import { readdir, readFile } from "node:fs/promises"
import path from "node:path"

async function safeRead(filePath) {
  try {
    return await readFile(filePath, "utf8")
  } catch {
    return null
  }
}

export const FidelityCompaction = async ({ directory }) => {
  return {
    "experimental.session.compacting": async (_input, output) => {
      const baseFiles = [
        "README.md",
        "core/README.md",
        "core/memory/operational-memory.md",
        "core/integrations/memory-vault-model.md",
        "core/integrations/communication-model.md",
        "profiles/fidelity/profile.md",
        "agent-memory/README.md",
        "agent-memory/behavior/agent-behavior.md",
        "agent-memory/memory/promotion-rules.md",
        "agent-memory/memory/context-maintenance.md",
        "agent-memory/integrations/technical-verification.md",
        "agent-memory/workflows/workspace-model.md",
        "agent-memory/workflows/ai-to-ai-prompting.md",
        "project-knowledge/00-start/start-here.md",
        "project-knowledge/01-current/current-work.md",
        "project-knowledge/01-current/work-items.md",
        "project-knowledge/03-context/project.md",
        "project-knowledge/03-context/ios/index.md",
        "project-knowledge/03-context/ios/current-practices.md",
        "project-knowledge/03-context/ios/project-swift-guidance.md",
        "project-knowledge/03-context/systems/index.md",
        "project-knowledge/03-context/workstreams/index.md",
        "project-knowledge/03-context/process/communication.md",
        "project-knowledge/04-people/manager.md",
        "project-knowledge/04-people/index.md",
        "project-knowledge/05-decisions/rest-vs-graphql.md",
        "project-knowledge/05-decisions/discourse-handling.md",
      ]

      const sections = []

      for (const relPath of baseFiles) {
        const content = await safeRead(path.join(directory, relPath))
        if (content) {
          sections.push(`### ${relPath}\n${content.trim()}`)
        }
      }

      try {
        const logsDir = path.join(directory, "project-knowledge/06-daily")
        const logs = (await readdir(logsDir))
          .filter((name) => name.endsWith(".md"))
          .sort()
          .slice(-2)

        for (const logName of logs) {
          const content = await safeRead(path.join(logsDir, logName))
          if (content) {
            sections.push(`### project-knowledge/06-daily/${logName}\n${content.trim()}`)
          }
        }
      } catch {
        // No logs available yet.
      }

      if (sections.length > 0) {
        output.context.push(
          [
            "## AI Workspace Persistent Context",
            "Preserve this operational memory across compaction.",
            "If later messages introduced corrections or durable facts, prefer the corrected view over stale summaries.",
            "",
            sections.join("\n\n"),
          ].join("\n"),
        )
      }
    },
  }
}