import FileIconFactory from './file-icon-factory.js';
import FileUtils from './file-utils.js';
import UUID from './uuid.js';
import { DecryptFile } from './DecryptFiles.js';

let isScriptExecuted = false;
if (!isScriptExecuted) {
  isScriptExecuted = true;
  document.addEventListener('DOMContentLoaded', function () {
    document.querySelectorAll('.custom-file-chooser').forEach(setupFileInput);
  });
}
let hasDroppedImage = false;

const zipTypes = [
  'application/zip',
  'multipart/x-zip',
  'application/zip-compressed',
  'application/x-zip-compressed',
];

const mimeTypes = {
  "png": "image/png",
  "jpg": "image/jpeg",
  "jpeg": "image/jpeg",
  "gif": "image/gif",
  "bmp": "image/bmp",
  "svg": "image/svg+xml",
  "pdf": "application/pdf",
};

function setupFileInput(chooser) {
  const elementId = chooser.getAttribute('data-bs-element-id');
  const filesSelected = chooser.getAttribute('data-bs-files-selected');
  const pdfPrompt = chooser.getAttribute('data-bs-pdf-prompt');
  const inputContainerId = chooser.getAttribute('data-bs-element-container-id');
  const showUploads = chooser.getAttribute('data-bs-show-uploads') === "true";
  const name = chooser.getAttribute('data-bs-unique-id')
  const noFileSelectedPrompt = chooser.getAttribute('data-bs-no-file-selected');

  let inputContainer = document.getElementById(inputContainerId);
  const input = document.getElementById(elementId);

  if (inputContainer.id === 'pdf-upload-input-container') {
    inputContainer.querySelector('#dragAndDrop').innerHTML = window.fileInput.dragAndDropPDF;
  } else if (inputContainer.id === 'image-upload-input-container') {
    inputContainer.querySelector('#dragAndDrop').innerHTML = window.fileInput.dragAndDropImage;
  } else if (inputContainer.id === 'attachments-input-container') {
    inputContainer.querySelector('#dragAndDrop').innerHTML = window.fileInput.addAttachments;
  }
  let allFiles = [];
  let overlay;
  let dragCounter = 0;

  input.addEventListener('reset', (e) => {
    allFiles = [];
    input.value = null;
  });

  inputContainer.addEventListener('click', (e) => {
    let inputBtn = document.getElementById(elementId);
    inputBtn.click();
  });

  // Handle form validation if the input is left empty
  input.addEventListener("invalid", (e) => {
    e.preventDefault();
    alert(noFileSelectedPrompt);
  });

  const dragenterListener = function () {
    dragCounter++;
    if (!overlay) {
      // Show overlay by removing display: none from pseudo elements (::before and ::after)
      inputContainer.style.setProperty('--overlay-display', "''");
      overlay = true;
    }
  };

  const dragleaveListener = function () {
    dragCounter--;
    if (dragCounter === 0) {
      hideOverlay();
    }
  };

  function hideOverlay() {
    if (!overlay) return;
    inputContainer.style.setProperty('--overlay-display', 'none');
    overlay = false;
  }

  const googleDriveFileListener = function (e) {
    const googleDriveFiles = e.detail;

    const fileInput = document.getElementById(elementId);
    if (fileInput?.hasAttribute('multiple')) {
      pushFileListTo(googleDriveFiles, allFiles);
    } else if (fileInput) {
      allFiles = [googleDriveFiles[0]];
    }

    const dataTransfer = new DataTransfer();
    allFiles.forEach((file) => dataTransfer.items.add(file));
    fileInput.files = dataTransfer.files;
    fileInput.dispatchEvent(new CustomEvent('change', { bubbles: true, detail: { source: 'drag-drop' } }));
  }

  const dropListener = function (e) {
    e.preventDefault();
    // Drag and Drop shall only affect the target file chooser
    if (e.target !== inputContainer) {
      hideOverlay();
      dragCounter = 0;
      return;
    }

    const dt = e.dataTransfer;
    const files = dt.files;

    const fileInput = document.getElementById(elementId);
    if (fileInput?.hasAttribute('multiple')) {
      pushFileListTo(files, allFiles);
    } else if (fileInput) {
      allFiles = [files[0]];
    }

    const dataTransfer = new DataTransfer();
    allFiles.forEach((file) => dataTransfer.items.add(file));

    fileInput.files = dataTransfer.files;

    hideOverlay();

    dragCounter = 0;

    fileInput.dispatchEvent(new CustomEvent('change', { bubbles: true, detail: { source: 'drag-drop' } }));
  };

  function pushFileListTo(fileList, container) {
    for (let file of fileList) {
      container.push(file);
    }
  }

  ['dragenter', 'dragover', 'dragleave', 'drop'].forEach((eventName) => {
    document.body.addEventListener(eventName, preventDefaults, false);
  });

  function preventDefaults(e) {
    e.preventDefault();
    e.stopPropagation();
  }

  document.body.addEventListener('dragenter', dragenterListener);
  document.body.addEventListener('dragleave', dragleaveListener);
  document.body.addEventListener('drop', dropListener);
  document.body.addEventListener(name + 'GoogleDriveDrivePicked', googleDriveFileListener);

  $('#' + elementId).on('change', async function (e) {
    let element = e.target;
    const isDragAndDrop = e.detail?.source == 'drag-drop';

    if (element instanceof HTMLInputElement && element.hasAttribute('multiple')) {
      allFiles = isDragAndDrop ? allFiles : [...allFiles, ...element.files];
    } else {
      allFiles = Array.from(isDragAndDrop ? allFiles : [element.files[0]]);
    }

	const originalText = inputContainer.querySelector('#fileInputText').innerHTML;

	inputContainer.querySelector('#fileInputText').innerHTML = window.fileInput.loading;

    async function checkZipFile() {
      const hasZipFiles = allFiles.some(file => ((typeof(file.type) != undefined) && zipTypes.includes(file.type)));

      // Only change to extractPDF message if we actually have zip files
      if (hasZipFiles) {
        inputContainer.querySelector('#fileInputText').innerHTML = window.fileInput.extractPDF;
      }

      const promises = allFiles.map(async (file, index) => {
        try {
          if (zipTypes.includes(file.type)) {
            await extractZipFiles(file, element.accept);
            allFiles.splice(index, 1);
          }
        } catch (error) {
          console.error(`Error extracting ZIP file (${file.name}):`, error);
          allFiles.splice(index, 1);
        }
      });

      await Promise.all(promises);
    }

    const decryptFile = new DecryptFile();

    await checkZipFile();

    const uploadLimit = window.stirlingPDF?.uploadLimit ?? 0;
    if (uploadLimit > 0) {
      const oversizedFiles = allFiles.filter(f => f.size > uploadLimit);
      if (oversizedFiles.length > 0) {
        const names = oversizedFiles.map(f => `"${f.name}"`).join(', ');
        if (names.length === 1) {
          alert(`${names} ${window.stirlingPDF.uploadLimitExceededSingular} ${window.stirlingPDF.uploadLimitReadable}.`);
        } else {
          alert(`${names} ${window.stirlingPDF.uploadLimitExceededPlural} ${window.stirlingPDF.uploadLimitReadable}.`);
        }
        allFiles = allFiles.filter(f => f.size <= uploadLimit);
        const dataTransfer = new DataTransfer();
        allFiles.forEach(f => dataTransfer.items.add(f));
        input.files = dataTransfer.files;

        if (allFiles.length === 0) {
          inputContainer.querySelector('#fileInputText').innerHTML = originalText;
          return;
        }
      }
    }

    allFiles = await Promise.all(
      allFiles.map(async (file) => {
        let decryptedFile = file;

        try {
          const { isEncrypted, requiresPassword } = await decryptFile.checkFileEncrypted(file);
          if (file.type === 'application/pdf' && isEncrypted &&
              !window.location.pathname.includes('remove-password')) {
            decryptedFile = await decryptFile.decryptFile(file, requiresPassword);
            if (!decryptedFile) throw new Error('File decryption failed.');
          }
          decryptedFile.uniqueId = UUID.uuidv4();
          return decryptedFile;

        } catch (error) {
          console.error(`Error decrypting file: ${file.name}`, error);

          // Check if this is a PDF corruption error
          if (error.message && error.message.includes('PDF file is corrupted')) {
            // The error banner is already shown by DecryptFiles.js, just continue with the file
            console.warn(`Continuing with corrupted PDF file: ${file.name}`);
          }

          if (!file.uniqueId) file.uniqueId = UUID.uuidv4();
          return file;
        }
      })
    );

    inputContainer.querySelector('#fileInputText').innerHTML = originalText;
    if (!isDragAndDrop) {
      let dataTransfer = toDataTransfer(allFiles);
      element.files = dataTransfer.files;
    }

    handleFileInputChange(this);
    this.dispatchEvent(new CustomEvent('file-input-change', { bubbles: true, detail: { elementId, allFiles } }));
  });

  function toDataTransfer(files) {
    let dataTransfer = new DataTransfer();
    files.forEach((file) => dataTransfer.items.add(file));
    return dataTransfer;
  }

  async function extractZipFiles(zipFile, acceptedFileType) {
    const jszip = new JSZip();
    var counter = 0;

    // do an overall count, then proceed to make the pdf files
    await jszip.loadAsync(zipFile)
      .then(function (zip) {

          zip.forEach(function (relativePath, zipEntry) {
            counter+=1;
          })
        }
      )

    if (counter >= 1000) {
      throw Error("Maximum file reached");
    }

    return jszip.loadAsync(zipFile)
      .then(function (zip) {
        var extractionPromises = [];

       zip.forEach(function (relativePath, zipEntry) {
		    const promise = zipEntry.async('blob').then(function (content) {
		      // Assuming that folders have size zero
		      if (content.size > 0) {
		        const extension = zipEntry.name.split('.').pop().toLowerCase();
		        const mimeType = mimeTypes[extension] || 'application/octet-stream';

		        // Check if we're accepting ONLY ZIP files (in which case extract everything)
		        // or if the file type matches the accepted type
		        if (zipTypes.includes(acceptedFileType) ||
		            acceptedFileType === '*/*' ||
		            (mimeType && (mimeType.startsWith(acceptedFileType.split('/')[0]) || acceptedFileType === mimeType))) {
		          var file = new File([content], zipEntry.name, { type: mimeType });
		          file.uniqueId = UUID.uuidv4();
		          allFiles.push(file);
		        } else {
		          console.log(`File ${zipEntry.name} skipped. MIME type (${mimeType}) does not match accepted type (${acceptedFileType})`);
		        }
		      }
		    });

          extractionPromises.push(promise);
        });

        return Promise.all(extractionPromises);
      })
      .catch(function (err) {
        console.error("Error extracting ZIP file:", err);
        throw err;
      });
  }

  function handleFileInputChange(inputElement) {

    const files = allFiles;

    showOrHideSelectedFilesContainer(files);

    const filesInfo = files.map((f) => {

      const url = URL.createObjectURL(f);

      return {
        name: f.name,
        size: f.size,
        uniqueId: f.uniqueId,
        type: f.type,
        url: url,
      };
    });

    const selectedFilesContainer = $(inputContainer).siblings('.selected-files');
    selectedFilesContainer.empty();
    filesInfo.forEach((info) => {
      let fileContainerClasses = 'small-file-container d-flex flex-column justify-content-center align-items-center';

      let fileContainer = document.createElement('div');
      $(fileContainer).addClass(fileContainerClasses);
      $(fileContainer).attr('id', info.uniqueId);

      let fileIconContainer = document.createElement('div');
      const isDragAndDropEnabled =
        window.location.pathname.includes('add-image') || window.location.pathname.includes('sign');

      // add image thumbnail to it
      if (info.type.startsWith('image/')) {
        let imgPreview = document.createElement('img');
        imgPreview.src = info.url;
        imgPreview.alt = 'Preview';
        imgPreview.style.width = '50px';
        imgPreview.style.height = '50px';
        imgPreview.style.objectFit = 'cover';
        $(fileIconContainer).append(imgPreview);

        if (isDragAndDropEnabled) {
          let dragIcon = document.createElement('div');
          dragIcon.classList.add('drag-icon');
          dragIcon.innerHTML =
            '<svg xmlns="http://www.w3.org/2000/svg" height="24px" viewBox="0 -960 960 960" width="24px" fill="#e8eaed"><path d="M360-160q-33 0-56.5-23.5T280-240q0-33 23.5-56.5T360-320q33 0 56.5 23.5T440-240q0 33-23.5 56.5T360-160Zm240 0q-33 0-56.5-23.5T520-240q0-33 23.5-56.5T600-320q33 0 56.5 23.5T680-240q0 33-23.5 56.5T600-160ZM360-400q-33 0-56.5-23.5T280-480q0-33 23.5-56.5T360-560q33 0 56.5 23.5T440-480q0 33-23.5 56.5T360-400Zm240 0q-33 0-56.5-23.5T520-480q0-33 23.5-56.5T600-560q33 0 56.5 23.5T680-480q0 33-23.5 56.5T600-400ZM360-640q-33 0-56.5-23.5T280-720q0-33 23.5-56.5T360-800q33 0 56.5 23.5T440-720q0 33-23.5 56.5T360-640Zm240 0q-33 0-56.5-23.5T520-720q0-33 23.5-56.5T600-800q33 0 56.5 23.5T680-720q0 33-23.5 56.5T600-640Z"/></svg>';
          fileContainer.appendChild(dragIcon);

          $(fileContainer).attr('draggable', 'true');
          $(fileContainer).on('dragstart', (e) => {
            e.originalEvent.dataTransfer.setData('fileUrl', info.url);
            e.originalEvent.dataTransfer.setData('uniqueId', info.uniqueId);
            e.originalEvent.dataTransfer.setDragImage(imgPreview, imgPreview.width / 2, imgPreview.height / 2);
          });
          enableImagePreviewOnClick(fileIconContainer);
        } else {
          $(fileContainer).removeAttr('draggable');
        }
      } else {
        fileIconContainer = createFileIconContainer(info);
      }

      let fileInfoContainer = createFileInfoContainer(info);

      if (!isDragAndDropEnabled) {
        let removeBtn = document.createElement('div');
        removeBtn.classList.add('remove-selected-file');

        let removeBtnIconHTML = `<svg xmlns="http://www.w3.org/2000/svg" height="20px" viewBox="0 -960 960 960" width="20px" fill="#C02223"><path d="m339-288 141-141 141 141 51-51-141-141 141-141-51-51-141 141-141-141-51 51 141 141-141 141 51 51ZM480-96q-79 0-149-30t-122.5-82.5Q156-261 126-331T96-480q0-80 30-149.5t82.5-122Q261-804 331-834t149-30q80 0 149.5 30t122 82.5Q804-699 834-629.5T864-480q0 79-30 149t-82.5 122.5Q699-156 629.5-126T480-96Z"/></svg>`;
        $(removeBtn).append(removeBtnIconHTML);
        $(removeBtn).attr('data-file-id', info.uniqueId).click(removeFileListener);
        $(fileContainer).append(removeBtn);
      }
      $(fileContainer).append(fileIconContainer, fileInfoContainer);

      selectedFilesContainer.append(fileContainer);
    });
    const pageContainers = $('#box-drag-container');
    pageContainers.off('dragover').on('dragover', (e) => {
      e.preventDefault();
    });

    pageContainers.off('drop').on('drop', (e) => {
      e.preventDefault();
      const fileUrl = e.originalEvent.dataTransfer.getData('fileUrl');

      if (fileUrl) {
        const existingImages = $(e.target).find(`img[src="${fileUrl}"]`);
        if (existingImages.length === 0) {
          DraggableUtils.createDraggableCanvasFromUrl(fileUrl);
        }
      }
      const overlayElement = chooser.querySelector('.drag-drop-overlay');
      if (overlayElement) {
        overlayElement.style.display = 'none';
      }
      hasDroppedImage = true;
    });

    showOrHideSelectedFilesContainer(files);
  }

  function showOrHideSelectedFilesContainer(files) {
    if (showUploads && files && files.length > 0) {
      chooser.style.setProperty('--selected-files-display', 'flex');
    } else {
      chooser.style.setProperty('--selected-files-display', 'none');
    }
    const isDragAndDropEnabled =
      (window.location.pathname.includes('add-image') || window.location.pathname.includes('sign')) &&
      files.some((file) => file.type.startsWith('image/'));

    if (!isDragAndDropEnabled) return;

    const selectedFilesContainer = chooser.querySelector('.selected-files');

    let overlayElement = chooser.querySelector('.drag-drop-overlay');
    if (!overlayElement) {
      selectedFilesContainer.style.position = 'relative';
      overlayElement = document.createElement('div');
      overlayElement.classList.add('draggable-image-overlay');

      overlayElement.innerHTML = 'Drag images to add them to the page';
      selectedFilesContainer.appendChild(overlayElement);
    }
    if (hasDroppedImage) overlayElement.style.display = files && files.length > 0 ? 'flex' : 'none';

    selectedFilesContainer.addEventListener('mouseenter', () => {
      overlayElement.style.display = 'none';
    });

    selectedFilesContainer.addEventListener('mouseleave', () => {
      if (!hasDroppedImage) overlayElement.style.display = files && files.length > 0 ? 'flex' : 'none';
    });
  }

  function removeFileListener(e) {
    const fileId = e.target.getAttribute('data-file-id');

    let inputElement = document.getElementById(elementId);
    removeFileById(fileId, inputElement);

    showOrHideSelectedFilesContainer(allFiles);

    inputElement.dispatchEvent(new CustomEvent('file-input-change', { bubbles: true }));
  }

  function removeFileById(fileId, inputElement) {
    let fileContainer = document.getElementById(fileId);
    fileContainer.remove();

    allFiles = allFiles.filter((v) => v.uniqueId != fileId);
    let dataTransfer = toDataTransfer(allFiles);

    if (inputElement) inputElement.files = dataTransfer.files;
  }

  function createFileIconContainer(info) {
    let fileIconContainer = document.createElement('div');
    fileIconContainer.classList.add('file-icon');

    // Add icon based on the extension
    let fileExtension = FileUtils.extractFileExtension(info.name);
    let fileIcon = FileIconFactory.createFileIcon(fileExtension);

    $(fileIconContainer).append(fileIcon);
    return fileIconContainer;
  }

  function createFileInfoContainer(info) {
    let fileInfoContainer = document.createElement('div');
    let fileInfoContainerClasses = 'file-info d-flex flex-column align-items-center justify-content-center';

    $(fileInfoContainer).addClass(fileInfoContainerClasses);

    $(fileInfoContainer).append(`<div title="${info.name}">${info.name}</div>`);
    let fileSizeWithUnits = FileUtils.transformFileSize(info.size);
    $(fileInfoContainer).append(`<div title="${info.size}">${fileSizeWithUnits}</div>`);
    return fileInfoContainer;
  }

  //Listen for event of file being removed and the filter it out of the allFiles array
  document.addEventListener('fileRemoved', function (e) {
    const fileId = e.detail;
    let inputElement = document.getElementById(elementId);
    removeFileById(fileId, inputElement);
    showOrHideSelectedFilesContainer(allFiles);
  });
  function enableImagePreviewOnClick(container) {
    const imagePreviewModal = document.getElementById('imagePreviewModal') || createImagePreviewModal();

    container.querySelectorAll('img').forEach((img) => {
      if (!img.hasPreviewListener) {
        img.addEventListener('mouseup', function () {
          const imgElement = imagePreviewModal.querySelector('img');
          imgElement.src = this.src;
          imagePreviewModal.style.display = 'flex';
        });
        img.hasPreviewListener = true;
      }
    });

    function createImagePreviewModal() {
      const modal = document.createElement('div');
      modal.id = 'imagePreviewModal';
      modal.style.position = 'fixed';
      modal.style.top = '0';
      modal.style.left = '0';
      modal.style.width = '100vw';
      modal.style.height = '100vh';
      modal.style.backgroundColor = 'rgba(0, 0, 0, 0.7)';
      modal.style.display = 'none';
      modal.style.justifyContent = 'center';
      modal.style.alignItems = 'center';
      modal.style.zIndex = '2000';

      const imgElement = document.createElement('img');
      imgElement.style.maxWidth = '90%';
      imgElement.style.maxHeight = '90%';

      modal.appendChild(imgElement);
      document.body.appendChild(modal);

      modal.addEventListener('click', () => {
        modal.style.display = 'none';
      });

      document.addEventListener('keydown', (e) => {
        if (e.key === 'Escape' && modal.style.display === 'flex') {
          modal.style.display = 'none';
        }
      });

      return modal;
    }
  }
}
