import { useState, useRef, useEffect } from "react";
import { type MetaFunction, type ActionFunctionArgs } from "@remix-run/node";
import { Form, useNavigation } from "@remix-run/react";
import { UploadArea, type UploadAreaRef } from "~/components/ui/UploadArea";
import { Button } from "~/components/ui/Button";
import { messageService } from "~/components/ui/MessageModal";
import { toastService } from "~/components/ui/Toast";
import crossCheckingUploadStyles from "~/styles/pages/cross-checking-upload.css?url";
import MultiCascader from "~/components/ui/MultiCascader";    
import { SingleDatePicker, links as dateRangePickerLinks } from "~/components/ui/DateRangePicker";
import {
  CaseType,
  CASE_TYPE_TO_TYPE_ID,
  type CrossCheckingUploadedFile,
  generateFileId,
  formatFileSize,
  batchUploadCrossCheckingFiles
} from "~/api/cross-checking/cross-files-upload";
import React from "react"; // Added for React.useState

export const meta: MetaFunction = () => {
    return [
        { title: "交叉评查上传 - 中国烟草AI合同及卷宗审核系统" },
        { name: "description", content: "交叉评查案卷上传和任务创建" }
    ];
};

export const handle = {
    breadcrumb: "交叉评查上传"
};

export function links() {
    return [
        { rel: "stylesheet", href: crossCheckingUploadStyles },
        ...dateRangePickerLinks()
    ];
}

// 步骤枚举
const STEPS = [
    { id: 1, label: "创建任务" },
    { id: 2, label: "创建评查小组" },
    { id: 3, label: "选择卷宗" }
];

// 1. TreeNode类型和MOCK_TREE
export interface TreeNode {
  label: string;
  value: string;
  children?: TreeNode[];
}

const MOCK_TREE: TreeNode[] = [
  {
    label: "梅州市",
    value: "梅州市",
    children: [
      {
        label: "梅江区",
        value: "梅江区",
        children: [
          {
            label: "梅江区烟草局",
            value: "梅江区烟草局",
            children: [
              { label: "张三", value: "梅州市-梅江区-梅江区烟草局-张三" },
              { label: "李四", value: "梅州市-梅江区-梅江区烟草局-李四" }
            ]
          }
        ]
      }
    ]
  },
  {
    label: "揭阳市",
    value: "揭阳市",
    children: [
      {
        label: "榕城区",
        value: "榕城区",
        children: [
          {
            label: "榕城区烟草局",
            value: "榕城区烟草局",
            children: [
              { label: "王五", value: "揭阳市-榕城区-榕城区烟草局-王五" }
            ]
          }
        ]
      }
    ]
  }
];

// 2. TreeMultiSelect递归组件
function getAllLeafValues(node: TreeNode): string[] {
  if (!node.children || node.children.length === 0) return [node.value];
  return node.children.flatMap(getAllLeafValues);
}
function getAllLeafValuesFromTree(tree: TreeNode[]): string[] {
  return tree.flatMap(getAllLeafValues);
}
function isAllChildrenChecked(node: TreeNode, checked: string[]): boolean {
  if (!node.children || node.children.length === 0) return checked.includes(node.value);
  return node.children.every(child => isAllChildrenChecked(child, checked));
}
function isSomeChildrenChecked(node: TreeNode, checked: string[]): boolean {
  if (!node.children || node.children.length === 0) return checked.includes(node.value);
  return node.children.some(child => isSomeChildrenChecked(child, checked));
}
const TreeNodeCheckbox: React.FC<{
  node: TreeNode;
  checked: string[];
  onCheck: (node: TreeNode, checked: boolean) => void;
  level?: number;
}> = ({ node, checked, onCheck, level = 0 }) => {
  const [expanded, setExpanded] = React.useState(true);
  const allChecked = isAllChildrenChecked(node, checked);
  const someChecked = isSomeChildrenChecked(node, checked);
  const isLeaf = !node.children || node.children.length === 0;
  return (
    <div style={{ marginLeft: level * 18 }}>
      <div className="flex items-center">
        {!isLeaf && (
          <span
            className="mr-1 cursor-pointer select-none"
            onClick={() => setExpanded(e => !e)}
            role="button"
            tabIndex={0}
            onKeyDown={e => (e.key === 'Enter' || e.key === ' ') && setExpanded(e => !e)}
            style={{ width: 16, display: "inline-block", textAlign: "center" }}
          >
            {expanded ? "▼" : "▶"}
          </span>
        )}
        <input
          type="checkbox"
          className="form-checkbox"
          checked={allChecked}
          ref={el => { if (el) el.indeterminate = !allChecked && someChecked; }}
          onChange={e => onCheck(node, e.target.checked)}
          id={node.value}
        />
        <label htmlFor={node.value} className="ml-2">{node.label}</label>
      </div>
      {expanded && node.children && (
        <div>
          {node.children.map(child => (
            <TreeNodeCheckbox
              key={child.value}
              node={child}
              checked={checked}
              onCheck={onCheck}
              level={level + 1}
            />
          ))}
        </div>
      )}
    </div>
  );
};
const TreeMultiSelect: React.FC<{
  treeData: TreeNode[];
  value: string[];
  onChange: (v: string[]) => void;
}> = ({ treeData, value, onChange }) => {
  // 递归处理选中/取消
  const handleCheck = (node: TreeNode, checked: boolean) => {
    const leafValues = getAllLeafValues(node);
    let newValue: string[];
    if (checked) {
      newValue = Array.from(new Set([...value, ...leafValues]));
    } else {
      newValue = value.filter(v => !leafValues.includes(v));
    }
    onChange(newValue);
  };
  return (
    <div>
      {treeData.map(node => (
        <TreeNodeCheckbox
          key={node.value}
          node={node}
          checked={value}
          onCheck={handleCheck}
        />
      ))}
    </div>
  );
};

export const action = async ({ request }: ActionFunctionArgs) => {
    const formData = await request.formData();
    const caseType = formData.get("caseType") as string;
    const uploadType = formData.get("uploadType") as string;

    console.log("交叉评查上传:", { caseType, uploadType });

    // 这里可以处理上传后的业务逻辑
    // 例如创建任务记录等
    return Response.json({ success: true, message: "文件上传成功" });
};

export default function CrossCheckingUpload() {
    // 基础状态
    const [caseType, setCaseType] = useState<CaseType>(CaseType.ADMINISTRATIVE_PENALTY);
    // 步骤状态
    const [currentStep, setCurrentStep] = useState(1);
    // 步骤1：任务信息
    const [taskInfo, setTaskInfo] = useState({
        name: '',
        date: '',
        type: '市局交叉评查',
    });
    // 步骤2状态
    const [groupChecked, setGroupChecked] = useState<string[]>([]);

    // 上传配置状态 - 设置默认值
    const [priority] = useState<string>("normal");
    const [documentNumber] = useState<string>("");
    const [remark] = useState<string>("");
    const [isTestDocument] = useState<boolean>(false);

    // 文件管理状态
    const [singleFiles, setSingleFiles] = useState<CrossCheckingUploadedFile[]>([]);
    const [multipleFiles, setMultipleFiles] = useState<CrossCheckingUploadedFile[]>([]);
    const [uploadType, setUploadType] = useState<'none' | 'single' | 'multiple'>('none');
    const [isUploading, setIsUploading] = useState(false);

    // 引用
    const singleUploadRef = useRef<UploadAreaRef>(null);
    const multipleUploadRef = useRef<UploadAreaRef>(null);

    // 获取当前typeId
    const currentTypeId = CASE_TYPE_TO_TYPE_ID[caseType];

    // 处理案卷类型切换
    const handleCaseTypeChange = (type: CaseType) => {
        if (isUploading) {
            toastService.warning("上传进行中，无法切换案卷类型");
            return;
        }

        setCaseType(type);
        // 清空已选择的文件和重置上传方式
        clearAllFiles();
        console.log("案卷类型切换为:", type, "typeId:", CASE_TYPE_TO_TYPE_ID[type]);
    };

    // 清空所有文件
    const clearAllFiles = () => {
        setSingleFiles([]);
        setMultipleFiles([]);
        setUploadType('none');
        // 重置文件输入框
        singleUploadRef.current?.resetFileInput();
        multipleUploadRef.current?.resetFileInput();
    };

    // 处理单案件文件选择
    const handleSingleFilesSelected = (files: FileList) => {
        if (uploadType === 'multiple') {
            toastService.warning("已选择多案件导入方式，无法选择单案件文件");
            return;
        }

        const validFiles: CrossCheckingUploadedFile[] = [];
        let hasInvalidFiles = false;

        Array.from(files).forEach(file => {
            if (file.type === 'application/pdf' || file.name.toLowerCase().endsWith('.pdf')) {
                validFiles.push({
                    id: generateFileId(),
                    file,
                    name: file.name,
                    size: file.size,
                    type: file.type,
                    uploadType: 'single'
                });
            } else {
                hasInvalidFiles = true;
            }
        });

        if (hasInvalidFiles) {
            messageService.error('只能上传PDF格式的文件', {
                title: '文件类型错误',
                confirmText: '确定',
            });
        }

        if (validFiles.length > 0) {
            setSingleFiles(prev => [...prev, ...validFiles]);
            setUploadType('single');
            console.log("选择单案件文件:", validFiles.length, "个");
        }
    };

    // 处理多案件文件选择
    const handleMultipleFilesSelected = (files: FileList) => {
        if (uploadType === 'single') {
            toastService.warning("已选择单案件导入方式，无法选择多案件文件");
            return;
        }

        const validFiles: CrossCheckingUploadedFile[] = [];
        let hasInvalidFiles = false;

        Array.from(files).forEach(file => {
            const isZip = file.type === 'application/zip' || 
                         file.type === 'application/x-zip-compressed' || 
                         file.name.toLowerCase().endsWith('.zip');
            const isRar = file.type === 'application/x-rar-compressed' || 
                         file.name.toLowerCase().endsWith('.rar');
            const is7z = file.type === 'application/x-7z-compressed' || 
                         file.name.toLowerCase().endsWith('.7z');
            const isTar = file.type === 'application/x-tar' || 
                         file.name.toLowerCase().endsWith('.tar');
            
            if (isZip || isRar || is7z || isTar) {
                validFiles.push({
                    id: generateFileId(),
                    file,
                    name: file.name,
                    size: file.size,
                    type: file.type,
                    uploadType: 'multiple'
                });
            } else {
                hasInvalidFiles = true;
            }
        });

        if (hasInvalidFiles) {
            messageService.error('只能上传ZIP或RAR格式的压缩文件', {
                title: '文件类型错误',
                confirmText: '确定',
            });
        }

        if (validFiles.length > 0) {
            setMultipleFiles(prev => [...prev, ...validFiles]);
            setUploadType('multiple');
            console.log("选择多案件文件:", validFiles.length, "个");
        }
    };

    // 删除单个文件
    const handleRemoveFile = (fileId: string, type: 'single' | 'multiple') => {
        if (isUploading) {
            toastService.warning("上传进行中，无法删除文件");
            return;
        }

        if (type === 'single') {
            setSingleFiles(prev => {
                const newFiles = prev.filter(f => f.id !== fileId);
                if (newFiles.length === 0) {
                    setUploadType('none');
                    singleUploadRef.current?.resetFileInput();
                }
                return newFiles;
            });
        } else {
            setMultipleFiles(prev => {
                const newFiles = prev.filter(f => f.id !== fileId);
                if (newFiles.length === 0) {
                    setUploadType('none');
                    multipleUploadRef.current?.resetFileInput();
                }
                return newFiles;
            });
        }
    };

    // 清空文件列表
    const handleClearFiles = (type: 'single' | 'multiple') => {
        if (isUploading) {
            toastService.warning("上传进行中，无法清空文件");
            return;
        }

        if (type === 'single') {
            setSingleFiles([]);
            singleUploadRef.current?.resetFileInput();
        } else {
            setMultipleFiles([]);
            multipleUploadRef.current?.resetFileInput();
        }
        setUploadType('none');
    };

    // 处理完成上传
    const handleCompleteUpload = async () => {
        const filesToUpload = uploadType === 'single' ? singleFiles : multipleFiles;
        
        if (filesToUpload.length === 0) {
            toastService.error("请先选择要上传的文件");
            return;
        }

        setIsUploading(true);
        
        try {
            console.log("开始批量上传文件:", filesToUpload.length, "个，案卷类型:", caseType, "typeId:", currentTypeId);
            
            const result = await batchUploadCrossCheckingFiles(
                filesToUpload,
                currentTypeId,
                priority,
                documentNumber,
                remark,
                isTestDocument
            );

            const { successes, failures } = result;

            if (failures.length === 0) {
                // 全部成功
                toastService.success(`成功上传 ${successes.length} 个文件`);
                messageService.success(`文件上传完成！成功上传 ${successes.length} 个文件，现在可以进行下一步操作。`, {
                    title: '上传成功',
                    confirmText: '确定',
                    onConfirm: () => {
                        // 清空文件列表
                        clearAllFiles();
                    }
                });
            } else if (successes.length === 0) {
                // 全部失败
                toastService.error(`文件上传失败，共 ${failures.length} 个文件上传失败`);
                messageService.error(`所有文件上传失败。失败原因：${failures[0].error}`, {
                    title: '上传失败',
                    confirmText: '确定',
                });
            } else {
                // 部分成功
                toastService.warning(`部分文件上传成功：成功 ${successes.length} 个，失败 ${failures.length} 个`);
                messageService.warning(
                    `部分文件上传完成：\n成功：${successes.length} 个文件\n失败：${failures.length} 个文件\n\n失败文件：\n${failures.map(f => `${f.file.name}: ${f.error}`).join('\n')}`,
                    {
                        title: '部分上传成功',
                        confirmText: '确定',
                    }
                );
            }

        } catch (error) {
            console.error("批量上传失败:", error);
            toastService.error("文件上传过程中发生错误");
            messageService.error(`文件上传失败：${error instanceof Error ? error.message : '未知错误'}`, {
                title: '上传失败',
                confirmText: '确定',
            });
        } finally {
            setIsUploading(false);
        }
    };

    // 步骤切换
    const handleNext = () => setCurrentStep((s) => Math.min(s + 1, 3));
    const handlePrev = () => setCurrentStep((s) => Math.max(s - 1, 1));

    // 步骤1表单校验
    const canNextStep1 = taskInfo.name.trim() && taskInfo.date.trim() && taskInfo.type.trim();
    // 小组多选逻辑
    useEffect(() => {
        setGroupChecked(getAllLeafValuesFromTree(MOCK_TREE));
    }, []);

    // 检查是否可以完成
    const canComplete = (singleFiles.length > 0 || multipleFiles.length > 0) && !isUploading;
    const navigation = useNavigation();
    const isSubmitting = navigation.state === "submitting";

    return (
        <div className="min-h-screen bg-gray-50 py-8">
            <div className="max-w-6xl mx-auto px-4">
                {/* 步骤指示器 */}
                <div className="steps-indicator">
                    {STEPS.map((step) => (
                        <div
                            key={step.id}
                            className={`step-item ${step.id < currentStep ? 'completed' : ''}`}
                        >
                            <div className={`step-circle ${step.id === currentStep ? 'active' : 'inactive'}`}>{step.id}</div>
                            <div className="step-label">{step.label}</div>
                        </div>
                    ))}
                </div>

                {/* 案卷类型选择器 */}
                <div className="case-type-selector">
                    <div className="case-type-options">
                        <button
                            type="button"
                            className={`case-type-option ${caseType === CaseType.ADMINISTRATIVE_PENALTY ? 'active' : 'inactive'}`}
                            onClick={() => handleCaseTypeChange(CaseType.ADMINISTRATIVE_PENALTY)}
                            disabled={isUploading}
                        >
                            行政处罚
                        </button>
                        <button
                            type="button"
                            className={`case-type-option ${caseType === CaseType.ADMINISTRATIVE_PERMIT ? 'active' : 'inactive'}`}
                            onClick={() => handleCaseTypeChange(CaseType.ADMINISTRATIVE_PERMIT)}
                            disabled={isUploading}
                        >
                            行政许可
                        </button>
                    </div>
                </div>

                {/* 步骤1：创建任务 */}
                {currentStep === 1 && (
                    <div className="step-form-container">
                        <div className="form-group">
                            <label htmlFor="task-name">任务名称<span className="text-red-500">*</span></label>
                            <input
                                id="task-name"
                                className="form-input"
                                value={taskInfo.name}
                                onChange={e => setTaskInfo({ ...taskInfo, name: e.target.value })}
                                placeholder="请输入任务名称"
                            />
                        </div>
                        <div className="form-group">
                            <label className="form-label required">评查时间</label>
                            <SingleDatePicker
                                date={taskInfo.date}
                                onDateChange={(value) => setTaskInfo({ ...taskInfo, date: value })}
                                className="w-full"
                                id="task-date"
                                placeholder="请选择日期"
                            />
                        </div>
                        <div className="form-group">
                            <label htmlFor="task-type">任务类型</label>
                            <input
                                id="task-type"
                                className="form-input"
                                value={taskInfo.type}
                                onChange={e => setTaskInfo({ ...taskInfo, type: e.target.value })}
                                placeholder="请输入任务类型"
                            />
                        </div>
                        <div className="flex justify-center mt-8">
                            <Button type="primary" disabled={!canNextStep1} onClick={handleNext}>下一步</Button>
                        </div>
                    </div>
                )}

                {/* 步骤2：创建评查小组 */}
                {currentStep === 2 && (
                    <>
                        <div className="step-form-container flex flex-row justify-center items-start gap-12">
                            {/* 左侧树状多选 */}
                            <div style={{ minWidth: 260 }}>
                                <div className="form-group">
                                    <label className="form-label required">评查小组</label>
                                    <MultiCascader
                                        options={MOCK_TREE}
                                        placeholder="请选择评查小组"
                                        defaultValue={groupChecked}
                                        onChange={(values: string[]) => {
                                            setGroupChecked(values);
                                        }}
                                    />
                                </div>
                            </div>
                            {/* 右侧预留区域 */}
                            <div style={{ minWidth: 320, minHeight: 200, background: '#fff', border: '1.5px solid #e5e7eb', borderRadius: 8 }}></div>
                        </div>
                        <div className="flex justify-center mt-8 space-x-4">
                            <Button type="default" onClick={handlePrev}>上一步</Button>
                            <Button type="primary" disabled={groupChecked.length === 0} onClick={handleNext}>下一步</Button>
                        </div>
                    </>
                )}

                {/* 步骤3：原有上传区域 */}
                {currentStep === 3 && (
                    <>
                        {/* 文件上传区域 */}
                        <Form method="post" encType="multipart/form-data">
                            <input type="hidden" name="caseType" value={caseType} />
                            <input type="hidden" name="uploadType" value={uploadType} />
                            
                            <div className="upload-section">
                                {/* 单案件导入 */}
                                <div className="upload-item">
                                    <div className="upload-item-header">
                                        <i className="upload-item-icon ri-file-text-line"></i>
                                        <span>单案件导入</span>
                                        {uploadType === 'single' && singleFiles.length > 0 && (
                                            <Button
                                                type="default"
                                                size="small"
                                                icon="ri-delete-bin-line"
                                                onClick={() => handleClearFiles('single')}
                                                disabled={isUploading}
                                            >
                                                清空
                                            </Button>
                                        )}
                                    </div>
                                    <UploadArea
                                        ref={singleUploadRef}
                                        onFilesSelected={handleSingleFilesSelected}
                                        className="custom-upload-area"
                                        accept=".pdf"
                                        multiple={true}
                                        icon="ri-file-upload-line"
                                        buttonText="选择文件"
                                        mainText="点击或拖拽文件到此区域上传"
                                        tipText={
                                            <div className="upload-tip-error">
                                                请上传案件相关PDF文件
                                            </div>
                                        }
                                        disabled={uploadType === 'multiple' || isUploading}
                                    />
                                    
                                    {/* 单案件文件列表 */}
                                    {singleFiles.length > 0 && (
                                        <div className="mt-4 space-y-2">
                                            <div className="text-sm font-medium text-gray-700">
                                                已选择 {singleFiles.length} 个文件:
                                            </div>
                                            <div className="max-h-32 overflow-y-auto space-y-1">
                                                {singleFiles.map((file) => (
                                                    <div key={file.id} className="flex items-center justify-between bg-gray-50 p-2 rounded">
                                                        <div className="flex items-center space-x-2 flex-1 min-w-0">
                                                            <i className="ri-file-pdf-line text-red-500"></i>
                                                            <span className="text-sm truncate">{file.name}</span>
                                                            <span className="text-xs text-gray-500">{formatFileSize(file.size)}</span>
                                                        </div>
                                                        <button
                                                            type="button"
                                                            onClick={() => handleRemoveFile(file.id, 'single')}
                                                            className="text-red-500 hover:text-red-700 p-1"
                                                            disabled={isUploading}
                                                        >
                                                            <i className="ri-close-line"></i>
                                                        </button>
                                                    </div>
                                                ))}
                                            </div>
                                        </div>
                                    )}
                                </div>

                                {/* 多案件导入 */}
                                <div className="upload-item">
                                    <div className="upload-item-header">
                                        <i className="upload-item-icon ri-file-list-line"></i>
                                        <span>多案件导入</span>
                                        {uploadType === 'multiple' && multipleFiles.length > 0 && (
                                            <Button
                                                type="default"
                                                size="small"
                                                icon="ri-delete-bin-line"
                                                onClick={() => handleClearFiles('multiple')}
                                                disabled={isUploading}
                                            >
                                                清空
                                            </Button>
                                        )}
                                    </div>
                                    <UploadArea
                                        ref={multipleUploadRef}
                                        onFilesSelected={handleMultipleFilesSelected}
                                        className="custom-upload-area"
                                        accept=".zip,.rar,.7z,.tar"
                                        multiple={false}
                                        icon="ri-folder-zip-line"
                                        buttonText="选择文件"
                                        mainText="点击或拖拽文件到此区域上传"
                                        tipText={
                                            <div className="upload-tip-error">
                                                请上传多个案件作为压缩包zip、rar、7z、tar文件
                                            </div>
                                        }
                                        disabled={uploadType === 'single' || isUploading}
                                    />

                                    {/* 多案件文件列表 */}
                                    {multipleFiles.length > 0 && (
                                        <div className="mt-4 space-y-2">
                                            <div className="text-sm font-medium text-gray-700">
                                                已选择 {multipleFiles.length} 个压缩包:
                                            </div>
                                            <div className="max-h-32 overflow-y-auto space-y-1">
                                                {multipleFiles.map((file) => (
                                                    <div key={file.id} className="flex items-center justify-between bg-gray-50 p-2 rounded">
                                                        <div className="flex items-center space-x-2 flex-1 min-w-0">
                                                            <i className="ri-folder-zip-line text-orange-500"></i>
                                                            <span className="text-sm truncate">{file.name}</span>
                                                            <span className="text-xs text-gray-500">{formatFileSize(file.size)}</span>
                                                        </div>
                                                        <button
                                                            type="button"
                                                            onClick={() => handleRemoveFile(file.id, 'multiple')}
                                                            className="text-red-500 hover:text-red-700 p-1"
                                                            disabled={isUploading}
                                                        >
                                                            <i className="ri-close-line"></i>
                                                        </button>
                                                    </div>
                                                ))}
                                            </div>
                                        </div>
                                    )}
                                </div>
                            </div>

                            {/* 完成按钮 */}
                            <div className="complete-button-container">
                                <button
                                    type="button"
                                    className="complete-button"
                                    disabled={!canComplete}
                                    onClick={handleCompleteUpload}
                                >
                                    {isUploading || isSubmitting ? (
                                        <>
                                            <i className="ri-loader-4-line animate-spin mr-2"></i>
                                            上传中...
                                        </>
                                    ) : (
                                        "完成"
                                    )}
                                </button>
                            </div>
                        </Form>

                        {/* 文件选择状态提示 */}
                        {!canComplete && !isUploading && (
                            <div className="text-center mt-4 text-gray-500 text-sm">
                                请至少选择一种导入方式的文件
                            </div>
                        )}

                        {/* 上传进度提示 */}
                        {isUploading && (
                            <div className="text-center mt-4">
                                <div className="bg-blue-50 p-4 rounded-md border border-blue-100">
                                    <div className="flex items-center justify-center text-blue-800 mb-2">
                                        <i className="ri-loader-4-line ri-spin  animate-spin text-xl mr-2"></i>
                                        <span className="font-medium">正在上传文件...</span>
                                    </div>
                                    <p className="text-sm text-blue-700">
                                        正在上传 {uploadType === 'single' ? singleFiles.length : multipleFiles.length} 个文件，请稍候
                                    </p>
                                </div>
                            </div>
                        )}
                    </>
                )}
            </div>
        </div>
    );
}