/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef nsIFormControl_h___
#define nsIFormControl_h___

#include "nsISupports.h"
class nsIDOMHTMLFormElement;
class nsPresState;
class nsString;
class nsIFormProcessor;
class nsFormSubmission;

namespace mozilla {
namespace dom {
class Element;
} // namespace dom
} // namespace mozilla

enum FormControlsTypes {
  NS_FORM_FIELDSET = 1,
  NS_FORM_LABEL,
  NS_FORM_OUTPUT,
  NS_FORM_SELECT,
  NS_FORM_TEXTAREA,
  NS_FORM_OBJECT,
  eFormControlsWithoutSubTypesMax,
  // After this, all types will have sub-types which introduce new enum lists.
  // eFormControlsWithoutSubTypesMax let us know if the previous types values
  // are not overlapping with sub-types/masks.

  // Elements with different types, the value is used as a mask.
  // Adding '_ELEMENT' because NS_FORM_INPUT is used for 'oninput' event.
  // When changing the order, adding or removing elements, be sure to update
  // the PR_STATIC_ASSERT checks accordingly.
  NS_FORM_BUTTON_ELEMENT = 0x40, // 0b01000000
  NS_FORM_INPUT_ELEMENT  = 0x80  // 0b10000000
};

enum ButtonElementTypes {
  NS_FORM_BUTTON_BUTTON = NS_FORM_BUTTON_ELEMENT + 1,
  NS_FORM_BUTTON_RESET,
  NS_FORM_BUTTON_SUBMIT,
  eButtonElementTypesMax
};

enum InputElementTypes {
  NS_FORM_INPUT_BUTTON = NS_FORM_INPUT_ELEMENT + 1,
  NS_FORM_INPUT_CHECKBOX,
  NS_FORM_INPUT_EMAIL,
  NS_FORM_INPUT_FILE,
  NS_FORM_INPUT_HIDDEN,
  NS_FORM_INPUT_RESET,
  NS_FORM_INPUT_IMAGE,
  NS_FORM_INPUT_NUMBER,
  NS_FORM_INPUT_PASSWORD,
  NS_FORM_INPUT_RADIO,
  NS_FORM_INPUT_SEARCH,
  NS_FORM_INPUT_SUBMIT,
  NS_FORM_INPUT_TEL,
  NS_FORM_INPUT_TEXT,
  NS_FORM_INPUT_URL,
  eInputElementTypesMax
};

PR_STATIC_ASSERT((uint32_t)eFormControlsWithoutSubTypesMax < (uint32_t)NS_FORM_BUTTON_ELEMENT);
PR_STATIC_ASSERT((uint32_t)eButtonElementTypesMax < (uint32_t)NS_FORM_INPUT_ELEMENT);
PR_STATIC_ASSERT((uint32_t)eInputElementTypesMax  < 1<<8);

#define NS_IFORMCONTROL_IID   \
{ 0xbc53dcf5, 0xbd4f, 0x4991, \
 { 0xa1, 0x87, 0xc4, 0x57, 0x98, 0x54, 0xda, 0x6e } }

/**
 * Interface which all form controls (e.g. buttons, checkboxes, text,
 * radio buttons, select, etc) implement in addition to their dom specific
 * interface.
 */
class nsIFormControl : public nsISupports
{
public:

  NS_DECLARE_STATIC_IID_ACCESSOR(NS_IFORMCONTROL_IID)

  /**
   * Get the form for this form control.
   * @return the form
   */
  virtual mozilla::dom::Element *GetFormElement() = 0;

  /**
   * Set the form for this form control.
   * @param aForm the form.  This must not be null.
   *
   * @note that when setting the form the control is not added to the
   * form.  It adds itself when it gets bound to the tree thereafter,
   * so that it can be properly sorted with the other controls in the
   * form.
   */
  virtual void SetForm(nsIDOMHTMLFormElement* aForm) = 0;

  /**
   * Tell the control to forget about its form.
   *
   * @param aRemoveFromForm set false if you do not want this element removed
   *        from the form.  (Used by nsFormControlList::Clear())
   */
  virtual void ClearForm(bool aRemoveFromForm) = 0;

  /**
   * Get the type of this control as an int (see NS_FORM_* above)
   * @return the type of this control
   */
  NS_IMETHOD_(uint32_t) GetType() const = 0 ;

  /**
   * Reset this form control (as it should be when the user clicks the Reset
   * button)
   */
  NS_IMETHOD Reset() = 0;

  /**
   * Tells the form control to submit its names and values to the form
   * submission object
   * @param aFormSubmission the form submission to notify of names/values/files
   *                       to submit
   */
  NS_IMETHOD SubmitNamesValues(nsFormSubmission* aFormSubmission) = 0;

  /**
   * Save to presentation state.  The form control will determine whether it
   * has anything to save and if so, create an entry in the layout history for
   * its pres context.
   */
  NS_IMETHOD SaveState() = 0;

  /**
   * Restore from presentation state.  You pass in the presentation state for
   * this form control (generated with GenerateStateKey() + "-C") and the form
   * control will grab its state from there.
   *
   * @param aState the pres state to use to restore the control
   * @return true if the form control was a checkbox and its
   *         checked state was restored, false otherwise.
   */
  virtual bool RestoreState(nsPresState* aState) = 0;

  virtual bool AllowDrop() = 0;

  /**
   * Returns whether this is a control which submits the form when activated by
   * the user.
   * @return whether this is a submit control.
   */
  inline bool IsSubmitControl() const;

  /**
   * Returns whether this is a text control.
   * @param  aExcludePassword  to have NS_FORM_INPUT_PASSWORD returning false.
   * @return whether this is a text control.
   */
  inline bool IsTextControl(bool aExcludePassword) const ;

  /**
   * Returns whether this is a single line text control.
   * @param  aExcludePassword  to have NS_FORM_INPUT_PASSWORD returning false.
   * @return whether this is a single line text control.
   */
  inline bool IsSingleLineTextControl(bool aExcludePassword) const;

  /**
   * Returns whether this is a submittable form control.
   * @return whether this is a submittable form control.
   */
  inline bool IsSubmittableControl() const;

  /**
   * Returns whether this form control can have draggable children.
   * @return whether this form control can have draggable children.
   */
  inline bool AllowDraggableChildren() const;

protected:

  /**
   * Returns whether mType corresponds to a single line text control type.
   * @param aExcludePassword to have NS_FORM_INPUT_PASSWORD ignored.
   * @param aType the type to be tested.
   * @return whether mType corresponds to a single line text control type.
   */
  inline static bool IsSingleLineTextControl(bool aExcludePassword, uint32_t aType);

  /**
   * Returns whether this is a auto-focusable form control.
   * @return whether this is a auto-focusable form control.
   */
  inline bool IsAutofocusable() const;
};

bool
nsIFormControl::IsSubmitControl() const
{
  uint32_t type = GetType();
  return type == NS_FORM_INPUT_SUBMIT ||
         type == NS_FORM_INPUT_IMAGE ||
         type == NS_FORM_BUTTON_SUBMIT;
}

bool
nsIFormControl::IsTextControl(bool aExcludePassword) const
{
  uint32_t type = GetType();
  return type == NS_FORM_TEXTAREA ||
         IsSingleLineTextControl(aExcludePassword, type);
}

bool
nsIFormControl::IsSingleLineTextControl(bool aExcludePassword) const
{
  return IsSingleLineTextControl(aExcludePassword, GetType());
}

/*static*/
bool
nsIFormControl::IsSingleLineTextControl(bool aExcludePassword, uint32_t aType)
{
  return aType == NS_FORM_INPUT_TEXT ||
         aType == NS_FORM_INPUT_EMAIL ||
         aType == NS_FORM_INPUT_SEARCH ||
         aType == NS_FORM_INPUT_TEL ||
         aType == NS_FORM_INPUT_URL ||
         // TODO: this is temporary until bug 635240 is fixed.
         aType == NS_FORM_INPUT_NUMBER ||
         (!aExcludePassword && aType == NS_FORM_INPUT_PASSWORD);
}

bool
nsIFormControl::IsSubmittableControl() const
{
  // TODO: keygen should be in that list, see bug 101019.
  uint32_t type = GetType();
  return type == NS_FORM_OBJECT ||
         type == NS_FORM_TEXTAREA ||
         type == NS_FORM_SELECT ||
         // type == NS_FORM_KEYGEN ||
         type & NS_FORM_BUTTON_ELEMENT ||
         type & NS_FORM_INPUT_ELEMENT;
}

bool
nsIFormControl::AllowDraggableChildren() const
{
  uint32_t type = GetType();
  return type == NS_FORM_OBJECT ||
         type == NS_FORM_LABEL ||
         type == NS_FORM_FIELDSET ||
         type == NS_FORM_OUTPUT;
}

bool
nsIFormControl::IsAutofocusable() const
{
  uint32_t type = GetType();
  return type & NS_FORM_INPUT_ELEMENT ||
         type & NS_FORM_BUTTON_ELEMENT ||
         type == NS_FORM_TEXTAREA ||
         type == NS_FORM_SELECT;
}

NS_DEFINE_STATIC_IID_ACCESSOR(nsIFormControl, NS_IFORMCONTROL_IID)

#endif /* nsIFormControl_h___ */
