mkdirSync, writeFileSync } from 'node:fs'
import { dirname, resolve } from 'node:path'
import yaml from 'yaml'
import { validateFlowSteps } from './flow-file'
import { finalizeFlowSession, readFlowSession } from './flow-session'

export function exportFlowSession(outputPath?: string) {
  const state = readFlowSession()
  if (!state) return { active: false as const }

  const yamlText = `${yaml.stringify(state.steps).trimEnd()}\n`
  const issues = validateFlowSteps(state.steps)
  if (issues.length > 0) {
    return {
      active: true as const,
      valid: false as const,
      issues,
      yaml: yamlText,
      stepCount: state.steps.length,
      outputPath: null,
    }
  }

  let resolvedOutputPath: string | null = null
  if (outputPath) {
    resolvedOutputPath = resolve(outputPath)
    mkdirSync(dirname(resolvedOutputPath), { recursive: true })
    writeFileSync(resolvedOutputPath, yamlText)
  }

  return {
    active: true as const,
    valid: true as const,
    issues: [],
    yaml: yamlText,
    stepCount: state.steps.length,
    outputPath: resolvedOutputPath,
  }
}

export function endFlowSession(outputPath?: string) {
  const result = exportFlowSession(outputPath)
  if (!result.active) return result
  finalizeFlowSession()
  return result
}