import type { CSSInterpolation, CSSObject } from '@antd-tiny-vue/cssinjs'
import type { FullToken, GenerateStyle } from '../../theme/internal'
import { genComponentStyleHook, mergeToken } from '../../theme/internal'
import { genFocusStyle } from '../../style'
import { genCompactItemStyle } from '../../style/compact-item'
import { genCompactItemVerticalStyle } from '../../style/compact-item-vertical'
import genGroupStyle from './group'

/** Component only token. Which will handle additional calculation of alias token */
export interface ComponentToken {}

export interface ButtonToken extends FullToken<'Button'> {
  // FIXME: should be removed
  colorOutlineDefault: string
  buttonPaddingHorizontal: number
}

// ============================== Shared ==============================
const genSharedButtonStyle: GenerateStyle<ButtonToken, CSSObject> = (token): CSSObject => {
  const { componentCls, iconCls } = token

  return {
    [componentCls]: {
      outline: 'none',
      position: 'relative',
      display: 'inline-block',
      fontWeight: 400,
      whiteSpace: 'nowrap',
      textAlign: 'center',
      backgroundImage: 'none',
      backgroundColor: 'transparent',
      border: `${token.lineWidth}px ${token.lineType} transparent`,
      cursor: 'pointer',
      transition: `all ${token.motionDurationMid} ${token.motionEaseInOut}`,
      userSelect: 'none',
      touchAction: 'manipulation',
      lineHeight: token.lineHeight,
      color: token.colorText,

      '> span': {
        display: 'inline-block'
      },

      // Leave a space between icon and text.
      [`> ${iconCls} + span, > span + ${iconCls}`]: {
        marginInlineStart: token.marginXS
      },

      '> a': {
        color: 'currentColor'
      },

      '&:not(:disabled)': {
        ...genFocusStyle(token)
      },

      // make `btn-icon-only` not too narrow
      [`&-icon-only${componentCls}-compact-item`]: {
        flex: 'none'
      },
      // Special styles for Primary Button
      [`&-compact-item${componentCls}-primary`]: {
        [`&:not([disabled]) + ${componentCls}-compact-item${componentCls}-primary:not([disabled])`]: {
          position: 'relative',

          '&:before': {
            position: 'absolute',
            top: -token.lineWidth,
            insetInlineStart: -token.lineWidth,
            display: 'inline-block',
            width: token.lineWidth,
            height: `calc(100% + ${token.lineWidth * 2}px)`,
            backgroundColor: token.colorPrimaryHover,
            content: '""'
          }
        }
      },
      // Special styles for Primary Button
      '&-compact-vertical-item': {
        [`&${componentCls}-primary`]: {
          [`&:not([disabled]) + ${componentCls}-compact-vertical-item${componentCls}-primary:not([disabled])`]: {
            position: 'relative',

            '&:before': {
              position: 'absolute',
              top: -token.lineWidth,
              insetInlineStart: -token.lineWidth,
              display: 'inline-block',
              width: `calc(100% + ${token.lineWidth * 2}px)`,
              height: token.lineWidth,
              backgroundColor: token.colorPrimaryHover,
              content: '""'
            }
          }
        }
      }
    }
  }
}

const genHoverActiveButtonStyle = (hoverStyle: CSSObject, activeStyle: CSSObject): CSSObject => ({
  '&:not(:disabled)': {
    '&:hover': hoverStyle,
    '&:active': activeStyle
  }
})

// ============================== Shape ===============================
const genCircleButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  minWidth: token.controlHeight,
  paddingInlineStart: 0,
  paddingInlineEnd: 0,
  borderRadius: '50%'
})

const genRoundButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  borderRadius: token.controlHeight,
  paddingInlineStart: token.controlHeight / 2,
  paddingInlineEnd: token.controlHeight / 2
})

// =============================== Type ===============================
const genDisabledStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  cursor: 'not-allowed',
  borderColor: token.colorBorder,
  color: token.colorTextDisabled,
  backgroundColor: token.colorBgContainerDisabled,
  boxShadow: 'none'
})

const genGhostButtonStyle = (
  btnCls: string,
  textColor: string | false,
  borderColor: string | false,
  textColorDisabled: string | false,
  borderColorDisabled: string | false,
  hoverStyle?: CSSObject,
  activeStyle?: CSSObject
): CSSObject => ({
  [`&${btnCls}-background-ghost`]: {
    color: textColor || undefined,
    backgroundColor: 'transparent',
    borderColor: borderColor || undefined,
    boxShadow: 'none',

    ...genHoverActiveButtonStyle(
      {
        backgroundColor: 'transparent',
        ...hoverStyle
      },
      {
        backgroundColor: 'transparent',
        ...activeStyle
      }
    ),

    '&:disabled': {
      cursor: 'not-allowed',
      color: textColorDisabled || undefined,
      borderColor: borderColorDisabled || undefined
    }
  }
})

const genSolidDisabledButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  '&:disabled': {
    ...genDisabledStyle(token)
  }
})

const genSolidButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  ...genSolidDisabledButtonStyle(token)
})

const genPureDisabledButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  '&:disabled': {
    cursor: 'not-allowed',
    color: token.colorTextDisabled
  }
})

// Type: Default
const genDefaultButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  ...genSolidButtonStyle(token),

  backgroundColor: token.colorBgContainer,
  borderColor: token.colorBorder,

  boxShadow: `0 ${token.controlOutlineWidth}px 0 ${token.controlTmpOutline}`,

  ...genHoverActiveButtonStyle(
    {
      color: token.colorPrimaryHover,
      borderColor: token.colorPrimaryHover
    },
    {
      color: token.colorPrimaryActive,
      borderColor: token.colorPrimaryActive
    }
  ),

  ...genGhostButtonStyle(token.componentCls, token.colorBgContainer, token.colorBgContainer, token.colorTextDisabled, token.colorBorder),

  [`&${token.componentCls}-dangerous`]: {
    color: token.colorError,
    borderColor: token.colorError,

    ...genHoverActiveButtonStyle(
      {
        color: token.colorErrorHover,
        borderColor: token.colorErrorBorderHover
      },
      {
        color: token.colorErrorActive,
        borderColor: token.colorErrorActive
      }
    ),

    ...genGhostButtonStyle(token.componentCls, token.colorError, token.colorError, token.colorTextDisabled, token.colorBorder),
    ...genSolidDisabledButtonStyle(token)
  }
})

// Type: Primary
const genPrimaryButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  ...genSolidButtonStyle(token),

  color: token.colorTextLightSolid,
  backgroundColor: token.colorPrimary,

  boxShadow: `0 ${token.controlOutlineWidth}px 0 ${token.controlOutline}`,

  ...genHoverActiveButtonStyle(
    {
      color: token.colorTextLightSolid,
      backgroundColor: token.colorPrimaryHover
    },
    {
      color: token.colorTextLightSolid,
      backgroundColor: token.colorPrimaryActive
    }
  ),

  ...genGhostButtonStyle(
    token.componentCls,
    token.colorPrimary,
    token.colorPrimary,
    token.colorTextDisabled,
    token.colorBorder,
    {
      color: token.colorPrimaryHover,
      borderColor: token.colorPrimaryHover
    },
    {
      color: token.colorPrimaryActive,
      borderColor: token.colorPrimaryActive
    }
  ),

  [`&${token.componentCls}-dangerous`]: {
    backgroundColor: token.colorError,
    boxShadow: `0 ${token.controlOutlineWidth}px 0 ${token.colorErrorOutline}`,

    ...genHoverActiveButtonStyle(
      {
        backgroundColor: token.colorErrorHover
      },
      {
        backgroundColor: token.colorErrorActive
      }
    ),

    ...genGhostButtonStyle(
      token.componentCls,
      token.colorError,
      token.colorError,
      token.colorTextDisabled,
      token.colorBorder,
      {
        color: token.colorErrorHover,
        borderColor: token.colorErrorHover
      },
      {
        color: token.colorErrorActive,
        borderColor: token.colorErrorActive
      }
    ),
    ...genSolidDisabledButtonStyle(token)
  }
})

// Type: Dashed
const genDashedButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  ...genDefaultButtonStyle(token),
  borderStyle: 'dashed'
})

// Type: Link
const genLinkButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  color: token.colorLink,

  ...genHoverActiveButtonStyle(
    {
      color: token.colorLinkHover
    },
    {
      color: token.colorLinkActive
    }
  ),

  ...genPureDisabledButtonStyle(token),

  [`&${token.componentCls}-dangerous`]: {
    color: token.colorError,

    ...genHoverActiveButtonStyle(
      {
        color: token.colorErrorHover
      },
      {
        color: token.colorErrorActive
      }
    ),

    ...genPureDisabledButtonStyle(token)
  }
})

// Type: Text
const genTextButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  ...genHoverActiveButtonStyle(
    {
      color: token.colorText,
      backgroundColor: token.colorBgTextHover
    },
    {
      color: token.colorText,
      backgroundColor: token.colorBgTextActive
    }
  ),

  ...genPureDisabledButtonStyle(token),

  [`&${token.componentCls}-dangerous`]: {
    color: token.colorError,

    ...genPureDisabledButtonStyle(token),
    ...genHoverActiveButtonStyle(
      {
        color: token.colorErrorHover,
        backgroundColor: token.colorErrorBg
      },
      {
        color: token.colorErrorHover,
        backgroundColor: token.colorErrorBg
      }
    )
  }
})

// Href and Disabled
const genDisabledButtonStyle: GenerateStyle<ButtonToken, CSSObject> = token => ({
  ...genDisabledStyle(token),
  [`&${token.componentCls}:hover`]: {
    ...genDisabledStyle(token)
  }
})

const genTypeButtonStyle: GenerateStyle<ButtonToken> = token => {
  const { componentCls } = token

  return {
    [`${componentCls}-default`]: genDefaultButtonStyle(token),
    [`${componentCls}-primary`]: genPrimaryButtonStyle(token),
    [`${componentCls}-dashed`]: genDashedButtonStyle(token),
    [`${componentCls}-link`]: genLinkButtonStyle(token),
    [`${componentCls}-text`]: genTextButtonStyle(token),
    [`${componentCls}-disabled`]: genDisabledButtonStyle(token)
  }
}

// =============================== Size ===============================
const genSizeButtonStyle = (token: ButtonToken, sizePrefixCls = ''): CSSInterpolation => {
  const { componentCls, iconCls, controlHeight, fontSize, lineHeight, lineWidth, borderRadius, buttonPaddingHorizontal } = token

  const paddingVertical = Math.max(0, (controlHeight - fontSize * lineHeight) / 2 - lineWidth)
  const paddingHorizontal = buttonPaddingHorizontal - lineWidth

  const iconOnlyCls = `${componentCls}-icon-only`

  return [
    // Size
    {
      [`${componentCls}${sizePrefixCls}`]: {
        fontSize,
        height: controlHeight,
        padding: `${paddingVertical}px ${paddingHorizontal}px`,
        borderRadius,

        [`&${iconOnlyCls}`]: {
          width: controlHeight,
          paddingInlineStart: 0,
          paddingInlineEnd: 0,
          [`&${componentCls}-round`]: {
            width: 'auto'
          },
          '> span': {
            transform: 'scale(1.143)' // 14px -> 16px
          }
        },

        // Loading
        [`&${componentCls}-loading`]: {
          opacity: token.opacityLoading,
          cursor: 'default'
        },

        [`${componentCls}-loading-icon`]: {
          transition: `width ${token.motionDurationSlow} ${token.motionEaseInOut}, opacity ${token.motionDurationSlow} ${token.motionEaseInOut}`
        },

        [`&:not(${iconOnlyCls}) ${componentCls}-loading-icon > ${iconCls}`]: {
          marginInlineEnd: token.marginXS
        }
      }
    },

    // Shape - patch prefixCls again to override solid border radius style
    {
      [`${componentCls}${componentCls}-circle${sizePrefixCls}`]: genCircleButtonStyle(token)
    },
    {
      [`${componentCls}${componentCls}-round${sizePrefixCls}`]: genRoundButtonStyle(token)
    }
  ]
}

const genSizeBaseButtonStyle: GenerateStyle<ButtonToken> = token => genSizeButtonStyle(token)

const genSizeSmallButtonStyle: GenerateStyle<ButtonToken> = token => {
  const smallToken = mergeToken<ButtonToken>(token, {
    controlHeight: token.controlHeightSM,
    padding: token.paddingXS,
    buttonPaddingHorizontal: 8, // Fixed padding
    borderRadius: token.borderRadiusSM
  })

  return genSizeButtonStyle(smallToken, `${token.componentCls}-sm`)
}

const genSizeLargeButtonStyle: GenerateStyle<ButtonToken> = token => {
  const largeToken = mergeToken<ButtonToken>(token, {
    controlHeight: token.controlHeightLG,
    fontSize: token.fontSizeLG,
    borderRadius: token.borderRadiusLG
  })

  return genSizeButtonStyle(largeToken, `${token.componentCls}-lg`)
}

const genBlockButtonStyle: GenerateStyle<ButtonToken> = token => {
  const { componentCls } = token
  return {
    [componentCls]: {
      [`&${componentCls}-block`]: {
        width: '100%'
      }
    }
  }
}

// ============================== Export ==============================
export default genComponentStyleHook('Button', token => {
  const { controlTmpOutline, paddingContentHorizontal } = token

  const buttonToken = mergeToken<ButtonToken>(token, {
    colorOutlineDefault: controlTmpOutline,
    buttonPaddingHorizontal: paddingContentHorizontal
  })

  return [
    // Shared
    genSharedButtonStyle(buttonToken),

    // Size
    genSizeSmallButtonStyle(buttonToken),
    genSizeBaseButtonStyle(buttonToken),
    genSizeLargeButtonStyle(buttonToken),

    // Block
    genBlockButtonStyle(buttonToken),

    // Group (type, ghost, danger, disabled, loading)
    genTypeButtonStyle(buttonToken),

    // Button Group
    genGroupStyle(buttonToken),

    // Space Compact
    genCompactItemStyle(token, { focus: false }),
    genCompactItemVerticalStyle(token)
  ]
})