import React, { useEffect, useState } from "react";
import { motion } from "framer-motion";
import { Circle, FileText, Settings, ExternalLink, BarChart3, Network, Info, Bot } from "lucide-react";
import { Button } from "@/components/ui/button";
import { Popover } from "@/components/ui/popover";
import { LanguageSwitcher } from "@/components/LanguageSwitcher";
import { ThemeSwitcher } from "@/components/ThemeSwitcher";
import { useTranslation } from "@/hooks/useTranslation";
import { api, type ClaudeVersionStatus } from "@/lib/api";
import { cn } from "@/lib/utils";

interface TopbarProps {
  /**
   * Callback when CLAUDE.md is clicked
   */
  onClaudeClick: () => void;
  /**
   * Callback when Settings is clicked
   */
  onSettingsClick: () => void;
  /**
   * Callback when Usage Dashboard is clicked
   */
  onUsageClick: () => void;
  /**
   * Callback when MCP is clicked
   */
  onMCPClick: () => void;
  /**
   * Callback when Info is clicked
   */
  onInfoClick: () => void;
  /**
   * Callback when Agents is clicked
   */
  onAgentsClick?: () => void;
  /**
   * Optional className for styling
   */
  className?: string;
}

/**
 * Topbar component with status indicator and navigation buttons
 * 
 * @example
 * <Topbar
 *   onClaudeClick={() => setView('editor')}
 *   onSettingsClick={() => setView('settings')}
 *   onUsageClick={() => setView('usage-dashboard')}
 *   onMCPClick={() => setView('mcp')}
 * />
 */
export const Topbar: React.FC<TopbarProps> = ({
  onClaudeClick,
  onSettingsClick,
  onUsageClick,
  onMCPClick,
  onInfoClick,
  onAgentsClick,
  className,
}) => {
  const { t } = useTranslation();
  const [versionStatus, setVersionStatus] = useState<ClaudeVersionStatus | null>(null);
  const [checking, setChecking] = useState(true);
  
  // Check Claude version on mount
  useEffect(() => {
    checkVersion();
  }, []);
  
  const checkVersion = async () => {
    try {
      setChecking(true);
      const status = await api.checkClaudeVersion();
      setVersionStatus(status);
      
      // If Claude is not installed, prompt the selection/install dialog
      if (!status.is_installed) {
        // Emit an event that can be caught by the parent
        window.dispatchEvent(new CustomEvent('claude-not-found'));
      }
    } catch (err) {
      console.error("Failed to check Claude version:", err);
      setVersionStatus({
        is_installed: false,
        output: "Failed to check version",
      });
    } finally {
      setChecking(false);
    }
  };
  
  const StatusIndicator = () => {
    if (checking) {
      return (
        <div className="flex items-center space-x-2 text-xs">
          <Circle className="h-3 w-3 animate-pulse text-muted-foreground" />
          <span className="text-muted-foreground">Checking...</span>
        </div>
      );
    }
    
    if (!versionStatus) return null;
    
    const statusContent = (
      <Button
        variant="ghost"
        size="sm"
        className="h-auto py-1 px-2 hover:bg-accent"
        onClick={() => {
          // Emit event to return to home
          window.dispatchEvent(new CustomEvent('switch-to-welcome'));
        }}
        title={t('app.returnHome')}
      >
        <div className="flex items-center space-x-2 text-xs">
          <Circle
            className={cn(
              "h-3 w-3",
              versionStatus.is_installed 
                ? "fill-green-500 text-green-500" 
                : "fill-red-500 text-red-500"
            )}
          />
          <span>
            {versionStatus.is_installed && versionStatus.version
              ? `Claude Code v${versionStatus.version}`
              : "Claude Code"}
          </span>
        </div>
      </Button>
    );
    
    if (!versionStatus.is_installed) {
      return (
        <Popover
          trigger={statusContent}
          content={
            <div className="space-y-3 max-w-xs">
              <p className="text-sm font-medium">{t('messages.claudeCodeNotFound')}</p>
              <div className="rounded-md bg-muted p-3">
                <pre className="text-xs font-mono whitespace-pre-wrap">
                  {versionStatus.output}
                </pre>
              </div>
              <Button
                variant="outline"
                size="sm"
                className="w-full"
                onClick={onSettingsClick}
              >
                {t('messages.selectClaudeInstallation')}
              </Button>
              <a
                href="https://www.anthropic.com/claude-code"
                target="_blank"
                rel="noopener noreferrer"
                className="flex items-center space-x-1 text-xs text-primary hover:underline"
              >
                <span>{t('messages.installClaudeCode')}</span>
                <ExternalLink className="h-3 w-3" />
              </a>
            </div>
          }
          align="start"
        />
      );
    }
    
    return statusContent;
  };
  
  return (
    <motion.div
      initial={{ opacity: 0, y: -20 }}
      animate={{ opacity: 1, y: 0 }}
      transition={{ duration: 0.3 }}
      className={cn(
        "flex items-center justify-between px-4 py-3 border-b border-border bg-background/98 backdrop-blur-xl backdrop-saturate-[1.8] supports-[backdrop-filter]:bg-background/85 shadow-sm",
        className
      )}
    >
      {/* Status Indicator */}
      <StatusIndicator />
      
      {/* Action Buttons */}
      <div className="flex items-center space-x-2">
        {onAgentsClick && (
          <Button
            variant="ghost"
            size="sm"
            onClick={onAgentsClick}
            className="text-xs"
          >
            <Bot className="mr-2 h-3 w-3" />
            {t('navigation.agents')}
          </Button>
        )}
        
        <Button
          variant="ghost"
          size="sm"
          onClick={onUsageClick}
          className="text-xs"
        >
          <BarChart3 className="mr-2 h-3 w-3" />
          {t('navigation.usage')}
        </Button>
        
        <Button
          variant="ghost"
          size="sm"
          onClick={onClaudeClick}
          className="text-xs"
        >
          <FileText className="mr-2 h-3 w-3" />
          CLAUDE.md
        </Button>
        
        <Button
          variant="ghost"
          size="sm"
          onClick={onMCPClick}
          className="text-xs"
        >
          <Network className="mr-2 h-3 w-3" />
          {t('navigation.mcp')}
        </Button>
        
        <Button
          variant="ghost"
          size="sm"
          onClick={onSettingsClick}
          className="text-xs"
        >
          <Settings className="mr-2 h-3 w-3" />
          {t('navigation.settings')}
        </Button>
        
        {/* Language Switcher */}
        <LanguageSwitcher />
        
        {/* Theme Switcher */}
        <ThemeSwitcher />
        
        <Button
          variant="ghost"
          size="icon"
          onClick={onInfoClick}
          className="h-8 w-8"
          title={t('navigation.about')}
        >
          <Info className="h-4 w-4" />
        </Button>
      </div>
    </motion.div>
  );
};