import React from 'react';
import ContractContext from './contract-context';
import PropTypes from 'prop-types';

class InstanceSelector extends React.Component {

  constructor(props) {
    super(props);
    this.state = {
      showInstances: false,
      showCustomAddressField: false,
      selectedInstance: props.selectedInstance,
      customInstance: "",
      error: false,
      errorMessage: ""
    };

    this.handleShowInstances = this.handleShowInstances.bind(this);
    this.handleChange = this.handleChange.bind(this);
    this.handleClick = this.handleClick.bind(this);
    this.handleTextChange = this.handleTextChange.bind(this);
  }

  handleTextChange(e) {
    this.setState({customInstance: e.target.value});
  }

  handleShowInstances(e) {
    e.preventDefault();
    this.setState({
      showInstances: !this.state.showInstances
    });
  }

  handleClick(e) {
    e.preventDefault();

    let instance;
    if (this.state.selectedInstance === "custom") {
      instance = this.state.customInstance;
    } else {
      instance = this.state.selectedInstance;
    }

    if (!(/^0x[0-9a-f]{40}$/i).test(instance)) {
      this.setState({error: true, errorMessage: 'Not a valid Ethereum address.'});
      console.log(this.state.errorMessage);
      return;
    } else {
      this.setState({error: false});
    }

    this.props.instanceUpdate(instance);

    this.setState({
      showInstances: false,
      showCustomAddressField: false,
      selectedInstance: instance,
      customInstance: this.state.selectedInstance === "custom" ? this.state.customInstance : ""
    });
  }

  handleChange(e) {
    this.setState({
      showCustomAddressField: e.target.value === "custom",
      selectedInstance: e.target.value
    });
  }

  render() {
    let showInstance;
    if (!this.state.showInstances) {
      showInstance = <a href="#" className="btn btn-primary btn-sm" onClick={this.handleShowInstances}>Change</a>;
    } else {
      showInstance = <a href="#" className="btn btn-secondary btn-sm" onClick={this.handleShowInstances}>Cancel</a>;
    }

    return <ContractContext.Consumer>
      {(context) => (<div className="contractSelection">
          <div className="card">
            <div className="card-header">
              <h3 className="card-title">
                Instance Selected: <b>{this.props.selectedInstance !== null ? this.props.selectedInstance : 'none'}</b>
              </h3>
              <div className="card-options">
                {showInstance}
              </div>
            </div>
            {
              this.state.showInstances && <React.Fragment>
                {
                  this.state.error && <div className="card-alert alert alert-danger mb-0">
                    {this.state.errorMessage}
                  </div>
                }
                <div className="card-body">
                  <div className="form-group control-group error">
                    <select className="form-control" id="contracts" value={this.state.selectedInstance}
                            onChange={this.handleChange}>
                      <option value="custom">Specific contract address</option>
                      {
                        context.instances.map(function(item, i) {
                          return <option key={i} value={item}>{item}</option>;
                        })
                      }
                    </select>
                    {
                      this.state.showCustomAddressField &&
                      <input type="text" className="form-control" id="specificAddress"
                             onChange={this.handleTextChange} placeholder="0x"/>
                    }
                  </div>
                </div>
                <div className="card-footer text-right">
                  <button className="btn btn-primary" onClick={this.handleClick}>Change</button>
                </div>
              </React.Fragment>
            }
          </div>
        </div>
      )}
    </ContractContext.Consumer>;
  }
}

InstanceSelector.propTypes = {
  instanceUpdate: PropTypes.func,
  selectedInstance: PropTypes.string
};

export default InstanceSelector;