/* date = June 19th 2023 9:15 pm */

#ifndef CORE_STRING_H
#define CORE_STRING_H

/////////////////////////////////////
//~ sixten: String types

struct string
{
    s64 Count;
    u8 *Data;
};

typedef string buffer;

struct string_node
{
    string String;
    string_node *Next;
    string_node *Prev;
};

struct string_list
{
    string_node *First;
    string_node *Last;
    
    s64 TotalCount;
};


//~ sixten: Char funcitons

inline b32 IsWhitespace(char C);
inline b32 IsDigit(char C);
inline b32 IsLetter(char C);


//~ sixten: String functions

//- sixten: Basic constructors

inline string MakeString(u8 *Data, s64 Count);
inline string MakeString(char *CString);
#define StrLit(String) MakeString((u8 *)String, ArrayCount(String) - 1)

//- sixten: Equality

static b32 AreEqual(string A, string B);

//- sixten: Substring

static string Substring(string String, range1_s64 Range);
static string Prefix(string String, s64 Count);
static string Suffix(string String, s64 Count);

//- sixten: Hashing

static u64 HashString(string String);

//- sixten: Searching

static s64 FirstIndexOf(string String, char Char);
static s64 LastIndexOf(string String, char Char);
static s64 FirstIndexOf(string String, string Sub);
static s64 LastIndexOf(string String, string Sub);

//- sixten: Allocation

static string PushString(memory_arena *Arena, string String);
static string PushFormatVariadic(memory_arena *Arena, char *Format, va_list Arguments);
static string PushFormat(memory_arena *Arena, char *Format, ...);
static string PushCString(memory_arena *Arena, char *String);

//- sixten: Conversion

static s64 ConvertStringToS64(string String);
static string ConvertS64ToString(memory_arena *Arena, s64 Value);
static string StringFromCodepoint(memory_arena *Arena, u32 Codepoint);

//- sixten: "C Style" strings

static s64 StringLength(char *String);


//~ sixten: String list

static void AppendString(string_list *List, string String, memory_arena *Arena);
static string JoinStringList(string_list *List, memory_arena *Arena);


//~ sixten: Unicode

struct utf8_iterator
{
    // sixten: Input
    string Data;
    s64 Index;
    
    // sixten: Output
    u32 Codepoint;
};

static utf8_iterator IterateUTF8String(string String);
static void Advance(utf8_iterator *Iter);
static b32 IsValid(utf8_iterator *Iter);

static s64 UTF8FromCodepoint(u8 *Out, u32 Codepoint);

#endif //CORE_STRING_H