codegen-plugin.ts

import type { Plugin } from 'rollup'
import traverse from '@babel/traverse'
import * as t from '@babel/types'
import { parse } from '@babel/parser'
import generate from '@babel/generator'
import { buildSchema, parse as parseGql } from 'graphql'
import { ClientSideBaseVisitor } from '@graphql-codegen/visitor-plugin-common'
import * as queries from '../gql/graphql'

const gqlTagName = 'graphql'

const noopSchema = buildSchema('type Query { _: Int }')

export default function (): Plugin {
  const visitor = new ClientSideBaseVisitor(noopSchema, [], {}, {})

  return {
    name: 'codegen-plugin',
    transform (code, id) {
      if (!(id.endsWith('.ts') || id.endsWith('.vue'))) {
        return
      }
      const module = parse(code, {
        sourceType: 'module'
      })

      traverse(module, {
        ImportDeclaration (path) {
          const isGql = path.node.specifiers.find(it => it.type === 'ImportSpecifier' && it.imported.type === 'Identifier' && it.imported.name === 'graphql') !== undefined
          if (isGql) {
            path.remove()
          }
        },
        CallExpression (path) {
          if (path.node.callee.type !== 'Identifier' || path.node.callee.name !== gqlTagName) {
            return
          }
          const [argument] = path.node.arguments
          if (argument == null) {
            return
          }
          if (argument.type !== 'TemplateLiteral') {
            return
          }

          const [content] = argument.quasis
          const ast = parseGql(content.value.raw)

          const [firstDefinition] = ast.definitions

          if (firstDefinition.kind !== 'FragmentDefinition' && firstDefinition.kind !== 'OperationDefinition') {
            return
          }

          if (firstDefinition.name == null) {
            return
          }

          const operationOrFragmentName =
            firstDefinition.kind === 'OperationDefinition'
              ? visitor.getOperationVariableName(firstDefinition)
              : visitor.getFragmentVariableName(firstDefinition)

          // eslint-disable-next-line @typescript-eslint/no-explicit-any
          path.replaceWith(t.stringLiteral((queries as unknown as Record<string, queries.TypedDocumentString<any, any>>)[operationOrFragmentName].toString()))
        }
      })

      return generate(module, {}, code)
    }
  }
}