/* Copyright (C) 2007-2008 The Android Open Source Project
**
** This software is licensed under the terms of the GNU General Public
** License version 2, as published by the Free Software Foundation, and
** may be copied, distributed, and modified under those terms.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
** GNU General Public License for more details.
*/
#ifndef _android_gsm_h
#define _android_gsm_h

/** USEFUL TYPES
 **/

typedef unsigned char  byte_t;
typedef byte_t*        bytes_t;
typedef const byte_t*  cbytes_t;

/** BCD
 **/

/* convert a 8-bit value into the corresponding nibble-bcd byte */
extern byte_t   gsm_int_to_bcdi( int  value );

/* convert a nibble-bcd byte into an int, invalid nibbles are silently converted to 0 */
extern int      gsm_int_from_bcdi( byte_t  value );

/** HEX
 **/

/* try to convert a hex string into a byte string, assumes 'dst' is properly sized, and hexlen is even.
 * returns the number of bytes on exit, or -1 in case of badly formatted data */
extern int      gsm_hex_to_bytes  ( cbytes_t  hex, int  hexlen, bytes_t  dst );

/* convert a hex string into a byte string, assumes 'dst' is properly sized, and hexlen is even.
 * no checks are performed */
extern void     gsm_hex_to_bytes0 ( cbytes_t  hex, int  hexlen, bytes_t  dst );

/* convert a byte string into a hex string, assumes 'hex' is properly sized */
extern void     gsm_hex_from_bytes( char*  hex, cbytes_t  src, int  srclen );

/* convert a hexchar to an int, returns -1 on error */
extern int      gsm_hexchar_to_int( char  c );

/* convert a hexchar to an int, returns 0 on error */
extern int      gsm_hexchar_to_int0( char  c );

/* convert a 2-char hex value into an int, returns -1 on error */
extern int      gsm_hex2_to_byte( const char*  hex );

/* convert a 2-char hex value into an int, returns 0 on error */
extern int      gsm_hex2_to_byte0( const char*  hex );

/* convert a 4-char hex value into an int, returns -1 on error */
extern int      gsm_hex4_to_short( const char*  hex );

/* convert a 4-char hex value into an int, returns 0 on error */
extern int      gsm_hex4_to_short0( const char*  hex );

/* write a byte to a 2-byte hex string */
extern void     gsm_hex_from_byte( char*  hex, int  val );

extern void     gsm_hex_from_short( char*  hex, int  val );

/** UTF-8 and GSM Alphabet
 **/

/* check that a given utf8 string is well-formed, returns 1 on success, 0 otherwise */
extern int      utf8_check( cbytes_t  utf8, int  utf8len );

/* check that all characters in a given utf8 string can be encoded into the GSM alphabet.
   returns 1 if TRUE, 0 otherwise */
extern int      utf8_check_gsm7( cbytes_t  utf8, int  utf8len );

/* try to skip enough utf8 characters to generate gsm7len GSM septets */
extern cbytes_t utf8_skip_gsm7( cbytes_t  utf8, cbytes_t  utf8end, int  gsm7len );

/* convert a utf-8 string into a GSM septet string, assumes 'dst' is NULL or is properly sized,
   and that all characters are representable. 'offset' is the starting bit offset in 'dst'.
   non-representable characters are replaced by spaces.
   returns the number of septets, */
extern int      utf8_to_gsm7( cbytes_t  utf8, int  utf8len, bytes_t  dst, int  offset );

/* convert a utf8 string into an array of 8-bit unpacked GSM septets,
 * assumes 'dst' is NULL or is properly sized, returns the number of GSM bytes */
extern int      utf8_to_gsm8( cbytes_t  utf8, int  utf8len, bytes_t  dst );

/* convert a GSM septets string into a utf-8 byte string. assumes that 'utf8' is NULL or properly
   sized. 'offset' is the starting bit offset in 'src', 'count' is the number of input septets.
   return the number of utf8 bytes. */
extern int      utf8_from_gsm7( cbytes_t  src, int  offset, int  count, bytes_t  utf8 );

/* convert an unpacked 8-bit GSM septets string into a utf-8 byte string. assumes that 'utf8'
   is NULL or properly sized. 'count' is the number of input bytes.
   returns the number of utf8 bytes */
extern int      utf8_from_gsm8( cbytes_t  src, int  count, bytes_t  utf8 );


/** UCS-2 and GSM Alphabet
 **
 ** Note that here, 'ucs2' really refers to non-aligned UCS2-BE, as used by the GSM standard
 **/

/* check that all characters in a given ucs2 string can be encoded into the GSM alphabet.
   returns 1 if TRUE, 0 otherwise */
extern int      ucs2_check_gsm7( cbytes_t  ucs2, int  ucs2len );

/* convert a ucs2 string into a GSM septet string, assumes 'dst' is NULL or properly sized,
   'offset' is the starting bit offset in 'dst'. non-representable characters are replaced
   by spaces. returns the number of septets */
extern int      ucs2_to_gsm7( cbytes_t  ucs2, int  ucs2len, bytes_t  dst, int  offset );

/* convert a ucs2 string into a GSM septet string, assumes 'dst' is NULL or properly sized,
   non-representable characters are replaced by spaces. returns the number of bytes */
extern int      ucs2_to_gsm8( cbytes_t  ucs2, int  ucs2len, bytes_t  dst );

/* convert a GSM septets string into a ucs2 string. assumes that 'ucs2' is NULL or
   properly sized. 'offset' is the starting bit offset in 'src', 'count' is the number
   of input septets. return the number of ucs2 characters (not bytes) */
extern int      ucs2_from_gsm7( bytes_t   ucs2, cbytes_t  src, int  offset, int  count );

/* convert an 8-bit unpacked GSM septets string into a ucs2 string. assumes that 'ucs2'
   is NULL or properly sized. 'count' is the number of input septets. return the number
   of ucs2 characters (not bytes) */
extern int      ucs2_from_gsm8( bytes_t   ucs2, cbytes_t  src, int  count );


/** UCS2 to/from UTF8
 **/

/* convert a ucs2 string into a utf8 byte string, assumes 'utf8' NULL or properly sized.
   returns the number of utf8 bytes*/
extern int      ucs2_to_utf8( cbytes_t  ucs2, int  ucs2len, bytes_t  utf8 );

/* convert a utf8 byte string into a ucs2 string, assumes 'ucs2' NULL or properly sized.
   returns the number of ucs2 chars */
extern int      utf8_to_ucs2( cbytes_t  utf8, int  utf8len, bytes_t  ucs2 );

/* try to skip a given number of characters in a utf-8 byte string, return new position */
extern cbytes_t  utf8_skip( cbytes_t   utf8, cbytes_t   utf8end, int  count);

/** Dial Numbers: TON byte + 'count' bcd numbers
 **/

/* convert a bcd-coded GSM dial number into an ASCII string (not zero-terminated)
   assumes 'dst' is NULL or properly sized, returns 0 in case of success, -1 in case of error.
   'num_digits' is the number of digits, not input bytes. a trailing 0xf0 is ignored automatically
   return the number of ASCII chars */
extern int  gsm_bcdnum_to_ascii  ( cbytes_t  bcd, int  num_digits, bytes_t  dst );

/* convert an ASCII dial-number into a bcd-coded string, returns the number of 4-bit nibbles written, */
extern int  gsm_bcdnum_from_ascii( cbytes_t  ascii, int  asciilen, bytes_t  dst );

/** ADN: Abbreviated Dialing Numbers
 **/
#define  SIM_ADN_MAX_ALPHA        20  /* maximum number of characters in ADN alpha tag */
#define  SIM_ADN_MAX_NUMBER       20  /* maximum digits in ADN number */

typedef struct {
    byte_t  alpha [ SIM_ADN_MAX_ALPHA*3+1 ];  /* alpha tag in zero-terminated utf-8      */
    char    number[ SIM_ADN_MAX_NUMBER+1 ];   /* dialing number in zero-terminated ASCII */
}
SimAdnRec, *SimAdn;

typedef struct {
    SimAdnRec       adn;
    byte_t          ext_record;  /* 0 or 0xFF means no extension */
}
SimAdnRecordRec, *SimAdnRecord;

extern int  sim_adn_record_from_bytes( SimAdnRecord  rec, cbytes_t  data, int  datalen );
extern int  sim_adn_record_to_bytes  ( SimAdnRecord  rec, bytes_t   data, int  datalen );

/** ROPES
 **/

typedef struct {
    bytes_t         data;
    int             max;
    int             pos;
    int             error;
    unsigned char   data0[16];
} GsmRopeRec, *GsmRope;

extern void      gsm_rope_init( GsmRope  rope );
extern void      gsm_rope_init_alloc( GsmRope  rope, int  alloc );
extern int       gsm_rope_done( GsmRope  rope );
extern bytes_t   gsm_rope_done_acquire( GsmRope  rope, int  *psize );
extern void      gsm_rope_add_c( GsmRope  rope, char  c );
extern void      gsm_rope_add( GsmRope  rope, const void*  str, int  len );
extern void*     gsm_rope_reserve( GsmRope  rope, int  len );

#endif /* _android_gsm_h */