/**
 * CompactorRole - Context compaction worker
 * Summaries/artifacts only — no filesystem writes.
 *
 * @module packages/workers/src/roles/CompactorRole
 */

import { WorkerRuntime } from '../WorkerRuntime.js'

export interface CompactorResult {
  status: 'compacted' | 'skipped' | 'blocked'
  summary_content: string
  tokens_freed: number
  compacted_layers: string[]
}

export class CompactorRole {
  private runtime: WorkerRuntime

  constructor(runtime: WorkerRuntime) {
    this.runtime = runtime
  }

  async run(compact_spec: { task_id: string; current_tokens: number; threshold: number }): Promise<CompactorResult> {
    const result: CompactorResult = {
      status: 'skipped',
      summary_content: '',
      tokens_freed: 0,
      compacted_layers: []
    }

    try {
      this.runtime.emit('compaction.started', { task_id: compact_spec.task_id })

      // Check if compaction is needed
      if (compact_spec.current_tokens < compact_spec.threshold) {
        result.status = 'skipped'
        result.summary_content = `Tokens (${compact_spec.current_tokens}) below threshold (${compact_spec.threshold})`
        return result
      }

      // Generate summary (stub)
      result.summary_content = '# Compaction Summary\n\nStub implementation — full compaction logic pending.'
      result.tokens_freed = compact_spec.current_tokens - Math.floor(compact_spec.current_tokens * 0.6)
      result.compacted_layers = ['conversation', 'tool_output']
      result.status = 'compacted'

      this.runtime.checkpoint('compaction_completed', { task_id: compact_spec.task_id })
      return result

    } catch (error) {
      result.status = 'blocked'
      result.summary_content = error instanceof Error ? error.message : String(error)
      return result
    }
  }
}
