src/js/logic/edit-attachments-page.ts

import { EditAttachmentState, AttachmentInfo } from '@/types';
import { showLoader, hideLoader, showAlert } from '../ui.js';
import { downloadFile, formatBytes } from '../utils/helpers.js';
import { createIcons, icons } from 'lucide';
import { isCpdfAvailable } from '../utils/cpdf-helper.js';
import {
  showWasmRequiredDialog,
  WasmProvider,
} from '../utils/wasm-provider.js';

const worker = new Worker(
  import.meta.env.BASE_URL + 'workers/edit-attachments.worker.js'
);

const pageState: EditAttachmentState = {
  file: null,
  allAttachments: [],
  attachmentsToRemove: new Set(),
};

function resetState() {
  pageState.file = null;
  pageState.allAttachments = [];
  pageState.attachmentsToRemove.clear();

  const fileDisplayArea = document.getElementById('file-display-area');
  if (fileDisplayArea) fileDisplayArea.innerHTML = '';

  const toolOptions = document.getElementById('tool-options');
  if (toolOptions) toolOptions.classList.add('hidden');

  const attachmentsList = document.getElementById('attachments-list');
  if (attachmentsList) attachmentsList.innerHTML = '';

  const processBtn = document.getElementById('process-btn');
  if (processBtn) processBtn.classList.add('hidden');

  const fileInput = document.getElementById('file-input') as HTMLInputElement;
  if (fileInput) fileInput.value = '';
}

worker.onmessage = function (e) {
  const data = e.data;

  if (data.status === 'success' && data.attachments !== undefined) {
    pageState.allAttachments = data.attachments.map(function (att: any) {
      return {
        ...att,
        data: new Uint8Array(att.data),
      };
    });

    displayAttachments(data.attachments);
    hideLoader();
  } else if (data.status === 'success' && data.modifiedPDF !== undefined) {
    hideLoader();

    const originalName =
      pageState.file?.name.replace(/\.pdf$/i, '') || 'document';
    downloadFile(
      new Blob([new Uint8Array(data.modifiedPDF)], { type: 'application/pdf' }),
      `${originalName}_edited.pdf`
    );

    showAlert(
      'Success',
      'Attachments updated successfully!',
      'success',
      function () {
        resetState();
      }
    );
  } else if (data.status === 'error') {
    hideLoader();
    showAlert('Error', data.message || 'Unknown error occurred.');
  }
};

worker.onerror = function (error) {
  hideLoader();
  console.error('Worker error:', error);
  showAlert('Error', 'Worker error occurred. Check console for details.');
};

function displayAttachments(attachments: AttachmentInfo[]) {
  const attachmentsList = document.getElementById('attachments-list');
  const processBtn = document.getElementById('process-btn');

  if (!attachmentsList) return;

  attachmentsList.innerHTML = '';

  if (attachments.length === 0) {
    const noAttachments = document.createElement('p');
    noAttachments.className = 'text-gray-400 text-center py-4';
    noAttachments.textContent = 'No attachments found in this PDF.';
    attachmentsList.appendChild(noAttachments);
    return;
  }

  // Controls container
  const controlsContainer = document.createElement('div');
  controlsContainer.className = 'attachments-controls mb-4 flex justify-end';

  const removeAllBtn = document.createElement('button');
  removeAllBtn.className =
    'bg-red-500 hover:bg-red-600 text-white px-4 py-2 rounded text-sm';
  removeAllBtn.textContent = 'Remove All Attachments';
  removeAllBtn.onclick = function () {
    if (pageState.allAttachments.length === 0) return;

    const allSelected = pageState.allAttachments.every(function (attachment) {
      return pageState.attachmentsToRemove.has(attachment.index);
    });

    if (allSelected) {
      pageState.allAttachments.forEach(function (attachment) {
        pageState.attachmentsToRemove.delete(attachment.index);
        const element = document.querySelector(
          `[data-attachment-index="${attachment.index}"]`
        );
        if (element) {
          element.classList.remove('opacity-50', 'line-through');
          const btn = element.querySelector('button');
          if (btn) {
            btn.classList.remove('bg-gray-600');
            btn.classList.add('bg-red-600');
          }
        }
      });
      removeAllBtn.textContent = 'Remove All Attachments';
    } else {
      pageState.allAttachments.forEach(function (attachment) {
        pageState.attachmentsToRemove.add(attachment.index);
        const element = document.querySelector(
          `[data-attachment-index="${attachment.index}"]`
        );
        if (element) {
          element.classList.add('opacity-50', 'line-through');
          const btn = element.querySelector('button');
          if (btn) {
            btn.classList.add('bg-gray-600');
            btn.classList.remove('bg-red-600');
          }
        }
      });
      removeAllBtn.textContent = 'Deselect All';
    }
  };

  controlsContainer.appendChild(removeAllBtn);
  attachmentsList.appendChild(controlsContainer);

  // Attachment items
  for (const attachment of attachments) {
    const attachmentDiv = document.createElement('div');
    attachmentDiv.className =
      'flex items-center justify-between p-3 bg-gray-800 rounded-lg border border-gray-700';
    attachmentDiv.dataset.attachmentIndex = attachment.index.toString();

    const infoDiv = document.createElement('div');
    infoDiv.className = 'flex-1';

    const nameSpan = document.createElement('span');
    nameSpan.className = 'text-white font-medium block';
    nameSpan.textContent = attachment.name;

    const levelSpan = document.createElement('span');
    levelSpan.className = 'text-gray-400 text-sm block';
    if (attachment.page === 0) {
      levelSpan.textContent = 'Document-level attachment';
    } else {
      levelSpan.textContent = `Page ${attachment.page} attachment`;
    }

    infoDiv.append(nameSpan, levelSpan);

    const actionsDiv = document.createElement('div');
    actionsDiv.className = 'flex items-center gap-2';

    const removeBtn = document.createElement('button');
    removeBtn.className = `${pageState.attachmentsToRemove.has(attachment.index) ? 'bg-gray-600' : 'bg-red-600'} hover:bg-red-700 text-white px-3 py-1 rounded text-sm`;
    removeBtn.innerHTML = '<i data-lucide="trash-2" class="w-4 h-4"></i>';
    removeBtn.title = 'Remove attachment';
    removeBtn.onclick = function () {
      if (pageState.attachmentsToRemove.has(attachment.index)) {
        pageState.attachmentsToRemove.delete(attachment.index);
        attachmentDiv.classList.remove('opacity-50', 'line-through');
        removeBtn.classList.remove('bg-gray-600');
        removeBtn.classList.add('bg-red-600');
      } else {
        pageState.attachmentsToRemove.add(attachment.index);
        attachmentDiv.classList.add('opacity-50', 'line-through');
        removeBtn.classList.add('bg-gray-600');
        removeBtn.classList.remove('bg-red-600');
      }

      const allSelected = pageState.allAttachments.every(function (att) {
        return pageState.attachmentsToRemove.has(att.index);
      });
      removeAllBtn.textContent = allSelected
        ? 'Deselect All'
        : 'Remove All Attachments';
    };

    actionsDiv.append(removeBtn);
    attachmentDiv.append(infoDiv, actionsDiv);
    attachmentsList.appendChild(attachmentDiv);
  }

  createIcons({ icons });

  if (processBtn) processBtn.classList.remove('hidden');
}

async function loadAttachments() {
  if (!pageState.file) return;

  showLoader('Loading attachments...');

  // Check if CPDF is configured
  if (!isCpdfAvailable()) {
    showWasmRequiredDialog('cpdf');
    hideLoader();
    return;
  }

  try {
    const fileBuffer = await pageState.file.arrayBuffer();

    const message = {
      command: 'get-attachments',
      fileBuffer: fileBuffer,
      fileName: pageState.file.name,
      cpdfUrl: WasmProvider.getUrl('cpdf')! + 'coherentpdf.browser.min.js',
    };

    worker.postMessage(message, [fileBuffer]);
  } catch (error) {
    console.error('Error loading attachments:', error);
    hideLoader();
    showAlert('Error', 'Failed to load attachments from PDF.');
  }
}

async function saveChanges() {
  if (!pageState.file) {
    showAlert('Error', 'No PDF file loaded.');
    return;
  }

  if (pageState.attachmentsToRemove.size === 0) {
    showAlert('No Changes', 'No attachments selected for removal.');
    return;
  }

  showLoader('Processing attachments...');

  // Check if CPDF is configured (double check)
  if (!isCpdfAvailable()) {
    showWasmRequiredDialog('cpdf');
    hideLoader();
    return;
  }

  try {
    const fileBuffer = await pageState.file.arrayBuffer();

    const message = {
      command: 'edit-attachments',
      fileBuffer: fileBuffer,
      fileName: pageState.file.name,
      attachmentsToRemove: Array.from(pageState.attachmentsToRemove),
      cpdfUrl: WasmProvider.getUrl('cpdf')! + 'coherentpdf.browser.min.js',
    };

    worker.postMessage(message, [fileBuffer]);
  } catch (error) {
    console.error('Error editing attachments:', error);
    hideLoader();
    showAlert('Error', 'Failed to edit attachments.');
  }
}

async function updateUI() {
  const fileDisplayArea = document.getElementById('file-display-area');
  const toolOptions = document.getElementById('tool-options');

  if (!fileDisplayArea) return;

  fileDisplayArea.innerHTML = '';

  if (pageState.file) {
    const fileDiv = document.createElement('div');
    fileDiv.className =
      'flex items-center justify-between bg-gray-700 p-3 rounded-lg text-sm';

    const infoContainer = document.createElement('div');
    infoContainer.className = 'flex flex-col overflow-hidden';

    const nameSpan = document.createElement('div');
    nameSpan.className = 'truncate font-medium text-gray-200 text-sm mb-1';
    nameSpan.textContent = pageState.file.name;

    const metaSpan = document.createElement('div');
    metaSpan.className = 'text-xs text-gray-400';
    metaSpan.textContent = formatBytes(pageState.file.size);

    infoContainer.append(nameSpan, metaSpan);

    const removeBtn = document.createElement('button');
    removeBtn.className = 'ml-4 text-red-400 hover:text-red-300 flex-shrink-0';
    removeBtn.innerHTML = '<i data-lucide="trash-2" class="w-4 h-4"></i>';
    removeBtn.onclick = function () {
      resetState();
    };

    fileDiv.append(infoContainer, removeBtn);
    fileDisplayArea.appendChild(fileDiv);
    createIcons({ icons });

    if (toolOptions) toolOptions.classList.remove('hidden');

    await loadAttachments();
  } else {
    if (toolOptions) toolOptions.classList.add('hidden');
  }
}

function handleFileSelect(files: FileList | null) {
  if (files && files.length > 0) {
    const file = files[0];
    if (
      file.type === 'application/pdf' ||
      file.name.toLowerCase().endsWith('.pdf')
    ) {
      pageState.file = file;
      updateUI();
    }
  }
}

document.addEventListener('DOMContentLoaded', function () {
  const fileInput = document.getElementById('file-input') as HTMLInputElement;
  const dropZone = document.getElementById('drop-zone');
  const processBtn = document.getElementById('process-btn');
  const backBtn = document.getElementById('back-to-tools');

  if (backBtn) {
    backBtn.addEventListener('click', function () {
      window.location.href = import.meta.env.BASE_URL;
    });
  }

  if (fileInput && dropZone) {
    fileInput.addEventListener('change', function (e) {
      handleFileSelect((e.target as HTMLInputElement).files);
    });

    dropZone.addEventListener('dragover', function (e) {
      e.preventDefault();
      dropZone.classList.add('bg-gray-700');
    });

    dropZone.addEventListener('dragleave', function (e) {
      e.preventDefault();
      dropZone.classList.remove('bg-gray-700');
    });

    dropZone.addEventListener('drop', function (e) {
      e.preventDefault();
      dropZone.classList.remove('bg-gray-700');
      const files = e.dataTransfer?.files;
      if (files && files.length > 0) {
        const pdfFiles = Array.from(files).filter(function (f) {
          return (
            f.type === 'application/pdf' ||
            f.name.toLowerCase().endsWith('.pdf')
          );
        });
        if (pdfFiles.length > 0) {
          const dataTransfer = new DataTransfer();
          dataTransfer.items.add(pdfFiles[0]);
          handleFileSelect(dataTransfer.files);
        }
      }
    });

    fileInput.addEventListener('click', function () {
      fileInput.value = '';
    });
  }

  if (processBtn) {
    processBtn.addEventListener('click', saveChanges);
  }
});