import {
  assert,
  expect,
} from 'chai';

import {
    GraphQLSchema,
    GraphQLObjectType,
    GraphQLString,
} from 'graphql';

// TODO use import, not require... help appreciated.
import * as express from 'express';
import * as bodyParser from 'body-parser';
// tslint:disable-next-line
const request = require('supertest-as-promised');

import { graphqlHTTP, ExpressApolloOptions, renderGraphiQL } from './expressApollo';
import * as GraphiQL from '../modules/renderGraphiQL';
import { OperationStore } from '../modules/operationStore';

const QueryType = new GraphQLObjectType({
    name: 'QueryType',
    fields: {
        testString: {
            type: GraphQLString,
            resolve() {
                return 'it works';
            },
        },
        testArgument: {
            type: GraphQLString,
            args: { echo: { type: GraphQLString } },
            resolve(root, { echo }) {
                return `hello ${echo}`;
            },
        },
    },
});

const MutationType = new GraphQLObjectType({
    name: 'MutationType',
    fields: {
        testMutation: {
            type: GraphQLString,
            args: { echo: { type: GraphQLString } },
            resolve(root, { echo }) {
                return `not really a mutation, but who cares: ${echo}`;
            },
        },
    },
});

const Schema = new GraphQLSchema({
    query: QueryType,
    mutation: MutationType,
});

export interface CreateAppOptions {
  excludeParser?: boolean;
  apolloOptions?: ExpressApolloOptions;
  graphiqlOptions?: GraphiQL.GraphiQLData;
}

export interface CreateAppFunc {
    (options?: CreateAppOptions): void;
}

export default (createWebApp: CreateAppFunc) => {

  // wrap the createWebApp function to set the schema by default for all tests
  let createApp: CreateAppFunc;
  createApp = (options) => {
    const opts = options || {};
    opts.apolloOptions = (!options || !options.apolloOptions) ? { schema: Schema } : options.apolloOptions;
    return createWebApp(opts);
  };

  describe('expressApollo', () => {
    describe('graphqlHTTP', () => {
       it('returns express middleware', () => {
          const middleware = graphqlHTTP({
              schema: Schema,
          });
          assert(typeof middleware === 'function');
      });
      it('throws error if called without schema', () => {
         expect(() => graphqlHTTP(undefined as ExpressApolloOptions)).to.throw('Apollo Server requires options.');
      });

      it('can be called with an options function', () => {
          const app = createApp();
          const expected = {
              testString: 'it works',
          };
          const req = request(app)
              .post('/graphql')
              .send({
                  query: 'query test{ testString }',
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.data).to.deep.equal(expected);
          });
      });

      it('can be called with an options function that returns a promise', () => {
          const app = express();
          app.use('/graphql', bodyParser.json());
          app.use('/graphql', graphqlHTTP( (req) => {
              return new Promise(resolve => {
                  resolve({schema: Schema});
              });
          }));
          const expected = {
              testString: 'it works',
          };
          const req = request(app)
              .post('/graphql')
              .send({
                  query: 'query test{ testString }',
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.data).to.deep.equal(expected);
          });
      });

      it('throws an error if POST body is missing', () => {
          const app = createApp({excludeParser: true});
          const req = request(app)
              .post('/graphql')
              .send({
                  query: 'query test{ testString }',
              });
          return req.then((res) => {
              expect(res.status).to.equal(500);
              return expect(res.error.text).to.contain('POST body missing.');
          });
      });


      it('can handle a basic request', () => {
          const app = createApp();
          const expected = {
              testString: 'it works',
          };
          const req = request(app)
              .post('/graphql')
              .send({
                  query: 'query test{ testString }',
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.data).to.deep.equal(expected);
          });
      });

      it('can handle a request with variables', () => {
          const app = createApp();
          const expected = {
              testArgument: 'hello world',
          };
          const req = request(app)
              .post('/graphql')
              .send({
                  query: 'query test($echo: String){ testArgument(echo: $echo) }',
                  variables: { echo: 'world' },
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.data).to.deep.equal(expected);
          });
      });

      it('can handle a request with variables as string', () => {
          const app = createApp();
          const expected = {
              testArgument: 'hello world',
          };
          const req = request(app)
              .post('/graphql')
              .send({
                  query: 'query test($echo: String!){ testArgument(echo: $echo) }',
                  variables: '{ "echo": "world" }',
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.data).to.deep.equal(expected);
          });
      });

      it('can handle a request with operationName', () => {
          const app = createApp();
          const expected = {
              testString: 'it works',
          };
          const req = request(app)
              .post('/graphql')
              .send({
                  query: `
                      query test($echo: String){ testArgument(echo: $echo) }
                      query test2{ testString }`,
                  variables: { echo: 'world' },
                  operationName: 'test2',
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.data).to.deep.equal(expected);
          });
      });

       it('can handle batch requests', () => {
          const app = createApp();
          const expected = [
              {
                  data: {
                      testString: 'it works',
                  },
              },
              {
                  data: {
                      testArgument: 'hello yellow',
                  },
              },
          ];
          const req = request(app)
              .post('/graphql')
              .send([{
                  query: `
                      query test($echo: String){ testArgument(echo: $echo) }
                      query test2{ testString }`,
                  variables: { echo: 'world' },
                  operationName: 'test2',
              },
              {
                  query: `
                      query testX($echo: String){ testArgument(echo: $echo) }`,
                  variables: { echo: 'yellow' },
                  operationName: 'testX',
              }]);
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body).to.deep.equal(expected);
          });
      });

      it('can handle a request with a mutation', () => {
          const app = createApp();
          const expected = {
              testMutation: 'not really a mutation, but who cares: world',
          };
          const req = request(app)
              .post('/graphql')
              .send({
                  query: 'mutation test($echo: String){ testMutation(echo: $echo) }',
                  variables: { echo: 'world' },
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.data).to.deep.equal(expected);
          });
      });

      it('applies the formatResponse function', () => {
          const app = createApp({apolloOptions: {
              schema: Schema,
              formatResponse(response) {
                  response['extensions'] = { it: 'works' }; return response;
              },
          }});
          const expected = { it: 'works' };
          const req = request(app)
              .post('/graphql')
              .send({
                  query: 'mutation test($echo: String){ testMutation(echo: $echo) }',
                  variables: { echo: 'world' },
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.extensions).to.deep.equal(expected);
          });
      });

    });


    describe('renderGraphiQL', () => {
      it('returns express middleware', () => {
          const query = `{ testString }`;
          const middleware = renderGraphiQL({
              endpointURL: '/graphql',
              query: query,
          });
          assert(typeof middleware === 'function');
      });

      it('presents GraphiQL when accepting HTML', () => {
          const app = createApp({graphiqlOptions: {
              endpointURL: '/graphql',
          }});

          const req = request(app)
              .get('/graphiql?query={test}')
              .set('Accept', 'text/html');
          return req.then((response) => {
              expect(response.status).to.equal(200);
              expect(response.type).to.equal('text/html');
              expect(response.text).to.include('{test}');
              expect(response.text).to.include('/graphql');
              expect(response.text).to.include('graphiql.min.js');
          });
      });
    });

    describe('stored queries', () => {
      it('works with formatParams', () => {
          const store = new OperationStore(Schema);
          store.put('query testquery{ testString }');
          const app = createApp({ apolloOptions: {
              schema: Schema,
              formatParams(params) {
                  params['query'] = store.get(params.operationName);
                  return params;
              },
          }});
          const expected = { testString: 'it works' };
          const req = request(app)
              .post('/graphql')
              .send({
                  operationName: 'testquery',
              });
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body.data).to.deep.equal(expected);
          });
      });

      it('can reject non-whitelisted queries', () => {
          const store = new OperationStore(Schema);
          store.put('query testquery{ testString }');
          const app = createApp({ apolloOptions: {
              schema: Schema,
              formatParams(params) {
                  if (params.query) {
                      throw new Error('Must not provide query, only operationName');
                  }
                  params['query'] = store.get(params.operationName);
                  return params;
              },
          }});
          const expected = [{
              data: {
                  testString: 'it works',
              },
          }, {
              errors: [{
                  message: 'Must not provide query, only operationName',
              }],
          }];

          const req = request(app)
              .post('/graphql')
              .send([{
                  operationName: 'testquery',
              }, {
                  query: '{ testString }',
              }]);
          return req.then((res) => {
              expect(res.status).to.equal(200);
              return expect(res.body).to.deep.equal(expected);
          });
      });
    });
  });
};