web2.0-frontend/src/pages/SignUpPage/SignUpPage.tsx

import * as React from "react";
import Helmet from "react-helmet";
import "./SignUpPage.scss";
import { getForm, SignupForm } from "../../models/SignupForm";
import PageSection from "../../components/PageSection";
import { ColorEnum } from "../../index";
import { Question, optionTypes } from "../../components/SignupQuestionsWidget";

export interface SignUpPageProps {
  match: {
    params: {
      id: number;
    },
  };
}

export interface SignUpPageState {
  signUpForm: SignupForm | null;
}

class SignUpPage extends React.Component<SignUpPageProps, SignUpPageState> {
  constructor(props) {
    super(props);
    const { staticContext } = props;

    if (staticContext) {
      /* The static context is an object that manages promises when
         rendering on the server. If staticContext exists, that means
         we have to store all promises in it. Otherwise, operate
         normally. See server/index.ts. */
      if (staticContext.resolutions.getSignUpForm) {
        const signUpForm = staticContext.resolutions.getSignUpForm as SignupForm;
        this.state = {
          signUpForm,
        };
      } else {
        this.state = {
          signUpForm: null,
        };
        const promiseSignUpForm = this.fetchSignUp();
        staticContext.promises.getSignUpForm = promiseSignUpForm;
      }
    } else {
      this.state = {
        signUpForm: null,
      };
      this.fetchSignUp();
    }
  }

  fetchSignUp = (): Promise<SignupForm> => {
    const { match } = this.props;
    const { id } = match.params;
    const formPromise = getForm(id);
    formPromise.then(signUpForm => {
      this.setState({
        signUpForm,
      });
    });
    return formPromise;
  }

  renderAnswerInput = (question: Question) => {
    if (!optionTypes.includes(question.type)) {
      throw new Error("Unknown question type");
    }

    if (question.type === "text") {
      return <input type="text" name={question.id} />;
    }
    if (question.type === "radiobutton") {
      const options = question.options;
      return options.map((opt) => (
        <span>
          <input type="radio" name={`${question.id}`} />
          {opt}
        </span>
      ));
    }
  }

  renderQuestion = (question: Question) => {
    return (
      <div className="question">
        {question.name}
        {this.renderAnswerInput(question)}
      </div>
    );
  }

  renderForm() {
    const { signUpForm } = this.state;
    const questions: Question[] = JSON.parse(signUpForm.questions);
    const content = questions.map(this.renderQuestion);

    return (
      <div>
        <h1>Title: {signUpForm.title}</h1>
        <div>
          {content}
        </div>
      </div>
    );
  }

  render() {
    const { match } = this.props;
    const { id } = match.params;
    const { signUpForm } = this.state;

    const content = signUpForm !== null
      ? this.renderForm()
      : <div>Loading...</div>;

    return (
      <div className="sign-up-page">
        <Helmet>
          <link rel="canonical" href={`https://sik.ayy.fi/signup/${id}`} />
        </Helmet>
        <PageSection backgroundColor={ColorEnum.DarkBlue}>
          {content}
        </PageSection>
      </div>
    );
  }
}

export default SignUpPage;