import React from 'react'
import { View, Text } from '@tarojs/components'
import { cn } from '@/utils/cn'
import Taro from '@tarojs/taro'
import { isWeapp } from '@/utils/platform'

export interface NavbarProps {
  title?: string
  leftText?: string
  leftIcon?: string
  rightText?: string
  rightIcon?: string
  backgroundColor?: string
  textColor?: string
  border?: boolean
  fixed?: boolean
  placeholder?: boolean
  onClickLeft?: () => void
  onClickRight?: () => void
  children?: React.ReactNode
  className?: string
  /** 是否在小程序环境下隐藏右侧按钮（默认false，会自动避让） */
  hideRightInWeapp?: boolean
}

const systemInfo = Taro.getSystemInfoSync()
const menuButtonInfo = Taro.getMenuButtonBoundingClientRect()

// 计算导航栏高度
const NAVBAR_HEIGHT = 44
const STATUS_BAR_HEIGHT = systemInfo.statusBarHeight || 0
const TOTAL_HEIGHT = STATUS_BAR_HEIGHT + NAVBAR_HEIGHT

export const Navbar: React.FC<NavbarProps> = ({
  title,
  leftText,
  leftIcon = 'i-heroicons-chevron-left-20-solid',
  rightText,
  rightIcon,
  backgroundColor = 'bg-white',
  textColor = 'text-gray-900',
  border = true,
  fixed = true,
  placeholder = true,
  onClickLeft,
  onClickRight,
  children,
  className,
  hideRightInWeapp,
}) => {
  // 处理左侧点击
  const handleLeftClick = () => {
    if (onClickLeft) {
      onClickLeft()
    } else {
      // 默认返回上一页
      Taro.navigateBack()
    }
  }

  // 渲染左侧内容
  const renderLeft = () => {
    if (children) return null
    
    return (
      <View 
        className="absolute left-3 top-0 bottom-0 flex items-center z-10"
        style={{ height: NAVBAR_HEIGHT }}
        onClick={handleLeftClick}
      >
        <View className="flex items-center">
          {leftIcon && (
            <View className={cn(leftIcon, 'w-5 h-5', textColor)} />
          )}
          {leftText && (
            <Text className={cn('ml-1 text-sm', textColor)}>{leftText}</Text>
          )}
        </View>
      </View>
    )
  }

  // 渲染右侧内容
  const renderRight = () => {
    if (!rightText && !rightIcon || (hideRightInWeapp && isWeapp())) return null
        
    if (isWeapp() && menuButtonInfo) {
      // 小程序环境下，调整右侧按钮位置
      return (
        <View
          className="absolute top-0 bottom-0 flex items-center z-10"
          style={{
            height: NAVBAR_HEIGHT,
            right: `${menuButtonInfo.right + 10}px`,
          }}
          onClick={onClickRight}
        >
          <View className="flex items-center">
            {rightText && (
              <Text className={cn('mr-1 text-sm', textColor)}>{rightText}</Text>
            )}
            {rightIcon && (
              <View className={cn(rightIcon, 'w-5 h-5', textColor)} />
            )}
          </View>
        </View>
      )
    }
    
    // H5或其他平台，保持原有样式
    return (
      <View
        className="absolute right-3 top-0 bottom-0 flex items-center z-10"
        style={{ height: NAVBAR_HEIGHT }}
        onClick={onClickRight}
      >
        <View className="flex items-center">
          {rightText && (
            <Text className={cn('mr-1 text-sm', textColor)}>{rightText}</Text>
          )}
          {rightIcon && (
            <View className={cn(rightIcon, 'w-5 h-5', textColor)} />
          )}
        </View>
      </View>
    )
  }

  // 渲染标题
  const renderTitle = () => {
    if (children) return children
    
    if (isWeapp() && menuButtonInfo) {
      // 小程序环境下，调整标题位置
      return (
        <View className="flex-1 flex items-center justify-center">
          <Text
            className={cn('text-base font-semibold truncate', textColor)}
            style={{
              maxWidth: `calc(100% - ${menuButtonInfo.right + 10}px - 60px - 60px)`
            }}
          >
            {title}
          </Text>
        </View>
      )
    }
    
    // H5或其他平台，保持原有样式
    return (
      <Text className={cn('text-base font-semibold', textColor)}>
        {title}
      </Text>
    )
  }

  // 导航栏样式
  const navbarStyle = {
    height: TOTAL_HEIGHT,
    paddingTop: STATUS_BAR_HEIGHT,
  }

  return (
    <>
      <View
        className={cn(
          'relative w-full',
          backgroundColor,
          border && 'border-b border-gray-200',
          fixed && 'fixed top-0 left-0 right-0 z-50',
          className
        )}
        style={navbarStyle}
      >
        {/* 导航栏内容 */}
        <View
          className="relative flex items-center justify-center"
          style={{ height: NAVBAR_HEIGHT }}
        >
          {renderLeft()}
          {renderTitle()}
          {renderRight()}
        </View>
      </View>
      
      {/* 占位元素 */}
      {fixed && placeholder && (
        <View style={{ height: TOTAL_HEIGHT }} />
      )}
    </>
  )
}

// 预设样式
export const NavbarPresets = {
  // 默认白色导航栏
  default: {
    backgroundColor: 'bg-white',
    textColor: 'text-gray-900',
    border: true,
  },
  
  // 深色导航栏
  dark: {
    backgroundColor: 'bg-gray-900',
    textColor: 'text-white',
    border: true,
  },
  
  // 透明导航栏
  transparent: {
    backgroundColor: 'bg-transparent',
    textColor: 'text-white',
    border: false,
  },
  
  // 主色调导航栏
  primary: {
    backgroundColor: 'bg-blue-500',
    textColor: 'text-white',
    border: false,
  },
}

// 快捷创建函数
export const createNavbar = (preset: keyof typeof NavbarPresets) => {
  return NavbarPresets[preset]
}

export default Navbar