/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */

/* vim: set ts=8 sts=2 et sw=2 tw=80: */

/* 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/. */

//#define SHOW_BOUNDING_BOX 1

#ifndef nsIMathMLFrame_h___

#define nsIMathMLFrame_h___

#include "nsQueryFrame.h"

#include "nsMathMLOperators.h"

struct nsPresentationData;

struct nsEmbellishData;

class gfxContext;

class nsIFrame;

namespace mozilla {

class ReflowOutput;

}  // namespace mozilla

// For MathML, this 'type' will be used to determine the spacing between frames

// Subclasses can return a 'type' that will give them a particular spacing

enum eMathMLFrameType {

  eMathMLFrameType_UNKNOWN = -1,

  eMathMLFrameType_Ordinary,

  eMathMLFrameType_OperatorOrdinary,

  eMathMLFrameType_OperatorInvisible,

  eMathMLFrameType_OperatorUserDefined,

  eMathMLFrameType_Inner,

  eMathMLFrameType_ItalicIdentifier,

  eMathMLFrameType_UprightIdentifier,

  eMathMLFrameType_COUNT

};

// Abstract base class that provides additional methods for MathML frames

class nsIMathMLFrame {

 public:

  NS_DECL_QUERYFRAME_TARGET(nsIMathMLFrame)

  // helper to check whether the frame is "space-like", as defined by the spec.

  virtual bool IsSpaceLike() = 0;

  /* SUPPORT FOR PRECISE POSITIONING */

  /*====================================================================*/

  /* Metrics that _exactly_ enclose the text of the frame.

   * The frame *must* have *already* being reflowed, before you can call

   * the GetBoundingMetrics() method.

   * Note that for a frame with nested children, the bounding metrics

   * will exactly enclose its children. For example, the bounding metrics

   * of msub is the smallest rectangle that exactly encloses both the

   * base and the subscript.

   */

  NS_IMETHOD

  GetBoundingMetrics(nsBoundingMetrics& aBoundingMetrics) = 0;

  NS_IMETHOD

  SetBoundingMetrics(const nsBoundingMetrics& aBoundingMetrics) = 0;

  NS_IMETHOD

  SetReference(const nsPoint& aReference) = 0;

  virtual eMathMLFrameType GetMathMLFrameType() = 0;

  /* SUPPORT FOR STRETCHY ELEMENTS */

  /*====================================================================*/

  /* Stretch :

   * Called to ask a stretchy MathML frame to stretch itself depending

   * on its context.

   *

   * An embellished frame is treated in a special way. When it receives a

   * Stretch() command, it passes the command to its embellished child and

   * the stretched size is bubbled up from the inner-most <mo> frame. In other

   * words, the stretch command descend through the embellished hierarchy.

   *

   * @param aStretchDirection [in] the direction where to attempt to

   *        stretch.

   * @param aContainerSize [in] struct that suggests the maximumn size for

   *        the stretched frame. Only member data of the struct that are

   *        relevant to the direction are used (the rest is ignored).

   * @param aDesiredStretchSize [in/out] On input the current size

   *        of the frame, on output the size after stretching.

   */

  NS_IMETHOD

  Stretch(mozilla::gfx::DrawTarget* aDrawTarget,

          nsStretchDirection aStretchDirection,

          nsBoundingMetrics& aContainerSize,

          mozilla::ReflowOutput& aDesiredStretchSize) = 0;

  /* Get the mEmbellishData member variable. */

  NS_IMETHOD

  GetEmbellishData(nsEmbellishData& aEmbellishData) = 0;

  /* SUPPORT FOR SCRIPTING ELEMENTS */

  /*====================================================================*/

  /* Get the mPresentationData member variable. */

  NS_IMETHOD

  GetPresentationData(nsPresentationData& aPresentationData) = 0;

  /* InheritAutomaticData() / TransmitAutomaticData() :

   * There are precise rules governing each MathML frame and its children.

   * Properties such as the scriptlevel or the embellished nature of a frame

   * depend on those rules. Also, certain properties that we use to emulate

   * TeX rendering rules are frame-dependent too. These two methods are meant

   * to be implemented by frame classes that need to assert specific properties

   * within their subtrees.

   *

   * InheritAutomaticData() is called in a top-down manner [like

   * nsIFrame::Init], as we descend the frame tree, whereas

   * TransmitAutomaticData() is called in a bottom-up manner, as we ascend the

   * tree [like nsIFrame::SetInitialChildList]. However, unlike Init() and

   * SetInitialChildList() which are called only once during the life-time of a

   * frame (when initially constructing the frame tree), these two methods are

   * called to build automatic data after the <math>...</math> subtree has been

   * constructed fully, and are called again as we walk a child's subtree to

   * handle dynamic changes that happen in the content model.

   *

   * As a rule of thumb:

   *

   * 1. Use InheritAutomaticData() to set properties related to your ancestors:

   *    - set properties that are intrinsic to yourself

   *    - set properties that depend on the state that you expect your ancestors

   *      to have already reached in their own InheritAutomaticData().

   *    - set properties that your descendants assume that you would have set in

   *      your InheritAutomaticData() -- this way, they can safely query them

   * and the process will feed upon itself.

   *

   * 2. Use TransmitAutomaticData() to set properties related to your

   * descendants:

   *    - set properties that depend on the state that you expect your

   * descendants to have reached upon processing their own

   * TransmitAutomaticData().

   *    - transmit properties that your descendants expect that you will

   * transmit to them in your TransmitAutomaticData() -- this way, they remain

   * up-to-date.

   *    - set properties that your ancestors expect that you would set in your

   *      TransmitAutomaticData() -- this way, they can safely query them and

   * the process will feed upon itself.

   */

  NS_IMETHOD

  InheritAutomaticData(nsIFrame* aParent) = 0;

  NS_IMETHOD

  TransmitAutomaticData() = 0;

  /* UpdatePresentationData:

   * Updates the frame's compression flag.

   * A frame becomes "compressed" (or "cramped") according to TeX rendering

   * rules (TeXBook, Ch.17, p.140-141).

   *

   * @param aFlagsValues [in]

   *        The new values (e.g., compress) that are going to be

   *        updated.

   *

   * @param aWhichFlags [in]

   *        The flags that are relevant to this call. Since not all calls

   *        are meant to update all flags at once, aWhichFlags is used

   *        to distinguish flags that need to retain their existing values

   *        from flags that need to be turned on (or turned off). If a bit

   *        is set in aWhichFlags, then the corresponding value (which

   *        can be 0 or 1) is taken from aFlagsValues and applied to the

   *        frame. Therefore, by setting their bits in aWhichFlags, and

   *        setting their desired values in aFlagsValues, it is possible to

   *        update some flags in the frame, leaving the other flags unchanged.

   */

  NS_IMETHOD

  UpdatePresentationData(uint32_t aFlagsValues, uint32_t aWhichFlags) = 0;

  /* UpdatePresentationDataFromChildAt :

   * Sets compression flag on the whole tree. For child frames

   * at aFirstIndex up to aLastIndex, this method sets their

   * compression flags. The update is propagated down the subtrees of each of

   * these child frames.

   *

   * @param aFirstIndex [in]

   *        Index of the first child from where the update is propagated.

   *

   * @param aLastIndex [in]

   *        Index of the last child where to stop the update.

   *        A value of -1 means up to last existing child.

   *

   * @param aFlagsValues [in]

   *        The new values (e.g., compress) that are going to be

   *        assigned in the whole sub-trees.

   *

   * @param aWhichFlags [in]

   *        The flags that are relevant to this call. See

   * UpdatePresentationData() for more details about this parameter.

   */

  NS_IMETHOD

  UpdatePresentationDataFromChildAt(int32_t aFirstIndex, int32_t aLastIndex,

                                    uint32_t aFlagsValues,

                                    uint32_t aWhichFlags) = 0;

  // If aFrame is a child frame, returns the script increment which this frame

  // imposes on the specified frame, ignoring any artificial adjustments to

  // scriptlevel.

  // Returns 0 if the specified frame isn't a child frame.

  virtual uint8_t ScriptIncrement(nsIFrame* aFrame) = 0;

  // Returns true if the frame is considered to be an mrow for layout purposes.

  // This includes inferred mrows, but excludes <mrow> elements with a single

  // child.  In the latter case, the child is to be treated as if it wasn't

  // within an mrow, so we pretend the mrow isn't mrow-like.

  virtual bool IsMrowLike() = 0;

};

// struct used by a container frame to keep track of its embellishments.

// By convention, the data that we keep here is bubbled from the embellished

// hierarchy, and it remains unchanged unless we have to recover from a change

// that occurs in the embellished hierarchy. The struct remains in its nil

// state in those frames that are not part of the embellished hierarchy.

struct nsEmbellishData {

  // bits used to mark certain properties of our embellishments

  uint32_t flags;

  // pointer on the <mo> frame at the core of the embellished hierarchy

  nsIFrame* coreFrame;

  // stretchy direction that the nsMathMLChar owned by the core <mo> supports

  nsStretchDirection direction;

  // spacing that may come from <mo> depending on its 'form'. Since

  // the 'form' may also depend on the position of the outermost

  // embellished ancestor, the set up of these values may require

  // looking up the position of our ancestors.

  nscoord leadingSpace;

  nscoord trailingSpace;

  nsEmbellishData() {

    flags = 0;

    coreFrame = nullptr;

    direction = NS_STRETCH_DIRECTION_UNSUPPORTED;

    leadingSpace = 0;

    trailingSpace = 0;

  }

};

// struct used by a container frame to modulate its presentation.

// By convention, the data that we keep in this struct can change depending

// on any of our ancestors and/or descendants. If a data can be resolved

// solely from the embellished hierarchy, and it remains immutable once

// resolved, we put it in |nsEmbellishData|. If it can be affected by other

// things, it comes here. This struct is updated as we receive information

// transmitted by our ancestors and is kept in sync with changes in our

// descendants that affects us.

struct nsPresentationData {

  // bits for: compressed, etc

  uint32_t flags;

  // handy pointer on our base child (the 'nucleus' in TeX), but it may be

  // null here (e.g., tags like <mrow>, <mfrac>, <mtable>, etc, won't

  // pick a particular child in their child list to be the base)

  nsIFrame* baseFrame;

  nsPresentationData() {

    flags = 0;

    baseFrame = nullptr;

  }

};

// ==========================================================================

// Bits used for the presentation flags -- these bits are set

// in their relevant situation as they become available

// This bit is used to emulate TeX rendering.

// Internal use only, cannot be set by the user with an attribute.

#define NS_MATHML_COMPRESSED 0x00000002U

// This bit is set if the frame will fire a vertical stretch

// command on all its (non-empty) children.

// Tags like <mrow> (or an inferred mrow), mpadded, etc, will fire a

// vertical stretch command on all their non-empty children

#define NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY 0x00000004U

// This bit is set if the frame will fire a horizontal stretch

// command on all its (non-empty) children.

// Tags like munder, mover, munderover, will fire a

// horizontal stretch command on all their non-empty children

#define NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY 0x00000008U

// This bit is set if the frame is "space-like", as defined by the spec.

#define NS_MATHML_SPACE_LIKE 0x00000040U

// This bit is set if a token frame should be rendered with the dtls font

// feature setting.

#define NS_MATHML_DTLS 0x00000080U

// This bit is set when the frame cannot be formatted due to an

// error (e.g., invalid markup such as a <msup> without an overscript).

// When set, a visual feedback will be provided to the user.

#define NS_MATHML_ERROR 0x80000000U

// a bit used for debug

#define NS_MATHML_STRETCH_DONE 0x20000000U

// This bit is used for visual debug. When set, the bounding box

// of your frame is painted. This visual debug enable to ensure that

// you have properly filled your mReference and mBoundingMetrics in

// Place().

#define NS_MATHML_SHOW_BOUNDING_METRICS 0x10000000U

// Macros that retrieve those bits

#define NS_MATHML_IS_COMPRESSED(_flags) \

  (NS_MATHML_COMPRESSED == ((_flags)&NS_MATHML_COMPRESSED))

#define NS_MATHML_WILL_STRETCH_ALL_CHILDREN_VERTICALLY(_flags) \

  (NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY ==                \

   ((_flags)&NS_MATHML_STRETCH_ALL_CHILDREN_VERTICALLY))

#define NS_MATHML_WILL_STRETCH_ALL_CHILDREN_HORIZONTALLY(_flags) \

  (NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY ==                \

   ((_flags)&NS_MATHML_STRETCH_ALL_CHILDREN_HORIZONTALLY))

#define NS_MATHML_IS_SPACE_LIKE(_flags) \

  (NS_MATHML_SPACE_LIKE == ((_flags)&NS_MATHML_SPACE_LIKE))

#define NS_MATHML_IS_DTLS_SET(_flags) \

  (NS_MATHML_DTLS == ((_flags)&NS_MATHML_DTLS))

#define NS_MATHML_HAS_ERROR(_flags) \

  (NS_MATHML_ERROR == ((_flags)&NS_MATHML_ERROR))

#define NS_MATHML_STRETCH_WAS_DONE(_flags) \

  (NS_MATHML_STRETCH_DONE == ((_flags)&NS_MATHML_STRETCH_DONE))

#define NS_MATHML_PAINT_BOUNDING_METRICS(_flags) \

  (NS_MATHML_SHOW_BOUNDING_METRICS ==            \

   ((_flags)&NS_MATHML_SHOW_BOUNDING_METRICS))

// ==========================================================================

// Bits used for the embellish flags -- these bits are set

// in their relevant situation as they become available

// This bit is set if the frame is an embellished operator.

#define NS_MATHML_EMBELLISH_OPERATOR 0x00000001

// This bit is set if the frame is an <mo> frame or an embellihsed

// operator for which the core <mo> has movablelimits="true"

#define NS_MATHML_EMBELLISH_MOVABLELIMITS 0x00000002

// This bit is set if the frame is an <mo> frame or an embellihsed

// operator for which the core <mo> has accent="true"

#define NS_MATHML_EMBELLISH_ACCENT 0x00000004

// This bit is set if the frame is an <mover> or <munderover> with

// an accent frame

#define NS_MATHML_EMBELLISH_ACCENTOVER 0x00000008

// This bit is set if the frame is an <munder> or <munderover> with

// an accentunder frame

#define NS_MATHML_EMBELLISH_ACCENTUNDER 0x00000010

// This bit is set on the core if it is a fence operator.

#define NS_MATHML_EMBELLISH_FENCE 0x00000020

// This bit is set on the core if it is a separator operator.

#define NS_MATHML_EMBELLISH_SEPARATOR 0x00000040

// Macros that retrieve those bits

#define NS_MATHML_IS_EMBELLISH_OPERATOR(_flags) \

  (NS_MATHML_EMBELLISH_OPERATOR == ((_flags)&NS_MATHML_EMBELLISH_OPERATOR))

#define NS_MATHML_EMBELLISH_IS_MOVABLELIMITS(_flags) \

  (NS_MATHML_EMBELLISH_MOVABLELIMITS ==              \

   ((_flags)&NS_MATHML_EMBELLISH_MOVABLELIMITS))

#define NS_MATHML_EMBELLISH_IS_ACCENT(_flags) \

  (NS_MATHML_EMBELLISH_ACCENT == ((_flags)&NS_MATHML_EMBELLISH_ACCENT))

#define NS_MATHML_EMBELLISH_IS_ACCENTOVER(_flags) \

  (NS_MATHML_EMBELLISH_ACCENTOVER == ((_flags)&NS_MATHML_EMBELLISH_ACCENTOVER))

#define NS_MATHML_EMBELLISH_IS_ACCENTUNDER(_flags) \

  (NS_MATHML_EMBELLISH_ACCENTUNDER ==              \

   ((_flags)&NS_MATHML_EMBELLISH_ACCENTUNDER))

#define NS_MATHML_EMBELLISH_IS_FENCE(_flags) \

  (NS_MATHML_EMBELLISH_FENCE == ((_flags)&NS_MATHML_EMBELLISH_FENCE))

#define NS_MATHML_EMBELLISH_IS_SEPARATOR(_flags) \

  (NS_MATHML_EMBELLISH_SEPARATOR == ((_flags)&NS_MATHML_EMBELLISH_SEPARATOR))

#endif /* nsIMathMLFrame_h___ */