src/html/m_layout.cpp

/////////////////////////////////////////////////////////////////////////////
// Name:        m_layout.cpp
// Purpose:     wxHtml module for basic paragraphs/layout handling
// Author:      Vaclav Slavik
// RCS-ID:      $Id$
// Copyright:   (c) 1999 Vaclav Slavik
// Licence:     wxWindows Licence
/////////////////////////////////////////////////////////////////////////////
#ifdef __GNUG__
#pragma implementation
#endif

#include "wx/wxprec.h"


#include "wx/defs.h"
#if wxUSE_HTML && wxUSE_STREAMS
#ifdef __BORLANDC__
#pragma hdrstop
#endif

#ifndef WXPRECOMP
#endif


#include "wx/html/forcelnk.h"
#include "wx/html/m_templ.h"

#include "wx/html/htmlwin.h"

FORCE_LINK_ME(m_layout)


#include <stdlib.h> // bsearch()

//-----------------------------------------------------------------------------
// wxHtmlPageBreakCell
//-----------------------------------------------------------------------------

// Since html isn't a page-layout language, it doesn't support page
// page breaks directly--that requires CSS2 support. But a page-break
// facility is handy, and has been requested more than once on the
// mailing lists. This wxHtml tag handler implements just enough of
// CSS2 to support a page break by recognizing only
//   <div style="page-break-before:always">
//
// wxHtml maintains page breaks in wxHtmlPrintout::m_PageBreaks. The
// tag handler below adds appropriate offsets to that array member.
// wxHtmlDCRenderer::Render() accesses that array and makes a new page
// begin after each page-break tag.

// The page-break handler does all its work in AdjustPagebreak(). For
// all tag handlers, that function adjusts the page-break position.
// For other tags, it determines whether the html element can fit on
// the remainder of the page; if it cannot fit, but must not be split,
// then the function moves the page break provided in the argument up,
// and returns 'true' to inform the caller that the argument was
// modified.
//
// Due to its special purpose, the page-break facility differs from
// other tags. It takes up no space, but it behaves as though there is
// never enough room to fit it on the remainder of the page--it always
// forces a page break. Therefore, unlike other elements that trigger
// a page break, it would never 'fit' on the following page either.
// Therefore it's necessary to compare each pagebreak candidate to the
// array wxHtmlPrintout::m_PageBreaks of pagebreaks already set, and
// set a new one only if it's not in that array.

class WXDLLEXPORT wxHtmlPageBreakCell : public wxHtmlCell
{
  public:
    wxHtmlPageBreakCell() {}

    bool AdjustPagebreak(int* pagebreak, int* known_pagebreaks = NULL, int number_of_pages = 0) const;

  private:
    DECLARE_NO_COPY_CLASS(wxHtmlPageBreakCell)
};

// Comparison routine for bsearch into an int* array of pagebreaks.
static int integer_compare(void const* i0, void const* i1)
{
    return *(int*)i0 - *(int*)i1;
}

bool wxHtmlPageBreakCell::AdjustPagebreak(int* pagebreak, int* known_pagebreaks, int number_of_pages) const
{
    // When we are counting pages, 'known_pagebreaks' is non-NULL.
    // That's the only time we change 'pagebreak'. Otherwise, pages
    // were already counted, 'known_pagebreaks' is NULL, and we don't
    // do anything except return FALSE.
    //
    // We also simply return FALSE if the 'pagebreak' argument is
    // less than (vertically above) or the same as the current
    // vertical position. Otherwise we'd be setting a pagebreak above
    // the current cell, which is incorrect, or duplicating a
    // pagebreak that has already been set.
    if(NULL == known_pagebreaks || *pagebreak <= m_PosY)
        {
        return FALSE;
        }

    // m_PosY is only the vertical offset from the parent. The pagebreak
    // required here is the total page offset, so m_PosY must be added
    // to the parent's offset and height.
    int total_height = m_PosY + GetParent()->GetPosY() + GetParent()->GetHeight();

    // Search the array of pagebreaks to see whether we've already set
    // a pagebreak here. The standard bsearch() function is appropriate
    // because the array of pagebreaks through known_pagebreaks[number_of_pages]
    // is known to be sorted in strictly increasing order. '1 + number_of_pages'
    // is used as a bsearch() argument because the array contains a leading
    // zero plus one element for each page.
    int* where = (int*) bsearch(&total_height, known_pagebreaks,
                                1 + number_of_pages, sizeof(int),
                                integer_compare);
    // Add a pagebreak only if there isn't one already set here.
    if(NULL != where)
        {
        return FALSE;
        }
    else
        {
        *pagebreak = m_PosY;
        return TRUE;
        }
}

TAG_HANDLER_BEGIN(P, "P")

    TAG_HANDLER_PROC(tag)
    {
        if (m_WParser->GetContainer()->GetFirstCell() != NULL)
        {
            m_WParser->CloseContainer();
            m_WParser->OpenContainer();
        }
        m_WParser->GetContainer()->SetIndent(m_WParser->GetCharHeight(), wxHTML_INDENT_TOP);
        m_WParser->GetContainer()->SetAlign(tag);
        return FALSE;
    }

TAG_HANDLER_END(P)


TAG_HANDLER_BEGIN(BR, "BR")

    TAG_HANDLER_PROC(tag)
    {
        int al = m_WParser->GetContainer()->GetAlignHor();
        wxHtmlContainerCell *c;

        m_WParser->CloseContainer();
        c = m_WParser->OpenContainer();
        c->SetAlignHor(al);
        c->SetAlign(tag);
        c->SetMinHeight(m_WParser->GetCharHeight());
        return FALSE;
    }

TAG_HANDLER_END(BR)


TAG_HANDLER_BEGIN(CENTER, "CENTER")

    TAG_HANDLER_PROC(tag)
    {
        int old = m_WParser->GetAlign();
        wxHtmlContainerCell *c = m_WParser->GetContainer();

        m_WParser->SetAlign(wxHTML_ALIGN_CENTER);
        if (c->GetFirstCell() != NULL)
        {
            m_WParser->CloseContainer();
            m_WParser->OpenContainer();
        }
        else
            c->SetAlignHor(wxHTML_ALIGN_CENTER);

        if (tag.HasEnding())
        {
            ParseInner(tag);

            m_WParser->SetAlign(old);
            if (c->GetFirstCell() != NULL)
            {
                m_WParser->CloseContainer();
                m_WParser->OpenContainer();
            }
            else
                c->SetAlignHor(old);

            return TRUE;
        }
        else return FALSE;
    }

TAG_HANDLER_END(CENTER)


TAG_HANDLER_BEGIN(DIV, "DIV")

    TAG_HANDLER_PROC(tag)
    {
        if(tag.HasParam(wxT("STYLE")))
        {
            if(tag.GetParam(wxT("STYLE")).IsSameAs(wxT("PAGE-BREAK-BEFORE:ALWAYS"), FALSE))
            {
                m_WParser->CloseContainer();
                m_WParser->OpenContainer()->InsertCell(new wxHtmlPageBreakCell);
                m_WParser->CloseContainer();
                m_WParser->OpenContainer();
                return FALSE;
            }
            else
            {
                // Treat other STYLE parameters here when they're supported.
                return FALSE;
            }
        }
        else if(tag.HasParam(wxT("ALIGN")))
        {
            int old = m_WParser->GetAlign();
            wxHtmlContainerCell *c = m_WParser->GetContainer();
            if (c->GetFirstCell() != NULL)
            {
                m_WParser->CloseContainer();
                m_WParser->OpenContainer();
                c = m_WParser->GetContainer();
                c->SetAlign(tag);
                m_WParser->SetAlign(c->GetAlignHor());
            }
            else
            {
                c->SetAlign(tag);
                m_WParser->SetAlign(c->GetAlignHor());
            }

            ParseInner(tag);

            m_WParser->SetAlign(old);
            if (c->GetFirstCell() != NULL)
            {
                m_WParser->CloseContainer();
                m_WParser->OpenContainer();
            }
            else
                c->SetAlignHor(old);

            return TRUE;
        }
        else
        {
            return FALSE;
        }
    }

TAG_HANDLER_END(DIV)


TAG_HANDLER_BEGIN(TITLE, "TITLE")

    TAG_HANDLER_PROC(tag)
    {
        if (m_WParser->GetWindow())
        {
            wxHtmlWindow *wfr = (wxHtmlWindow*)(m_WParser->GetWindow());
            if (wfr)
            {
                const wxString& src = *m_WParser->GetSource();
                wfr->OnSetTitle(src.Mid(tag.GetBeginPos(),
                                        tag.GetEndPos1()-tag.GetBeginPos()));
            }
        }
        return TRUE;
    }

TAG_HANDLER_END(TITLE)


TAG_HANDLER_BEGIN(BODY, "BODY")

    TAG_HANDLER_PROC(tag)
    {
        wxColour clr;

        if (tag.GetParamAsColour(wxT("TEXT"), &clr))
        {
            m_WParser->SetActualColor(clr);
            m_WParser->GetContainer()->InsertCell(new wxHtmlColourCell(clr));
        }

        if (tag.GetParamAsColour(wxT("LINK"), &clr))
            m_WParser->SetLinkColor(clr);

        if (tag.GetParamAsColour(wxT("BGCOLOR"), &clr))
        {
            m_WParser->GetContainer()->InsertCell(
                new wxHtmlColourCell(clr, wxHTML_CLR_BACKGROUND));
            if (m_WParser->GetWindow() != NULL)
                m_WParser->GetWindow()->SetBackgroundColour(clr);
        }
        return FALSE;
    }

TAG_HANDLER_END(BODY)


TAG_HANDLER_BEGIN(BLOCKQUOTE, "BLOCKQUOTE")

    TAG_HANDLER_PROC(tag)
    {
        wxHtmlContainerCell *c;

        m_WParser->CloseContainer();
        c = m_WParser->OpenContainer();

        if (c->GetAlignHor() == wxHTML_ALIGN_RIGHT)
            c->SetIndent(5 * m_WParser->GetCharWidth(), wxHTML_INDENT_RIGHT);
        else
            c->SetIndent(5 * m_WParser->GetCharWidth(), wxHTML_INDENT_LEFT);

        c->SetIndent(m_WParser->GetCharHeight(), wxHTML_INDENT_TOP);
        m_WParser->OpenContainer();
        ParseInner(tag);
        c = m_WParser->CloseContainer();
        c->SetIndent(m_WParser->GetCharHeight(), wxHTML_INDENT_BOTTOM);
        m_WParser->CloseContainer();
        m_WParser->OpenContainer();
        return TRUE;
    }

TAG_HANDLER_END(BLOCKQUOTE)


// Tag handler for tags that we have to ignore, otherwise non-text data
// would show up as text:
TAG_HANDLER_BEGIN(DoNothing, "SCRIPT")
    TAG_HANDLER_PROC(tag)
    {
        return true;
    }
TAG_HANDLER_END(DoNothing)


TAGS_MODULE_BEGIN(Layout)

    TAGS_MODULE_ADD(P)
    TAGS_MODULE_ADD(BR)
    TAGS_MODULE_ADD(CENTER)
    TAGS_MODULE_ADD(DIV)
    TAGS_MODULE_ADD(TITLE)
    TAGS_MODULE_ADD(BODY)
    TAGS_MODULE_ADD(BLOCKQUOTE)
    TAGS_MODULE_ADD(DoNothing)

TAGS_MODULE_END(Layout)

#endif
Commit	Line	Data
	1	/////////////////////////////////////////////////////////////////////////////
	2	// Name: m_layout.cpp
	3	// Purpose: wxHtml module for basic paragraphs/layout handling
	4	// Author: Vaclav Slavik
	5	// RCS-ID: $Id$
	6	// Copyright: (c) 1999 Vaclav Slavik
	7	// Licence: wxWindows Licence
	8	/////////////////////////////////////////////////////////////////////////////
	9	#ifdef __GNUG__
	10	#pragma implementation
	11	#endif
	12
	13	#include "wx/wxprec.h"
	14
	15
	16	#include "wx/defs.h"
	17	#if wxUSE_HTML && wxUSE_STREAMS
	18	#ifdef __BORLANDC__
	19	#pragma hdrstop
	20	#endif
	21
	22	#ifndef WXPRECOMP
	23	#endif
	24
	25
	26	#include "wx/html/forcelnk.h"
	27	#include "wx/html/m_templ.h"
	28
	29	#include "wx/html/htmlwin.h"
	30
	31	FORCE_LINK_ME(m_layout)
	32
	33
	34	#include <stdlib.h> // bsearch()
	35
	36	//-----------------------------------------------------------------------------
	37	// wxHtmlPageBreakCell
	38	//-----------------------------------------------------------------------------
	39
	40	// Since html isn't a page-layout language, it doesn't support page
	41	// page breaks directly--that requires CSS2 support. But a page-break
	42	// facility is handy, and has been requested more than once on the
	43	// mailing lists. This wxHtml tag handler implements just enough of
	44	// CSS2 to support a page break by recognizing only
	45	// <div style="page-break-before:always">
	46	//
	47	// wxHtml maintains page breaks in wxHtmlPrintout::m_PageBreaks. The
	48	// tag handler below adds appropriate offsets to that array member.
	49	// wxHtmlDCRenderer::Render() accesses that array and makes a new page
	50	// begin after each page-break tag.
	51
	52	// The page-break handler does all its work in AdjustPagebreak(). For
	53	// all tag handlers, that function adjusts the page-break position.
	54	// For other tags, it determines whether the html element can fit on
	55	// the remainder of the page; if it cannot fit, but must not be split,
	56	// then the function moves the page break provided in the argument up,
	57	// and returns 'true' to inform the caller that the argument was
	58	// modified.
	59	//
	60	// Due to its special purpose, the page-break facility differs from
	61	// other tags. It takes up no space, but it behaves as though there is
	62	// never enough room to fit it on the remainder of the page--it always
	63	// forces a page break. Therefore, unlike other elements that trigger
	64	// a page break, it would never 'fit' on the following page either.
	65	// Therefore it's necessary to compare each pagebreak candidate to the
	66	// array wxHtmlPrintout::m_PageBreaks of pagebreaks already set, and
	67	// set a new one only if it's not in that array.
	68
	69	class WXDLLEXPORT wxHtmlPageBreakCell : public wxHtmlCell
	70	{
	71	public:
	72	wxHtmlPageBreakCell() {}
	73
	74	bool AdjustPagebreak(int* pagebreak, int* known_pagebreaks = NULL, int number_of_pages = 0) const;
	75
	76	private:
	77	DECLARE_NO_COPY_CLASS(wxHtmlPageBreakCell)
	78	};
	79
	80	// Comparison routine for bsearch into an int* array of pagebreaks.
	81	static int integer_compare(void const* i0, void const* i1)
	82	{
	83	return (int)i0 - (int)i1;
	84	}
	85
	86	bool wxHtmlPageBreakCell::AdjustPagebreak(int* pagebreak, int* known_pagebreaks, int number_of_pages) const
	87	{
	88	// When we are counting pages, 'known_pagebreaks' is non-NULL.
	89	// That's the only time we change 'pagebreak'. Otherwise, pages
	90	// were already counted, 'known_pagebreaks' is NULL, and we don't
	91	// do anything except return FALSE.
	92	//
	93	// We also simply return FALSE if the 'pagebreak' argument is
	94	// less than (vertically above) or the same as the current
	95	// vertical position. Otherwise we'd be setting a pagebreak above
	96	// the current cell, which is incorrect, or duplicating a
	97	// pagebreak that has already been set.
	98	if(NULL == known_pagebreaks \|\| *pagebreak <= m_PosY)
	99	{
	100	return FALSE;
	101	}
	102
	103	// m_PosY is only the vertical offset from the parent. The pagebreak
	104	// required here is the total page offset, so m_PosY must be added
	105	// to the parent's offset and height.
	106	int total_height = m_PosY + GetParent()->GetPosY() + GetParent()->GetHeight();
	107
	108	// Search the array of pagebreaks to see whether we've already set
	109	// a pagebreak here. The standard bsearch() function is appropriate
	110	// because the array of pagebreaks through known_pagebreaks[number_of_pages]
	111	// is known to be sorted in strictly increasing order. '1 + number_of_pages'
	112	// is used as a bsearch() argument because the array contains a leading
	113	// zero plus one element for each page.
	114	int* where = (int*) bsearch(&total_height, known_pagebreaks,
	115	1 + number_of_pages, sizeof(int),
	116	integer_compare);
	117	// Add a pagebreak only if there isn't one already set here.
	118	if(NULL != where)
	119	{
	120	return FALSE;
	121	}
	122	else
	123	{
	124	*pagebreak = m_PosY;
	125	return TRUE;
	126	}
	127	}
	128
	129	TAG_HANDLER_BEGIN(P, "P")
	130
	131	TAG_HANDLER_PROC(tag)
	132	{
	133	if (m_WParser->GetContainer()->GetFirstCell() != NULL)
	134	{
	135	m_WParser->CloseContainer();
	136	m_WParser->OpenContainer();
	137	}
	138	m_WParser->GetContainer()->SetIndent(m_WParser->GetCharHeight(), wxHTML_INDENT_TOP);
	139	m_WParser->GetContainer()->SetAlign(tag);
	140	return FALSE;
	141	}
	142
	143	TAG_HANDLER_END(P)
	144
	145
	146
	147	TAG_HANDLER_BEGIN(BR, "BR")
	148
	149	TAG_HANDLER_PROC(tag)
	150	{
	151	int al = m_WParser->GetContainer()->GetAlignHor();
	152	wxHtmlContainerCell *c;
	153
	154	m_WParser->CloseContainer();
	155	c = m_WParser->OpenContainer();
	156	c->SetAlignHor(al);
	157	c->SetAlign(tag);
	158	c->SetMinHeight(m_WParser->GetCharHeight());
	159	return FALSE;
	160	}
	161
	162	TAG_HANDLER_END(BR)
	163
	164
	165
	166	TAG_HANDLER_BEGIN(CENTER, "CENTER")
	167
	168	TAG_HANDLER_PROC(tag)
	169	{
	170	int old = m_WParser->GetAlign();
	171	wxHtmlContainerCell *c = m_WParser->GetContainer();
	172
	173	m_WParser->SetAlign(wxHTML_ALIGN_CENTER);
	174	if (c->GetFirstCell() != NULL)
	175	{
	176	m_WParser->CloseContainer();
	177	m_WParser->OpenContainer();
	178	}
	179	else
	180	c->SetAlignHor(wxHTML_ALIGN_CENTER);
	181
	182	if (tag.HasEnding())
	183	{
	184	ParseInner(tag);
	185
	186	m_WParser->SetAlign(old);
	187	if (c->GetFirstCell() != NULL)
	188	{
	189	m_WParser->CloseContainer();
	190	m_WParser->OpenContainer();
	191	}
	192	else
	193	c->SetAlignHor(old);
	194
	195	return TRUE;
	196	}
	197	else return FALSE;
	198	}
	199
	200	TAG_HANDLER_END(CENTER)
	201
	202
	203
	204	TAG_HANDLER_BEGIN(DIV, "DIV")
	205
	206	TAG_HANDLER_PROC(tag)
	207	{
	208	if(tag.HasParam(wxT("STYLE")))
	209	{
	210	if(tag.GetParam(wxT("STYLE")).IsSameAs(wxT("PAGE-BREAK-BEFORE:ALWAYS"), FALSE))
	211	{
	212	m_WParser->CloseContainer();
	213	m_WParser->OpenContainer()->InsertCell(new wxHtmlPageBreakCell);
	214	m_WParser->CloseContainer();
	215	m_WParser->OpenContainer();
	216	return FALSE;
	217	}
	218	else
	219	{
	220	// Treat other STYLE parameters here when they're supported.
	221	return FALSE;
	222	}
	223	}
	224	else if(tag.HasParam(wxT("ALIGN")))
	225	{
	226	int old = m_WParser->GetAlign();
	227	wxHtmlContainerCell *c = m_WParser->GetContainer();
	228	if (c->GetFirstCell() != NULL)
	229	{
	230	m_WParser->CloseContainer();
	231	m_WParser->OpenContainer();
	232	c = m_WParser->GetContainer();
	233	c->SetAlign(tag);
	234	m_WParser->SetAlign(c->GetAlignHor());
	235	}
	236	else
	237	{
	238	c->SetAlign(tag);
	239	m_WParser->SetAlign(c->GetAlignHor());
	240	}
	241
	242	ParseInner(tag);
	243
	244	m_WParser->SetAlign(old);
	245	if (c->GetFirstCell() != NULL)
	246	{
	247	m_WParser->CloseContainer();
	248	m_WParser->OpenContainer();
	249	}
	250	else
	251	c->SetAlignHor(old);
	252
	253	return TRUE;
	254	}
	255	else
	256	{
	257	return FALSE;
	258	}
	259	}
	260
	261	TAG_HANDLER_END(DIV)
	262
	263
	264
	265
	266	TAG_HANDLER_BEGIN(TITLE, "TITLE")
	267
	268	TAG_HANDLER_PROC(tag)
	269	{
	270	if (m_WParser->GetWindow())
	271	{
	272	wxHtmlWindow wfr = (wxHtmlWindow)(m_WParser->GetWindow());
	273	if (wfr)
	274	{
	275	const wxString& src = *m_WParser->GetSource();
	276	wfr->OnSetTitle(src.Mid(tag.GetBeginPos(),
	277	tag.GetEndPos1()-tag.GetBeginPos()));
	278	}
	279	}
	280	return TRUE;
	281	}
	282
	283	TAG_HANDLER_END(TITLE)
	284
	285
	286
	287
	288	TAG_HANDLER_BEGIN(BODY, "BODY")
	289
	290	TAG_HANDLER_PROC(tag)
	291	{
	292	wxColour clr;
	293
	294	if (tag.GetParamAsColour(wxT("TEXT"), &clr))
	295	{
	296	m_WParser->SetActualColor(clr);
	297	m_WParser->GetContainer()->InsertCell(new wxHtmlColourCell(clr));
	298	}
	299
	300	if (tag.GetParamAsColour(wxT("LINK"), &clr))
	301	m_WParser->SetLinkColor(clr);
	302
	303	if (tag.GetParamAsColour(wxT("BGCOLOR"), &clr))
	304	{
	305	m_WParser->GetContainer()->InsertCell(
	306	new wxHtmlColourCell(clr, wxHTML_CLR_BACKGROUND));
	307	if (m_WParser->GetWindow() != NULL)
	308	m_WParser->GetWindow()->SetBackgroundColour(clr);
	309	}
	310	return FALSE;
	311	}
	312
	313	TAG_HANDLER_END(BODY)
	314
	315
	316
	317	TAG_HANDLER_BEGIN(BLOCKQUOTE, "BLOCKQUOTE")
	318
	319	TAG_HANDLER_PROC(tag)
	320	{
	321	wxHtmlContainerCell *c;
	322
	323	m_WParser->CloseContainer();
	324	c = m_WParser->OpenContainer();
	325
	326	if (c->GetAlignHor() == wxHTML_ALIGN_RIGHT)
	327	c->SetIndent(5 * m_WParser->GetCharWidth(), wxHTML_INDENT_RIGHT);
	328	else
	329	c->SetIndent(5 * m_WParser->GetCharWidth(), wxHTML_INDENT_LEFT);
	330
	331	c->SetIndent(m_WParser->GetCharHeight(), wxHTML_INDENT_TOP);
	332	m_WParser->OpenContainer();
	333	ParseInner(tag);
	334	c = m_WParser->CloseContainer();
	335	c->SetIndent(m_WParser->GetCharHeight(), wxHTML_INDENT_BOTTOM);
	336	m_WParser->CloseContainer();
	337	m_WParser->OpenContainer();
	338	return TRUE;
	339	}
	340
	341	TAG_HANDLER_END(BLOCKQUOTE)
	342
	343
	344
	345	// Tag handler for tags that we have to ignore, otherwise non-text data
	346	// would show up as text:
	347	TAG_HANDLER_BEGIN(DoNothing, "SCRIPT")
	348	TAG_HANDLER_PROC(tag)
	349	{
	350	return true;
	351	}
	352	TAG_HANDLER_END(DoNothing)
	353
	354
	355
	356	TAGS_MODULE_BEGIN(Layout)
	357
	358	TAGS_MODULE_ADD(P)
	359	TAGS_MODULE_ADD(BR)
	360	TAGS_MODULE_ADD(CENTER)
	361	TAGS_MODULE_ADD(DIV)
	362	TAGS_MODULE_ADD(TITLE)
	363	TAGS_MODULE_ADD(BODY)
	364	TAGS_MODULE_ADD(BLOCKQUOTE)
	365	TAGS_MODULE_ADD(DoNothing)
	366
	367	TAGS_MODULE_END(Layout)
	368
	369	#endif