(function(window) {
    const PdfApp = window.PdfApp = window.PdfApp || {};
    const features = PdfApp.features = PdfApp.features || {};

    features.split = function initSplitFeature() {
        const dropArea = document.getElementById('splitDropArea');
        const fileInput = document.getElementById('split_pdf_file');
        const fileList = document.getElementById('splitFileList');
        const form = document.getElementById('splitPdfForm');
        const submitButton = document.getElementById('splitPdfBtn');
        const loading = document.getElementById('splitLoading');

        if (!dropArea || !fileInput || !fileList || !form || !submitButton || !loading) {
            return;
        }

        let selectedFile = null;

        function displayPdfPageInfo(file, targetElement) {
            const infoDiv = document.createElement('div');
            infoDiv.className = 'pdf-info mt-2';

            const infoText = document.createElement('small');
            infoText.className = 'text-muted';

            const infoIcon = document.createElement('i');
            infoIcon.className = 'fas fa-info-circle';
            infoText.appendChild(infoIcon);
            infoText.appendChild(document.createTextNode(` 文件大小：${PdfApp.formatFileSize(file.size)}`));
            infoDiv.appendChild(infoText);

            const oldInfo = targetElement.querySelector('.pdf-info');
            if (oldInfo) {
                oldInfo.remove();
            }
            targetElement.appendChild(infoDiv);
        }

        function displaySelectedFile() {
            fileList.innerHTML = '';

            if (!selectedFile) {
                submitButton.disabled = true;
                return;
            }

            const fileItem = PdfApp.createFileItem(selectedFile, removeSelectedFile);
            fileList.appendChild(fileItem);
            submitButton.disabled = false;
        }

        function removeSelectedFile() {
            selectedFile = null;
            fileInput.value = '';
            displaySelectedFile();
        }

        fileInput.addEventListener('change', function(event) {
            selectedFile = event.target.files[0] || null;
            displaySelectedFile();
            if (selectedFile) {
                displayPdfPageInfo(selectedFile, fileList);
            }
        });

        PdfApp.bindDragAndDrop(dropArea, function(event) {
            const files = Array.from(event.dataTransfer.files).filter(function(file) {
                return file.type === 'application/pdf';
            });

            if (!files.length) {
                alert('请拖拽PDF文件');
                return;
            }

            selectedFile = files[0];
            fileInput.files = PdfApp.createFileList([selectedFile]);
            displaySelectedFile();
            displayPdfPageInfo(selectedFile, fileList);
        });

        PdfApp.bindRadioToggle('split_type', {
            range: 'rangeOptions',
            group: 'groupOptions',
            extract: 'extractOptions'
        });

        form.addEventListener('submit', function(event) {
            event.preventDefault();

            if (!selectedFile) {
                alert('请选择一个PDF文件');
                return;
            }

            loading.style.display = 'block';
            submitButton.disabled = true;

            const formData = new FormData();
            formData.append('pdf_file', selectedFile);

            const splitType = document.querySelector('input[name="split_type"]:checked').value;
            formData.append('split_type', splitType);

            if (splitType === 'range') {
                const ranges = document.getElementById('ranges').value;
                if (!ranges) {
                    alert('请输入页面范围');
                    loading.style.display = 'none';
                    submitButton.disabled = false;
                    return;
                }
                formData.append('ranges', ranges);
            } else if (splitType === 'group') {
                formData.append('pages_per_group', document.getElementById('pages_per_group').value);
            } else if (splitType === 'extract') {
                const pageNumbers = document.getElementById('page_numbers').value;
                if (!pageNumbers) {
                    alert('请输入要提取的页码');
                    loading.style.display = 'none';
                    submitButton.disabled = false;
                    return;
                }
                formData.append('page_numbers', pageNumbers);
            }

            fetch('/split-pdf', {
                method: 'POST',
                body: formData
            })
                .then(function(response) {
                    if (response.ok) {
                        return response.blob();
                    }
                    return response.json().then(function(err) {
                        throw new Error(err.error || '分割失败');
                    });
                })
                .then(function(blob) {
                    const filename = blob.type === 'application/zip' ? 'split_pdf_files.zip' : 'extracted_page.pdf';
                    PdfApp.downloadBlob(blob, filename);
                    removeSelectedFile();
                })
                .catch(function(error) {
                    console.error('Error:', error);
                    alert('分割失败: ' + error.message);
                })
                .finally(function() {
                    loading.style.display = 'none';
                    submitButton.disabled = false;
                });
        });
    };
})(window);