pjs/layout/tables/BasicTableLayoutStrategy.h

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
 *
 * The contents of this file are subject to the Netscape Public License
 * Version 1.0 (the "NPL"); you may not use this file except in
 * compliance with the NPL.  You may obtain a copy of the NPL at
 * http://www.mozilla.org/NPL/
 *
 * Software distributed under the NPL is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
 * for the specific language governing rights and limitations under the
 * NPL.
 *
 * The Initial Developer of this code under the NPL is Netscape
 * Communications Corporation.  Portions created by Netscape are
 * Copyright (C) 1998 Netscape Communications Corporation.  All Rights
 * Reserved.
 */

#ifndef BasicTableLayoutStrategy_h__
#define BasicTableLayoutStrategy_h__

#include "nscore.h"
#include "nsITableLayoutStrategy.h"
#include "nsCoord.h"

class nsVoidArray;
class nsTableFrame;
struct nsStylePosition;
struct nsStyleTable;

static const PRInt32 kUninitialized=-1;

/* ---------- BasicTableLayoutStrategy ---------- */

/** Implementation of Nav4 compatible HTML browser table layout.
  * The input to this class is the results from pass1 table layout.
  * The output from this class is to set the column widths in
  * mTableFrame.
  */
class BasicTableLayoutStrategy : public nsITableLayoutStrategy
{
public:

  /** Public constructor.
    * @paran aFrame           the table frame for which this delegate will do layout
    */
  BasicTableLayoutStrategy(nsTableFrame *aFrame,
                           PRBool        aIsNavQuirksMode = PR_TRUE);

  /** destructor */
  virtual ~BasicTableLayoutStrategy();

  /** call every time any table thing changes that might effect the width of any column
    * in the table (content, structure, or style) 
    * @param aMaxElementSize  [OUT] if not null, the max element size is computed and returned in this param
    * @param aNumCols         the total number of columns in the table
    */
  virtual PRBool Initialize(nsSize* aMaxElementSize, PRInt32 aNumCols, nscoord aMaxSize);

  /** compute the max element size of the table.
    * assumes that Initialize has been called
    */
  virtual void SetMaxElementSize(nsSize* aMaxElementSize);

  void SetMinAndMaxTableContentWidths();

  /** Called during resize reflow to determine the new column widths
    * @param aTableStyle - the resolved style for mTableFrame
	  * @param aReflowState - the reflow state for mTableFrame
 	  * @param aMaxWidth - the computed max width for columns to fit into
	  */
  virtual PRBool BalanceColumnWidths(nsIStyleContext*         aTableStyle,
                                     const nsHTMLReflowState& aReflowState,
                                     nscoord                  aMaxWidth);

  // these accessors are mostly for debugging purposes
  nscoord GetTableMinContentWidth() const;
  nscoord GetTableMaxContentWidth() const;
  nscoord GetCOLSAttribute() const;
  nscoord GetNumCols() const;
  void Dump(PRInt32 aIndent);

protected:

  /** assign widths for each column.
    * if the column has a fixed coord width, use it.
    * if the column includes col spanning cells, 
    * then distribute the fixed space between cells proportionately.
    * Computes the minimum and maximum table widths. 
    * Set column width information in each column frame and in the table frame.
    *
    * @param aMaxWidth - the computed width of the table or 
    *  UNCONSTRAINED_SIZE if an auto width table
    * @return PR_TRUE if all is well, PR_FALSE if there was an unrecoverable error
    *
    */
  virtual PRBool AssignPreliminaryColumnWidths(nscoord aComputedWidth);

  nscoord AssignPercentageColumnWidths(nscoord aBasis,
                                       PRBool  aTableIsAutoWidth);

  void CalculateTotals(PRInt32& aCellSpacing,
                       PRInt32* aTotalCounts,
                       PRInt32* aTotalWidths,
                       PRInt32* aMinWidths,
                       PRInt32& a0ProportionalCount);

  void AllocateFully(nscoord& aTotalAllocated,
                     PRInt32* aAllocTypes,
                     PRInt32  aWidthType,
                     PRBool   aMarkAllocated = PR_TRUE);

  void AllocateConstrained(PRInt32  aAvailWidth,
                           PRInt32  aWidthType,
                           PRInt32  aNumConstrainedCols,
                           PRInt32  aSumMaxConstraints,
                           PRBool   aStartAtMin,        
                           PRInt32* aAllocTypes);

  void AllocateUnconstrained(PRInt32  aAllocAmount,
                             PRInt32* aAllocTypes,
                             PRBool   aSkip0Proportional);

  /** return true if the style indicates that the width is a specific width 
    * for the purposes of column width determination.
    * return false if the width changes based on content, parent size, etc.
    */
  static PRBool IsFixedWidth(const nsStylePosition* aStylePosition,
                              const nsStyleTable* aStyleTable);

  /** return true if the colIndex is in the list of colIndexes */
  virtual PRBool IsColumnInList(const PRInt32 colIndex, 
                                PRInt32 *colIndexes, 
                                PRInt32 aNumFixedColumns);

  /** returns true if the column is specified to have its min width */
  virtual PRBool ColIsSpecifiedAsMinimumWidth(PRInt32 aColIndex);

  /** eturns a list and count of all columns that behave like they have width=auto
    * this includes columns with no width specified (the normal definition of "auto"), 
    * columns explicitly set to auto width, 
    * and columns whose fixed width comes from a span (meaning the real width is indeterminate.)
    *
    * @param aOutNumColumns -- out param, the number of columns matching aType
    * @param aOutColumnIndexes -- out param, the indexes of the columns matching aType
    *                             
    * @return       aOutNumColumns set to the number of auto columns, may be 0
    *               allocates and fills aOutColumnIndexes
    *               caller must "delete [] aOutColumnIndexes" if it is not null
    */
  void GetColumnsThatActLikeAutoWidth(PRInt32&  aOutNumColumns,
                                      PRInt32*& aOutColumnIndexes);
  void ContinuingFrameCheck();

protected:
  nsTableFrame * mTableFrame;
  PRInt32        mCols;
  PRInt32        mNumCols;
  // cached data
  nscoord        mMinTableContentWidth;   // the smallest size for the table (excluding border and padding)
  nscoord        mMaxTableContentWidth;   // the "natural" size for the table, if unconstrained (excluding border and padding) 
  nscoord        mCellSpacingTotal;       // all of the cellspacing for all of the cols
  float          mMinToDesProportionRatio;
  PRPackedBool   mIsNavQuirksMode;
};

// these accessors are mostly for debugging purposes
inline nscoord BasicTableLayoutStrategy::GetTableMinContentWidth() const
{ return mMinTableContentWidth; };

inline nscoord BasicTableLayoutStrategy::GetTableMaxContentWidth() const
{ return mMaxTableContentWidth; };

inline nscoord BasicTableLayoutStrategy::GetCOLSAttribute() const
{ return mCols; };

inline nscoord BasicTableLayoutStrategy::GetNumCols() const
{ return mNumCols; };  


#endif