haiku/src/servers/app/FontManager.cpp

/*
 * Copyright 2001-2005, Haiku.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *		DarkWyrm <bpmagic@columbus.rr.com>
 *		Axel Dörfler, axeld@pinc-software.de
 */

/**	Manages font families and styles */


#include <FontFamily.h>
#include <FontManager.h>
#include <ServerConfig.h>
#include <ServerFont.h>

#include <Autolock.h>
#include <Directory.h>
#include <Entry.h>
#include <File.h>
#include <FindDirectory.h>
#include <Message.h>
#include <NodeMonitor.h>
#include <Path.h>
#include <String.h>

#include <new>


//#define TRACE_WATCHING
#ifdef TRACE_WATCHING
#	define WTRACE(x) printf x
#else
#	define WTRACE(x) ;
#endif


// TODO: needs some more work for multi-user support

FT_Library gFreeTypeLibrary;
FontManager *gFontManager = NULL;

struct FontManager::font_directory {
	node_ref	directory;
	uid_t		user;
	gid_t		group;
	uint32		revision;
	BObjectList<FontStyle> styles;

	bool AlreadyScanned() const { return revision != 0; }
	FontStyle* FindStyle(const node_ref& nodeRef) const;
};

struct FontManager::font_mapping {
	BString		family;
	BString		style;
	entry_ref	ref;
};


FontStyle*
FontManager::font_directory::FindStyle(const node_ref& nodeRef) const
{
	for (int32 i = styles.CountItems(); i-- > 0;) {
		FontStyle* style = styles.ItemAt(i);

		if (nodeRef == style->NodeRef())
			return style;
	}

	return NULL;
}


static status_t
set_entry(node_ref& nodeRef, const char* name, BEntry& entry)
{
	entry_ref ref;
	ref.device = nodeRef.device;
	ref.directory = nodeRef.node;

	status_t status = ref.set_name(name);
	if (status != B_OK)
		return status;

	return entry.SetTo(&ref);
}


static int
compare_font_families(const FontFamily* a, const FontFamily* b)
{
	return strcmp(a->Name(), b->Name());
}


//	#pragma mark -


//! Does basic set up so that directories can be scanned
FontManager::FontManager()
	: BLooper("Font Manager"),
	fDirectories(10, true),
	fMappings(10, true),
	fFamilies(20),
	fScanned(false),
	fNextID(0)
{
	fInitStatus = FT_Init_FreeType(&gFreeTypeLibrary) == 0 ? B_OK : B_ERROR;

	if (fInitStatus == B_OK) {
		_AddSystemPaths();
		_LoadRecentFontMappings();

		fInitStatus = _SetDefaultFonts();
	}
}


//! Frees items allocated in the constructor and shuts down FreeType
FontManager::~FontManager()
{
	delete fDefaultPlainFont;
	delete fDefaultBoldFont;
	delete fDefaultFixedFont;

	// free families before we're done with FreeType

	for (int32 i = fFamilies.CountItems(); i-- > 0;) {
		delete fFamilies.ItemAt(i);
	}

	FT_Done_FreeType(gFreeTypeLibrary);
}


void
FontManager::MessageReceived(BMessage* message)
{
	switch (message->what) {
		case B_NODE_MONITOR:
		{
			// TODO: support removing fonts!

			int32 opcode;
			if (message->FindInt32("opcode", &opcode) != B_OK)
				return;

			switch (opcode) {
				case B_ENTRY_CREATED:
				{
					const char* name;
					node_ref nodeRef;
					if (message->FindInt32("device", &nodeRef.device) != B_OK
						|| message->FindInt64("directory", &nodeRef.node) != B_OK
						|| message->FindString("name", &name) != B_OK)
						break;

					// TODO: make this better (possible under Haiku)
					snooze(100000);
						// let the font be written completely before trying to open it

					BEntry entry;
					if (set_entry(nodeRef, name, entry) != B_OK)
						break;

					if (entry.IsDirectory()) {
						// a new directory to watch for us
						_AddPath(entry);
					} else {
						// a new font
						font_directory* directory = _FindDirectory(nodeRef);
						if (directory == NULL) {
							// unknown directory? how come?
							break;
						}

						_AddFont(*directory, entry);
					}
					break;
				}

				case B_ENTRY_MOVED:
				{
					// has the entry been moved into a monitored directory or has
					// it been removed from one?
					const char* name;
					node_ref nodeRef;
					uint64 fromNode;
					uint64 node;
					if (message->FindInt32("device", &nodeRef.device) != B_OK
						|| message->FindInt64("to directory", &nodeRef.node) != B_OK
						|| message->FindInt64("from directory", (int64 *)&fromNode) != B_OK
						|| message->FindInt64("node", (int64 *)&node) != B_OK
						|| message->FindString("name", &name) != B_OK)
						break;

					font_directory* directory = _FindDirectory(nodeRef);

					BEntry entry;
					if (set_entry(nodeRef, name, entry) != B_OK)
						break;

					if (directory != NULL) {
						// something has been added to our watched font directories
						if (entry.IsDirectory()) {
							// there is a new directory to watch for us
							_AddPath(entry);
						} else {
							// test, if the source directory is one of ours as well
							nodeRef.node = fromNode;
							font_directory* fromDirectory = _FindDirectory(nodeRef);
							if (fromDirectory != NULL) {
								// find style in source and move it to the target
								nodeRef.node = node;
								FontStyle* style = fromDirectory->FindStyle(nodeRef);
								if (style != NULL) {
									fromDirectory->styles.RemoveItem(style, false);
									directory->styles.AddItem(style);
								}
								WTRACE(("font moved"));
							} else {
								WTRACE(("font added: %s\n", name));
								_AddFont(*directory, entry);
							}
						}
					} else {
						// and entry has been removed from our font directories
						if (entry.IsDirectory()) {
							if (entry.GetNodeRef(&nodeRef) == B_OK
								&& (directory = _FindDirectory(nodeRef)) != NULL)
								_RemoveDirectory(directory);
						} else {
							// remove font style from directory
							_RemoveStyle(nodeRef.device, fromNode, node);
						}
					}
					break;
				}

				case B_ENTRY_REMOVED:
				{
					node_ref nodeRef;
					uint64 directoryNode;
					if (message->FindInt32("device", &nodeRef.device) != B_OK
						|| message->FindInt64("directory", (int64 *)&directoryNode) != B_OK
						|| message->FindInt64("node", &nodeRef.node) != B_OK)
						break;

					font_directory* directory = _FindDirectory(nodeRef);
					if (directory != NULL) {
						// the directory has been removed, so we remove it as well
						_RemoveDirectory(directory);
					} else {
						// remove font style from directory
						_RemoveStyle(nodeRef.device, directoryNode, nodeRef.node);
					}
					break;
				}
			}
			break;
		}
	}
}


void
FontManager::SaveRecentFontMappings()
{
}


bool
FontManager::_LoadRecentFontMappings()
{
	return false;
}


/*!
	\brief Removes the style from the font directory.

	It doesn't necessary delete the font style, if it's still
	in use, though.
*/
void
FontManager::_RemoveStyle(font_directory& directory, FontStyle* style)
{
	WTRACE(("font removed: %s\n", style->Name()));

	directory.styles.RemoveItem(style);
	directory.revision++;

	fStyleHashTable.RemoveItem(*style);

	style->Release();
}


void
FontManager::_RemoveStyle(dev_t device, uint64 directoryNode, uint64 node)
{
	// remove font style from directory
	node_ref nodeRef;
	nodeRef.device = device;
	nodeRef.node = directoryNode;

	font_directory* directory = _FindDirectory(nodeRef);
	if (directory != NULL) {
		// find style in directory and remove it
		nodeRef.node = node;
		FontStyle* style = directory->FindStyle(nodeRef);
		if (style != NULL)
			_RemoveStyle(*directory, style);
	}
}


FontStyle*
FontManager::_GetDefaultStyle(const char *familyName, const char *styleName,
	const char *fallbackFamily, const char *fallbackStyle,
	uint16 fallbackFace)
{
	// try to find a matching font

	FontStyle* style = GetStyle(familyName, styleName);
	if (style == NULL) {
		style = GetStyle(fallbackFamily, fallbackStyle);
		if (style == NULL) {
			style = FindStyleMatchingFace(fallbackFace);
			if (style == NULL && FamilyAt(0) != NULL)
				style = FamilyAt(0)->StyleAt(0);
		}
	}

	return style;
}


/*!
	\brief Sets the fonts that will be used when you create an empty
		ServerFont without specifying a style, as well as the default
		Desktop fonts if there are no settings available.
*/
status_t
FontManager::_SetDefaultFonts()
{
	FontStyle* style = _GetDefaultStyle(DEFAULT_PLAIN_FONT_FAMILY,
		DEFAULT_PLAIN_FONT_STYLE, FALLBACK_PLAIN_FONT_FAMILY,
		DEFAULT_PLAIN_FONT_STYLE,
		B_REGULAR_FACE);
	if (style == NULL)
		return B_ERROR;

	fDefaultPlainFont = new (nothrow) ServerFont(*style, DEFAULT_PLAIN_FONT_SIZE);
	if (fDefaultPlainFont == NULL)
		return B_NO_MEMORY;

	style = _GetDefaultStyle(DEFAULT_BOLD_FONT_FAMILY, DEFAULT_BOLD_FONT_STYLE,
		FALLBACK_BOLD_FONT_FAMILY, DEFAULT_BOLD_FONT_STYLE, B_BOLD_FACE);

	fDefaultBoldFont = new (nothrow) ServerFont(*style, DEFAULT_BOLD_FONT_SIZE);
	if (fDefaultBoldFont == NULL)
		return B_NO_MEMORY;

	style = _GetDefaultStyle(DEFAULT_FIXED_FONT_FAMILY, DEFAULT_FIXED_FONT_STYLE,
		FALLBACK_FIXED_FONT_FAMILY, DEFAULT_FIXED_FONT_STYLE, B_REGULAR_FACE);

	fDefaultFixedFont = new (nothrow) ServerFont(*style, DEFAULT_FIXED_FONT_SIZE);
	if (fDefaultFixedFont == NULL)
		return B_NO_MEMORY;

	fDefaultFixedFont->SetSpacing(B_FIXED_SPACING);
	return B_OK;
}


void
FontManager::_AddSystemPaths()
{
	BPath path;
	if (find_directory(B_BEOS_FONTS_DIRECTORY, &path, true) == B_OK)
		_AddPath(path.Path());

	// We don't scan these in test mode to help shave off some startup time
#if !TEST_MODE
	if (find_directory(B_COMMON_FONTS_DIRECTORY, &path, true) == B_OK)
		_AddPath(path.Path());
#endif
}


void
FontManager::_ScanFontsIfNecessary()
{
	if (!fScanned)
		_ScanFonts();
}


//! Scans all currently known font directories
void
FontManager::_ScanFonts()
{
	if (fScanned)
		return;

	for (int32 i = fDirectories.CountItems(); i-- > 0;) {
		font_directory* directory = fDirectories.ItemAt(i);

		if (directory->AlreadyScanned())
			continue;

		_ScanFontDirectory(*directory);
	}

	fScanned = true;
}


/*!
	\brief Adds the FontFamily/FontStyle that is represented by this path.
*/
status_t
FontManager::_AddFont(font_directory& directory, BEntry& entry)
{
	node_ref nodeRef;
	status_t status = entry.GetNodeRef(&nodeRef);
	if (status < B_OK)
		return status;

	BPath path;
	status = entry.GetPath(&path);
	if (status < B_OK)
		return status;

	FT_Face face;
	FT_Error error = FT_New_Face(gFreeTypeLibrary, path.Path(), 0, &face);
	if (error != 0)
		return B_ERROR;

    FontFamily *family = _FindFamily(face->family_name);
	if (family != NULL && family->HasStyle(face->style_name)) {
		// prevent adding the same style twice
		// (this indicates a problem with the installed fonts maybe?)
		FT_Done_Face(face);
		return B_OK;
	}

	if (family == NULL) {
		family = new (nothrow) FontFamily(face->family_name, fNextID++);
		if (family == NULL
			|| !fFamilies.BinaryInsert(family, compare_font_families)) {
			delete family;
			FT_Done_Face(face);
			return B_NO_MEMORY;
		}
	}

	WTRACE(("\tadd style: %s, %s\n", face->family_name, face->style_name));

	// the FontStyle takes over ownership of the FT_Face object
    FontStyle *style = new FontStyle(nodeRef, path.Path(), face);
	if (!family->AddStyle(style))
		delete style;

	directory.styles.AddItem(style);
	fStyleHashTable.AddItem(style);

	if (directory.AlreadyScanned())
		directory.revision++;

	return B_OK;
}


FontManager::font_directory*
FontManager::_FindDirectory(node_ref& nodeRef)
{
	for (int32 i = fDirectories.CountItems(); i-- > 0;) {
		font_directory* directory = fDirectories.ItemAt(i);

		if (directory->directory == nodeRef) 
			return directory;
	}

	return NULL;
}


void
FontManager::_RemoveDirectory(font_directory* directory)
{
	WTRACE(("FontManager: Remove directory (%Ld)!\n", directory->directory.node));

	fDirectories.RemoveItem(directory, false);

	// TODO: remove styles from this directory!

	watch_node(&directory->directory, B_STOP_WATCHING, this);
	delete directory;
}


status_t
FontManager::_AddPath(const char* path)
{
	BEntry entry;
	status_t status = entry.SetTo(path);
	if (status != B_OK)
		return status;

	return _AddPath(entry);
}


status_t
FontManager::_AddPath(BEntry& entry, font_directory** _newDirectory)
{
	node_ref nodeRef;
	status_t status = entry.GetNodeRef(&nodeRef);
	if (status != B_OK)
		return status;

	// check if we are already know this directory

	font_directory* directory = _FindDirectory(nodeRef);
	if (directory != NULL) {
		*_newDirectory = directory;
		return B_OK;
	}

	// it's a new one, so let's add it

	directory = new (nothrow) font_directory;
	if (directory == NULL)
		return B_NO_MEMORY;

	struct stat stat;
	status = entry.GetStat(&stat);
	if (status != B_OK) {
		delete directory;
		return status;
	}

	directory->directory = nodeRef;
	directory->user = stat.st_uid;
	directory->group = stat.st_gid;
	directory->revision = 0;

	status = watch_node(&nodeRef, B_WATCH_DIRECTORY, this);
	if (status != B_OK) {
		// we cannot watch this directory - while this is unfortunate,
		// it's not a critical error
		printf("could not watch directory %ld:%Ld\n", nodeRef.device, nodeRef.node);
			// TODO: should go into syslog()
	} else {
		BPath path(&entry);
		WTRACE(("FontManager: now watching: %s\n", path.Path()));
	}

	fDirectories.AddItem(directory);

	if (_newDirectory)
		*_newDirectory = directory;

	fScanned = false;
	return B_OK;
}


/*!
	\brief Scan a folder for all valid fonts
	\param directoryPath Path of the folder to scan.
*/
status_t
FontManager::_ScanFontDirectory(font_directory& fontDirectory)
{
	// This bad boy does all the real work. It loads each entry in the
	// directory. If a valid font file, it adds both the family and the style.

	BDirectory directory;
	status_t status = directory.SetTo(&fontDirectory.directory);
	if (status != B_OK)
		return status;

	BEntry entry;
	while (directory.GetNextEntry(&entry) == B_OK) {
		if (entry.IsDirectory()) {
			// scan this directory recursively
			font_directory* newDirectory;
			if (_AddPath(entry, &newDirectory) == B_OK && newDirectory != NULL)
				_ScanFontDirectory(*newDirectory);

			continue;
		}

// TODO: Commenting this out makes my "Unicode glyph lookup"
// work with our default fonts. The real fix is to select the
// Unicode char map (if supported), and/or adjust the
// utf8 -> glyph-index mapping everywhere to handle other
// char maps. We could also ignore fonts that don't support
// the Unicode lookup as a temporary "solution".
#if 0
		FT_CharMap charmap = _GetSupportedCharmap(face);
		if (!charmap) {
		    FT_Done_Face(face);
		    continue;
    	}

		face->charmap = charmap;
#endif

		_AddFont(fontDirectory, entry);
			// takes over ownership of the FT_Face object
	}

	fontDirectory.revision = 1;
	return B_OK;
}


/*!
	\brief Finds and returns the first valid charmap in a font
	
	\param face Font handle obtained from FT_Load_Face()
	\return An FT_CharMap or NULL if unsuccessful
*/
FT_CharMap
FontManager::_GetSupportedCharmap(const FT_Face& face)
{
	for (int32 i = 0; i < face->num_charmaps; i++) {
		FT_CharMap charmap = face->charmaps[i];

		switch (charmap->platform_id) {
			case 3:
				// if Windows Symbol or Windows Unicode
				if (charmap->encoding_id == 0 || charmap->encoding_id == 1)
					return charmap;
				break;

			case 1:
				// if Apple Unicode
				if (charmap->encoding_id == 0)
					return charmap;
				break;

			case 0:
				// if Apple Roman
				if (charmap->encoding_id == 0)
					return charmap;
				break;

			default:
				break;
		}
	}

	return NULL;
}


int32
FontManager::CheckRevision(uid_t user)
{
	BAutolock locker(this);
	int32 revision = 0;

	_ScanFontsIfNecessary();

	for (int32 i = 0; i < fDirectories.CountItems(); i++) {
		font_directory* directory = fDirectories.ItemAt(i);

		// TODO: for now, add all directories
		revision += directory->revision;
	}

	return revision;
}


/*!
	\brief Counts the number of font families available
	\return The number of unique font families currently available
*/
int32
FontManager::CountFamilies()
{
	_ScanFontsIfNecessary();

	return fFamilies.CountItems();
}


/*!
	\brief Counts the number of styles available in a font family
	\param family Name of the font family to scan
	\return The number of font styles currently available for the font family
*/
int32
FontManager::CountStyles(const char *familyName)
{
	_ScanFontsIfNecessary();

	FontFamily *family = GetFamily(familyName);
	if (family)
		return family->CountStyles();

	return 0;
}


FontFamily*
FontManager::FamilyAt(int32 index) const
{
	return fFamilies.ItemAt(index);
}


FontFamily*
FontManager::_FindFamily(const char* name) const
{
	if (name == NULL)
		return NULL;

	FontFamily family(name, 0);
	return const_cast<FontFamily*>(fFamilies.BinarySearch(family,
		compare_font_families));
}


/*!
	\brief Locates a FontFamily object by name
	\param name The family to find
	\return Pointer to the specified family or NULL if not found.
*/
FontFamily*
FontManager::GetFamily(const char* name)
{
	if (name == NULL)
		return NULL;

	FontFamily* family = _FindFamily(name);
	if (family != NULL)
		return family;

	if (fScanned)
		return NULL;

	// try again
	family = _FindFamily(name);
	if (family != NULL)
		return family;

	// try font mappings before failing
	for (int32 i = 0; i < fMappings.CountItems(); i++) {
		font_mapping* mapping = fMappings.ItemAt(i);

		if (mapping->family == name) {
			BEntry entry(&mapping->ref);
			if (entry.InitCheck() != B_OK)
				continue;

			// find parent directory
			
			node_ref nodeRef;
			nodeRef.device = mapping->ref.device;
			nodeRef.node = mapping->ref.directory;
			font_directory* directory = _FindDirectory(nodeRef);
			if (directory == NULL) {
				// unknown directory, maybe this is a user font
				continue;
			}

			if (_AddFont(*directory, entry) == B_OK)
				return _FindFamily(name);
		}
	}

	_ScanFonts();
	return _FindFamily(name);
}


FontFamily*
FontManager::GetFamily(uint16 familyID) const
{
	FontKey key(familyID, 0);
	FontStyle* style = (FontStyle*)fStyleHashTable.GetValue(key);
	if (style != NULL)
		return style->Family();

	return NULL;
}


FontStyle*
FontManager::GetStyleByIndex(const char* familyName, int32 index)
{
	FontFamily* family = GetFamily(familyName);
	if (family != NULL)
		return family->StyleAt(index);

	return NULL;
}


/*!
	\brief Retrieves the FontStyle object that comes closest to the one specified

	\param family The font's family or NULL in which case \a familyID is used
	\param style The font's style or NULL in which case \a styleID is used
	\param familyID will only be used if \a family is NULL (or empty)
	\param styleID will only be used if \a style is NULL (or empty)
	\param face is used to specify the style if both \a style is NULL or empty
		and styleID is 0xffff.

	\return The FontStyle having those attributes or NULL if not available
*/
FontStyle*
FontManager::GetStyle(const char* familyName, const char* styleName, uint16 familyID,
	uint16 styleID, uint16 face)
{
	FontFamily* family;

	// find family

	if (familyName != NULL && familyName[0])
		family = GetFamily(familyName);
	else
		family = GetFamily(familyID);

	if (family == NULL)
		return NULL;

	// find style

	if (styleName != NULL && styleName[0])
		return family->GetStyle(styleName);

	if (styleID != 0xffff)
		return family->GetStyleByID(styleID);

	// try to get from face
	return family->GetStyleMatchingFace(face);
}


/*!
	\brief Retrieves the FontStyle object
	\param family ID for the font's family
	\param style ID of the font's style
	\return The FontStyle having those attributes or NULL if not available
*/
FontStyle*
FontManager::GetStyle(uint16 familyID, uint16 styleID) const
{
	FontKey key(familyID, styleID);
	return (FontStyle*)fStyleHashTable.GetValue(key);
}


/*!
	\brief If you don't find your preferred font style, but are anxious
		to have one fitting your needs, you may want to use this method.
*/
FontStyle*
FontManager::FindStyleMatchingFace(uint16 face) const
{
	int32 count = fFamilies.CountItems();

	for (int32 i = 0; i < count; i++) {
		FontFamily* family = fFamilies.ItemAt(i);
		FontStyle* style = family->GetStyleMatchingFace(face);
		if (style != NULL)
			return style;
	}

	return NULL;
}


/*!
	\brief This call is used by the FontStyle class - and the FontStyle class
		only - to remove itself from the font manager.
	At this point, the style is already no longer available to the user.
*/
void
FontManager::RemoveStyle(FontStyle* style)
{
	FontFamily* family = style->Family();
	if (family == NULL)
		debugger("family is NULL!");

	FontStyle* check = GetStyle(family->ID(), style->ID());
	if (check != NULL)
		debugger("style removed but still available!");

	if (family->RemoveStyle(style)
		&& family->CountStyles() == 0)
		fFamilies.RemoveItem(family);
}


const ServerFont*
FontManager::DefaultPlainFont() const
{
	return fDefaultPlainFont;
}


const ServerFont*
FontManager::DefaultBoldFont() const
{
	return fDefaultBoldFont;
}


const ServerFont*
FontManager::DefaultFixedFont() const
{
	return fDefaultFixedFont;
}


void
FontManager::AttachUser(uid_t userID)
{
	BAutolock locker(this);

/*
	BPath path;
	status_t status = find_directory(B_USER_FONTS_DIRECTORY, &path);
	if (status != B_OK)
		return status;

	_AddPath(path.Path());
*/
}


void
FontManager::DetachUser(uid_t userID)
{
	BAutolock locker(this);
}