#pragma once
#ifndef ULE_STRING_H
#define ULE_STRING_H

#include "config.h"
#include "types.h"
#include "alloc.h"

#include <cstring> // memcpy, memset, memcmp

#define STB_SPRINTF_IMPLEMENTATION
#define STB_SPRINTF_STATIC
#include <stb/stb_sprintf.h>

#define STR_ASSERT assert
#define STR_IMPLEMENTATION
#define STR_SUPPORT_STD_STRING 0
#define STR_DEFINE_STR32 0 // the type Str32, which would normally be available, conflicts with a type in MacTypes.h


static Allocator* _stringClassAllocator = &Allocator::GetDefault(); // only used for the string class, string functions you pass an allocator if it allocates

// 'String' is a datatype, but it also is a namespace for a bunch of static 'char*' operations that 
// you would normally find in the <cstring> or <string.h> header
// The datatype is a modified version of a string class developed by Omar Cornut: https://github.com/ocornut/str
class String {
public:
    // Static empty buffer we can point to for empty strings
    // Pointing to a literal increases the like-hood of getting a crash if someone attempts to write in the empty string buffer.
    constexpr static char* EmptyBuffer = (char*) "\0NULL";

    constexpr static unsigned char ASCII_LOWER[128] = {
        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
        16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
        32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
        48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
        64, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
        112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 91, 92, 93, 94, 95,
        96, 97, 98, 99, 100,101,102,103,104,105,106,107,108,109,110,111,
        112,113,114,115,116,117,118,119,120,121,122,123,124,125,126,127
    };
    constexpr static unsigned char ASCII_UPPER[128] = {
        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
        16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
        32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
        48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
        64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
        80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
        96, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
        80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90,123,124,125,126,127
    };

    static inline s32 sprintf(char* buffer, const char* format, ...) {
        ULE_TYPES_H_FTAG;
        va_list args;
        va_start(args, format);

        s32 code = stbsp_vsprintf(buffer, format, args);
        va_end(args);

        return code;
    }
    static inline s32 snprintf(char* buffer, s32 count, const char* format, ...) {
        ULE_TYPES_H_FTAG;
        va_list args;
        va_start(args, format);

        s32 code = stbsp_vsnprintf(buffer, count, format, args);
        va_end(args);

        return code;
    }
    static inline s32 vsnprintf(char* buffer, int count, const char* format, va_list args) {
        return stbsp_vsnprintf(buffer, count, format, args);
    }

    static inline bool isDigit(char c) {
        ULE_TYPES_H_FTAG;
        return (c >= '0') && (c <= '9');
    }
    static inline bool isAlpha(char c) {
        ULE_TYPES_H_FTAG;
        return (c >= 'A' && c <= 'Z')
            || (c >= 'a' && c <= 'z');
    }
    static inline bool isHexDigit(char c) {
        ULE_TYPES_H_FTAG;
        return ((c >= '0') && (c <= '9'))
            || ((c >= 'A') && (c <= 'F'))
            || ((c >= 'a') && (c <= 'f'));
    }
    static inline bool isOctalDigit(char c) {
        ULE_TYPES_H_FTAG;
        return (c >= '0') && (c <= '7');
    }
    static inline bool isBinaryDigit(char c) {
        ULE_TYPES_H_FTAG;
        return c == '0' || c == '1';
    }

    static inline char* intToString(u64 integer) { // @ALLOC
        ULE_TYPES_H_FTAG;
        u32 capacity = 10;
        u32* remainders = (u32*) pMalloc(sizeof (u32) * capacity);

        u32 count = 0;
        while (true) {
            if (capacity <= count) {
                capacity *= 2;
                remainders = (u32*) pRealloc(remainders, sizeof (u32) * capacity);
            }

            remainders[count++] = integer % 10;
            integer /= 10;
            if (integer == 0) break;
        }

        char* buffer = (char*) pMalloc(sizeof (char) * count + 1);
        for (u32 i = 0; i < count; i++) {
            buffer[count - i - 1] = '0' + remainders[i];
        }

        buffer[count] = '\0';
        pFree(remainders);
        return buffer;
    }

    static inline u64 hexStringToInt(const char* str) {
        ULE_TYPES_H_FTAG;
        u64 out = 0;

        while (*str != '\0') {
            u8 byte = *str++;

            if ((byte >= '0') && (byte <= '9')) {
                byte = byte - '0';

            } else if ((byte >= 'a') && (byte <= 'f')) {
                byte = byte - 'a' + 10;

            } else if ((byte >= 'A') && (byte <= 'F')) {
                byte = byte - 'A' + 10;
            }

            // only use the last four bits - precision of a single hex digit
            out = (out << 4) | (byte & 0xF);
        }

        return out;
    }

    static inline u32 len(const char* string) {
        ULE_TYPES_H_FTAG;
        const char* start = string;
        while (*string++ != '\0') {}
        return (u32) (string - start);
    }

    // returns true if null-terminated strings |s1| and |s2| are equal
    static inline bool eq(const char* s1, const char* s2) {
        ULE_TYPES_H_FTAG;
        u32 l1 = String::len(s1);
        u32 l2 = String::len(s2);

        if (l1 != l2) return false;

        for (u32 i = 0; i < l1; i++) {
            if (s1[i] != s2[i]) {
                return false;
            }
        }

        return true;
    }

    // same as |eq|, but handles |s1| and/or |s2| being null
    static inline bool eqNullCheck(const char* s1, const char* s2) {
        ULE_TYPES_H_FTAG;
        if (s1 == null) {
            if (s2 == null) {
                return true;
            } else {
                return false;
            }
        } else if (s2 == null) {
            return false;
        }

        return String::eq(s1, s2);
    }

    // heap allocates a copy of |string| and returns a pointer to it.
    static inline char* cpy(const char* string, u32 length, Allocator& allocator = Allocator::GetDefault()) {
        ULE_TYPES_H_FTAG;
        assert(&allocator == &Allocator::GetDefault());
        char* buffer = (char*) pMalloc(sizeof(char) * (length+1)); //allocator.mallocate(sizeof (char) * (length + 1), allocator.state);

        u32 i = 0;
        for (; i < length; i++) {
            buffer[i] = string[i];
        }
        buffer[i] = '\0';

        return buffer;
    }

    // heap allocates a copy of |string| and returns a pointer to it.
    static inline char* cpy(const char* string, Allocator& allocator = Allocator::GetDefault()) {
        ULE_TYPES_H_FTAG;
        u32 len = String::len(string);
        return String::cpy(string, len, allocator = Allocator::GetDefault());
    }

    static inline bool memeq(const unsigned char* m1, const unsigned char* m2, size_t length) {
        ULE_TYPES_H_FTAG;
        return memcmp(m1, m2, length) == 0;
    }
    static inline bool memeq(const unsigned char* m1, size_t l1, const unsigned char* m2, size_t l2) {
        ULE_TYPES_H_FTAG;
        if (l1 != l2) return false;

        return memeq(m1, m2, l1);
    }

    // assumes null termination.
    static inline bool LexographicComparisonASCII(const char* str1, const char* str2) {
        u32 min;

        const u32 l1 = String::len(str1);
        const u32 l2 = String::len(str2);
        if (l1 > l2) {
            min = l2;
        } else {
            min = l1;
        }

        for (u32 i = 0; i < min; i++) {
            if (str1[i] < str2[i]) {
                return true;

            } else if (str1[i] > str2[i]) {
                return false;
            }
        }

        return l1 < l2;
    }

    #ifdef _WIN32
    static inline size_t wcharToChar(wchar_t* wstring, char* buffer, size_t maxBufferLength) {
        ULE_TYPES_H_FTAG;
        return wcstombs(buffer, wstring, maxBufferLength);
    }
    #endif

    static inline void* memset(void* p, char c, u32 length) {
        ULE_TYPES_H_FTAG;
        //__stosb((unsigned char*) p, c, length);
        char* a = (char*) p;
        for (u32 i = 0; i < length; i++) a[i] = c;
        return a;
    }

    static inline void memcpy(void* dest, void* src, u32 size) {
        ULE_TYPES_H_FTAG;
        // allowing c++ compilers to know we're invoking memcpy allows more aggressive optimizations, sometimes resulting in 8-9x speedup,
        // when compared to the horrible, commented out loop below.
        std::memcpy(dest, src, size); 

        //u8* dest_ = (u8*) dest;
        //u8* src_ = (u8*) src;

        //for (u32 i = 0; i < size; i++) {
        //    dest_[i] = src_[i];
        //}
    }

    // replace all instances of |c1| in |string| with |c2|
    static inline void replaceC(char* string, u32 length, char c1, char c2) {
        ULE_TYPES_H_FTAG;
        for (u32 i = 0; i < length; i++) {
            if (string[i] == c1) {
                string[i] = c2;
            }
        }
    }

    static inline const char* firstCharOccurence(const char* string, u32 length, char c) {
        ULE_TYPES_H_FTAG;
        for (u32 i = 0; i < length; i++) {
            const char* s = string + i;
            if (*s == c) {
                return s;
            }
        }
        return null;
    }

    static inline const char* firstCharOccurence(const char* string, char c) {
        ULE_TYPES_H_FTAG;
        return String::firstCharOccurence(string, String::len(string), c);
    }

    static inline const char* lastCharOccurence(const char* string, u32 length, char c) {
        ULE_TYPES_H_FTAG;
        for (s32 i = length - 1; i >= 0; i--) { // @NOTE 'i' needs to be a signed int here...
            if (*(string + i) == c) {
                return string + i;
            }
        }
        return null;
    }

    static inline const char* lastCharOccurence(const char* string, char c) {
        ULE_TYPES_H_FTAG;
        return String::lastCharOccurence(string, String::len(string), c);
    }

    static inline bool hasSuffix(const char* string, const char* suffix) {
        ULE_TYPES_H_FTAG;
        const char* p = String::lastCharOccurence(string, String::len(string), suffix[0]);
        if (p) return String::eq(p, suffix);
        return false;
    }

    static inline u32 countLines(const char* buffer) {
        ULE_TYPES_H_FTAG;
        u32 lines = 0;
        char c;

        while ((c = *buffer) != '\0') {
            if (c == '\n') lines++;
            buffer++;
        }
        return lines;
    }

    static inline bool isAscii(const char* buffer, u32 length) {
        ULE_TYPES_H_FTAG;
        const unsigned char* ubuffer = (const unsigned char*) buffer;
        for (u32 i = 0; i < length; i++) {
            if (ubuffer[i] & 128) { // binary: 0b 1000 0000
                return false;
            }
        }
        return true;
    }

    static inline bool isAsciiWhitespace(char c) {
        ULE_TYPES_H_FTAG;
        switch (c) {
            //case '\b':
            //case '\v':
            //case '\f':

            case '\r':
            case '\t':
            case '\n':
            case ' ':
                return true;

            default:
                return false;
        }
    }
    // static inline bool isUnicodeSpaceSeparator(wide character);

    // @TODO ALL OF THESE TRIMS
    //static inline char* trimStart(const char* str, u32 count);
    //static inline char* trimEnd(const char* str, u32 count);
    static inline char* trim(const char* str, u32 count, Allocator& allocator = Allocator::GetDefault()) {
        ULE_TYPES_H_FTAG;
        u32 length = String::len(str);

        if (length <= count) {
            return (char*) "";
        }

        char* buffer = (char*) allocator.mallocate(sizeof (char) * (length - 1), allocator.state);

        u32 i = 0;
        for (; i < (length - count); i++) {
            buffer[i] = str[i + 1];
        }

        buffer[i] = '\0';

        return buffer;
    }

    static inline char* asciiToLower(const char* str, Allocator& allocator = Allocator::GetDefault()) {
        ULE_TYPES_H_FTAG;
        u32 length = String::len(str);
        char* buffer = (char*) allocator.mallocate(sizeof (char) * length + 1, allocator.state);
        u32 i = 0;
        for (; i < length; i++) {
            buffer[i] = String::ASCII_LOWER[str[i]];
        }
        buffer[i] = '\0';
        return buffer;
    }

    static inline char* asciiToUpper(const char* str, Allocator& allocator = Allocator::GetDefault()) {
        ULE_TYPES_H_FTAG;
        u32 length = String::len(str);
        char* buffer = (char*) allocator.mallocate(sizeof (char) * length + 1, allocator.state);
        u32 i = 0;
        for (; i < length; i++) {
            buffer[i] = String::ASCII_LOWER[str[i]];
        }
        buffer[i] = '\0';
        return buffer;
    }

    static inline char* concat(const char* str1, const char* str2, Allocator& allocator = Allocator::GetDefault()) {
        ULE_TYPES_H_FTAG;
        u32 l1 = String::len(str1);
        u32 l2 = String::len(str2);
        u32 newLength = l1 + l2;
        char* newBuffer = (char*) allocator.mallocate(sizeof (char) * newLength + 1, allocator.state);
        u32 i = 0;
        for (; i < newLength; i++) {
            if (i < l1) {
                newBuffer[i] = str1[i];
            } else {
                newBuffer[i] = str2[i - l1];
            }
        }
        newBuffer[i] = '\0';
        return newBuffer;
    }

    static inline u32 write(char* dest, const char* src, u32 length) {
        ULE_TYPES_H_FTAG;
        u32 i = 0;
        for (; i < length; i++) {
            dest[i] = src[i];
        }
        dest[i] = '\0';
        return i;
    }

    // returns the number of characters written.
    static inline u32 write(char* dest, const char* src) {
        ULE_TYPES_H_FTAG;
        u32 length = String::len(src);
        return String::write(dest, src, length);
    }

    static inline char* read(const char* buffer, u32 length, Allocator& allocator = Allocator::GetDefault()) {
        ULE_TYPES_H_FTAG;
        char* tk = (char*) allocator.mallocate(sizeof (char) * length + 1, allocator.state);
        u32 i = 0;
        while (i < length) {
            tk[i] = *(buffer + i);
            i++;
        }
        tk[i] = '\0';
        return tk;
    }

    //---------------------------------------------------------------
    // Begin String class type
    static inline void SetStringClassAllocator(Allocator* allocator) {
        _stringClassAllocator = allocator;
    }

    char*               Data;                   // Point to LocalBuf() or heap allocated
    int                 Capacity : 21;          // Max 2 MB
    int                 LocalBufSize : 10;      // Max 1023 bytes
    unsigned int        Owned : 1;              // Set when we have ownership of the pointed data (most common, unless using set_ref() method or StringRef constructor)

    inline char*        c_str()                                 { ULE_TYPES_H_FTAG; return Data; }
    inline const char*  c_str() const                           { ULE_TYPES_H_FTAG; return Data; }
    inline bool         empty() const                           { ULE_TYPES_H_FTAG; return Data[0] == 0; }
    inline int          length() const                          { ULE_TYPES_H_FTAG; return (int)strlen(Data); }    // by design, allow user to write into the buffer at any time
    inline int          capacity() const                        { ULE_TYPES_H_FTAG; return Capacity; }
    inline bool         owned() const                           { ULE_TYPES_H_FTAG; return Owned ? true : false; }

    inline char&        operator[](size_t i)                    { ULE_TYPES_H_FTAG; return Data[i]; }
    inline char         operator[](size_t i) const              { ULE_TYPES_H_FTAG; return Data[i]; }
    inline String&      operator=(const String& rhs)            { ULE_TYPES_H_FTAG; set(rhs); return *this; }
    inline bool         operator==(const String& rhs) const     { ULE_TYPES_H_FTAG; return strcmp(c_str(), rhs.c_str()) == 0; }
    inline String&      operator=(const char* rhs)              { ULE_TYPES_H_FTAG; set(rhs); return *this; }
    inline bool         operator==(const char* rhs) const       { ULE_TYPES_H_FTAG; return strcmp(c_str(), rhs) == 0; }

    inline String() {
        ULE_TYPES_H_FTAG; 
        Data = EmptyBuffer; // Shared READ-ONLY initial buffer for 0 capacity
        Capacity = 0;
        LocalBufSize = 0;
        Owned = 0;
    }
    inline String(const String& rhs) : String() {
        ULE_TYPES_H_FTAG; 
        set(rhs);
    }
    inline String(const char* rhs) : String() {
        ULE_TYPES_H_FTAG; 
        set(rhs);
    }

    inline void set_ref(const char* src) {
        ULE_TYPES_H_FTAG; 
        if (Owned && !is_using_local_buf())
            _stringClassAllocator->free(Data, null);
        Data = src ? (char*)src : EmptyBuffer;
        Capacity = 0;
        Owned = 0;
    }
    inline void set(const String& src) {
        ULE_TYPES_H_FTAG; 
        int buf_len = (int)strlen(src.c_str())+1;
        if ((int)Capacity < buf_len)
            reserve_discard(buf_len);
        memcpy(Data, (void*)src.c_str(), (size_t)buf_len);
        Owned = 1;
    }

    inline void set(const char* src) {
        ULE_TYPES_H_FTAG; 
        // We allow set(NULL) or via = operator to clear the string.
        if (src == NULL)
        {
            clear();
            return;
        }
        int buf_len = (int)strlen(src)+1;
        if (Capacity < buf_len)
            reserve_discard(buf_len);
        memcpy(Data, (void*)src, (size_t)buf_len);
        Owned = 1;
    }

    inline void set(const char* src, const char* src_end) {
        ULE_TYPES_H_FTAG; 
        STR_ASSERT(src != NULL && src_end >= src);
        int buf_len = (int)(src_end-src)+1;
        if ((int)Capacity < buf_len)
            reserve_discard(buf_len);
        memcpy(Data, (void*)src, (size_t)(buf_len - 1));
        Data[buf_len-1] = 0;
        Owned = 1;
    }

    // Clear
    inline void clear() {
        ULE_TYPES_H_FTAG; 
        if (Owned && !is_using_local_buf())
            _stringClassAllocator->free(Data, null);
        if (LocalBufSize) {
            Data = local_buf();
            Data[0] = '\0';
            Capacity = LocalBufSize;
            Owned = 1;
        } else {
            Data = EmptyBuffer;
            Capacity = 0;
            Owned = 0;
        }
    }

    // Reserve memory, preserving the current of the buffer
    inline void reserve(int new_capacity) {
        ULE_TYPES_H_FTAG; 
        if (new_capacity <= Capacity)
            return;

        char* new_data;
        if (new_capacity < LocalBufSize) {
            // Disowned -> LocalBuf
            new_data = local_buf();
            new_capacity = LocalBufSize;
        } else {
            // Disowned or LocalBuf -> Heap
            new_data = (char*)_stringClassAllocator->mallocate((size_t)new_capacity * sizeof(char), null);
        }

        // string in Data might be longer than new_capacity if it wasn't owned, don't copy too much
        #ifdef _MSC_VER
        strncpy_s(new_data, (size_t)new_capacity, Data, (size_t)new_capacity - 1);
        #else
        strncpy(new_data, Data, (size_t)new_capacity - 1);
        #endif
        new_data[new_capacity - 1] = 0;

        if (Owned && !is_using_local_buf())
            _stringClassAllocator->free(Data, null);

        Data = new_data;
        Capacity = new_capacity;
        Owned = 1;
    }

    // Reserve memory, discarding the current of the buffer (if we expect to be fully rewritten)
    inline void reserve_discard(int new_capacity) {
        ULE_TYPES_H_FTAG; 
        if (new_capacity <= Capacity)
            return;

        if (Owned && !is_using_local_buf())
            _stringClassAllocator->free(Data, null);

        if (new_capacity < LocalBufSize) {
            // Disowned -> LocalBuf
            Data = local_buf();
            Capacity = LocalBufSize;
        } else {
            // Disowned or LocalBuf -> Heap
            Data = (char*)_stringClassAllocator->mallocate((size_t)new_capacity * sizeof(char), null);
            Capacity = new_capacity;
        }
        Owned = 1;
    }

    inline void shrink_to_fit() {
        ULE_TYPES_H_FTAG; 
        if (!Owned || is_using_local_buf()) return;
        int new_capacity = length() + 1;
        if (Capacity <= new_capacity) return;

        char* new_data = (char*)_stringClassAllocator->mallocate((size_t)new_capacity * sizeof(char), null);
        memcpy(new_data, Data, (size_t)new_capacity);
        _stringClassAllocator->free(Data, null);
        Data = new_data;
        Capacity = new_capacity;
    }

    // FIXME: merge setfv() and appendfv()?
    inline int setfv(const char* fmt, va_list args) {
        ULE_TYPES_H_FTAG; 
        // Needed for portability on platforms where va_list are passed by reference and modified by functions
        va_list args2;
        va_copy(args2, args);

        // First try
        int len = vsnprintf(Owned ? Data : NULL, Owned ? (size_t)Capacity : 0, fmt, args);
        STR_ASSERT(len >= 0);

        if (Capacity < len + 1)
        {
            reserve_discard(len + 1);
            len = vsnprintf(Data, (size_t)len + 1, fmt, args2);
        }

        STR_ASSERT(Owned);
        return len;
    }

    inline int setf(const char* fmt, ...) {
        ULE_TYPES_H_FTAG; 
        va_list args;
        va_start(args, fmt);
        int len = setfv(fmt, args);
        va_end(args);
        return len;
    }

    inline int setfv_nogrow(const char* fmt, va_list args) {
        ULE_TYPES_H_FTAG; 
        STR_ASSERT(Owned);

        if (Capacity == 0) return 0;

        int w = vsnprintf(Data, (size_t)Capacity, fmt, args);
        Data[Capacity - 1] = 0;
        Owned = 1;
        return (w == -1) ? Capacity - 1 : w;
    }

    inline int setf_nogrow(const char* fmt, ...) {
        ULE_TYPES_H_FTAG; 
        va_list args;
        va_start(args, fmt);
        int len = setfv_nogrow(fmt, args);
        va_end(args);
        return len;
    }

    inline int append_from(int idx, char c) {
        ULE_TYPES_H_FTAG; 
        int add_len = 1;
        if (Capacity < idx + add_len + 1)
            reserve(idx + add_len + 1);
        Data[idx] = c;
        Data[idx + add_len] = 0;
        STR_ASSERT(Owned);
        return add_len;
    }

    inline int append_from(int idx, const char* s, const char* s_end) {
        ULE_TYPES_H_FTAG;
        if (!s_end) s_end = s + strlen(s);
        int add_len = (int)(s_end - s);
        if (Capacity < idx + add_len + 1) reserve(idx + add_len + 1);
        memcpy(Data + idx, (void*)s, (size_t)add_len);
        Data[idx + add_len] = 0; // Our source data isn't necessarily zero-terminated
        STR_ASSERT(Owned);
        return add_len;
    }

    // FIXME: merge setfv() and appendfv()?
    inline int appendfv_from(int idx, const char* fmt, va_list args) {
        ULE_TYPES_H_FTAG; 
        // Needed for portability on platforms where va_list are passed by reference and modified by functions
        va_list args2;
        va_copy(args2, args);

        // First try
        int add_len = vsnprintf(Owned ? Data + idx : NULL, Owned ? (size_t)(Capacity - idx) : 0, fmt, args);
        STR_ASSERT(add_len >= 0);

        if (Capacity < idx + add_len + 1) {
            reserve(idx + add_len + 1);
            add_len = vsnprintf(Data + idx, (size_t)add_len + 1, fmt, args2);
        }

        STR_ASSERT(Owned);
        return add_len;
    }

    inline int appendf_from(int idx, const char* fmt, ...) {
        ULE_TYPES_H_FTAG; 
        va_list args;
        va_start(args, fmt);
        int len = appendfv_from(idx, fmt, args);
        va_end(args);
        return len;
    }

    inline int append(char c) {
        ULE_TYPES_H_FTAG; 
        int cur_len = length();
        return append_from(cur_len, c);
    }

    inline int append(const char* s, const char* s_end = null) {
        ULE_TYPES_H_FTAG; 
        int cur_len = length();
        return append_from(cur_len, s, s_end);
    }

    inline int appendfv(const char* fmt, va_list args) {
        ULE_TYPES_H_FTAG;
        int cur_len = length();
        return appendfv_from(cur_len, fmt, args);
    }

    int appendf(const char* fmt, ...) {
        ULE_TYPES_H_FTAG;
        va_list args;
        va_start(args, fmt);
        int len = appendfv(fmt, args);
        va_end(args);
        return len;
    }

    // Destructor for all variants
    inline ~String()
    {
        if (Owned && !is_using_local_buf())
            if (_stringClassAllocator->free != null) ::_stringClassAllocator->free(Data, null);
    }

protected:
    inline char*        local_buf()                             { ULE_TYPES_H_FTAG; return (char*)this + sizeof(String); }
    inline const char*  local_buf() const                       { ULE_TYPES_H_FTAG; return (char*)this + sizeof(String); }
    inline bool         is_using_local_buf() const              { ULE_TYPES_H_FTAG; return Data == local_buf() && LocalBufSize != 0; }

    // Constructor for StringXXX variants with local buffer
    String(unsigned short local_buf_size) {
        ULE_TYPES_H_FTAG; 
        STR_ASSERT(local_buf_size < 1024);
        Data = local_buf();
        Data[0] = '\0';
        Capacity = local_buf_size;
        LocalBufSize = local_buf_size;
        Owned = 1;
    }
};

// Literal/reference string
class StringRef : public String {
public:
    StringRef(const char* s) : String() { ULE_TYPES_H_FTAG; set_ref(s); }
};

// Types embedding a local buffer
// NB: we need to override the constructor and = operator for both String& and TYPENAME (without the later compiler will call a default copy operator)
#define STR_DEFINETYPE(TYPENAME, LOCALBUFSIZE)                                                     \
class TYPENAME : public String                                                                     \
{                                                                                                  \
    char local_buf[LOCALBUFSIZE];                                                                  \
public:                                                                                            \
    TYPENAME() : String(LOCALBUFSIZE) {}                                                           \
    TYPENAME(const String& rhs) : String(LOCALBUFSIZE)   { ULE_TYPES_H_FTAG; set(rhs); }               \
    TYPENAME(const char* rhs) : String(LOCALBUFSIZE)     { ULE_TYPES_H_FTAG; set(rhs); }               \
    TYPENAME(const TYPENAME& rhs) : String(LOCALBUFSIZE) { ULE_TYPES_H_FTAG; set(rhs); }               \
    TYPENAME&   operator=(const char* rhs)               { ULE_TYPES_H_FTAG; set(rhs); return *this; } \
    TYPENAME&   operator=(const String& rhs)             { ULE_TYPES_H_FTAG; set(rhs); return *this; } \
    TYPENAME&   operator=(const TYPENAME& rhs)           { ULE_TYPES_H_FTAG; set(rhs); return *this; } \
};

// Disable PVS-Studio warning V730: Not all members of a class are initialized inside the constructor (local_buf is not initialized and that is fine)
// -V:STR_DEFINETYPE:730

// Helper to define StringXXXf constructors
#define STR_DEFINETYPE_F(TYPENAME, TYPENAME_F)                                      \
class TYPENAME_F : public TYPENAME                                                  \
{                                                                                   \
public:                                                                             \
    TYPENAME_F(const char* fmt, ...) : TYPENAME() { ULE_TYPES_H_FTAG; va_list args; va_start(args, fmt); setfv(fmt, args); va_end(args); } \
};

#ifdef __clang__
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wunused-private-field"         // warning : private field 'local_buf' is not used
#endif

// Declaring types for common sizes here
STR_DEFINETYPE(String16, 16)
STR_DEFINETYPE(String30, 30)
STR_DEFINETYPE(String64, 64)
STR_DEFINETYPE(String128, 128)
STR_DEFINETYPE(String256, 256)
STR_DEFINETYPE(String512, 512)

// Declaring helper constructors to pass in format strings in one statement
STR_DEFINETYPE_F(String16, String16f)
STR_DEFINETYPE_F(String30, String30f)
STR_DEFINETYPE_F(String64, String64f)
STR_DEFINETYPE_F(String128, String128f)
STR_DEFINETYPE_F(String256, String256f)
STR_DEFINETYPE_F(String512, String512f)

#if STR_DEFINE_STR32
STR_DEFINETYPE(String32, 32)
STR_DEFINETYPE_F(String32, String32f)
#endif

// by default, if you use a string type with a local buffer, and append to it with something bigger than the local buffer,
// you end up realloc'ing space to fit, and this reallocation is stingy - only exactly as much as needed.
// if you are creating a string which may be repeatedly concatenated with other strings/appended to, it's better
// to do a smaller number of growing allocations along the lines of what dynamic arrays do.
// this type is the same as other string types, but if it has to reserve additional space for itself, it will do so
// eagerly, at a rate of 1.5x
#define STRINGBUFFER_DEFINETYPE(TYPENAME, LOCALBUFSIZE)                             \
class TYPENAME : public String {                                                    \
    char local_buf[LOCALBUFSIZE];                                                   \
public:                                                                             \
    TYPENAME(const char* fmt, ...) : String(LOCALBUFSIZE) { ULE_TYPES_H_FTAG; va_list args; va_start(args, fmt); setfv(fmt, args); va_end(args); } \
    TYPENAME()                     : String(LOCALBUFSIZE) { ULE_TYPES_H_FTAG; }                         \
    TYPENAME(const String& rhs)    : String(LOCALBUFSIZE) { ULE_TYPES_H_FTAG; set(rhs); }               \
    TYPENAME(const char* rhs)      : String(LOCALBUFSIZE) { ULE_TYPES_H_FTAG; set(rhs); }               \
    TYPENAME(const TYPENAME& rhs)  : String(LOCALBUFSIZE) { ULE_TYPES_H_FTAG; set(rhs); }               \
    TYPENAME& operator=(const char* rhs)                  { ULE_TYPES_H_FTAG; set(rhs); return *this; } \
    TYPENAME& operator=(const String& rhs)                { ULE_TYPES_H_FTAG; set(rhs); return *this; } \
    TYPENAME& operator=(const TYPENAME& rhs)              { ULE_TYPES_H_FTAG; set(rhs); return *this; } \
    void reserve(int new_capacity) { \
        ULE_TYPES_H_FTAG; \
        if (new_capacity <= Capacity) \
            return; \
        char* new_data; \
        if (new_capacity < LocalBufSize) { \
            new_data = (char*)this + sizeof(String); \
            new_capacity = LocalBufSize; \
        } else { \
            new_data = (char*)_stringClassAllocator->mallocate((size_t)new_capacity * sizeof(char), null); \
        } \
        strncpy(new_data, Data, (size_t)new_capacity - 1); \
        new_data[new_capacity - 1] = 0; \
        if (Owned && !is_using_local_buf()) \
            _stringClassAllocator->free(Data, null); \
        Data = new_data; \
        Capacity = new_capacity; \
        Owned = 1; \
    } \
    void reserve_discard(int new_capacity) { \
        ULE_TYPES_H_FTAG; \
        if (new_capacity <= Capacity) \
            return; \
        if (Owned && !is_using_local_buf()) \
            _stringClassAllocator->free(Data, null); \
        if (new_capacity < LocalBufSize) { \
            Data = (char*)this + sizeof(String); \
            Capacity = LocalBufSize; \
        } else { \
            while (Capacity < new_capacity) { \
                Capacity = (s32)(Capacity * 1.5f); \
                Data = (char*) _stringClassAllocator->mallocate((size_t) Capacity * sizeof(char), null); \
            } \
        } \
        Owned = 1; \
    } \
};

STRINGBUFFER_DEFINETYPE(StringBuffer512, 512)

#ifdef __clang__
#pragma clang diagnostic pop
#endif

// On some platform vsnprintf() takes va_list by reference and modifies it.
// va_copy is the 'correct' way to copy a va_list but Visual Studio prior to 2013 doesn't have it.
#ifndef va_copy
#define va_copy(dest, src) (dest = src)
#endif

//-------------------------------------------------------------------------


// https://www.fileformat.info/info/unicode/category/Zs/list.htm
/* @TODO
bool isUnicodeSpaceSeparator(char c) {
    switch (c) {
        case 0x20:
        case 0xA0:
        case 0x1680:
        case 0x2000:
        case 0x2001:
        case 0x2002:
        case 0x2003:
        case 0x2004:
        case 0x2005:
        case 0x2006:
        case 0x2007:
        case 0x2008:
        case 0x2009:
        case 0x200A:
        case 0x202F:
        case 0x205F:
        case 0x3000:
            return true;

        default:
            return false;
    }
}
*/



//struct StringBuffer {
//    u32 length;
//    u32 capacity;
//    char* data;
//
//    StringBuffer(u32 initialSize = 2048);
//    StringBuffer(const char* string);
//    ~StringBuffer();
//
//    void checkIfShouldGrow();
//    bool isEmpty() const;
//    bool isFull() const;
//    char pop();
//    u32 append(char e);
//};
////================================================================================ 
//StringBuffer::StringBuffer(u32 initialSize) {
//    ULE_TYPES_H_FTAG;
//    this->length = 0;
//    this->capacity = initialSize;
//    this->data = (char*) pMalloc(sizeof(char) * this->capacity);
//}
//
//StringBuffer::StringBuffer(const char* string) {
//    this->length = String::len(string);
//    this->capacity = this->length;
//    this->data = cpy(string, this->length);
//}
//
//StringBuffer::~StringBuffer() {
//    pFree(this->data);
//}
//
//void StringBuffer::checkIfShouldGrow() {
//    ULE_TYPES_H_FTAG;
//    if (this->isFull()) {
//        // optimal number as you approach infinite elements approaches PHI, but 1.5 sometimes works better for finite sizes
//        // more testing is probably needed
//        this->capacity = (u32) (this->capacity * 1.5);
//        this->data = (char*) pRealloc(this->data, sizeof(char) * this->capacity);
//    }
//}
//
//bool StringBuffer::isEmpty() const {
//    ULE_TYPES_H_FTAG;
//    return this->length == 0;
//}
//
//bool StringBuffer::isFull() const {
//    ULE_TYPES_H_FTAG;
//    return this->length == this->capacity;
//}
//
//char StringBuffer::pop() {
//    ULE_TYPES_H_FTAG;
//    if (this->isEmpty()) {
//        die("empty");
//    }
//
//    return this->data[--this->length];
//}
//
//u32 StringBuffer::append(char e) {
//    ULE_TYPES_H_FTAG;
//    this->checkIfShouldGrow();
//
//    this->data[this->length++] = e;
//
//    return this->length - 1;
//}

#endif