import React, { useRef, useState, MouseEvent, useMemo, useImperativeHandle } from 'react'
import useScale, { withScale } from '../use-scale'
import useTheme from '../use-theme'
import ButtonDrip from './button.drip'
import ButtonLoading from './button-loading'
import { ButtonTypes } from '../utils/prop-types'
import { filterPropsWithGroup, getButtonChildrenWithIcon } from './utils'
import { useButtonGroupContext } from '../button-group/button-group-context'
import {
  getButtonColors,
  getButtonCursor,
  getButtonDripColor,
  getButtonHoverColors
} from './styles'
import useClasses from '../use-classes'

interface Props {
  href: React.AnchorHTMLAttributes<any>['href']
  type?: ButtonTypes
  ghost?: boolean
  loading?: boolean
  shadow?: boolean
  auto?: boolean
  effect?: boolean
  disabled?: boolean
  icon?: React.ReactNode
  iconRight?: React.ReactNode
  onClick?: React.MouseEventHandler<HTMLAnchorElement>
  className?: string
}

const defaultProps = {
  type: 'default' as ButtonTypes,
  ghost: false,
  loading: false,
  shadow: false,
  auto: false,
  effect: true,
  disabled: false,
  className: ''
}

type NativeAttrs = Omit<React.ButtonHTMLAttributes<any>, keyof Props>
export type ButtonProps = Props & NativeAttrs

const ButtonComponent = React.forwardRef<HTMLAnchorElement, React.PropsWithChildren<ButtonProps>>(
  (btnProps: ButtonProps, ref: React.Ref<HTMLAnchorElement | null>) => {
    const theme = useTheme()
    const { SCALES } = useScale()
    const buttonRef = useRef<HTMLAnchorElement>(null)
    useImperativeHandle(ref, () => buttonRef.current)

    const [dripShow, setDripShow] = useState<boolean>(false)
    const [dripX, setDripX] = useState<number>(0)
    const [dripY, setDripY] = useState<number>(0)
    const groupConfig = useButtonGroupContext()
    const filteredProps = filterPropsWithGroup(btnProps as any, groupConfig)
    const {
      children,
      disabled,
      type,
      loading,
      shadow,
      ghost,
      effect,
      onClick,
      auto,
      icon,
      iconRight,
      className,
      ...props
    } = filteredProps

    const { bg, border, color } = useMemo(
      () => getButtonColors(theme.palette, filteredProps),
      [theme.palette, filteredProps]
    )
    const hover = useMemo(
      () => getButtonHoverColors(theme.palette, filteredProps),
      [theme.palette, filteredProps]
    )
    const { cursor, events } = useMemo(
      () => getButtonCursor(!!disabled, loading),
      [disabled, loading]
    )
    const dripColor = useMemo(
      () => getButtonDripColor(theme.palette, filteredProps),
      [theme.palette, filteredProps]
    )

    /* istanbul ignore next */
    const dripCompletedHandle = () => {
      setDripShow(false)
      setDripX(0)
      setDripY(0)
    }

    const clickHandler = (event: MouseEvent<HTMLAnchorElement>) => {
      if (disabled || loading) {
        event.preventDefault()
        return
      }
      const showDrip = !shadow && !ghost && effect
      /* istanbul ignore next */
      if (showDrip && buttonRef.current) {
        const rect = buttonRef.current.getBoundingClientRect()
        setDripShow(true)
        setDripX(event.clientX - rect.left)
        setDripY(event.clientY - rect.top)
      }

      onClick && (onClick as React.MouseEventHandler<HTMLAnchorElement>)(event)
    }

    const childrenWithIcon = useMemo(
      () =>
        getButtonChildrenWithIcon(!!auto, children, {
          icon,
          iconRight
        }),
      [auto, children, icon, iconRight]
    )
    const [paddingLeft, paddingRight] = [
      auto ? SCALES.pl(1.15) : SCALES.pl(1.375),
      auto ? SCALES.pr(1.15) : SCALES.pr(1.375)
    ]

    return (
      <a
        ref={buttonRef}
        className={useClasses('btn', className)}
        onClick={clickHandler}
        href={!disabled ? btnProps.href : undefined}
        {...props}
      >
        {loading && <ButtonLoading color={color} />}
        {childrenWithIcon}
        {dripShow && (
          <ButtonDrip x={dripX} y={dripY} color={dripColor} onCompleted={dripCompletedHandle} />
        )}
        <style jsx>{`
          .btn {
            box-sizing: border-box;
            display: inline-block;
            line-height: ${SCALES.height(2.5)};
            border-radius: ${theme.layout.radius};
            font-weight: 400;
            font-size: ${SCALES.font(0.875)};
            user-select: none;
            outline: none;
            text-transform: capitalize;
            justify-content: center;
            text-align: center;
            white-space: nowrap;
            transition: background-color 200ms ease 0ms, box-shadow 200ms ease 0ms,
              border 200ms ease 0ms, color 200ms ease 0ms;
            position: relative;
            overflow: hidden;
            color: ${color};
            background-color: ${bg};
            border: 1px solid ${border};
            cursor: ${cursor};
            pointer-events: ${events};
            box-shadow: ${shadow ? theme.expressiveness.shadowSmall : 'none'};
            --hui-button-icon-padding: ${SCALES.pl(0.727)};
            --hui-button-height: ${SCALES.height(2.5)};
            --hui-button-color: ${color};
            --hui-button-bg: ${bg};
            min-width: ${auto ? 'min-content' : SCALES.width(10.5)};
            width: ${auto ? 'auto' : 'initial'};
            height: ${SCALES.height(2.5)};
            padding: ${SCALES.pt(0)} ${paddingRight} ${SCALES.pb(0)} ${paddingLeft};
            margin: ${SCALES.mt(0)} ${SCALES.mr(0)} ${SCALES.mb(0)} ${SCALES.ml(0)};
          }

          .btn:hover,
          .btn:focus {
            color: ${hover.color};
            --hui-button-color: ${hover.color};
            background-color: ${hover.bg};
            border-color: ${hover.border};
            cursor: ${cursor};
            pointer-events: ${events};
            box-shadow: ${shadow ? theme.expressiveness.shadowMedium : 'none'};
            transform: translate3d(0px, ${shadow ? '-1px' : '0px'}, 0px);
          }

          .btn :global(.text) {
            position: relative;
            z-index: 1;
            display: inline-flex;
            justify-content: center;
            align-items: center;
            text-align: center;
            line-height: inherit;
            top: -1px;
          }

          .btn :global(.text p),
          .btn :global(.text pre),
          .btn :global(.text div) {
            margin: 0;
          }
        `}</style>
      </a>
    )
  }
)

ButtonComponent.defaultProps = defaultProps
ButtonComponent.displayName = 'HuiButtonLink'
const Button = withScale(ButtonComponent)
export default Button