src/plugins/litehtml_viewer/litehtml/num_cvt.cpp

   1 #include "num_cvt.h"
   2 #include "utf8_strings.h"
   3 #include <vector>
   4
   5 static std::vector<char> latin_lower = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z' };
   6 static std::vector<char> latin_upper = { 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };
   7 static std::vector<std::wstring> greek_lower = { L"α", L"β", L"γ", L"δ", L"ε", L"ζ", L"η", L"θ", L"ι", L"κ", L"λ", L"μ", L"ν", L"ξ", L"ο", L"π", L"ρ", L"σ", L"τ", L"υ", L"φ", L"χ", L"ψ", L"ω" };
   8
   9 static litehtml::string to_mapped_alpha(int num, const std::vector<char>& map)
  10 {
  11         int dividend = num;
  12         litehtml::string out;
  13         int modulo;
  14
  15         while (dividend > 0)
  16         {
  17                 modulo = (dividend - 1) % map.size();
  18                 out = map[modulo] + out;
  19                 dividend = (int)((dividend - modulo) / map.size());
  20         }
  21
  22         return out;
  23 }
  24
  25 static litehtml::string to_mapped_alpha(int num, const std::vector<std::wstring>& map)
  26 {
  27         int dividend = num;
  28         litehtml::string out;
  29         int modulo;
  30
  31         while (dividend > 0)
  32         {
  33                 modulo = (dividend - 1) % map.size();
  34                 out = litehtml_from_wchar(map[modulo]).c_str() + out;
  35                 dividend = (int)((dividend - modulo) / map.size());
  36         }
  37
  38         return out;
  39 }
  40
  41 litehtml::string litehtml::num_cvt::to_latin_lower(int val)
  42 {
  43         return to_mapped_alpha(val, latin_lower);
  44 }
  45
  46 litehtml::string litehtml::num_cvt::to_latin_upper(int val)
  47 {
  48         return to_mapped_alpha(val, latin_upper);
  49 }
  50
  51 litehtml::string litehtml::num_cvt::to_greek_lower(int val)
  52 {
  53         return to_mapped_alpha(val, greek_lower);
  54 }
  55
  56 litehtml::string litehtml::num_cvt::to_roman_lower(int value)
  57 {
  58         struct romandata_t { int value; const char* numeral; };
  59         const struct romandata_t romandata[] =
  60         {
  61                 { 1000, "m" }, { 900, "cm" },
  62                 { 500, "d" }, { 400, "cd" },
  63                 { 100, "c" }, { 90, "xc" },
  64                 { 50, "l" }, { 40, "xl" },
  65                 { 10, "x" }, { 9, "ix" },
  66                 { 5, "v" }, { 4, "iv" },
  67                 { 1, "i" },
  68                 { 0, nullptr } // end marker
  69         };
  70
  71         litehtml::string result;
  72         for (const romandata_t* current = romandata; current->value > 0; ++current)
  73         {
  74                 while (value >= current->value)
  75                 {
  76                         result += current->numeral;
  77                         value -= current->value;
  78                 }
  79         }
  80         return result;
  81 }
  82
  83 litehtml::string litehtml::num_cvt::to_roman_upper(int value)
  84 {
  85         struct romandata_t { int value; const char* numeral; };
  86         const struct romandata_t romandata[] =
  87         {
  88                 { 1000, "M" }, { 900, "CM" },
  89                 { 500, "D" }, { 400, "CD" },
  90                 { 100, "C" }, { 90, "XC" },
  91                 { 50, "L" }, { 40, "XL" },
  92                 { 10, "X" }, { 9, "IX" },
  93                 { 5, "V" }, { 4, "IV" },
  94                 { 1, "I" },
  95                 { 0, nullptr } // end marker
  96         };
  97
  98         litehtml::string result;
  99         for (const romandata_t* current = romandata; current->value > 0; ++current)
 100         {
 101                 while (value >= current->value)
 102                 {
 103                         result += current->numeral;
 104                         value -= current->value;
 105                 }
 106         }
 107         return result;
 108 }