/*

 * Copyright © 2018 Adobe Inc.

 *

 *  This is part of HarfBuzz, a text shaping library.

 *

 * Permission is hereby granted, without written agreement and without

 * license or royalty fees, to use, copy, modify, and distribute this

 * software and its documentation for any purpose, provided that the

 * above copyright notice and the following two paragraphs appear in

 * all copies of this software.

 *

 * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR

 * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES

 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN

 * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH

 * DAMAGE.

 *

 * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,

 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

 * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS

 * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO

 * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

 *

 * Adobe Author(s): Michiharu Ariza

 */

#ifndef HB_CFF_INTERP_COMMON_HH

#define HB_CFF_INTERP_COMMON_HH

namespace CFF {

using namespace OT;

typedef unsigned int op_code_t;

/* === Dict operators === */

/* One byte operators (0-31) */

#define OpCode_version            0 /* CFF Top */

#define OpCode_Notice             1 /* CFF Top */

#define OpCode_FullName           2 /* CFF Top */

#define OpCode_FamilyName         3 /* CFF Top */

#define OpCode_Weight             4 /* CFF Top */

#define OpCode_FontBBox           5 /* CFF Top */

#define OpCode_BlueValues         6 /* CFF Private, CFF2 Private */

#define OpCode_OtherBlues         7 /* CFF Private, CFF2 Private */

#define OpCode_FamilyBlues        8 /* CFF Private, CFF2 Private */

#define OpCode_FamilyOtherBlues   9 /* CFF Private, CFF2 Private */

#define OpCode_StdHW             10 /* CFF Private, CFF2 Private */

#define OpCode_StdVW             11 /* CFF Private, CFF2 Private */

#define OpCode_escape            12 /* All. Shared with CS */

#define OpCode_UniqueID          13 /* CFF Top */

#define OpCode_XUID              14 /* CFF Top */

#define OpCode_charset           15 /* CFF Top (0) */

#define OpCode_Encoding          16 /* CFF Top (0) */

#define OpCode_CharStrings       17 /* CFF Top, CFF2 Top */

#define OpCode_Private           18 /* CFF Top, CFF2 FD */

#define OpCode_Subrs             19 /* CFF Private, CFF2 Private */

#define OpCode_defaultWidthX     20 /* CFF Private (0) */

#define OpCode_nominalWidthX     21 /* CFF Private (0) */

#define OpCode_vsindexdict       22 /* CFF2 Private/CS */

#define OpCode_blenddict         23 /* CFF2 Private/CS */

#define OpCode_vstore            24 /* CFF2 Top */

#define OpCode_reserved25        25

#define OpCode_reserved26        26

#define OpCode_reserved27        27

/* Numbers */

#define OpCode_shortint          28 /* 16-bit integer, All */

#define OpCode_longintdict       29 /* 32-bit integer, All */

#define OpCode_BCD               30 /* Real number, CFF2 Top/FD */

#define OpCode_reserved31        31

/* 1-byte integers */

#define OpCode_OneByteIntFirst   32 /* All. beginning of the range of first byte ints */

#define OpCode_OneByteIntLast   246 /* All. ending of the range of first byte int */

/* 2-byte integers */

#define OpCode_TwoBytePosInt0   247 /* All. first byte of two byte positive int (+108 to +1131) */

#define OpCode_TwoBytePosInt1   248

#define OpCode_TwoBytePosInt2   249

#define OpCode_TwoBytePosInt3   250

#define OpCode_TwoByteNegInt0   251 /* All. first byte of two byte negative int (-1131 to -108) */

#define OpCode_TwoByteNegInt1   252

#define OpCode_TwoByteNegInt2   253

#define OpCode_TwoByteNegInt3   254

/* Two byte escape operators 12, (0-41) */

#define OpCode_ESC_Base         256

#define Make_OpCode_ESC(byte2)  ((op_code_t)(OpCode_ESC_Base + (byte2)))

inline op_code_t Unmake_OpCode_ESC (op_code_t op)  { return (op_code_t)(op - OpCode_ESC_Base); }

inline bool Is_OpCode_ESC (op_code_t op) { return op >= OpCode_ESC_Base; }

inline unsigned int OpCode_Size (op_code_t op) { return Is_OpCode_ESC (op) ? 2: 1; }

#define OpCode_Copyright        Make_OpCode_ESC(0) /* CFF Top */

#define OpCode_isFixedPitch     Make_OpCode_ESC(1) /* CFF Top (false) */

#define OpCode_ItalicAngle      Make_OpCode_ESC(2) /* CFF Top (0) */

#define OpCode_UnderlinePosition Make_OpCode_ESC(3) /* CFF Top (-100) */

#define OpCode_UnderlineThickness Make_OpCode_ESC(4) /* CFF Top (50) */

#define OpCode_PaintType        Make_OpCode_ESC(5) /* CFF Top (0) */

#define OpCode_CharstringType   Make_OpCode_ESC(6) /* CFF Top (2) */

#define OpCode_FontMatrix       Make_OpCode_ESC(7) /* CFF Top, CFF2 Top (.001 0 0 .001 0 0)*/

#define OpCode_StrokeWidth      Make_OpCode_ESC(8) /* CFF Top (0) */

#define OpCode_BlueScale        Make_OpCode_ESC(9) /* CFF Private, CFF2 Private (0.039625) */

#define OpCode_BlueShift        Make_OpCode_ESC(10) /* CFF Private, CFF2 Private (7) */

#define OpCode_BlueFuzz         Make_OpCode_ESC(11) /* CFF Private, CFF2 Private (1) */

#define OpCode_StemSnapH        Make_OpCode_ESC(12) /* CFF Private, CFF2 Private */

#define OpCode_StemSnapV        Make_OpCode_ESC(13) /* CFF Private, CFF2 Private */

#define OpCode_ForceBold        Make_OpCode_ESC(14) /* CFF Private (false) */

#define OpCode_reservedESC15    Make_OpCode_ESC(15)

#define OpCode_reservedESC16    Make_OpCode_ESC(16)

#define OpCode_LanguageGroup    Make_OpCode_ESC(17) /* CFF Private, CFF2 Private (0) */

#define OpCode_ExpansionFactor  Make_OpCode_ESC(18) /* CFF Private, CFF2 Private (0.06) */

#define OpCode_initialRandomSeed Make_OpCode_ESC(19) /* CFF Private (0) */

#define OpCode_SyntheticBase    Make_OpCode_ESC(20) /* CFF Top */

#define OpCode_PostScript       Make_OpCode_ESC(21) /* CFF Top */

#define OpCode_BaseFontName     Make_OpCode_ESC(22) /* CFF Top */

#define OpCode_BaseFontBlend    Make_OpCode_ESC(23) /* CFF Top */

#define OpCode_reservedESC24    Make_OpCode_ESC(24)

#define OpCode_reservedESC25    Make_OpCode_ESC(25)

#define OpCode_reservedESC26    Make_OpCode_ESC(26)

#define OpCode_reservedESC27    Make_OpCode_ESC(27)

#define OpCode_reservedESC28    Make_OpCode_ESC(28)

#define OpCode_reservedESC29    Make_OpCode_ESC(29)

#define OpCode_ROS              Make_OpCode_ESC(30) /* CFF Top_CID */

#define OpCode_CIDFontVersion   Make_OpCode_ESC(31) /* CFF Top_CID (0) */

#define OpCode_CIDFontRevision  Make_OpCode_ESC(32) /* CFF Top_CID (0) */

#define OpCode_CIDFontType      Make_OpCode_ESC(33) /* CFF Top_CID (0) */

#define OpCode_CIDCount         Make_OpCode_ESC(34) /* CFF Top_CID (8720) */

#define OpCode_UIDBase          Make_OpCode_ESC(35) /* CFF Top_CID */

#define OpCode_FDArray          Make_OpCode_ESC(36) /* CFF Top_CID, CFF2 Top */

#define OpCode_FDSelect         Make_OpCode_ESC(37) /* CFF Top_CID, CFF2 Top */

#define OpCode_FontName         Make_OpCode_ESC(38) /* CFF Top_CID */

/* === CharString operators === */

#define OpCode_hstem              1 /* CFF, CFF2 */

#define OpCode_Reserved2          2

#define OpCode_vstem              3 /* CFF, CFF2 */

#define OpCode_vmoveto            4 /* CFF, CFF2 */

#define OpCode_rlineto            5 /* CFF, CFF2 */

#define OpCode_hlineto            6 /* CFF, CFF2 */

#define OpCode_vlineto            7 /* CFF, CFF2 */

#define OpCode_rrcurveto          8 /* CFF, CFF2 */

#define OpCode_Reserved9          9

#define OpCode_callsubr          10 /* CFF, CFF2 */

#define OpCode_return            11 /* CFF */

//#define OpCode_escape          12 /* CFF, CFF2 */

#define OpCode_Reserved13        13

#define OpCode_endchar           14 /* CFF */

#define OpCode_vsindexcs         15 /* CFF2 */

#define OpCode_blendcs           16 /* CFF2 */

#define OpCode_Reserved17        17

#define OpCode_hstemhm           18 /* CFF, CFF2 */

#define OpCode_hintmask          19 /* CFF, CFF2 */

#define OpCode_cntrmask          20 /* CFF, CFF2 */

#define OpCode_rmoveto           21 /* CFF, CFF2 */

#define OpCode_hmoveto           22 /* CFF, CFF2 */

#define OpCode_vstemhm           23 /* CFF, CFF2 */

#define OpCode_rcurveline        24 /* CFF, CFF2 */

#define OpCode_rlinecurve        25 /* CFF, CFF2 */

#define OpCode_vvcurveto         26 /* CFF, CFF2 */

#define OpCode_hhcurveto         27 /* CFF, CFF2 */

//#define OpCode_shortint        28 /* CFF, CFF2 */

#define OpCode_callgsubr         29 /* CFF, CFF2 */

#define OpCode_vhcurveto         30 /* CFF, CFF2 */

#define OpCode_hvcurveto         31 /* CFF, CFF2 */

#define OpCode_fixedcs          255 /* 32-bit fixed */

/* Two byte escape operators 12, (0-41) */

#define OpCode_dotsection       Make_OpCode_ESC(0) /* CFF (obsoleted) */

#define OpCode_ReservedESC1     Make_OpCode_ESC(1)

#define OpCode_ReservedESC2     Make_OpCode_ESC(2)

#define OpCode_and              Make_OpCode_ESC(3) /* CFF */

#define OpCode_or               Make_OpCode_ESC(4) /* CFF */

#define OpCode_not              Make_OpCode_ESC(5) /* CFF */

#define OpCode_ReservedESC6     Make_OpCode_ESC(6)

#define OpCode_ReservedESC7     Make_OpCode_ESC(7)

#define OpCode_ReservedESC8     Make_OpCode_ESC(8)

#define OpCode_abs              Make_OpCode_ESC(9) /* CFF */

#define OpCode_add              Make_OpCode_ESC(10) /* CFF */

#define OpCode_sub              Make_OpCode_ESC(11) /* CFF */

#define OpCode_div              Make_OpCode_ESC(12) /* CFF */

#define OpCode_ReservedESC13    Make_OpCode_ESC(13)

#define OpCode_neg              Make_OpCode_ESC(14) /* CFF */

#define OpCode_eq               Make_OpCode_ESC(15) /* CFF */

#define OpCode_ReservedESC16    Make_OpCode_ESC(16)

#define OpCode_ReservedESC17    Make_OpCode_ESC(17)

#define OpCode_drop             Make_OpCode_ESC(18) /* CFF */

#define OpCode_ReservedESC19    Make_OpCode_ESC(19)

#define OpCode_put              Make_OpCode_ESC(20) /* CFF */

#define OpCode_get              Make_OpCode_ESC(21) /* CFF */

#define OpCode_ifelse           Make_OpCode_ESC(22) /* CFF */

#define OpCode_random           Make_OpCode_ESC(23) /* CFF */

#define OpCode_mul              Make_OpCode_ESC(24) /* CFF */

//#define OpCode_reservedESC25  Make_OpCode_ESC(25)

#define OpCode_sqrt             Make_OpCode_ESC(26) /* CFF */

#define OpCode_dup              Make_OpCode_ESC(27) /* CFF */

#define OpCode_exch             Make_OpCode_ESC(28) /* CFF */

#define OpCode_index            Make_OpCode_ESC(29) /* CFF */

#define OpCode_roll             Make_OpCode_ESC(30) /* CFF */

#define OpCode_reservedESC31    Make_OpCode_ESC(31)

#define OpCode_reservedESC32    Make_OpCode_ESC(32)

#define OpCode_reservedESC33    Make_OpCode_ESC(33)

#define OpCode_hflex            Make_OpCode_ESC(34) /* CFF, CFF2 */

#define OpCode_flex             Make_OpCode_ESC(35) /* CFF, CFF2 */

#define OpCode_hflex1           Make_OpCode_ESC(36) /* CFF, CFF2 */

#define OpCode_flex1            Make_OpCode_ESC(37) /* CFF, CFF2 */

#define OpCode_Invalid          0xFFFFu

struct number_t

{

  void init () { set_real (0.0); }

  void fini () {}

  void set_int (int v)       { value = (double) v; }

  int to_int () const        { return (int) value; }

  void set_fixed (int32_t v) { value = v / 65536.0; }

  int32_t to_fixed () const  { return (int32_t) (value * 65536.0); }

  void set_real (double v)       { value = v; }

  double to_real () const    { return value; }

  int ceil () const          { return (int) ::ceil (value); }

  int floor () const         { return (int) ::floor (value); }

  bool in_int_range () const

  { return ((double) (int16_t) to_int () == value); }

  bool operator > (const number_t &n) const

  { return value > n.to_real (); }

  bool operator < (const number_t &n) const

  { return n > *this; }

  bool operator >= (const number_t &n) const

  { return !(*this < n); }

  bool operator <= (const number_t &n) const

  { return !(*this > n); }

  const number_t &operator += (const number_t &n)

  {

    set_real (to_real () + n.to_real ());

    return *this;

  }

  protected:

  double  value;

};

/* byte string */

struct UnsizedByteStr : UnsizedArrayOf <HBUINT8>

{

  // encode 2-byte int (Dict/CharString) or 4-byte int (Dict)

  template <typename INTTYPE, int minVal, int maxVal>

  static bool serialize_int (hb_serialize_context_t *c, op_code_t intOp, int value)

  {

    TRACE_SERIALIZE (this);

    if (unlikely ((value < minVal || value > maxVal)))

      return_trace (false);

    HBUINT8 *p = c->allocate_size<HBUINT8> (1);

    if (unlikely (p == nullptr)) return_trace (false);

    p->set (intOp);

    INTTYPE *ip = c->allocate_size<INTTYPE> (INTTYPE::static_size);

    if (unlikely (ip == nullptr)) return_trace (false);

    ip->set ((unsigned int)value);

    return_trace (true);

  }

  static bool serialize_int4 (hb_serialize_context_t *c, int value)

  { return serialize_int<HBUINT32, 0, 0x7FFFFFFF> (c, OpCode_longintdict, value); }

  static bool serialize_int2 (hb_serialize_context_t *c, int value)

  { return serialize_int<HBUINT16, 0, 0x7FFF> (c, OpCode_shortint, value); }

  /* Defining null_size allows a Null object may be created. Should be safe because:

   * A descendent struct Dict uses a Null pointer to indicate a missing table,

   * checked before access.

   * byte_str_t, a wrapper struct pairing a byte pointer along with its length, always

   * checks the length before access. A Null pointer is used as the initial pointer

   * along with zero length by the default ctor.

   */

  DEFINE_SIZE_MIN(0);

};

/* Holder of a section of byte string within a CFFIndex entry */

struct byte_str_t : hb_ubytes_t

{

  byte_str_t ()

    : hb_ubytes_t () {}

  byte_str_t (const UnsizedByteStr& s, unsigned int l)

    : hb_ubytes_t ((const unsigned char*)&s, l) {}

  byte_str_t (const unsigned char *s, unsigned int l)

    : hb_ubytes_t (s, l) {}

  byte_str_t (const hb_ubytes_t &ub)    /* conversion from hb_ubytes_t */

    : hb_ubytes_t (ub) {}

  /* sub-string */

  byte_str_t sub_str (unsigned int offset, unsigned int len_) const

  { return byte_str_t (hb_ubytes_t::sub_array (offset, len_)); }

  bool check_limit (unsigned int offset, unsigned int count) const

  { return (offset + count <= length); }

};

/* A byte string associated with the current offset and an error condition */

struct byte_str_ref_t

{

  byte_str_ref_t ()

  { init (); }

  void init ()

  {

    str = byte_str_t ();

    offset = 0;

    error = false;

  }

  void fini () {}

  byte_str_ref_t (const byte_str_t &str_, unsigned int offset_ = 0)

    : str (str_), offset (offset_), error (false) {}

  void reset (const byte_str_t &str_, unsigned int offset_ = 0)

  {

    str = str_;

    offset = offset_;

    error = false;

  }

  const unsigned char& operator [] (int i) {

    if (unlikely ((unsigned int)(offset + i) >= str.length))

    {

      set_error ();

      return Null(unsigned char);

    }

    else

      return str[offset + i];

  }

  /* Conversion to byte_str_t */

  operator byte_str_t () const { return str.sub_str (offset, str.length - offset); }

  byte_str_t sub_str (unsigned int offset_, unsigned int len_) const

  { return str.sub_str (offset_, len_); }

  bool avail (unsigned int count=1) const

  {

    return (!in_error () && str.check_limit (offset, count));

  }

  void inc (unsigned int count=1)

  {

    if (likely (!in_error () && (offset <= str.length) && (offset + count <= str.length)))

    {

      offset += count;

    }

    else

    {

      offset = str.length;

      set_error ();

    }

  }

  void set_error ()      { error = true; }

  bool in_error () const { return error; }

  byte_str_t       str;

  unsigned int  offset; /* beginning of the sub-string within str */

  protected:

  bool    error;

};

typedef hb_vector_t<byte_str_t> byte_str_array_t;

/* stack */

template <typename ELEM, int LIMIT>

struct stack_t

{

  void init ()

  {

    error = false;

    count = 0;

    elements.init ();

    elements.resize (kSizeLimit);

    for (unsigned int i = 0; i < elements.length; i++)

      elements[i].init ();

  }

  void fini ()

  {

    elements.fini_deep ();

  }

  ELEM& operator [] (unsigned int i)

  {

    if (unlikely (i >= count)) set_error ();

    return elements[i];

  }

  void push (const ELEM &v)

  {

    if (likely (count < elements.length))

      elements[count++] = v;

    else

      set_error ();

  }

  ELEM &push ()

  {

    if (likely (count < elements.length))

      return elements[count++];

    else

    {

      set_error ();

      return Crap(ELEM);

    }

  }

  ELEM& pop ()

  {

    if (likely (count > 0))

      return elements[--count];

    else

    {

      set_error ();

      return Crap(ELEM);

    }

  }

  void pop (unsigned int n)

  {

    if (likely (count >= n))

      count -= n;

    else

      set_error ();

  }

  const ELEM& peek ()

  {

    if (likely (count > 0))

      return elements[count-1];

    else

    {

      set_error ();

      return Null(ELEM);

    }

  }

  void unpop ()

  {

    if (likely (count < elements.length))

      count++;

    else

      set_error ();

  }

  void clear () { count = 0; }

  bool in_error () const { return (error || elements.in_error ()); }

  void set_error ()      { error = true; }

  unsigned int get_count () const { return count; }

  bool is_empty () const { return count == 0; }

  static constexpr unsigned kSizeLimit = LIMIT;

  protected:

  bool error;

  unsigned int count;

  hb_vector_t<ELEM> elements;

};

/* argument stack */

template <typename ARG=number_t>

struct arg_stack_t : stack_t<ARG, 513>

{

  void push_int (int v)

  {

    ARG &n = S::push ();

    n.set_int (v);

  }

  void push_fixed (int32_t v)

  {

    ARG &n = S::push ();

    n.set_fixed (v);

  }

  void push_real (double v)

  {

    ARG &n = S::push ();

    n.set_real (v);

  }

  ARG& pop_num () { return this->pop (); }

  int pop_int ()  { return this->pop ().to_int (); }

  unsigned int pop_uint ()

  {

    int i = pop_int ();

    if (unlikely (i < 0))

    {

      i = 0;

      S::set_error ();

    }

    return (unsigned)i;

  }

  void push_longint_from_substr (byte_str_ref_t& str_ref)

  {

    push_int ((str_ref[0] << 24) | (str_ref[1] << 16) | (str_ref[2] << 8) | (str_ref[3]));

    str_ref.inc (4);

  }