// Render Snapshot 纯物化（Plan 4 Task 2，ADR-011、V2 spec §9.2、快线 §8.4）：
// 从 published 修订 + route_registry + media ready 集合物化冻结六文件
// （RENDER_SNAPSHOT_FILES 契约清单），**db 只读、零写入**（磁盘仅做副本存在性探测）。
// 构建编排（job 状态机/落盘/快照行）在 build.service.ts——本文件只负责"读出什么"。
//
// 发布语义（ADR-010）：只读 entry_locales.published_revision_id 指向的修订——current
// 分叉（发布后再导入产新修订）不影响本快照；发布后的人工/导入变化须重新 publish +
// 新 build 才进产物。published 指针悬空（目标修订行缺席，指针列无 FK）→ issue 如实
// 报告（§7.6 禁静默），该条目不进 content.json。
//
// bodyHtml URL 重写（计划 Task 2 钉死匹配键）：正则提取 src/href → 剥 host 取 path →
// 与 media ready 集合的 public_path / source_url 路径段**双源**比对（覆盖绝对/根相对/
// 协议相对变体与查询串）→ 命中改写为根相对 public_path；未命中保留原样 + unresolved
// 计数（render-manifest.urlRewrite——内链 miss 是常态统计不是错误；外域热链同理）。
// data:/纯片段/相对形态无路径可比对，原样越过不计（与 media-writer 的 data: 口径一致）。
//
// canonical JSON 确定性：六文件全部以 canonicalJson（键递归字典序、无空白）+ 换行落盘
// ——文件字节（含尾换行）即哈希输入（content/route/asset 三哈希 = 各自**文件字节**的
// sha256——哈希链与落盘文件互证），同输入（含 generatedAt 时点参数）两次物化字节一致。
// 集合排序在 JS 侧钉死（UTF-16
// 序，不依赖 PG collation）：内容按 (typeKey, slug, locale, contentId)、分类按 (key,
// objectType)、term 按 (sourceId, slug, id)、路由按 (routePath, queryKey nulls-first,
// host)、资产按 publicPath。
//
// 媒体实体路径解析（assets.json 的 copyPath）：register 快照 metadata.storageRoot +
// storage_path（content-addressed 副本）为首选，仓库存储根同路径次之，storage/incoming
// 按清单文件名兜底（真实数据扁平 GUID 命名，basename 即唯一键）；全部缺席 → issue
// 如实报告（复制防线在 Task 5 构建管线，此处不静默也不阻断）。
import { createHash } from 'node:crypto'
import { existsSync } from 'node:fs'
import { basename, dirname, join, resolve } from 'node:path'
import { fileURLToPath } from 'node:url'
import { and, desc, eq, inArray, isNotNull, ne } from 'drizzle-orm'
import type { NodePgDatabase } from 'drizzle-orm/node-postgres'
import {
  ADAPTER_VERSION,
  MAPPING_VERSION,
  PARSER_VERSION,
  SANITIZER_VERSION,
} from '@sf/adapter-wp'
import { RENDER_SNAPSHOT_VERSION, type RenderSnapshotFile } from '@sf/contracts'
import { canonicalJson } from '../../common/canonical.js'
import {
  contentEntries,
  contentRevisions,
  contentTerms,
  entryLocales,
  mediaAssets,
  mediaUsages,
  routeRegistry,
  siteConfigRevisions,
  sourceSnapshots,
  taxonomies,
  terms,
} from '../../db/schema.js'
import type * as schema from '../../db/schema.js'

/** 本文件位于 <repo>/apps/api/src/modules/build/ → 上五级是仓库根 */
const REPO_ROOT = resolve(dirname(fileURLToPath(import.meta.url)), '../../../../..')

/** 读取面：db 池与事务句柄都满足（build.service 以 repeatable read 事务传入） */
export type SnapshotDb = NodePgDatabase<typeof schema>
export type SnapshotReader = Pick<SnapshotDb, 'select'>

// ---- URL 重写（纯函数，测试直测） ----

/** media ready 集合的最小匹配面（public_path 与 source_url 双源建键） */
export interface MediaPathSource {
  publicPath: string
  sourceUrl: string
}

/**
 * URL → 可比对路径：剥 host（绝对/协议相对）、剥查询/锚、保证首斜杠；
 * data:/纯片段/相对形态返回 null（无路径可比对，原样越过）。
 */
function comparablePathOf(raw: string): string | null {
  if (raw === '' || raw.startsWith('data:')) return null
  let rest: string
  if (raw.startsWith('//')) {
    const pathStart = raw.indexOf('/', 2)
    if (pathStart === -1) return null // //host 无路径证据——不比对（'/' 会误伤首页）
    rest = raw.slice(pathStart)
  } else {
    const abs = /^https?:\/\/[^/]+(.*)$/i.exec(raw)
    if (abs !== null) {
      rest = abs[1] === '' ? '/' : abs[1]!
    } else if (raw.startsWith('/')) {
      rest = raw
    } else {
      return null
    }
  }
  const cut = rest.search(/[?#]/)
  const path = cut === -1 ? rest : rest.slice(0, cut)
  return path === '' ? '/' : path
}

/**
 * media ready 路径索引：path（public_path 本形 + source_url 剥 host 的 path 段）→
 * 该资产的 public_path（命中改写目标）。同 path 双源冲突时先登记者胜（register 的
 * public_path 唯一键保证本形不冲突；跨源同 path 是数据面事实，任一命中即本地化）。
 */
export function buildMediaPathIndex(assets: MediaPathSource[]): Map<string, string> {
  const index = new Map<string, string>()
  for (const a of assets) {
    index.set(a.publicPath, a.publicPath)
    const src = comparablePathOf(a.sourceUrl)
    if (src !== null && !index.has(src)) index.set(src, a.publicPath)
  }
  return index
}

/** 重写统计（入 render-manifest.urlRewrite 与 build 报告 issues 面） */
export interface RewriteStats {
  /** 命中 ready 集合的引用数（含已是根相对形态的幂等命中） */
  rewritten: number
  /** 有路径可比对但未命中 ready 集合的引用数（保留原样） */
  unresolved: number
}

/**
 * bodyHtml 的 src/href URL 重写（正则提取——清洗信任链上游已保证属性形态规整；
 * 门禁期的 HTML 解析复用清洗管线是 Task 6 职责，此处不引入解析器依赖）。
 * 属性名边界锚定（审查 Fix 5）：前缀必须是空白或串首——`data-src`/`data-href`
 * 等连字属性不匹配不卷入（\b 会把 data-src 的 '-s' 交界误判为词边界；懒加载
 * 属性的改写是渲染域决策，不是快照域义务）。
 * 只替换属性值本身，引号/空白原样保留；命中值与原值相等时计数但零改写。
 */
export function rewriteBodyHtml(html: string, index: Map<string, string>): { html: string; stats: RewriteStats } {
  const stats: RewriteStats = { rewritten: 0, unresolved: 0 }
  const ATTR_RE = /(^|\s)(src|href)\s*=\s*(["'])([^"']*)\3/gi
  const out = html.replace(ATTR_RE, (full, _prefix: string, _attr: string, quote: string, value: string) => {
    const path = comparablePathOf(value)
    if (path === null) return full
    const hit = index.get(path)
    if (hit === undefined) {
      stats.unresolved++
      return full
    }
    stats.rewritten++
    if (hit === value) return full
    // match 尾部 = value + 收引号——只换值，保留原引号与属性的原始空白
    return `${full.slice(0, full.length - value.length - 1)}${hit}${quote}`
  })
  return { html: out, stats }
}

// ---- 物化 ----

/** 六文件的 canonical JSON 字符串（含尾换行——落盘字节即哈希输入 + '\n'） */
export type RenderSnapshotFileContents = Record<RenderSnapshotFile, string>

export interface MaterializeInput {
  siteId: string
  /** 快照生成时点（ISO 字符串）——render-manifest.generatedAt；同输入 + 同时点 → 字节一致 */
  generatedAt: string
}

export interface MaterializeResult {
  files: RenderSnapshotFileContents
  sourceHashes: {
    content: string
    route: string
    asset: string
  }
  counts: {
    contents: number
    taxonomies: number
    routes: number
    assets: number
  }
  urlRewrite: RewriteStats
  /** 物化期如实报告的问题（published 悬空/媒体副本缺席/不可服务路由形态）——进 build 报告 */
  issues: string[]
  /** site.json 来源的 config 修订（build_input_snapshots.site_config_revision_id 落值） */
  siteConfigRevisionId: string
}

/** UTF-16 字典序比较器（与 canonicalJson 键排序同语义——钉死不依赖 PG collation） */
function cmp(a: string, b: string): number {
  return a < b ? -1 : a > b ? 1 : 0
}
function cmpNull(a: string | null, b: string | null): number {
  if (a === null && b === null) return 0
  if (a === null) return -1
  if (b === null) return 1
  return cmp(a, b)
}

/** 三哈希的单一算法来源：sha256(文件字节)——canonicalJson + 尾换行后散列（与落盘文件互证） */
function hashOf(payload: unknown): string {
  return createHash('sha256').update(`${canonicalJson(payload)}\n`).digest('hex')
}

/** 仓库存储根的 incoming 媒体兜底目录（真实数据：storage/incoming/<目录>/<扁平 GUID 文件>） */
const REPO_STORAGE = join(REPO_ROOT, 'storage')

/**
 * 物化冻结 Render Snapshot 六文件（纯读 + 副本存在性探测）。
 * 前置不变量：站点已有 published 指针与 config 修订（build.service 建行前检查；
 * 直接调用方破坏不变量时以明错拒绝，不产残缺快照）。
 */
export async function materializeRenderSnapshot(
  db: SnapshotReader,
  input: MaterializeInput,
): Promise<MaterializeResult> {
  const issues: string[] = []
  const urlRewrite: RewriteStats = { rewritten: 0, unresolved: 0 }

  // site.json：config 修订最新版（Task 1 首发布生成 v1——data={name,origin,locale,brand}）
  const cfgRows = await db
    .select({ id: siteConfigRevisions.id, data: siteConfigRevisions.data })
    .from(siteConfigRevisions)
    .where(eq(siteConfigRevisions.siteId, input.siteId))
    .orderBy(desc(siteConfigRevisions.version))
    .limit(1)
  const config = cfgRows[0]
  if (config === undefined) {
    throw new Error(`站点 ${input.siteId} 无 site_config_revisions（publish 首版不变量破裂）——拒绝物化`)
  }

  // content.json：published 修订（leftJoin 显式暴露悬空指针——§7.6 禁静默）
  const localeRows = await db
    .select({
      contentId: contentEntries.id,
      typeKey: contentEntries.typeKey,
      locale: entryLocales.locale,
      localeSlug: entryLocales.slug,
      revisionId: contentRevisions.id,
      checksum: contentRevisions.checksum,
      data: contentRevisions.data,
    })
    .from(entryLocales)
    .innerJoin(contentEntries, eq(entryLocales.contentEntryId, contentEntries.id))
    .leftJoin(contentRevisions, eq(entryLocales.publishedRevisionId, contentRevisions.id))
    .where(and(eq(entryLocales.siteId, input.siteId), isNotNull(entryLocales.publishedRevisionId)))
  const published = localeRows.filter((r) => r.revisionId !== null)
  for (const row of localeRows) {
    if (row.revisionId === null) {
      issues.push(
        `published 指针悬空（entry=${row.contentId}/${row.locale}）：published_revision_id 指向的修订行缺席（指针列无 FK）——该条目不进 content.json`,
      )
    }
  }

  // media ready 集合：资产面（assets.json）与 URL 重写索引共用的单一查询
  const assetRows = await db
    .select({
      publicPath: mediaAssets.publicPath,
      sourceUrl: mediaAssets.sourceUrl,
      storagePath: mediaAssets.storagePath,
      sha256: mediaAssets.sha256,
      detectedMimeType: mediaAssets.detectedMimeType,
      byteSize: mediaAssets.byteSize,
      width: mediaAssets.width,
      height: mediaAssets.height,
      altText: mediaAssets.altText,
    })
    .from(mediaAssets)
    .where(and(eq(mediaAssets.siteId, input.siteId), eq(mediaAssets.status, 'ready')))
  assetRows.sort((a, b) => cmp(a.publicPath, b.publicPath))
  const mediaIndex = buildMediaPathIndex(assetRows)

  // published 修订的 media_usages 引用面（fieldPath → public_path；content.json 的 media 块）。
  // 确定性（审查 Fix 2）：fieldPath/publicPath 双键 orderBy 钉死 first-wins 的"首"——
  // 同 fieldPath 多资产引用（PK 是 资产×修订×fieldPath，跨资产可重）时取字典序首位，
  // 其余丢弃并记 issue（§7.6 禁静默）；只 join ready 资产（media 块只呈现可服务引用，
  // 审查 Fix 6）——非 ready 资产的残留引用单独查出版 issue，不进块。
  const publishedIds = published.map((r) => r.revisionId!)
  const usageMap = new Map<string, Map<string, string>>()
  if (publishedIds.length > 0) {
    const usages = await db
      .select({
        contentRevisionId: mediaUsages.contentRevisionId,
        fieldPath: mediaUsages.fieldPath,
        publicPath: mediaAssets.publicPath,
      })
      .from(mediaUsages)
      .innerJoin(mediaAssets, eq(mediaUsages.mediaAssetId, mediaAssets.id))
      .where(
        and(
          eq(mediaUsages.siteId, input.siteId),
          inArray(mediaUsages.contentRevisionId, publishedIds),
          eq(mediaAssets.status, 'ready'),
        ),
      )
      .orderBy(mediaUsages.fieldPath, mediaAssets.publicPath)
    for (const u of usages) {
      let byField = usageMap.get(u.contentRevisionId)
      if (byField === undefined) {
        byField = new Map()
        usageMap.set(u.contentRevisionId, byField)
      }
      const first = byField.get(u.fieldPath)
      if (first === undefined) {
        byField.set(u.fieldPath, u.publicPath)
      } else if (first !== u.publicPath) {
        issues.push(
          `同 fieldPath 多资产引用（revision=${u.contentRevisionId} fieldPath=${u.fieldPath}）：first-wins 取 ${first}，丢弃 ${u.publicPath}`,
        )
      }
    }
    // 非 ready 资产的残留引用（登记后状态翻转等数据面事实）：不进 media 块，如实记 issue
    const nonReady = await db
      .select({
        contentRevisionId: mediaUsages.contentRevisionId,
        fieldPath: mediaUsages.fieldPath,
        publicPath: mediaAssets.publicPath,
        status: mediaAssets.status,
      })
      .from(mediaUsages)
      .innerJoin(mediaAssets, eq(mediaUsages.mediaAssetId, mediaAssets.id))
      .where(
        and(
          eq(mediaUsages.siteId, input.siteId),
          inArray(mediaUsages.contentRevisionId, publishedIds),
          ne(mediaAssets.status, 'ready'),
        ),
      )
    for (const u of nonReady) {
      issues.push(
        `media 引用非 ready 资产（revision=${u.contentRevisionId} fieldPath=${u.fieldPath} public_path=${u.publicPath} status=${u.status}）——该引用不进 content.json media 块`,
      )
    }
  }

  const contentPayload = published.map((row) => {
    const data = (row.data ?? {}) as Record<string, unknown>
    let entryData = data
    if (typeof data.bodyHtml === 'string') {
      const r = rewriteBodyHtml(data.bodyHtml, mediaIndex)
      urlRewrite.rewritten += r.stats.rewritten
      urlRewrite.unresolved += r.stats.unresolved
      entryData = { ...data, bodyHtml: r.html }
    }
    // slug 以修订 data.slug（发布时点冻结值）为准，缺席回退 entry_locales.slug（current 跟随面）
    const slug = typeof data.slug === 'string' && data.slug !== '' ? data.slug : row.localeSlug
    const media = usageMap.get(row.revisionId!)
    const entry: Record<string, unknown> = {
      contentId: row.contentId,
      typeKey: row.typeKey,
      locale: row.locale,
      slug,
      data: entryData,
      revisionId: row.revisionId,
      checksum: row.checksum,
    }
    if (media !== undefined && media.size > 0) {
      entry.media = Object.fromEntries([...media.entries()].sort(([a], [b]) => cmp(a, b)))
    }
    return entry
  })
  contentPayload.sort((a, b) =>
    cmp(a.typeKey as string, b.typeKey as string)
      || cmp(a.slug as string, b.slug as string)
      || cmp(a.locale as string, b.locale as string)
      || cmp(a.contentId as string, b.contentId as string),
  )

  // taxonomies.json：taxonomies × terms 全量 + content_terms 关联（auto: 自建行 source_id 原样）
  const taxonomyRows = await db
    .select({
      id: taxonomies.id,
      key: taxonomies.key,
      objectType: taxonomies.objectType,
      publicBasePath: taxonomies.publicBasePath,
    })
    .from(taxonomies)
    .where(eq(taxonomies.siteId, input.siteId))
  const termRows = await db
    .select({
      id: terms.id,
      taxonomyId: terms.taxonomyId,
      sourceId: terms.sourceId,
      slug: terms.slug,
      name: terms.name,
      parentTermId: terms.parentTermId,
      data: terms.data,
    })
    .from(terms)
    .where(eq(terms.siteId, input.siteId))
  const relationRows = await db
    .select({ termId: contentTerms.termId, contentEntryId: contentTerms.contentEntryId })
    .from(contentTerms)
    .where(eq(contentTerms.siteId, input.siteId))
  const entriesByTerm = new Map<string, string[]>()
  for (const rel of relationRows) {
    const list = entriesByTerm.get(rel.termId) ?? []
    list.push(rel.contentEntryId)
    entriesByTerm.set(rel.termId, list)
  }
  const termsByTaxonomy = new Map<string, typeof termRows>()
  for (const t of termRows) {
    const list = termsByTaxonomy.get(t.taxonomyId) ?? []
    list.push(t)
    termsByTaxonomy.set(t.taxonomyId, list)
  }
  const taxonomiesPayload = taxonomyRows.map((tax) => {
    const group = (termsByTaxonomy.get(tax.id) ?? []).map((t) => ({
      id: t.id,
      sourceId: t.sourceId,
      slug: t.slug,
      name: t.name,
      parentTermId: t.parentTermId,
      data: (t.data ?? {}) as Record<string, unknown>,
      contentEntryIds: (entriesByTerm.get(t.id) ?? []).sort(cmp),
    }))
    group.sort((a, b) => cmp(a.sourceId, b.sourceId) || cmp(a.slug, b.slug) || cmp(a.id, b.id))
    return { key: tax.key, objectType: tax.objectType, publicBasePath: tax.publicBasePath, terms: group }
  })
  taxonomiesPayload.sort((a, b) => cmp(a.key, b.key) || cmp(a.objectType, b.objectType))

  // routes.json：可服务路由形态（html/asset/redirect/gone）；dynamic/unresolved 不进产物
  const routeRows = await db
    .select({
      host: routeRegistry.host,
      routePath: routeRegistry.routePath,
      routeKind: routeRegistry.routeKind,
      queryPolicy: routeRegistry.queryPolicy,
      queryKey: routeRegistry.queryKey,
      targetStatus: routeRegistry.targetStatus,
      targetContentId: routeRegistry.targetContentId,
      targetFile: routeRegistry.targetFile,
      redirectStatus: routeRegistry.redirectStatus,
      redirectLocation: routeRegistry.redirectLocation,
      indexable: routeRegistry.indexable,
      priority: routeRegistry.priority,
      verificationStatus: routeRegistry.verificationStatus,
    })
    .from(routeRegistry)
    .where(eq(routeRegistry.siteId, input.siteId))
  const SERVICABLE = new Set(['html', 'asset', 'redirect', 'gone'])
  const unservicable = routeRows.filter((r) => !SERVICABLE.has(r.routeKind))
  if (unservicable.length > 0) {
    issues.push(
      `路由表含 ${unservicable.length} 条不可服务形态（dynamic/unresolved）——不进 routes.json（处置是 SP3+ 查询路由域）`,
    )
  }
  const routesPayload = routeRows.filter((r) => SERVICABLE.has(r.routeKind))
  routesPayload.sort(
    (a, b) => cmp(a.routePath, b.routePath) || cmpNull(a.queryKey, b.queryKey) || cmp(a.host, b.host),
  )

  // assets.json：ready 资产 + 实体副本路径解析（content-addressed 首选 → 仓库存储根 → incoming 兜底）
  const bundleRows = await db
    .select({ metadata: sourceSnapshots.metadata })
    .from(sourceSnapshots)
    .where(and(eq(sourceSnapshots.siteId, input.siteId), eq(sourceSnapshots.kind, 'media_bundle')))
    .orderBy(desc(sourceSnapshots.capturedAt), desc(sourceSnapshots.createdAt))
    .limit(1)
  const bundleRootRaw = bundleRows[0]?.metadata as { storageRoot?: unknown } | undefined
  const bundleRoot = typeof bundleRootRaw?.storageRoot === 'string' ? bundleRootRaw.storageRoot : null

  const assetsPayload = assetRows.map((a) => {
    const candidates: string[] = []
    if (bundleRoot !== null && bundleRoot !== '') candidates.push(join(bundleRoot, a.storagePath))
    const repoCopy = join(REPO_STORAGE, a.storagePath)
    candidates.push(repoCopy)
    // incoming 兜底：清单文件名（真实数据扁平 GUID 命名，basename 唯一）
    candidates.push(join(REPO_STORAGE, 'incoming', basename(a.storagePath)))
    let copyPath = candidates[0] ?? repoCopy
    for (const c of candidates) {
      if (existsSync(c)) {
        copyPath = c
        break
      }
    }
    if (!existsSync(copyPath)) {
      issues.push(
        `媒体副本缺席（public_path=${a.publicPath}）：候选 ${candidates.join(' ; ')} 均不存在——assets.json 记录首选路径，复制阶段（Task 5 管线）将失败`,
      )
    }
    return {
      publicPath: a.publicPath,
      storagePath: a.storagePath,
      copyPath,
      sha256: a.sha256,
      detectedMimeType: a.detectedMimeType,
      byteSize: a.byteSize,
      width: a.width,
      height: a.height,
      altText: a.altText,
    }
  })

  // 三哈希（各文件 canonicalJson 的 sha256——字节可复算）+ render-manifest 汇聚
  const sourceHashes = {
    content: hashOf(contentPayload),
    route: hashOf(routesPayload),
    asset: hashOf(assetsPayload),
  }
  const counts = {
    contents: contentPayload.length,
    taxonomies: taxonomiesPayload.length,
    routes: routesPayload.length,
    assets: assetsPayload.length,
  }
  const manifestPayload = {
    renderSnapshotVersion: RENDER_SNAPSHOT_VERSION,
    versions: {
      adapter: ADAPTER_VERSION,
      mapping: MAPPING_VERSION,
      sanitizer: SANITIZER_VERSION,
      parser: PARSER_VERSION,
    },
    counts,
    sourceHashes,
    urlRewrite,
    generatedAt: input.generatedAt,
  }

  const file = (payload: unknown): string => `${canonicalJson(payload)}\n`
  const files: RenderSnapshotFileContents = {
    'site.json': file(config.data),
    'content.json': file(contentPayload),
    'taxonomies.json': file(taxonomiesPayload),
    'routes.json': file(routesPayload),
    'assets.json': file(assetsPayload),
    'render-manifest.json': file(manifestPayload),
  }
  return { files, sourceHashes, counts, urlRewrite, issues, siteConfigRevisionId: config.id }
}