import React from "react";
import PropTypes from "prop-types";
import Link from "component/link";

let scriptLoading = false;
let scriptLoaded = false;
let scriptDidError = false;

class CardVerify extends React.Component {
  static propTypes = {
    disabled: PropTypes.bool,

    label: PropTypes.string,

    // =====================================================
    // Required by stripe
    // see Stripe docs for more info:
    //   https://stripe.com/docs/checkout#integration-custom
    // =====================================================

    // Your publishable key (test or live).
    // can't use "key" as a prop in react, so have to change the keyname
    stripeKey: PropTypes.string.isRequired,

    // The callback to invoke when the Checkout process is complete.
    //   function(token)
    //     token is the token object created.
    //     token.id can be used to create a charge or customer.
    //     token.email contains the email address entered by the user.
    token: PropTypes.func.isRequired,
  };

  constructor(props) {
    super(props);
    this.state = {
      open: false,
    };
  }

  componentDidMount() {
    if (scriptLoaded) {
      return;
    }

    if (scriptLoading) {
      return;
    }

    scriptLoading = true;

    const script = document.createElement("script");
    script.src = "https://checkout.stripe.com/checkout.js";
    script.async = 1;

    this.loadPromise = (() => {
      let canceled = false;
      const promise = new Promise((resolve, reject) => {
        script.onload = () => {
          scriptLoaded = true;
          scriptLoading = false;
          resolve();
          this.onScriptLoaded();
        };
        script.onerror = event => {
          scriptDidError = true;
          scriptLoading = false;
          reject(event);
          this.onScriptError(event);
        };
      });
      const wrappedPromise = new Promise((accept, cancel) => {
        promise.then(
          () => (canceled ? cancel({ isCanceled: true }) : accept())
        );
        promise.catch(
          error => (canceled ? cancel({ isCanceled: true }) : cancel(error))
        );
      });

      return {
        promise: wrappedPromise,
        cancel() {
          canceled = true;
        },
      };
    })();

    this.loadPromise.promise
      .then(this.onScriptLoaded)
      .catch(this.onScriptError);

    document.body.appendChild(script);
  }

  componentDidUpdate() {
    if (!scriptLoading) {
      this.updateStripeHandler();
    }
  }

  componentWillUnmount() {
    if (this.loadPromise) {
      this.loadPromise.cancel();
    }
    if (CardVerify.stripeHandler && this.state.open) {
      CardVerify.stripeHandler.close();
    }
  }

  onScriptLoaded = () => {
    if (!CardVerify.stripeHandler) {
      CardVerify.stripeHandler = StripeCheckout.configure({
        key: this.props.stripeKey,
      });
      if (this.hasPendingClick) {
        this.showStripeDialog();
      }
    }
  };

  onScriptError = (...args) => {
    throw new Error("Unable to load credit validation script.");
  };

  onClosed = () => {
    this.setState({ open: false });
  };

  updateStripeHandler() {
    if (!CardVerify.stripeHandler) {
      CardVerify.stripeHandler = StripeCheckout.configure({
        key: this.props.stripeKey,
      });
    }
  }

  showStripeDialog() {
    this.setState({ open: true });
    CardVerify.stripeHandler.open({
      allowRememberMe: false,
      closed: this.onClosed,
      description: __("Confirm Identity"),
      email: this.props.email,
      locale: "auto",
      panelLabel: "Verify",
      token: this.props.token,
      zipCode: true,
    });
  }

  onClick = () => {
    if (scriptDidError) {
      try {
        throw new Error(
          "Tried to call onClick, but StripeCheckout failed to load"
        );
      } catch (x) {}
    } else if (CardVerify.stripeHandler) {
      this.showStripeDialog();
    } else {
      this.hasPendingClick = true;
    }
  };

  render() {
    return (
      <Link
        button="alt"
        label={this.props.label}
        icon="icon-lock"
        disabled={
          this.props.disabled || this.state.open || this.hasPendingClick
        }
        onClick={this.onClick.bind(this)}
      />
    );
  }
}

export default CardVerify;