import type { DisplayName, LocalSymbol, RuleContext, SourceDocument } from '../contract'
import type { CodeReaderRegistry } from '../registry'
import type { TreeSitterRuntime } from '../runtime'
import type { DocumentMessage } from './messages'
import { fileAttributes, mergeAttributeNames } from '../attributes'
import { readBlockViews } from '../blockView'
import { commandRuleLookup } from '../commandRules'
import { markEntryBlocks } from '../entries/entryMarks'
import { ruleAttributeNames } from '../libraryRules'

/** 生成预览数据要读的那点文档信息（TextDocument 的子集）。 */
export interface DocumentSnapshot {
  languageId: string
  version: number
  getText: () => string
  /** 这份文件是项目写明的入口时，预览里名字对上的块标成入口（见 entries/entryPoints.ts） */
  entryNames?: readonly string[]
}

/** 发给预览的文档，和这份源码里起了中文名的定义（扩展端接着找用到它们的各处）、语言插件自己认得出的名字（LocalSymbol）。 */
export interface DocumentRead {
  message: DocumentMessage
  displayNames: DisplayName[]
  symbols: LocalSymbol[]
}

/**
 * 当前文档 → 发给预览的 document 消息；语言不支持或解析失败时带 error，blocks 为空。库规则出错不算失败，交给 report 记下；
 * 规则查名字的定义时问 lookup（RuleContext.lookup），翻译插件问调用的名字定义成哪种块时问 calleeKind（SourceDocument.calleeKind）。
 * 筛选属性和值的名字先取翻译插件的，没给的再取库规则的（LibraryRule.attributeNames）。
 * 入口文件里名字对上的块，概念列表的第一个换成入口（markEntryBlocks）。
 */
export async function documentMessage(
  document: DocumentSnapshot,
  registry: Pick<CodeReaderRegistry, 'languageFor' | 'translatorsFor' | 'selectedTranslator' | 'rulesFor' | 'commandRulesFor'>,
  runtime: Pick<TreeSitterRuntime, 'parse'>,
  report: (message: string) => void,
  lookup?: RuleContext['lookup'],
  calleeKind?: SourceDocument['calleeKind'],
): Promise<DocumentRead> {
  const { languageId, version } = document
  const source = document.getText()
  const translator = registry.selectedTranslator(languageId)
  const message: DocumentMessage = {
    type: 'document',
    version,
    languageId,
    blocks: [],
    attributes: [],
    translators: registry.translatorsFor(languageId).map(({ id, label }) => ({ id, label })),
    translatorId: translator?.id ?? '',
    names: [],
  }
  const adapter = registry.languageFor(languageId)
  if (!adapter)
    return { message: { ...message, error: `代码阅读还不支持「${languageId}」这种语言` }, displayNames: [], symbols: [] }
  try {
    const rules = registry.rulesFor(languageId)
    const { blocks, displayNames, symbols } = await readBlockViews(runtime, adapter, translator, languageId, source, {
      rules: { rules, report, lookup },
      calleeKind,
      commandRule: commandRuleLookup(registry.commandRulesFor(languageId), report),
      embedded: (embeddedId) => {
        const embeddedAdapter = registry.languageFor(embeddedId)
        return embeddedAdapter && {
          adapter: embeddedAdapter,
          translator: registry.selectedTranslator(embeddedId),
          commandRule: commandRuleLookup(registry.commandRulesFor(embeddedId), report),
        }
      },
    })
    const names = mergeAttributeNames([translator?.attributeNames, ...ruleAttributeNames(rules, translator?.displayLanguage, report)])
    return { message: { ...message, blocks: markEntryBlocks(blocks, source, document.entryNames ?? []), attributes: fileAttributes(blocks, names) }, displayNames, symbols }
  }
  catch (err) {
    return { message: { ...message, error: err instanceof Error ? err.message : String(err) }, displayNames: [], symbols: [] }
  }
}