// Copyright (C) 2004-2021 Artifex Software, Inc.

//

// This file is part of MuPDF.

//

// MuPDF is free software: you can redistribute it and/or modify it under the

// terms of the GNU Affero General Public License as published by the Free

// Software Foundation, either version 3 of the License, or (at your option)

// any later version.

//

// MuPDF 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 Affero General Public License for more

// details.

//

// You should have received a copy of the GNU Affero General Public License

// along with MuPDF. If not, see <https://www.gnu.org/licenses/agpl-3.0.en.html>

//

// Alternative licensing terms are available from the licensor.

// For commercial licensing, see <https://www.artifex.com/> or contact

// Artifex Software, Inc., 39 Mesa Street, Suite 108A, San Francisco,

// CA 94129, USA, for further information.

#include "mupdf/fitz.h"

#include "svg-imp.h"

#include <string.h>

#include <math.h>

int svg_is_whitespace_or_comma(int c)

{

   return (c == 0x20) || (c == 0x9) || (c == 0xD) || (c == 0xA) || (c == ',');

}

int svg_is_whitespace(int c)

{

  return (c == 0x20) || (c == 0x9) || (c == 0xD) || (c == 0xA);

}

int svg_is_alpha(int c)

{

  return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');

}

int svg_is_digit(int c)

{

  return (c >= '0' && c <= '9') ||

    (c == 'e') || (c == 'E') ||

    (c == '+') || (c == '-') || (c == '.');

}

const char *

svg_lex_number(float *fp, const char *ss)

{

  const char *s = ss;

  if (*s == '+' || *s == '-')

    ++s;

  while (*s >= '0' && *s <= '9')

    ++s;

  if (*s == '.') {

    ++s;

    while (*s >= '0' && *s <= '9')

      ++s;

  }

  if (*s == 'e' || *s == 'E') {

    ++s;

    if (*s == '+' || *s == '-')

      ++s;

    while (*s >= '0' && *s <= '9')

      ++s;

  }

  *fp = fz_atof(ss);

  return s;

}

float

svg_parse_number(const char *str, float min, float max, float inherit)

{

  float x;

  if (!strcmp(str, "inherit"))

    return inherit;

  x = fz_atof(str);

  if (x < min) return min;

  if (x > max) return max;

  return x;

}

float

svg_parse_length(const char *str, float percent, float font_size)

{

  char *end;

  float val;

  val = fz_strtof(str, &end);

  if (end == str)

    return 0; /* failed */

  if (!strcmp(end, "px")) return val;

  if (!strcmp(end, "pt")) return val * 1.0f;

  if (!strcmp(end, "pc")) return val * 12.0f;

  if (!strcmp(end, "mm")) return val * 2.83464567f;

  if (!strcmp(end, "cm")) return val * 28.3464567f;

  if (!strcmp(end, "in")) return val * 72.0f;

  if (!strcmp(end, "em")) return val * font_size;

  if (!strcmp(end, "ex")) return val * font_size * 0.5f;

  if (!strcmp(end, "%"))

    return val * percent * 0.01f;

  if (end[0] == 0)

    return val;

  return 0;

}

/* Return angle in degrees */

float

svg_parse_angle(const char *str)

{

  char *end;

  float val;

  val = fz_strtof(str, &end);

  if (end == str)

    return 0; /* failed */

  if (!strcmp(end, "deg"))

    return val;

  if (!strcmp(end, "grad"))

    return val * 0.9f;

  if (!strcmp(end, "rad"))

    return val * FZ_RADIAN;

  return val;

}

/* Coordinate transformations */

fz_matrix

svg_parse_transform(fz_context *ctx, svg_document *doc, const char *str, fz_matrix transform)

{

  char keyword[20];

  int keywordlen;

  float args[6];

  int nargs;

  nargs = 0;

  keywordlen = 0;

  while (*str)

  {

    while (svg_is_whitespace_or_comma(*str))

      str ++;

    if (*str == 0)

      break;

    /*

     * Parse keyword and opening parenthesis.

     */

    keywordlen = 0;

    while (svg_is_alpha(*str) && keywordlen < (int)sizeof(keyword) - 1)

      keyword[keywordlen++] = *str++;

    keyword[keywordlen] = 0;

    if (keywordlen == 0)

      fz_throw(ctx, FZ_ERROR_SYNTAX, "expected keyword in transform attribute");

    while (svg_is_whitespace(*str))

      str ++;

    if (*str != '(')

      fz_throw(ctx, FZ_ERROR_SYNTAX, "expected opening parenthesis in transform attribute");

    str ++;

    /*

     * Parse list of numbers until closing parenthesis

     */

    nargs = 0;

    while (*str && *str != ')' && nargs < 6)

    {

      while (svg_is_whitespace_or_comma(*str))

        str ++;

      if (svg_is_digit(*str))

        str = svg_lex_number(&args[nargs++], str);

      else

        break;

    }

    if (*str != ')')

      fz_throw(ctx, FZ_ERROR_SYNTAX, "expected closing parenthesis in transform attribute");

    str ++;

    /*

     * Execute the transform.

     */

    if (!strcmp(keyword, "matrix"))

    {

      if (nargs != 6)

        fz_throw(ctx, FZ_ERROR_SYNTAX, "wrong number of arguments to matrix(): %d", nargs);

      transform = fz_concat(fz_make_matrix(args[0], args[1], args[2], args[3], args[4], args[5]), transform);

    }

    else if (!strcmp(keyword, "translate"))

    {

      if (nargs == 1)

        transform = fz_concat(fz_translate(args[0], 0), transform);

      else if (nargs == 2)

        transform = fz_concat(fz_translate(args[0], args[1]), transform);

      else

        fz_throw(ctx, FZ_ERROR_SYNTAX, "wrong number of arguments to translate(): %d", nargs);

    }

    else if (!strcmp(keyword, "scale"))

    {

      if (nargs == 1)

        transform = fz_concat(fz_scale(args[0], args[0]), transform);

      else if (nargs == 2)

        transform = fz_concat(fz_scale(args[0], args[1]), transform);

      else

        fz_throw(ctx, FZ_ERROR_SYNTAX, "wrong number of arguments to scale(): %d", nargs);

    }

    else if (!strcmp(keyword, "rotate"))

    {

      if (nargs == 1)

        transform = fz_concat(fz_rotate(args[0]), transform);

      else if (nargs == 3)

      {

        transform = fz_concat(fz_translate(args[1], args[2]), transform);

        transform = fz_concat(fz_rotate(args[0]), transform);

        transform = fz_concat(fz_translate(-args[1], -args[2]), transform);

      }

      else

        fz_throw(ctx, FZ_ERROR_SYNTAX, "wrong number of arguments to rotate(): %d", nargs);

    }

    else if (!strcmp(keyword, "skewX"))

    {

      if (nargs != 1)

        fz_throw(ctx, FZ_ERROR_SYNTAX, "wrong number of arguments to skewX(): %d", nargs);

      transform = fz_concat(fz_make_matrix(1, 0, tanf(args[0] * FZ_DEGREE), 1, 0, 0), transform);

    }

    else if (!strcmp(keyword, "skewY"))

    {

      if (nargs != 1)

        fz_throw(ctx, FZ_ERROR_SYNTAX, "wrong number of arguments to skewY(): %d", nargs);

      transform = fz_concat(fz_make_matrix(1, tanf(args[0] * FZ_DEGREE), 0, 1, 0, 0), transform);

    }

    else

    {

      fz_throw(ctx, FZ_ERROR_SYNTAX, "unknown transform function: %s", keyword);

    }

  }

  return transform;

}

float

svg_parse_number_from_style(fz_context *ctx, svg_document *doc, const char *style, const char *att, float number)

{

  if (style)

  {

    char *end, *p = strstr(style, att);

    if (p)

    {

      size_t n = strlen(att);

      if (p[n] == ':')

      {

        p += n + 1;

        while (*p && svg_is_whitespace(*p))

          ++p;

        number = fz_strtof(p, &end);

        if (end[0] == 'i' && end[1] == 'n') return number * 72;

        if (end[0] == 'c' && end[1] == 'm') return number * 7200 / 254;

        if (end[0] == 'm' && end[1] == 'm') return number * 720 / 254;

        if (end[0] == 'p' && end[1] == 'c') return number * 12;

      }

    }

  }

  return number;

}

int

svg_parse_enum_from_style(fz_context *ctx, svg_document *doc, const char *style, const char *att,

  int ecount, const char *etable[], int value)

{

  char buf[100], *end, *p;

  int i;

  if (style)

  {

    p = strstr(style, att);

    if (p)

    {

      size_t n = strlen(att);

      if (p[n] == ':')

      {

        p += n + 1;

        while (*p && svg_is_whitespace(*p))

          ++p;

        fz_strlcpy(buf, p, sizeof buf);

        end = strchr(buf, ';');

        if (end)

          *end = 0;

        for (i = 0; i < ecount; ++i)

          if (!strcmp(etable[i], buf))

            return i;

      }

    }

  }

  return value;

}

char *

svg_parse_string_from_style(fz_context *ctx, svg_document *doc, const char *style, const char *att,

  char *buf, int buf_size, const char *value)

{

  char *end, *p, quote;

  if (style)

  {

    p = strstr(style, att);

    if (p)

    {

      size_t n = strlen(att);

      if (p[n] == ':')

      {

        p += n + 1;

        while (*p && svg_is_whitespace(*p))

          ++p;

        quote = *p;

        if (quote == '\'' || quote == '"')

        {

          fz_strlcpy(buf, p+1, buf_size);

          end = strchr(buf, quote);

        }

        else

        {

          fz_strlcpy(buf, p, buf_size);

          end = strchr(buf, ';');

        }

        if (end)

          *end = 0;

        return buf;

      }

    }

  }

  fz_strlcpy(buf, value, buf_size);

  return buf;

}