import type { FastifyPluginAsync } from "fastify"
import { appendEvent } from "../modules/events/service/events-service.js"
import {
  exportSystemDatabaseBackup,
  restoreSystemDatabaseBackup,
} from "../services/system-database-backup.js"

interface Dependencies {
  exportBackup: typeof exportSystemDatabaseBackup
  restoreBackup: typeof restoreSystemDatabaseBackup
  event: typeof appendEvent
}
export function createSystemDatabaseRoutes(deps: Dependencies): FastifyPluginAsync { return async (app) => {
  app.addContentTypeParser(
    "application/octet-stream",
    { parseAs: "buffer", bodyLimit: 512 * 1024 * 1024 },
    (_req, body, done) => {
      done(null, body)
    },
  )

  app.get("/system/database/backup", async (_req, reply) => {
    try {
      const { filename, buffer, ...warnings } = await deps.exportBackup()
      let eventError: string | undefined
      try {
        await deps.event({
        level: "info",
        eventType: "system.database.backup",
        sourceModule: "system",
        title: "Создан бэкап базы приложения",
        message: filename,
        entityType: "system_database",
        entityId: filename,
        payload: {
          filename,
          sizeBytes: buffer.length,
        },
      })
      } catch { eventError = "Не удалось записать событие резервного копирования" }
      const outcome = { ...warnings, ...(eventError ? { eventError } : {}) }
      reply.header("X-System-Database-Outcome", encodeURIComponent(JSON.stringify(outcome)))
      reply.header("Content-Type", "application/octet-stream")
      reply.header("Content-Disposition", `attachment; filename="${filename}"`)
      return reply.send(buffer)
    } catch (err) {
      const message = err instanceof Error ? err.message : String(err)
      return reply.status(message.includes("уже выполняется") ? 409 : 500).send({ error: message })
    }
  })

  app.post("/system/database/restore", async (req, reply) => {
    const body = req.body
    if (!Buffer.isBuffer(body) || body.length === 0) {
      return reply.status(400).send({ error: "Ожидается тело запроса с файлом pg_dump (custom, PGDMP)" })
    }
    try {
      const outcome = await deps.restoreBackup(body)
      let eventError: string | undefined
      try {
        await deps.event({
        level: "warning",
        eventType: "system.database.restore",
        sourceModule: "system",
        title: "Восстановлена база приложения",
        message: "Данные PostgreSQL заменены из загруженного дампа",
        entityType: "system_database",
        entityId: "restore",
        payload: {
          sizeBytes: body.length,
        },
      })
      } catch { eventError = "Не удалось записать событие восстановления" }
      return reply.send({ ok: true, ...outcome, ...(eventError ? { eventError } : {}) })
    } catch (err) {
      const message = err instanceof Error ? err.message : String(err)
      const status = message.includes("уже выполняется") ? 409 : 400
      return reply.status(status).send({ error: message })
    }
  })
}

}

export default createSystemDatabaseRoutes({ exportBackup: exportSystemDatabaseBackup, restoreBackup: restoreSystemDatabaseBackup, event: appendEvent })