import {
    ArrowLeftOutlined,
    CheckCircleOutlined,
    DeleteOutlined,
    ExclamationCircleOutlined,
    FileTextOutlined,
    InboxOutlined,
    LoadingOutlined,
    QuestionCircleOutlined,
} from '@ant-design/icons';
import type { UploadFile } from 'antd';
import {
    Button,
    Card,
    Checkbox,
    Divider,
    Empty,
    Input,
    InputNumber,
    Progress,
    Select,
    Spin,
    Tooltip,
    Upload,
    message,
} from 'antd';
import { useEffect, useState } from 'react';
import type { Segment } from '~/api/dify-dataset/type';
import { useDocumentUpload } from '~/hooks/dify-dataset-manager/document-upload';
import type { DocumentUploadProps, UploadedDocument } from '~/types/dify-dataset-manager/document-upload';
import { SUPPORTED_ACCEPT, SUPPORTED_FILE_EXTENSIONS, SUPPORTED_FORMATS } from '~/types/dify-dataset-manager/document-upload';

const { Dragger } = Upload;
const MAX_FILE_SIZE_MB = 15;

/**
 * 文档上传组件
 * 支持多文件上传，两步流程：选择文件 → 上传并配置分段
 */
export default function DocumentUpload({
    datasetId,
    onClose,
    onSuccess,
}: DocumentUploadProps) {
    const {
        // 状态
        step,
        fileList,
        uploadedDocuments,
        currentSettings,
        previewLoading,

        // 方法
        handleFileChange,
        handleRemoveFile,
        handleNextStep,
        handleDocumentChange,
        handleReprocess,
        handlePrevStep,
        handleGoToDocuments,
        updateCurrentSettings,

        // 计算属性方法
        getCurrentDocument,
        getCurrentProgress,
        getStatusText,
        isCurrentDocProcessing,
        getCompletionStats,
    } = useDocumentUpload(datasetId, onClose, onSuccess);

    const selectedFiles = fileList.filter((f: UploadFile) => f.originFileObj).map((f: UploadFile) => f.originFileObj as File);

    // 平滑进度条逻辑
    const [displayPercent, setDisplayPercent] = useState(0);
    const targetPercent = getCurrentProgress();

    useEffect(() => {
        if (targetPercent > displayPercent) {
            // 如果目标进度大于当前显示进度，启动动画
            const diff = targetPercent - displayPercent;
            // 动态步长：差距越大跑得越快，但最小步长为1
            const step = Math.max(1, Math.ceil(diff / 10));

            const timer = requestAnimationFrame(() => {
                setDisplayPercent(prev => Math.min(targetPercent, prev + step));
            });

            return () => cancelAnimationFrame(timer);
        } else if (targetPercent < displayPercent && targetPercent === 0) {
            // 如果目标重置为0（例如重新开始），立即重置
            setDisplayPercent(0);
        }
    }, [targetPercent, displayPercent]);

    /**
     * 渲染步骤指示器（两步流程）
     */
    const renderSteps = () => (
        <div className="upload-steps">
            <div className={`step-item ${step === 1 ? 'active' : ''} ${step > 1 ? 'completed' : ''}`}>
                <span className="step-number">1</span>
                <span className="step-title">选择数据源</span>
            </div>
            <div className={`step-divider ${step > 1 ? 'completed' : ''}`}></div>
            <div className={`step-item ${step === 2 ? 'active' : ''}`}>
                <span className="step-number">2</span>
                <span className="step-title">文本分段与清洗</span>
            </div>
        </div>
    );

    /**
     * 渲染第一步：选择文件（支持多文件）
     */
    const renderStep1 = () => (
        <div className="upload-step-content step1">
            <h2 className="step-heading">上传文本文件</h2>
            <p className="step-description">
                文档需上传至知识智能理解法治知识库，广东烟草智能理解将按照于知识库，你可以在聊后指数文档所据案中检索它
            </p>

            <div className="file-drop-zone">
                <Dragger
                    fileList={fileList}
                    onChange={handleFileChange}
                    beforeUpload={(file) => {
                        const lowerName = file.name.toLowerCase();
                        const isSupported = SUPPORTED_FILE_EXTENSIONS.some((ext) => lowerName.endsWith(ext));
                        if (!isSupported) {
                            message.error(`仅支持上传 ${SUPPORTED_FORMATS} 格式的文件`);
                            return Upload.LIST_IGNORE;
                        }

                        const isWithinLimit = file.size / 1024 / 1024 <= MAX_FILE_SIZE_MB;
                        if (!isWithinLimit) {
                            message.error(`单个文件大小不能超过 ${MAX_FILE_SIZE_MB}MB`);
                            return Upload.LIST_IGNORE;
                        }

                        return false;
                    }}
                    multiple={true}
                    accept={SUPPORTED_ACCEPT}
                    showUploadList={false}
                >
                    <p className="ant-upload-drag-icon">
                        <InboxOutlined />
                    </p>
                    <p className="ant-upload-text">拖拽文件或至此，或者 <span className="upload-link">选择文件</span></p>
                    <p className="ant-upload-hint">
                        已支持 {SUPPORTED_FORMATS}，每个文件不超过 15MB。支持批量上传多个文件。
                    </p>
                </Dragger>
            </div>

            {/* 已选文件列表 */}
            {selectedFiles.length > 0 && (
                <div className="selected-files-section">
                    <h3 className="section-subtitle">嵌入已就绪 ({selectedFiles.length} 个文件)</h3>
                    <div className="selected-files-list">
                        {fileList.map((file: UploadFile) => (
                            <div key={file.uid} className="selected-file-item">
                                <FileTextOutlined className="file-icon" />
                                <div className="file-info">
                                    <span className="file-name">{file.name}</span>
                                    <span className="file-size">
                                        {file.originFileObj
                                            ? `${file.originFileObj.type?.split('/')[1]?.toUpperCase() || 'FILE'}，${(file.originFileObj.size / 1024 / 1024).toFixed(2)}MB`
                                            : ''}
                                    </span>
                                </div>
                                <Button
                                    type="text"
                                    icon={<DeleteOutlined />}
                                    onClick={() => handleRemoveFile(file)}
                                    className="remove-file-btn"
                                />
                            </div>
                        ))}
                    </div>
                </div>
            )}

            <div className="step-actions">
                <Button
                    type="primary"
                    onClick={handleNextStep}
                    disabled={selectedFiles.length === 0}
                    className="next-btn"
                >
                    下一步 →
                </Button>
            </div>
        </div>
    );

    /**
     * 渲染第二步：分段配置与预览
     * 左侧始终显示配置面板，右侧预览框内显示进度或分段内容
     */
    const renderStep2 = () => {
        const currentDoc = getCurrentDocument();
        const isProcessing = isCurrentDocProcessing();
        const stats = getCompletionStats();

        return (
            <div className="upload-step-content step2">
                {/* 分段配置与预览 */}
                <div className="document-detail-content">
                    {/* 左侧设置区域 */}
                    <div className="settings-panel">
                        <div className="settings-section">
                            <h3 className="section-title">分段设置</h3>

                            {/* 分段标识符 */}
                            <div className="setting-item">
                                <label className="setting-label">
                                    分段标识符
                                    <Tooltip title="系统会在遇到指定分隔符时自动分段，默认值为 \n\n（按段落分段）">
                                        <QuestionCircleOutlined className="help-icon" />
                                    </Tooltip>
                                </label>
                                <Input
                                    value={currentSettings.separator}
                                    onChange={(e) => updateCurrentSettings('separator', e.target.value)}
                                    placeholder="\n\n"
                                    className="setting-input"
                                    disabled={isProcessing}
                                />
                            </div>

                            {/* 分段最大长度 */}
                            <div className="setting-item">
                                <label className="setting-label">
                                    分段最大长度
                                    <Tooltip title="指定每个分段允许的最大字符数（100-4000），超过此限制系统会强制分段">
                                        <QuestionCircleOutlined className="help-icon" />
                                    </Tooltip>
                                </label>
                                <div className="setting-input-with-suffix">
                                    <InputNumber
                                        value={currentSettings.maxTokens}
                                        onChange={(value) => updateCurrentSettings('maxTokens', value || 1024)}
                                        min={100}
                                        max={4000}
                                        className="setting-input-number"
                                        disabled={isProcessing}
                                    />
                                    <span className="input-suffix">characters</span>
                                </div>
                            </div>

                            {/* 分段重叠长度 */}
                            <div className="setting-item">
                                <label className="setting-label">
                                    分段重叠长度
                                    <Tooltip title="设置分段之间的重叠长度可以保留分段之间的语义关系，提升召回效果建议设置为最大分段长度的10%-25%">
                                        <QuestionCircleOutlined className="help-icon" />
                                    </Tooltip>
                                </label>
                                <div className="setting-input-with-suffix">
                                    <InputNumber
                                        value={currentSettings.chunkOverlap}
                                        onChange={(value) => updateCurrentSettings('chunkOverlap', value || 50)}
                                        min={0}
                                        max={500}
                                        className="setting-input-number"
                                        disabled={isProcessing}
                                    />
                                    <span className="input-suffix">characters</span>
                                </div>
                            </div>
                        </div>

                        <Divider />

                        {/* 文本预处理规则 */}
                        <div className="settings-section">
                            <h3 className="section-title">文本预处理规则</h3>
                            <div className="checkbox-group">
                                <Checkbox
                                    checked={currentSettings.removeExtraSpaces}
                                    onChange={(e) => updateCurrentSettings('removeExtraSpaces', e.target.checked)}
                                    disabled={isProcessing}
                                >
                                    替换掉连续的空格、换行符和制表符
                                </Checkbox>
                                <Checkbox
                                    checked={currentSettings.removeUrlsEmails}
                                    onChange={(e) => updateCurrentSettings('removeUrlsEmails', e.target.checked)}
                                    disabled={isProcessing}
                                >
                                    删除所有 URL 和电子邮件地址
                                </Checkbox>
                            </div>
                        </div>

                        <Divider />

                        {/* 索引方式 */}
                        <div className="settings-section">
                            <h3 className="section-title">索引方式</h3>
                            <div className="index-options">
                                <div
                                    className={`index-option ${currentSettings.indexingTechnique === 'high_quality' ? 'active' : ''} ${isProcessing ? 'disabled' : ''}`}
                                    onClick={() => !isProcessing && updateCurrentSettings('indexingTechnique', 'high_quality')}
                                >
                                    <span className="option-radio"></span>
                                    <span className="option-label">高质量</span>
                                    <span className="option-badge recommended">推荐</span>
                                </div>
                                <div
                                    className={`index-option ${currentSettings.indexingTechnique === 'economy' ? 'active' : ''} ${isProcessing ? 'disabled' : ''}`}
                                    onClick={() => !isProcessing && updateCurrentSettings('indexingTechnique', 'economy')}
                                >
                                    <span className="option-radio"></span>
                                    <span className="option-label">经济</span>
                                </div>
                            </div>
                        </div>

                        {/* 操作按钮 */}
                        <div className="settings-actions">
                            <Button onClick={handlePrevStep} disabled={isProcessing}>
                                <ArrowLeftOutlined /> 上一步
                            </Button>
                            <Button
                                type="primary"
                                onClick={handleReprocess}
                                loading={isProcessing}
                                disabled={isProcessing || !currentDoc?.documentId}
                            >
                                更新嵌入配置
                            </Button>
                        </div>
                    </div>

                    {/* 右侧预览区域 */}
                    <div className="preview-panel">
                        <Card
                            title={
                                <div className="preview-header">
                                    <span>预览</span>
                                    {uploadedDocuments.length > 0 && (
                                        <>
                                            <Select
                                                value={currentDoc?.documentId || currentDoc?.file.name}
                                                style={{ width: 500 }}
                                                onChange={handleDocumentChange}
                                                options={uploadedDocuments.map((doc: UploadedDocument) => ({
                                                    value: doc.documentId || doc.file.name,
                                                    label: (
                                                        <span className="file-select-option">
                                                            {doc.stage === 'completed' && <CheckCircleOutlined style={{ color: '#52c41a', marginRight: 4 }} />}
                                                            {(doc.stage === 'uploading' || doc.stage === 'indexing') && <LoadingOutlined style={{ color: '#00684a', marginRight: 4 }} />}
                                                            {doc.stage === 'error' && <ExclamationCircleOutlined style={{ color: '#ff4d4f', marginRight: 4 }} />}
                                                            {doc.file.name}
                                                        </span>
                                                    ),
                                                }))}
                                            />
                                            {!isProcessing && currentDoc?.segments && (
                                                <span className="segment-count">
                                                    {currentDoc.segments.length} 段块
                                                </span>
                                            )}
                                        </>
                                    )}
                                </div>
                            }
                            className="preview-card"
                        >
                            {/* 处理进度（在预览框内显示） */}
                            {isProcessing ? (
                                <div className="preview-processing">
                                    <div className="processing-file">
                                        <FileTextOutlined className="file-icon" />
                                        <span className="file-name">{currentDoc?.file.name}</span>
                                        <LoadingOutlined className="status-icon loading" />
                                    </div>
                                    <Progress
                                        percent={displayPercent}
                                        status="active"
                                        strokeColor={{
                                            '0%': '#00684a',
                                            '100%': '#52c41a',
                                        }}
                                    />
                                    <div className="status-text">{getStatusText()}</div>
                                </div>
                            ) : currentDoc?.stage === 'error' ? (
                                <div className="preview-error">
                                    <ExclamationCircleOutlined className="error-icon" />
                                    <div className="error-text">{currentDoc.error || '处理失败'}</div>
                                </div>
                            ) : previewLoading ? (
                                <div className="preview-loading">
                                    <Spin size="large" />
                                    <div className="loading-text">加载中...</div>
                                </div>
                            ) : (currentDoc?.segments?.length ?? 0) === 0 ? (
                                <div className="preview-empty">
                                    <Empty description="等待处理完成后显示分段预览" />
                                </div>
                            ) : (
                                <div className="preview-segments">
                                    {currentDoc?.segments.map((segment: Segment, index: number) => (
                                        <div key={segment.id} className="segment-item">
                                            <div className="segment-header">
                                                <span className="segment-index">#{index + 1}</span>
                                                <span className="segment-chars">
                                                    {segment.word_count} 字符
                                                </span>
                                            </div>
                                            <div className="segment-content">
                                                {segment.content}
                                            </div>
                                        </div>
                                    ))}
                                </div>
                            )}
                        </Card>
                    </div>
                </div>

                {/* 完成状态底部操作 */}
                {stats.completed > 0 && (
                    <div className="completion-actions">
                        <span className="completion-stats">
                            {stats.completed}/{stats.total} 个文档处理完成
                        </span>
                        <Button type="primary" onClick={handleGoToDocuments}>
                            前往知识库
                        </Button>
                    </div>
                )}
            </div>
        );
    };

    return (
        <div className="document-upload-page">
            {/* 页面头部 */}
            <div className="upload-header">
                <Button
                    type="text"
                    icon={<ArrowLeftOutlined />}
                    onClick={onClose}
                    className="back-btn"
                >
                    知识库
                </Button>
                {renderSteps()}
            </div>

            {/* 内容区域 */}
            <div className="upload-content">
                {step === 1 && renderStep1()}
                {step === 2 && renderStep2()}
            </div>
        </div>
    );
}