import Ajv from 'ajv';
import { JsonSchema } from 'json-schema-spec-types';
import { invokeDiff } from './invoke-diff';

export interface DiffTestCase {
  description: string;
  examples: any[];
  focus?: boolean;
  input: {
    a: JsonSchema;
    b: JsonSchema;
  };
  output: {
    added: JsonSchema;
    removed: JsonSchema;
  };
}

export const registerDiffTestCases = (testCases: DiffTestCase[]) => {
  testCases.forEach(testCase => {
    const describeFn = testCase.focus ? fdescribe : describe;
    describeFn(testCase.description, () => {
      it('(source = A, destination = B)', async () => {
        const diffResult = await invokeDiff(testCase.input.a, testCase.input.b);

        expect(diffResult.addedJsonSchema).toEqual(testCase.output.added);
        expect(diffResult.removedJsonSchema).toEqual(testCase.output.removed);
      });

      it('(source = B, destination = A)', async () => {
        const diffResult = await invokeDiff(testCase.input.b, testCase.input.a);

        expect(diffResult.addedJsonSchema).toEqual(testCase.output.removed);
        expect(diffResult.removedJsonSchema).toEqual(testCase.output.added);
      });

      const ajv = new Ajv({ strict: false });
      const validateA = ajv.compile(testCase.input.a);
      const validateB = ajv.compile(testCase.input.b);
      const validateAdded = ajv.compile(testCase.output.added);
      const validateRemoved = ajv.compile(testCase.output.removed);

      testCase.examples.forEach(example => {
        const valueAsString = JSON.stringify(example);
        it(`example: ${valueAsString}`, () => {
          const acceptedByA = validateA(example);
          const acceptedByB = validateB(example);

          const acceptedByAdded = !acceptedByA && acceptedByB;
          const acceptedByRemoved = acceptedByA && !acceptedByB;

          expect(validateAdded(example)).toBe(
            acceptedByAdded,
            'when validating example against the added schema the result was inconsistent',
          );
          expect(validateRemoved(example)).toBe(
            acceptedByRemoved,
            'when validating example against the removed schema the result was inconsistent',
          );
        });
      });
    });
  });
};