#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <uuid/uuid.h>

#include <models/controller.h>
#include <macros.h>

static void
controller_load_single(MDB_txn *mdb_txn, MDB_dbi mdb_dbi, controller_db_key key_meta, MDB_val *value)
{
    int err;
    MDB_val key;

    key.mv_size = sizeof(controller_db_key);
    key.mv_data = &key_meta;

    if((err = mdb_get(mdb_txn, mdb_dbi, &key, value)) != 0)
    {
        fprintf(stderr, "mdb_get error %s\n", mdb_strerror(err));
        exit(1);
    }
}

controller*
controller_load(MDB_env *mdb_env)
{
    int err;
    MDB_txn *mdb_txn;
    MDB_dbi mdb_dbi;
    
    controller *new_controller;

    if((err = mdb_txn_begin(mdb_env, NULL, MDB_RDONLY, &mdb_txn)) != 0)
    {
        fprintf(stderr, "mdb_txn_begin error %s\n", mdb_strerror(err));
        exit(1);
    }
    if((err = mdb_dbi_open(mdb_txn, "meta", 0, &mdb_dbi)) != 0)
    {
        switch(err)
        {
            case MDB_NOTFOUND:
                mdb_txn_abort(mdb_txn);
                new_controller =  controller_create();
                controller_save(new_controller, mdb_env);
                return new_controller;
            default:
                fprintf(stderr, "mdb_txn_begin error %s\n", mdb_strerror(err));
                exit(1);
        }
    }

    new_controller = malloc(sizeof(*new_controller));

    MDB_val value;

    controller_load_single(mdb_txn, mdb_dbi, KEY_META_UUID, &value);
    memmove(new_controller->uuid, (uuid_t*)value.mv_data, sizeof(uuid_t));

    controller_load_single(mdb_txn, mdb_dbi, KEY_META_NAME, &value);
    strncpy(new_controller->name, (char*)value.mv_data, CONTROLLER_NAME_LENGTH);
    new_controller->name[CONTROLLER_NAME_LENGTH] = '\0';

    controller_load_single(mdb_txn, mdb_dbi, KEY_META_PORT, &value);
    new_controller->port = ((uint16_t*)value.mv_data)[0];

    controller_load_single(mdb_txn, mdb_dbi, KEY_META_RELAY_COUNT, &value);
    new_controller->relay_count = ((uint8_t*)value.mv_data)[0];

    controller_debug(new_controller);

    mdb_txn_abort(mdb_txn); // transaction is read only
    
    return new_controller;
}