Menu screen prototype, refactor

src/util/stringutil.cpp

@@ -3,6 +3,7 @@
 #include <vector>
 #include <locale>
 #include <sstream>
+#include <stdexcept>
 
 using std::vector;
 using std::string;
@@ -10,7 +11,7 @@ using std::stringstream;
 using std::wstring;
 using std::wstringstream;
 
-wstring lfill(wstring s, uint length, wchar_t c) {
+wstring util::lfill(wstring s, uint length, wchar_t c) {
     if (s.length() >= length) {
         return s;
     }
@@ -22,7 +23,7 @@ wstring lfill(wstring s, uint length, wchar_t c) {
     return ss.str();
 }
 
-wstring rfill(wstring s, uint length, wchar_t c) {
+wstring util::rfill(wstring s, uint length, wchar_t c) {
     if (s.length() >= length) {
         return s;
     }
@@ -34,7 +35,7 @@ wstring rfill(wstring s, uint length, wchar_t c) {
     return ss.str();
 }
 
-uint encode_utf8(uint c, ubyte* bytes) {
+uint util::encode_utf8(uint32_t c, ubyte* bytes) {
     if (c < 0x80) {
         bytes[0] = c >> 0 & 0x7F | 0x00;
         return 1;
@@ -56,7 +57,52 @@ uint encode_utf8(uint c, ubyte* bytes) {
     }
 }
 
-string wstr2str_utf8(const wstring ws) {
+struct utf_t {
+	char mask;
+	char lead;
+	uint32_t beg;
+	uint32_t end;
+	int bits_stored;
+};
+
+const utf_t utf[] = {
+	/*             mask        lead        beg      end       bits */
+	{(char)0b00111111, (char)0b10000000, 0,       0,        6},
+	{(char)0b01111111, (char)0b00000000, 0000,    0177,     7},
+	{(char)0b00011111, (char)0b11000000, 0200,    03777,    5},
+	{(char)0b00001111, (char)0b11100000, 04000,   0177777,  4},
+	{(char)0b00000111, (char)0b11110000, 0200000, 04177777, 3},
+	{0, 0, 0, 0, 0},
+};
+
+
+inline uint utf8_len(ubyte cp) {
+    uint len = 0;
+	for (const utf_t* u = utf; u->mask; ++u) {
+		if((cp >= u->beg) && (cp <= u->end)) {
+			break;
+		}
+		++len;
+	}
+	if(len > 4) /* Out of bounds */
+		throw std::runtime_error("utf-8 decode error");
+
+	return len;
+}
+
+extern uint32_t util::decode_utf8(uint& size, const char* chr) {
+	size = utf8_len(*chr);
+	int shift = utf[0].bits_stored * (size - 1);
+	uint32_t code = (*chr++ & utf[size].mask) << shift;
+
+	for(uint i = 1; i < size; ++i, ++chr) {
+		shift -= utf[0].bits_stored;
+		code |= ((char)*chr & utf[0].mask) << shift;
+	}
+    return code;
+}
+
+string util::wstr2str_utf8(const wstring ws) {
     vector<char> chars;
     char buffer[4];
     for (wchar_t wc : ws) {
@@ -66,4 +112,23 @@ string wstr2str_utf8(const wstring ws) {
         }
     }
     return string(chars.data(), chars.size());
+}
+
+wstring util::str2wstr_utf8(const string s) {
+    vector<wchar_t> chars;
+    size_t pos = 0;
+    uint size = 0;
+    while (pos < s.length()) {
+        chars.push_back(decode_utf8(size, &s.at(pos)));
+        pos += size;
+    }
+    return wstring(chars.data(), chars.size());
+}
+
+bool util::is_integer(string text) {
+    for (char c : text) {
+        if (c < '0' || c > '9')
+            return false;
+    }
+    return true;
 }

src/util/stringutil.h

@@ -4,10 +4,15 @@
 #include <string>
 #include "../typedefs.h"
 
-extern std::wstring lfill(std::wstring s, uint length, wchar_t c);
-extern std::wstring rfill(std::wstring s, uint length, wchar_t c);
+namespace util {
+    extern std::wstring lfill(std::wstring s, uint length, wchar_t c);
+    extern std::wstring rfill(std::wstring s, uint length, wchar_t c);
 
-extern uint encode_utf8(uint c, ubyte* bytes);
-extern std::string wstr2str_utf8(const std::wstring ws);
+    extern uint encode_utf8(uint32_t c, ubyte* bytes);
+    extern uint32_t decode_utf8(uint& size, const char* bytes);
+    extern std::string wstr2str_utf8(const std::wstring ws);
+    extern std::wstring str2wstr_utf8(const std::string s);
+    extern bool is_integer(std::string text);
+}
 
 #endif // UTIL_STRINGUTIL_H_