Static Methods and Utilities

/**
 * Find existing Dropzone instance for an element
 * @param element - CSS selector string or HTMLElement
 * @returns Dropzone instance attached to the element
 * @throws Error if no Dropzone found for element
 */
static forElement(element: string | HTMLElement): Dropzone;

/**
 * Automatically discover and initialize all .dropzone elements
 */
static discover(): void;

/**
 * Global array of all Dropzone instances
 */
static instances: Dropzone[];

/**
 * Current version of Dropzone library
 */
static version: string;

// Create dropzones
const dropzone1 = new Dropzone("#upload1", { url: "/upload" });
const dropzone2 = new Dropzone("#upload2", { url: "/upload" });

// Access existing dropzone instance
const existingDropzone = Dropzone.forElement("#upload1");
console.log("Found dropzone:", existingDropzone === dropzone1); // true

// Access by DOM element
const element = document.getElementById("upload2");
const dropzoneByElement = Dropzone.forElement(element);

// List all instances
console.log("Total dropzones:", Dropzone.instances.length);
Dropzone.instances.forEach((dz, index) => {
  console.log(`Dropzone ${index}:`, dz.element.id);
});

// Get library version
console.log("Dropzone version:", Dropzone.version); // "4.3.0"

// Auto-discover dropzones
Dropzone.discover(); // Initializes all .dropzone elements

// Error handling
try {
  const nonExistent = Dropzone.forElement("#not-found");
} catch (error) {
  console.error("Dropzone not found:", error.message);
}

/**
 * Whether to automatically discover and initialize .dropzone elements
 */
static autoDiscover: boolean;

/**
 * Global options object for configuring dropzones by element ID
 * Key: camelCase version of element ID
 * Value: DropzoneOptions object or false to disable
 */
static options: { [elementId: string]: DropzoneOptions | false };

/**
 * Get options for a specific element
 * @param element - HTMLElement to get options for
 * @returns Options object or undefined
 */
static optionsForElement(element: HTMLElement): DropzoneOptions | false | undefined;

<!-- HTML elements -->
<form id="my-awesome-dropzone" action="/upload" class="dropzone"></form>
<div id="simple-upload" class="dropzone"></div>
<div id="disabled-dropzone" class="dropzone"></div>

// Configure dropzones before auto-discovery
Dropzone.options.myAwesomeDropzone = {
  maxFilesize: 2,
  acceptedFiles: "image/*",
  dictDefaultMessage: "Drop images here"
};

Dropzone.options.simpleUpload = {
  url: "/api/files",
  maxFiles: 5,
  addRemoveLinks: true
};

// Disable auto-discovery for specific element
Dropzone.options.disabledDropzone = false;

// Check configuration
const element = document.getElementById("my-awesome-dropzone");
const config = Dropzone.optionsForElement(element);
console.log("Configuration:", config);

// Disable auto-discovery globally
Dropzone.autoDiscover = false;

// Manual discovery after configuration
Dropzone.discover();

// Re-enable auto-discovery
Dropzone.autoDiscover = true;

/**
 * Create DOM element from HTML string
 * @param string - HTML string to convert to element
 * @returns HTMLElement created from string
 */
static createElement(string: string): HTMLElement;

/**
 * Test if element is inside (or is) the container
 * @param element - Element to test
 * @param container - Container element
 * @returns true if element is inside container
 */
static elementInside(element: HTMLElement, container: HTMLElement): boolean;

/**
 * Get single element from selector or element
 * @param el - CSS selector string or HTMLElement
 * @param name - Name for error messages
 * @returns HTMLElement
 * @throws Error if element not found or invalid
 */
static getElement(el: string | HTMLElement, name: string): HTMLElement;

/**
 * Get multiple elements from various input types
 * @param els - CSS selector, HTMLElement, or array of elements
 * @param name - Name for error messages
 * @returns Array of HTMLElements
 * @throws Error if no valid elements found
 */
static getElements(els: string | HTMLElement | HTMLElement[], name: string): HTMLElement[];

// Create elements from HTML strings
const previewElement = Dropzone.createElement(`
  <div class="file-preview">
    <img class="thumbnail" />
    <span class="filename"></span>
  </div>
`);
document.body.appendChild(previewElement);

// Test element containment
const dropzoneEl = document.getElementById("my-dropzone");
const fileInput = dropzoneEl.querySelector("input[type=file]");
const isInside = Dropzone.elementInside(fileInput, dropzoneEl);
console.log("Input is inside dropzone:", isInside); // true

// Get single element
const uploadArea = Dropzone.getElement("#upload-area", "upload area");
const formElement = Dropzone.getElement(document.forms[0], "form");

// Get multiple elements
const clickableElements = Dropzone.getElements([
  "#upload-button",
  "#drop-area",
  document.querySelector(".upload-zone")
], "clickable elements");

console.log("Found", clickableElements.length, "clickable elements");

// Error handling
try {
  const invalidElement = Dropzone.getElement("#nonexistent", "test element");
} catch (error) {
  console.error("Element not found:", error.message);
}

try {
  const noElements = Dropzone.getElements("", "empty selector");
} catch (error) {
  console.error("No elements found:", error.message);
}

/**
 * Validate file against accepted file types
 * @param file - File object to validate
 * @param acceptedFiles - Comma-separated string of accepted MIME types/extensions
 * @returns true if file is valid
 */
static isValidFile(file: File, acceptedFiles: string): boolean;

/**
 * Check if current browser supports drag and drop file uploads
 * @returns true if browser is supported
 */
static isBrowserSupported(): boolean;

/**
 * Array of regex patterns for blacklisted browsers
 */
static blacklistedBrowsers: RegExp[];

// File validation
const file = new File(["content"], "document.pdf", { type: "application/pdf" });

// Test against various accepted types
console.log("PDF accepted (application/pdf):", 
  Dropzone.isValidFile(file, "application/pdf")); // true

console.log("PDF accepted (pdf extension):", 
  Dropzone.isValidFile(file, ".pdf")); // true

console.log("PDF accepted (documents):", 
  Dropzone.isValidFile(file, "application/*")); // true

console.log("PDF accepted (images only):", 
  Dropzone.isValidFile(file, "image/*")); // false

// Multiple accepted types
const acceptedTypes = "image/*,application/pdf,.doc,.docx";
console.log("PDF in mixed types:", 
  Dropzone.isValidFile(file, acceptedTypes)); // true

// Image file validation
const imageFile = new File([""], "photo.jpg", { type: "image/jpeg" });
console.log("JPEG accepted:", 
  Dropzone.isValidFile(imageFile, "image/*")); // true

// Browser support detection
if (Dropzone.isBrowserSupported()) {
  console.log("Browser supports drag and drop uploads");
  new Dropzone("#my-dropzone", { url: "/upload" });
} else {
  console.log("Browser not supported, showing fallback");
  document.getElementById("fallback-form").style.display = "block";
}

// Check blacklisted browsers
console.log("Blacklisted browsers:", Dropzone.blacklistedBrowsers);
// Example: [/opera.*Macintosh.*version\/12/i]

// Custom browser detection
function isModernBrowser() {
  const supported = Dropzone.isBrowserSupported();
  const isBlacklisted = Dropzone.blacklistedBrowsers.some(regex => 
    regex.test(navigator.userAgent)
  );
  return supported && !isBlacklisted;
}

/**
 * Show confirmation dialog to user
 * @param question - Question to ask user
 * @param accepted - Callback if user accepts
 * @param rejected - Optional callback if user rejects
 */
static confirm(question: string, accepted: () => void, rejected?: () => void): void;

// Basic confirmation
Dropzone.confirm(
  "Are you sure you want to remove this file?",
  function() {
    console.log("User confirmed removal");
    // Proceed with removal
  },
  function() {
    console.log("User canceled removal");
    // Handle cancellation
  }
);

// Custom confirmation with dropzone integration
const dropzone = new Dropzone("#my-dropzone", {
  url: "/upload",
  addRemoveLinks: true,
  
  init: function() {
    this.on("removedfile", function(file) {
      // This uses Dropzone.confirm internally for dictRemoveFileConfirmation
      console.log("File removed:", file.name);
    });
  },
  
  // Enable confirmation for file removal
  dictRemoveFileConfirmation: "Are you sure you want to delete this file?"
});

// Override default confirm function
const originalConfirm = Dropzone.confirm;
Dropzone.confirm = function(question, accepted, rejected) {
  // Use custom modal instead of window.confirm
  showCustomModal({
    title: "Confirm Action",
    message: question,
    onConfirm: accepted,
    onCancel: rejected
  });
};

function showCustomModal(options) {
  const modal = document.createElement("div");
  modal.className = "custom-modal";
  modal.innerHTML = `
    <div class="modal-content">
      <h3>${options.title}</h3>
      <p>${options.message}</p>
      <button class="confirm-btn">Confirm</button>
      <button class="cancel-btn">Cancel</button>
    </div>
  `;
  
  modal.querySelector(".confirm-btn").onclick = function() {
    modal.remove();
    options.onConfirm();
  };
  
  modal.querySelector(".cancel-btn").onclick = function() {
    modal.remove();
    if (options.onCancel) options.onCancel();
  };
  
  document.body.appendChild(modal);
}

// Restore original confirm function
// Dropzone.confirm = originalConfirm;

// Internal helper functions (available but not part of public API)

/**
 * Remove item from array
 * @param list - Array to filter
 * @param rejectedItem - Item to remove
 * @returns New array without rejected item
 */
function without<T>(list: T[], rejectedItem: T): T[];

/**
 * Convert kebab-case or snake_case to camelCase
 * @param str - String to convert
 * @returns Camelized string
 */
function camelize(str: string): string;

// These are internal functions, but can be useful for custom implementations

// Array filtering (similar to lodash without)
const files = [file1, file2, file3];
const filteredFiles = without(files, file2);
console.log("Filtered files:", filteredFiles); // [file1, file3]

// String camelization for element IDs
const elementId = "my-awesome-dropzone";
const camelized = camelize(elementId);
console.log("Camelized:", camelized); // "myAwesomeDropzone"

// This is how Dropzone internally converts element IDs to option keys
const element = document.getElementById("upload-form-area");
const optionKey = camelize(element.getAttribute("id"));
console.log("Option key:", optionKey); // "uploadFormArea"

// Access options using camelized key
const options = Dropzone.options[optionKey];

// Centralized dropzone configuration
const DropzoneManager = {
  defaultOptions: {
    maxFilesize: 5,
    acceptedFiles: "image/*,application/pdf",
    addRemoveLinks: true,
    dictDefaultMessage: "Drop files here to upload"
  },
  
  instances: [],
  
  create: function(selector, customOptions = {}) {
    const options = Object.assign({}, this.defaultOptions, customOptions);
    const dropzone = new Dropzone(selector, options);
    this.instances.push(dropzone);
    return dropzone;
  },
  
  destroyAll: function() {
    this.instances.forEach(dz => dz.destroy());
    this.instances = [];
  },
  
  getByElement: function(element) {
    return this.instances.find(dz => dz.element === element);
  }
};

// Use centralized manager
const uploadDropzone = DropzoneManager.create("#upload-area", {
  url: "/api/upload",
  maxFiles: 10
});

const avatarDropzone = DropzoneManager.create("#avatar-upload", {
  url: "/api/avatar",
  maxFiles: 1,
  acceptedFiles: "image/*"
});

// Global event handling
function setupGlobalDropzoneEvents() {
  Dropzone.instances.forEach(dropzone => {
    dropzone.on("success", function(file, response) {
      console.log(`Upload successful in ${this.element.id}:`, file.name);
    });
    
    dropzone.on("error", function(file, message) {
      console.error(`Upload failed in ${this.element.id}:`, message);
    });
  });
}

// Setup global events after auto-discovery
document.addEventListener("DOMContentLoaded", function() {
  // Wait for auto-discovery to complete
  setTimeout(setupGlobalDropzoneEvents, 100);
});