#include <librr/memory.h>
#include <librr/strutil.h>
#include <stdlib.h>

bool_t rr_mem_overlap(void *block1, usz_t length1, void *block2, usz_t length2)
{
    // Make block1 always be before block2
    if(block1 > block2)
    {
        void           *block_backup            = block2;
        usz_t           length_backup           = length2;
        block2                  = block1;
        length2                 = length1;
        block1                  = block_backup;
        length1                 = length_backup;
    }
    usz_t           start1                  = (usz_t) block1;
    usz_t           start2                  = (usz_t) block2;
    usz_t           end1                    = start1 + length1;
    usz_t           end2                    = start2 + length2;

    if(end2 > start1)
    {
        if(start2 > end1) return FALSE;
        return TRUE;
    }
    return FALSE;
}

bool_t rr_memequ(void *block1, void *block2, usz_t count)
{
    u8_t           *block1_8            = block1;
    u8_t           *block2_8            = block2;
    for(usz_t index = 0; index < count; ++index)
        if(block1_8[index] != block2_8[index]) return FALSE;
    return TRUE;
}

void  rr_memset(void *destination, usz_t count, u8_t value)
{
    u8_t           *destination_8       = destination;
    for(usz_t index = 0; index < count; ++index)
        destination_8[index] = value;
}

usz_t rr_memrep(void *destination, usz_t num_bytes, void *sequence, usz_t len_sequence)
{
    if(rr_mem_overlap(destination, num_bytes, sequence, len_sequence)) return 0;
    u8_t           *destination_8       = destination;
    u8_t           *sequence_8          = sequence;
    for(usz_t index = 0; index < num_bytes; ++index)
        destination_8[index] = sequence_8[index % len_sequence];
    return (num_bytes / len_sequence)           // How many full repetitions are performed
        + ((num_bytes % len_sequence) != 0);    // One more if a partial repetiton is done
}

void rr_memcopy(void *destination, void *source, usz_t num_bytes)
{
    if(rr_mem_overlap(destination, num_bytes, source, num_bytes)) return;
    u8_t           *destination_8       = destination;
    u8_t           *source_8            = source;
    for(usz_t index = 0; index < num_bytes; ++index)
        destination_8[index]                = source_8[index];
}



rr_arena_s rr_new_arena(usz_t capacity)
{
    rr_arena_s arena;
    arena.capacity = capacity;
    arena.offset = 0;
    arena.allocation = malloc(capacity);
    return arena;
}

void rr_delete_arena(rr_arena_s *arena)
{
    if(arena->allocation == NULL) return;
    free(arena->allocation);
    arena->allocation = NULL;
}



void * rr_arena_alloc(rr_arena_s *arena, usz_t length)
{
    if((arena->offset + length) > arena->capacity)
        return NULL;

    void *block = &arena->allocation[arena->offset];
    arena->offset += length;
    return block;
}

char * rr_arena_clone_string(rr_arena_s *arena, char *string)
{
    usz_t len_string = rr_measure_string(string);
    char *cloned_string = rr_arena_alloc(arena, len_string+1);
    rr_memcopy(cloned_string, string, len_string);
    cloned_string[len_string] = 0x00;

    return cloned_string;
}