import fs from 'fs'
import path from 'path'
import ts from 'typescript'
import { createEncodedSourceFile } from './createEncodedSourceFile'
import { transformSource } from './transformSource'

const visit =
  (context: ts.TransformationContext, tagName: string) =>
  (node: ts.Node): ts.Node => {
    if (ts.isJsxOpeningElement(node) || ts.isJsxSelfClosingElement(node)) {
      if (node.tagName.getText() === tagName) {
        const newAttributes = node.attributes.properties.map((attr) => {
          if (ts.isJsxAttribute(attr) && attr.name.getText() === 'topping') {
            return ts.factory.updateJsxAttribute(
              attr,
              attr.name,
              ts.factory.createStringLiteral('jam'),
            )
          }
          return attr
        })
        if (ts.isJsxSelfClosingElement(node)) {
          return ts.factory.updateJsxSelfClosingElement(
            node,
            node.tagName,
            node.typeArguments,
            ts.factory.createJsxAttributes(newAttributes),
          )
        }
      }
    }
    return ts.visitEachChild(node, visit(context, tagName), context)
  }

describe('transformSource()', () => {
  it('updates the value of Pancakes topping to jam', () => {
    const filePath = path.resolve(path.join(__dirname, './__fixtures__/KaioComponent.tsx'))
    const fileContent = fs.readFileSync(filePath, 'utf8')
    const sourceFile = createEncodedSourceFile(filePath, fileContent)
    const mockTransformer =
      (tagName: string): ts.TransformerFactory<ts.SourceFile> =>
      (context) =>
      (rootNode) =>
        ts.visitNode(rootNode, visit(context, tagName)) as ts.SourceFile

    const transformed = transformSource({
      sourceFile,
      transformers: [mockTransformer('Pancakes')],
    })

    expect(transformed).toMatchSnapshot()
  })
})