import { CustomWrapper, Input, View } from '@tarojs/components'
import { memo, useEffect, useMemo, useRef, useState } from 'react'
import Big from 'big.js'
import styles from './index.module.scss'
type params = {
  minNum?: number //最小值
  maxNum?: number //最大值
  step?: number //步长
  defaultNum?: number //默认值
  digits?: number //多少位小数
  onChange?: (val: number) => void
  onBlue?: (val: number) => void //失去焦点触发
  onClickBtn?: (val: number) => void
  unit?: string
  disabled?: true | false //是否禁用
}
export default memo((props: params) => {
  return <Counter {...props}></Counter>
})

const Counter = memo((props: params) => {
  let { minNum = 0, maxNum = 10000, step = 1, digits = 0, defaultNum = 0, onChange, onBlue, onClickBtn, unit = '', disabled = false } = props
  const [value, setValue] = useState<any>({ count: defaultNum })
  useEffect(() => {
    setValue({ count: defaultNum })
  }, [defaultNum])
  const onPlus = () => {
    if (disabled) return false
    let count = value.count
    let num_res = Big(count).add(step).toNumber()
    num_res = num_res >= maxNum ? maxNum : num_res
    num_res = formatDigits(num_res)
    setValue({ ...value, count: num_res })
    onChange?.(parseFloat(num_res))
    onClickBtn?.(parseFloat(num_res))
  }
  const minus = () => {
    if (disabled) return false
    let count = value.count
    let num_res = Big(count).minus(step).toNumber()
    num_res = num_res < minNum ? minNum : num_res
    setValue({ ...value, count: num_res })
    onChange?.(parseFloat(num_res))
    onClickBtn?.(parseFloat(num_res))
  }

  //保留小数
  const formatDigits = (num) => {
    num = num + ''
    if (num.includes('.')) {
      let res = num.split('.')
      if (digits > 0) {
        let last_num = res[1].substr(0, digits)
        return res[0] + '.' + last_num
      } else {
        return res[0]
      }
    }

    return parseFloat(num)
  }

  //检查数据
  const checkData = (val) => {
    let num = parseFloat(val)
    if (num > maxNum) return maxNum
    if (num < minNum) return minNum
    return val
  }

  const onInputEven = (e) => {
    let res = e.detail.value
    if (res === '') {
      onChange?.(minNum)
    } else if (!isNaN(Number(res))) {
      let count = formatDigits(res)
      count = checkData(count)
      onChange?.(parseFloat(count as string))
    } else {
      let num = parseFloat(res)
      if (!isNaN(num)) {
        let count = formatDigits(num)
        count = checkData(count)
        onChange?.(count as number)
      } else {
        onChange?.(defaultNum)
      }
    }
  }

  const onBluerEven = (e) => {
    let num = parseFloat(e.detail.value)
    if (e.detail.value == '') {
      onBlue?.(minNum)
      setValue({ count: minNum })
    } else if (!isNaN(num)) {
      let count = formatDigits(num)
      count = checkData(count)
      setValue({ count })
      onBlue?.(count as number)
    } else {
      setValue({ count: minNum })
      onBlue?.(minNum)
    }
  }
  return (
    <View className={styles.main} onClick={(e) => e.stopPropagation()}>
      <View className={styles.reduce} onClick={() => minus()}>
        -
      </View>
      <View className={styles.input}>
        <Input type='digit' value={value.count} onInput={onInputEven} onBlur={onBluerEven} disabled={disabled} alwaysEmbed={true} cursorSpacing={150} />
        <View className={styles.unit}>{unit}</View>
      </View>
      <View className={styles.plus} onClick={() => onPlus()}>
        +
      </View>
    </View>
  )
})