import db from '@adonisjs/lucid/services/db'
import type { EdgeBatch } from '#lib/edge/index'
import ChunkPartitions from '#services/chunk_partitions'

export class StaleBatch extends Error {}

export interface StoredBatch {
  releases: number
  newReleases: number
  candidates: number
  fragments: number
}

/**
 * Stores one batch of a leased range (REBUILD.md, parts 3–7), in one
 * transaction: release aggregates in the catalog, one chunk per release,
 * probe candidates, rule counts and samples, edge fragments, and the
 * range's resume point. A batch that doesn't start at the resume point was
 * sent twice or too late, and is refused (StaleBatch), so the sums stay right.
 */
class BatchStore {
  async store(rangeId: number, nodeId: number, batch: EdgeBatch): Promise<StoredBatch> {
    await ChunkPartitions.ensure()
    return db.transaction(async (trx) => {
      const range = await trx.from('ranges').where('id', rangeId).forUpdate().first()
      if (!range || range.status !== 'leased' || Number(range.node_id) !== nodeId) throw new StaleBatch(`Range ${rangeId} is not leased to this node`)
      if (Number(range.next_id) !== batch.from) throw new StaleBatch(`Range ${rangeId} is at ${range.next_id}, the batch starts at ${batch.from}`)
      const result: StoredBatch = { releases: batch.releases.length, newReleases: 0, candidates: 0, fragments: batch.fragments.length }

      // Releases, sorted by key so concurrent batches lock them in the same order.
      const releases = [...batch.releases].sort((a, b) => a.key.localeCompare(b.key))
      const ids = new Map<string, number>()
      for (let i = 0; i < releases.length; i += 1000) {
        const chunk = releases.slice(i, i + 1000)
        const { rows } = await trx.rawQuery(
          `INSERT INTO releases (release_key, name, source, poster, groups, posted_at, file_total, files, segments, bytes, chunks, first_article, last_article, readable, has_par2)
           SELECT v.key, v.name, v.source, v.poster, v.groups, to_timestamp(v.posted_at / 1000.0), v.file_total, v.files, v.segments, v.bytes, 1, v.first_article, v.last_article, v.readable, v.has_par2
           FROM jsonb_to_recordset(?::jsonb) AS v(key text, name text, source text, poster text, groups jsonb, posted_at bigint, file_total int, files int, segments bigint, bytes bigint, first_article bigint, last_article bigint, readable boolean, has_par2 boolean)
           ON CONFLICT (release_key) DO UPDATE SET
             files = releases.files + excluded.files,
             segments = releases.segments + excluded.segments,
             bytes = releases.bytes + excluded.bytes,
             chunks = releases.chunks + 1,
             posted_at = least(releases.posted_at, excluded.posted_at),
             file_total = coalesce(releases.file_total, excluded.file_total),
             first_article = least(releases.first_article, excluded.first_article),
             last_article = greatest(releases.last_article, excluded.last_article),
             readable = releases.readable OR excluded.readable,
             has_par2 = releases.has_par2 OR excluded.has_par2,
             last_seen_at = now()
           RETURNING id, release_key, (xmax = 0) AS inserted`,
          [
            JSON.stringify(
              chunk.map((r) => ({
                key: r.key, name: r.name, source: r.source, poster: r.poster, groups: r.groups, posted_at: r.postedAt, file_total: r.fileTotal,
                files: r.files, segments: r.segments, bytes: r.bytes, first_article: r.firstArticle, last_article: r.lastArticle, readable: r.readable, has_par2: r.hasPar2,
              }))
            ),
          ]
        )
        for (const row of rows) {
          ids.set(row.release_key, Number(row.id))
          if (row.inserted) result.newReleases++
        }
      }

      // One write-once chunk per release.
      for (let i = 0; i < releases.length; i += 500) {
        const rows = releases.slice(i, i + 500).map((r) => ({
          release_id: ids.get(r.key)!,
          range_id: rangeId,
          batch_seq: batch.from,
          files: r.files,
          segments: r.segments,
          payload: r.payload,
        }))
        if (rows.length > 0) await trx.insertQuery().table('release_chunks').multiInsert(rows)
      }

      const candidates = batch.candidates.filter((c) => ids.has(c.releaseKey))
      for (let i = 0; i < candidates.length; i += 2000) {
        const rows = candidates.slice(i, i + 2000).map((c) => ({ release_id: ids.get(c.releaseKey)!, kind: c.kind, message_id: c.messageId, file: c.file }))
        const added = await trx.knexQuery().table('probe_candidates').insert(rows).onConflict(['release_id', 'kind', 'message_id']).ignore().returning('id')
        result.candidates += added.length
      }

      if (batch.counts.length > 0) {
        await trx.rawQuery(
          `INSERT INTO rule_counts (range_id, rule, key, articles, files)
           SELECT ?, v.rule, v.key, v.articles, v.files FROM jsonb_to_recordset(?::jsonb) AS v(rule text, key text, articles bigint, files bigint)
           ON CONFLICT (range_id, rule, key) DO UPDATE SET articles = rule_counts.articles + excluded.articles, files = rule_counts.files + excluded.files`,
          [rangeId, JSON.stringify(batch.counts)]
        )
      }

      for (const s of batch.samples) {
        await trx.insertQuery().table('rule_samples').insert({
          range_id: rangeId, rule: s.rule, rule_key: s.ruleKey, release_key: s.key, name: s.name, files: s.files, segments: s.segments, payload: s.payload,
        })
      }

      for (let i = 0; i < batch.fragments.length; i += 2000) {
        const rows = batch.fragments.slice(i, i + 2000).map((f) => ({ range_id: rangeId, file_key: f.fileKey, article_number: f.articleNumber, segment: JSON.stringify(f) }))
        await trx.insertQuery().table('fragments').multiInsert(rows)
      }

      await trx
        .from('ranges')
        .where('id', rangeId)
        .update({ next_id: batch.next, headers: db.raw('headers + ?', [batch.headers]), heartbeat_at: new Date() })
      return result
    })
  }
}

export default new BatchStore()