#include <shadow.h>
#include <context.h>
#include <stdlib.h>
#include <librr/memory.h>

MtShadowLookupTree mt_create_shadow_lookup_tree()
{
    MtShadowLookupTree lookup_tree;
    rr_memset(&lookup_tree.next[0], sizeof(MtShadow *) * 256, 0);
    return lookup_tree;
}

MtShadow * mt_lookup_shadow(MtShadowRegistry *registry, u32_t identifier)
{
    u8_t index_1 = identifier >> 24;
    u8_t index_2 = (identifier >> 16) & 0xff;
    u8_t index_3 = (identifier >> 8) & 0xff;
    u8_t index_4 = identifier & 0xff;
    MtShadowLookupLevel1 *level_1 = registry->lookup_tree.next[index_1];
    if(level_1 == NULL)
        return NULL;
    MtShadowLookupLevel2 *level_2 = level_1->next[index_2];
    if(level_2 == NULL)
        return NULL;
    MtShadowLookupLevel3 *level_3 = level_2->next[index_3];
    if(level_3 == NULL)
        return NULL;
    MtShadow *shadow = level_3->next[index_4];
    return shadow;
}

void mt_delete_shadow(MtShadowRegistry *registry, MtShadow *shadow)
{
    u32_t identifier = shadow->identifier;
    mt_unpool_shadow(shadow);

    u8_t index_1 = identifier >> 24;
    u8_t index_2 = (identifier >> 16) & 0xff;
    u8_t index_3 = (identifier >> 8) & 0xff;
    u8_t index_4 = identifier & 0xff;
    MtShadowLookupLevel1 *level_1 = registry->lookup_tree.next[index_1];
    if(level_1 == NULL)
        return;
    MtShadowLookupLevel2 *level_2 = level_1->next[index_2];
    if(level_2 == NULL)
        return;
    MtShadowLookupLevel3 *level_3 = level_2->next[index_3];
    if(level_3 == NULL)
        return;
    level_3->next[index_4] = NULL;
}

void mt_write_shadow_lookup_entry(MtShadowLookupTree *tree, MtShadow *shadow)
{
    u32_t identifier = shadow->identifier;

    u8_t index_1 = identifier >> 24;
    u8_t index_2 = (identifier >> 16) & 0xff;
    u8_t index_3 = (identifier >> 8) & 0xff;
    u8_t index_4 = identifier & 0xff;
    MtShadowLookupLevel1 *level_1 = tree->next[index_1];
    if(level_1 == NULL)
    {
        tree->next[index_1] = calloc(sizeof(MtShadowLookupLevel1), 256);
        level_1 = tree->next[index_1];
    }
    MtShadowLookupLevel2 *level_2 = level_1->next[index_2];
    if(level_2 == NULL)
    {
        level_1->next[index_1] = calloc(sizeof(MtShadowLookupLevel2), 256);
        level_2 = level_1->next[index_2];
    }
    MtShadowLookupLevel3 *level_3 = level_2->next[index_3];
    if(level_3 == NULL)
    {
        level_2->next[index_1] = calloc(sizeof(MtShadowLookupLevel3), 256);
        level_3 = level_2->next[index_3];
    }
    level_3->next[index_4] = shadow;
}

MtShadow * mt_create_shadow(MtShadowRegistry *registry)
{
    MtShadow *shadow = mt_pool_shadow(&registry->root_pool);
    shadow->identifier = registry->id_counter;
    shadow->context = registry->context_ptr;
    shadow->tag_chain_start = NULL;
    mt_write_shadow_lookup_entry(&registry->lookup_tree, shadow);
    return shadow;
}