import React, { Component } from 'react'
import cm from 'codemirror'
import { getKey, isCtrlKey } from '../util/keys'

if (typeof window !== 'undefined') {
  require('codemirror/mode/markdown/markdown')
}
export default class CodeMirror extends Component {
  handleChange = () => {
    if (!this.editor) return
    const value = this.editor.getValue()
    if (value !== this.props.value) {
      this.props.onChange && this.props.onChange(value)
      if (this.editor.getValue() !== this.props.value) {
        if (this.state.isControlled) {
          this.editor.setValue(this.props.value)
        } else {
          this.props.value = value
        }
      }
    }
  }
  checkSubmit = (cm, e) => {
    const key = getKey(e)
    if (isCtrlKey(key)) {
      this.ctrlKey = true
    } else if (key === 13 && this.ctrlKey) {
      this.props.onSubmit()
    }
  }
  handleKeyUp = (cm, e) => {
    if (isCtrlKey(getKey(e))) this.ctrlKey = false
  }
  componentDidMount() {
    if (typeof window === 'undefined') return
    this.editor = cm.fromTextArea(this.textarea, this.props.options)
    this.editor.on('change', this.handleChange)
    if (typeof this.props.onSubmit === 'function') {
      this.editor.on('keydown', this.checkSubmit)
      this.editor.on('keyup', this.handleKeyUp)
      this.setupSubmitKey = true
    }
  }
  componentWillUnmount() {
    if (this.setupSubmitKey) {
      this.editor.off('keydown', this.checkSubmit)
      this.editor.off('keyup', this.handleKeyUp)
      this.setupSubmitKey = false
    }
  }
  componentDidUpdate() {
    if (!this.editor || !this.props.value) return
    if (this.editor.getValue() !== this.props.value) {
      this.editor.setValue(this.props.value)
    }
  }
  render() {
    const { value, className, onChange } = this.props
    return (
      <div {...{ className }}>
        <textarea {...{ value, onChange }} ref={el => (this.textarea = el)} />
      </div>
    )
  }
}