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// Copyright 2014 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com

#ifndef PUBLIC_FPDF_SYSFONTINFO_H_
#define PUBLIC_FPDF_SYSFONTINFO_H_

#include "fpdfview.h"

/* Character sets for the font */
#define FXFONT_ANSI_CHARSET     0
#define FXFONT_DEFAULT_CHARSET  1
#define FXFONT_SYMBOL_CHARSET   2
#define FXFONT_SHIFTJIS_CHARSET 128
#define FXFONT_HANGEUL_CHARSET  129
#define FXFONT_GB2312_CHARSET   134
#define FXFONT_CHINESEBIG5_CHARSET  136

/* Font pitch and family flags */
#define FXFONT_FF_FIXEDPITCH    1
#define FXFONT_FF_ROMAN         (1<<4)
#define FXFONT_FF_SCRIPT        (4<<4)

/* Typical weight values */
#define FXFONT_FW_NORMAL        400
#define FXFONT_FW_BOLD          700

// Exported Functions
#ifdef __cplusplus
extern "C" {
#endif

/**
 * Interface: FPDF_SYSFONTINFO
 *          Interface for getting system font information and font mapping
 */
typedef struct _FPDF_SYSFONTINFO {
    /**
     * Version number of the interface. Currently must be 1.
     **/
    int version;

    /**
     * Method: Release
     *          Give implementation a chance to release any data after the interface is no longer used
     * Interface Version:
     *          1
     * Implementation Required:
     *          No
     * Comments:
     *          Called by Foxit SDK during the final cleanup process.
     * Parameters:
     *          pThis       -   Pointer to the interface structure itself
     * Return Value:
     *          None
     */
    void (*Release)(struct _FPDF_SYSFONTINFO* pThis);

    /**
     * Method: EnumFonts
     *          Enumerate all fonts installed on the system
     * Interface Version:
     *          1
     * Implementation Required:
     *          No
     * Comments:
     *          Implementation should call FPDF_AddIntalledFont() function for each font found.
     *          Only TrueType/OpenType and Type1 fonts are accepted by Foxit SDK.
     * Parameters:
     *          pThis       -   Pointer to the interface structure itself
     *          pMapper     -   An opaque pointer to internal font mapper, used when calling FPDF_AddInstalledFont
     * Return Value:
     *          None
     */
    void (*EnumFonts)(struct _FPDF_SYSFONTINFO* pThis, void* pMapper);

    /**
     * Method: MapFont
     *          Use the system font mapper to get a font handle from requested parameters
     * Interface Version:
     *          1
     * Implementation Required:
     *          Yes only if GetFont method is not implemented.
     * Comments:
     *          If the system supports native font mapper (like Windows), implementation can implement this method to get a font handle.
     *          Otherwise, Foxit SDK will do the mapping and then call GetFont method.
     *          Only TrueType/OpenType and Type1 fonts are accepted by Foxit SDK.
     * Parameters:
     *          pThis       -   Pointer to the interface structure itself
     *          weight      -   Weight of the requested font. 400 is normal and 700 is bold.
     *          bItalic     -   Italic option of the requested font, TRUE or FALSE.
     *          charset     -   Character set identifier for the requested font. See above defined constants.
     *          pitch_family -  A combination of flags. See above defined constants.
     *          face        -   Typeface name. Currently use system local encoding only.
     *          bExact      -   Pointer to an boolean value receiving the indicator whether mapper found the exact match.
     *                          If mapper is not sure whether it's exact match, ignore this paramter.
     * Return Value:
     *          An opaque pointer for font handle, or NULL if system mapping is not supported.
     **/
    void* (*MapFont)(struct _FPDF_SYSFONTINFO* pThis, int weight, int bItalic, int charset, int pitch_family,
                        const char* face, int* bExact);

    /**
     * Method: GetFont
     *          Get a handle to a particular font by its internal ID
     * Interface Version:
     *          1
     * Implementation Required:
     *          Yes only if MapFont method is not implemented.
     * Comments:
     *          If the system mapping not supported, Foxit SDK will do the font mapping and use this method to get a font handle.
     * Parameters:
     *          pThis       -   Pointer to the interface structure itself
     *          face        -   Typeface name. Currently use system local encoding only.
     * Return Value:
     *          An opaque pointer for font handle.
     **/
    void* (*GetFont)(struct _FPDF_SYSFONTINFO* pThis, const char* face);

    /**
     * Method: GetFontData
     *          Get font data from a font
     * Interface Version:
     *          1
     * Implementation Required:
     *          Yes
     * Comments:
     *          Can read either full font file, or a particular TrueType/OpenType table
     * Parameters:
     *          pThis       -   Pointer to the interface structure itself
     *          hFont       -   Font handle returned by MapFont or GetFont method
     *          table       -   TrueType/OpenType table identifier (refer to TrueType specification).
     *                          0 for the whole font file.
     *          buffer      -   The buffer receiving the font data. Can be NULL if not provided
     *          buf_size    -   Buffer size, can be zero if not provided
     * Return Value:
     *          Number of bytes needed, if buffer not provided or not large enough,
     *          or number of bytes written into buffer otherwise.
     **/
    unsigned long (*GetFontData)(struct _FPDF_SYSFONTINFO* pThis, void* hFont,
            unsigned int table, unsigned char* buffer, unsigned long buf_size);

    /**
     * Method: GetFaceName
     *          Get face name from a font handle
     * Interface Version:
     *          1
     * Implementation Required:
     *          No
     * Parameters:
     *          pThis       -   Pointer to the interface structure itself
     *          hFont       -   Font handle returned by MapFont or GetFont method
     *          buffer      -   The buffer receiving the face name. Can be NULL if not provided
     *          buf_size    -   Buffer size, can be zero if not provided
     * Return Value:
     *          Number of bytes needed, if buffer not provided or not large enough,
     *          or number of bytes written into buffer otherwise.
     **/
    unsigned long (*GetFaceName)(struct _FPDF_SYSFONTINFO* pThis, void* hFont, char* buffer, unsigned long buf_size);

    /**
     * Method: GetFontCharset
     *          Get character set information for a font handle
     * Interface Version:
     *          1
     * Implementation Required:
     *          No
     * Parameters:
     *          pThis       -   Pointer to the interface structure itself
     *          hFont       -   Font handle returned by MapFont or GetFont method
     * Return Value:
     *          Character set identifier. See defined constants above.
     **/
    int (*GetFontCharset)(struct _FPDF_SYSFONTINFO* pThis, void* hFont);

    /**
     * Method: DeleteFont
     *          Delete a font handle
     * Interface Version:
     *          1
     * Implementation Required:
     *          Yes
     * Parameters:
     *          pThis       -   Pointer to the interface structure itself
     *          hFont       -   Font handle returned by MapFont or GetFont method
     * Return Value:
     *          None
     **/
    void (*DeleteFont)(struct _FPDF_SYSFONTINFO* pThis, void* hFont);
} FPDF_SYSFONTINFO;

/**
 * Struct: FPDF_CharsetFontMap
 *    Provides the name of a font to use for a given charset value.
 **/
typedef struct FPDF_CharsetFontMap_
{
    int charset;  // Character Set Enum value, see FXFONT_*_CHARSET above.
    const char* fontname;  // Name of default font to use with that charset.
} FPDF_CharsetFontMap;

/**
 * Function: FPDF_GetDefaultTTFMap
 *    Returns a pointer to the default character set to TT Font name map. The
 *    map is an array of FPDF_CharsetFontMap structs, with its end indicated
 *    by a { -1, NULL } entry.
 * Parameters:
 *     None.
 * Return Value:
 *     Pointer to the Charset Font Map.
 **/
DLLEXPORT const FPDF_CharsetFontMap* STDCALL FPDF_GetDefaultTTFMap();

/**
 * Function: FPDF_AddInstalledFont
 *          Add a system font to the list in Foxit SDK.
 * Comments:
 *          This function is only called during the system font list building process.
 * Parameters:
 *          mapper          -   Opaque pointer to Foxit font mapper
 *          face            -   The font face name
 *          charset         -   Font character set. See above defined constants.
 * Return Value:
 *          None.
 **/
DLLEXPORT void STDCALL FPDF_AddInstalledFont(void* mapper, const char* face, int charset);

/**
 * Function: FPDF_SetSystemFontInfo
 *          Set the system font info interface into Foxit SDK
 * Comments:
 *          Platform support implementation should implement required methods of FFDF_SYSFONTINFO interface,
 *          then call this function during SDK initialization process.
 * Parameters:
 *          pFontInfo       -   Pointer to a FPDF_SYSFONTINFO structure
 * Return Value:
 *          None
 **/
DLLEXPORT void STDCALL FPDF_SetSystemFontInfo(FPDF_SYSFONTINFO* pFontInfo);

/**
 * Function: FPDF_GetDefaultSystemFontInfo
 *          Get default system font info interface for current platform
 * Comments:
 *          For some platforms Foxit SDK implement a default version of system font info interface.
 *          The default implementation can be used in FPDF_SetSystemFontInfo function.
 * Parameters:
 *          None
 * Return Value:
 *          Pointer to a FPDF_SYSFONTINFO structure describing the default interface.
 *          Or NULL if the platform doesn't have a default interface.
 *          Application should call FPDF_FreeMemory to free the returned pointer.
 **/
DLLEXPORT FPDF_SYSFONTINFO* STDCALL FPDF_GetDefaultSystemFontInfo();

#ifdef __cplusplus
}
#endif

#endif  // PUBLIC_FPDF_SYSFONTINFO_H_