import { useState, useCallback, useEffect } from 'react';
import { invoke } from '@tauri-apps/api/core';
import { Button } from '@/components/ui/button';
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from '@/components/ui/card';
import { Badge } from '@/components/ui/badge';
import { CodeHighlighter } from '@/components/ui/code-highlighter';
import { Copy, Check, FileCode, Sparkles, Minimize2, CheckCircle2, XCircle, Upload, ChevronLeft, ChevronRight } from 'lucide-react';
import type { XmlFormatConfig, XmlFormatResult, XmlValidateResult } from '@/types/xml';

export function XmlFormatterPage() {
  const [input, setInput] = useState('');
  const [output, setOutput] = useState('');
  const [validation, setValidation] = useState<XmlValidateResult | null>(null);
  const [config, setConfig] = useState<XmlFormatConfig>({
    indent: 2,
    mode: 'pretty',
  });
  const [copied, setCopied] = useState(false);
  const [isProcessing, setIsProcessing] = useState(false);
  const [isInputCollapsed, setIsInputCollapsed] = useState(false);

  useEffect(() => {
    if (input.trim()) {
      validateXml();
    } else {
      setValidation(null);
    }
  }, [input]);

  const validateXml = useCallback(async () => {
    if (!input.trim()) {
      setValidation(null);
      return;
    }

    try {
      const result = await invoke<XmlValidateResult>('validate_xml', { input });
      setValidation(result);
    } catch (error) {
      console.error('验证失败:', error);
    }
  }, [input]);

  const formatXml = useCallback(async () => {
    if (!input.trim()) return;

    setIsProcessing(true);
    try {
      const result = await invoke<XmlFormatResult>('format_xml', { input, config });
      if (result.success) {
        setOutput(result.result);
        // 格式化成功后自动收起输入区域
        setIsInputCollapsed(true);
      } else {
        setOutput(result.error || '格式化失败');
      }
    } catch (error) {
      console.error('格式化失败:', error);
      setOutput('错误: ' + String(error));
    } finally {
      setIsProcessing(false);
    }
  }, [input, config]);

  const compactXml = useCallback(async () => {
    if (!input.trim()) return;

    setIsProcessing(true);
    try {
      const result = await invoke<XmlFormatResult>('compact_xml', { input });
      if (result.success) {
        setOutput(result.result);
      } else {
        setOutput(result.error || '压缩失败');
      }
    } catch (error) {
      console.error('压缩失败:', error);
      setOutput('错误: ' + String(error));
    } finally {
      setIsProcessing(false);
    }
  }, [input]);

  const copyToClipboard = useCallback(async () => {
    if (!output) return;
    try {
      await navigator.clipboard.writeText(output);
      setCopied(true);
      setTimeout(() => setCopied(false), 2000);
    } catch (error) {
      console.error('复制失败:', error);
    }
  }, [output]);

  const clearInput = useCallback(() => {
    setInput('');
    setOutput('');
    setValidation(null);
  }, []);

  const loadExample = useCallback(() => {
    const example = '<?xml version="1.0" encoding="UTF-8"?><root><item id="1"><name>示例</name><value>测试</value></item></root>';
    setInput(example);
  }, []);

  return (
    <div className="flex flex-col h-screen bg-background">
      <header className="border-b bg-background/95 backdrop-blur flex-shrink-0">
        <div className="container mx-auto px-4 py-4">
          <div className="flex items-center gap-3">
            <Button variant="ghost" size="sm" onClick={() => window.history.back()}>
              ← 返回
            </Button>
            <div className="flex items-center gap-2">
              <FileCode className="w-6 h-6 text-primary" />
              <h1 className="text-xl font-bold">XML 格式化工具</h1>
            </div>
          </div>
        </div>
      </header>

      <main className="flex-1 container mx-auto px-4 py-6 overflow-y-auto">
        <div className="max-w-6xl mx-auto space-y-6">
          <Card>
            <CardHeader>
              <CardTitle className="text-lg">配置选项</CardTitle>
              <CardDescription>自定义 XML 格式化行为</CardDescription>
            </CardHeader>
            <CardContent>
              <div className="flex flex-wrap items-center gap-6">
                <div className="flex items-center gap-3">
                  <label className="text-sm font-medium">缩进:</label>
                  <div className="flex gap-1">
                    {[2, 4].map((spaces) => (
                      <Button
                        key={spaces}
                        size="sm"
                        variant={config.indent === spaces ? 'default' : 'outline'}
                        onClick={() => setConfig({ ...config, indent: spaces })}
                      >
                        {spaces} 空格
                      </Button>
                    ))}
                  </div>
                </div>
                <div className="flex items-center gap-3">
                  <label className="text-sm font-medium">模式:</label>
                  <div className="flex gap-1">
                    {(['pretty', 'compact'] as const).map((mode) => (
                      <Button
                        key={mode}
                        size="sm"
                        variant={config.mode === mode ? 'default' : 'outline'}
                        onClick={() => setConfig({ ...config, mode })}
                      >
                        {mode === 'pretty' ? '美化' : '压缩'}
                      </Button>
                    ))}
                  </div>
                </div>
              </div>
            </CardContent>
          </Card>

          <div className="grid grid-cols-1 lg:grid-cols-2 gap-6 relative">
            {/* 收起/展开切换按钮 */}
            <Button
              variant="outline"
              size="sm"
              onClick={() => setIsInputCollapsed(!isInputCollapsed)}
              className="absolute left-1/2 -translate-x-1/2 -top-3 z-10 gap-1 shadow-md"
            >
              {isInputCollapsed ? (
                <>
                  <ChevronRight className="w-4 h-4" />
                  显示输入
                </>
              ) : (
                <>
                  <ChevronLeft className="w-4 h-4" />
                  隐藏输入
                </>
              )}
            </Button>

            {!isInputCollapsed && (
            <Card>
              <CardHeader>
                <div className="flex items-center justify-between">
                  <div>
                    <CardTitle className="text-lg">输入 XML</CardTitle>
                    <CardDescription>粘贴或输入 XML 数据</CardDescription>
                  </div>
                  <div className="flex gap-2">
                    <Button size="sm" variant="outline" onClick={loadExample}>
                      <Upload className="w-4 h-4 mr-1" />
                      示例
                    </Button>
                    {input && (
                      <Button size="sm" variant="ghost" onClick={clearInput}>
                        清空
                      </Button>
                    )}
                  </div>
                </div>
              </CardHeader>
              <CardContent>
                <div className="relative">
                  <textarea
                    value={input}
                    onChange={(e) => setInput(e.target.value)}
                    className="w-full h-96 p-4 font-mono text-sm bg-muted rounded-lg resize-none focus:outline-none focus:ring-2 focus:ring-primary"
                    placeholder="在此输入 XML..."
                    spellCheck={false}
                  />
                  {validation && (
                    <div className="absolute top-2 right-2">
                      {validation.isValid ? (
                        <Badge variant="default" className="gap-1 bg-green-500 hover:bg-green-600">
                          <CheckCircle2 className="w-3 h-3" />
                          有效
                        </Badge>
                      ) : (
                        <Badge variant="destructive" className="gap-1">
                          <XCircle className="w-3 h-3" />
                          无效
                        </Badge>
                      )}
                    </div>
                  )}
                </div>
                {validation && !validation.isValid && validation.errorMessage && (
                  <div className="mt-3 p-3 bg-destructive/10 border border-destructive/20 rounded-lg">
                    <p className="text-sm text-destructive font-medium">{validation.errorMessage}</p>
                  </div>
                )}
                <div className="flex gap-2 mt-4">
                  <Button onClick={formatXml} disabled={!input.trim() || isProcessing} className="flex-1 gap-2">
                    {isProcessing ? (
                      <>
                        <Sparkles className="w-4 h-4 animate-spin" />
                        处理中...
                      </>
                    ) : (
                      <>
                        <Sparkles className="w-4 h-4" />
                        格式化
                      </>
                    )}
                  </Button>
                  <Button onClick={compactXml} variant="outline" disabled={!input.trim() || isProcessing}>
                    <Minimize2 className="w-4 h-4 mr-1" />
                    压缩
                  </Button>
                </div>
              </CardContent>
            </Card>
            )}

            <Card className={isInputCollapsed ? 'lg:col-span-2' : ''}>
              <CardHeader>
                <div className="flex items-center justify-between">
                  <div>
                    <CardTitle className="text-lg">格式化结果</CardTitle>
                    <CardDescription>格式化后的 XML</CardDescription>
                  </div>
                  {output && (
                    <Button size="sm" variant="outline" onClick={copyToClipboard} className="gap-2">
                      {copied ? (
                        <>
                          <Check className="w-4 h-4" />
                          已复制
                        </>
                      ) : (
                        <>
                          <Copy className="w-4 h-4" />
                          复制
                        </>
                      )}
                    </Button>
                  )}
                </div>
              </CardHeader>
              <CardContent>
                <CodeHighlighter
                  code={output}
                  language="xml"
                  className="w-full"
                  maxHeight="24rem"
                  showLineNumbers={true}
                  wrapLongLines={false}
                />
                {output && (
                  <div className="flex gap-4 mt-4 text-sm text-muted-foreground">
                    <span>字符数: {output.length}</span>
                    <span>行数: {output.split('\n').length}</span>
                  </div>
                )}
              </CardContent>
            </Card>
          </div>

          <Card>
            <CardHeader>
              <CardTitle>使用说明</CardTitle>
            </CardHeader>
            <CardContent className="space-y-2 text-sm text-muted-foreground">
              <p>1. 在左侧输入框中粘贴或输入 XML 数据</p>
              <p>2. 工具会自动验证 XML 有效性，右上角显示验证状态</p>
              <p>3. 选择配置选项：缩进空格数、格式化模式</p>
              <p>4. 点击"格式化"按钮美化 XML，或"压缩"按钮去除空格</p>
              <p>5. 点击"复制"按钮将结果复制到剪贴板</p>
            </CardContent>
          </Card>
        </div>
      </main>
    </div>
  );
}