import { completeFromList } from '@codemirror/autocomplete'
import {
  javascript,
  javascriptLanguage,
  localCompletionSource,
  scopeCompletionSource,
  snippets
} from '@codemirror/lang-javascript'
import { nodeJsScope } from './nodeScope.js'

function extraScope(autoCompleteObject) {
  let data = autoCompleteObject
  if (typeof data === 'string') {
    try {
      data = JSON.parse(data)
    } catch {
      data = {}
    }
  }
  if (!data || typeof data !== 'object' || Array.isArray(data)) {
    return {}
  }
  return data
}

export function nodeScopeCompletionSource(autoCompleteObject) {
  return scopeCompletionSource({
    ...nodeJsScope,
    ...extraScope(autoCompleteObject)
  })
}

/**
 * Completions for mixed languages that mount `javascriptLanguage`
 * without `javascript()` (snippets + locals + Node globals).
 */
export function javascriptCompletionSources(autoCompleteObject) {
  return [
    completeFromList(snippets),
    localCompletionSource,
    nodeScopeCompletionSource(autoCompleteObject)
  ]
}

/**
 * JavaScript language support with Node.js globals, snippets, and
 * local-variable completion.
 * @param {{ autoCompleteObject?: object|string }} [options]
 */
export function javascriptLang(options = {}) {
  const { autoCompleteObject } = options
  return [
    javascript(),
    javascriptLanguage.data.of({
      autocomplete: nodeScopeCompletionSource(autoCompleteObject)
    })
  ]
}

export { nodeJsScope }