#include <world/update/world_update.h>

#include <stddef.h>
#include <stdlib.h>

u32_t       tc_promise_identifier_counter           = 0;

typedef struct
{
    u32_t                   identifier;
    tc_world_s             *world;
    
} tc_worldupdate_world_promise_s;

typedef struct
{
    u32_t                   identifier;
    tc_chunkloader_s       *chunkloader;
    
} tc_worldupdate_chunkloader_promise_s;

typedef struct
{
    u32_t                   identifier;
    tc_chunklist_s          *chunklist;
    
} tc_worldupdate_chunklist_promise_s;

tc_worldupdate_world_promise_s         *tc_worldupdate_worlds_promise_registry              = NULL;
tc_worldupdate_chunkloader_promise_s   *tc_worldupdate_chunkloader_promise_registry         = NULL;
tc_worldupdate_chunklist_promise_s     *tc_worldupdate_chunklist_promise_registry           = NULL;

#define TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE 4096

void tc_worldupdate_initialize_promises()
{
    tc_worldupdate_worlds_promise_registry          = calloc(sizeof(tc_worldupdate_world_promise_s),        TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE);
    tc_worldupdate_chunkloader_promise_registry     = calloc(sizeof(tc_worldupdate_chunkloader_promise_s),  TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE);
    tc_worldupdate_chunklist_promise_registry       = calloc(sizeof(tc_worldupdate_chunklist_promise_s),    TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE);
}



tc_promise_s tc_worldupdate_reserve_world_promise()
{
    u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_world_promise_s         *entry       = &tc_worldupdate_worlds_promise_registry[index];
        if(entry->identifier == 0)
            if(entry->world != NULL)
            {
                ++tc_promise_identifier_counter;
                tc_promise_s        promise;
                promise.identifier      = tc_promise_identifier_counter;
                entry->identifier       = promise.identifier;
                entry->world            = NULL;
                
                return promise;
            }
        
        ++index;
    }
    tc_promise_s            promise;
    promise.identifier          = 0;
    promise.issueing_tick       = 0;
    return promise;
}

tc_promise_s tc_worldupdate_reserve_chunkloader_promise()
{
    u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_chunkloader_promise_s         *entry       = &tc_worldupdate_chunkloader_promise_registry[index];
        if(entry->identifier == 0)
            if(entry->chunkloader != NULL)
            {
                ++tc_promise_identifier_counter;
                tc_promise_s        promise;
                promise.identifier      = tc_promise_identifier_counter;
                entry->identifier       = promise.identifier;
                entry->chunkloader      = NULL;
                
                return promise;
            }
        
        ++index;
    }
    tc_promise_s            promise;
    promise.identifier          = 0;
    promise.issueing_tick       = 0;
    return promise;
}

tc_promise_s tc_worldupdate_reserve_chunklist_promise()
{
    u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_chunklist_promise_s         *entry       = &tc_worldupdate_chunklist_promise_registry[index];
        if(entry->identifier == 0)
            if(entry->chunklist != NULL)
            {
                ++tc_promise_identifier_counter;
                tc_promise_s        promise;
                promise.identifier      = tc_promise_identifier_counter;
                entry->identifier       = promise.identifier;
                entry->chunklist        = NULL;
                
                return promise;
            }
        
        ++index;
    }
    tc_promise_s            promise;
    promise.identifier          = 0;
    promise.issueing_tick       = 0;
    return promise;
}



const tc_world_s * tc_worldupdate_claim_world_promise(tc_promise_s promise)
{
    u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_world_promise_s         *entry       = &tc_worldupdate_worlds_promise_registry[index];
        if(entry->identifier == promise.identifier)
            if(entry->world != NULL)
            {
                entry->identifier       = 0;
                return entry->world;
            }
        
        ++index;
    }
    return NULL;
}

const tc_chunkloader_s * tc_worldupdate_claim_chunkloader_promise(tc_promise_s promise)
{
    u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_chunkloader_promise_s   *entry       = &tc_worldupdate_chunkloader_promise_registry[index];
        if(entry->identifier == promise.identifier)
            if(entry->chunkloader != NULL)
            {
                entry->identifier       = 0;
                return entry->chunkloader;
            }
        
        ++index;
    }
    return NULL;
}

const tc_chunklist_s * tc_worldupdate_claim_chunks_promise(tc_promise_s promise)
{
    u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_chunklist_promise_s     *entry       = &tc_worldupdate_chunklist_promise_registry[index];
        if(entry->identifier == promise.identifier)
            if(entry->chunklist != NULL)
            {
                entry->identifier       = 0;
                return entry->chunklist;
            }
        
        ++index;
    }
    return NULL;
}



void tc_worldupate_set_world_promise(u32_t identifier, tc_world_s *world)
{
    u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_world_promise_s   *entry       = &tc_worldupdate_worlds_promise_registry[index];
        if(entry->identifier == identifier)
            entry->world = world;
        
        ++index;
    }
}

void tc_worldupate_set_chunkloader_promise(u32_t identifier, tc_chunkloader_s *chunkloader)
{u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_chunkloader_promise_s   *entry       = &tc_worldupdate_chunkloader_promise_registry[index];
        if(entry->identifier == identifier)
            entry->chunkloader = chunkloader;
        
        ++index;
    }
}

void tc_worldupate_set_chunklist_promise(u32_t identifier, tc_chunklist_s *chunklist)
{
    u32_t       index       = 0;
    while(index < TC_WORLDUPDATE_PROMISE_REGISTRY_SIZE)
    {
        tc_worldupdate_chunklist_promise_s   *entry       = &tc_worldupdate_chunklist_promise_registry[index];
        if(entry->identifier == identifier)
            entry->chunklist = chunklist;
        
        ++index;
    }
}