#include "negentropy_wrapper.h"

//This is a C-wrapper for the C++ library that helps in integrating negentropy with nim code.
//TODO: Do error handling by catching exceptions

void* storage_new(const char* db_path, const char* name){
    negentropy::storage::BTreeLMDB* storage;
/* 
    auto env = lmdb::env::create();
    env.set_max_dbs(64);
    env.open(db_path, 0);

    lmdb::dbi btreeDbi;

    {
        auto txn = lmdb::txn::begin(env);
        btreeDbi = negentropy::storage::BTreeLMDB::setupDB(txn, name);
        txn.commit();
    } */
    //TODO: Finish constructor 
    //storage = new negentropy::storage::BTreeLMDB();
    return storage;
}

void* negentropy_new(void* storage, uint64_t frameSizeLimit){
    //TODO: Make these typecasts into macros??
    negentropy::storage::BTreeLMDB* lmdbStorage;
    //TODO: reinterpret cast is risky, need to use more safe type conversion.
    lmdbStorage = reinterpret_cast<negentropy::storage::BTreeLMDB*>(storage);

    Negentropy<negentropy::storage::BTreeLMDB>* ne;
    try{
    ne = new Negentropy<negentropy::storage::BTreeLMDB>(*lmdbStorage, frameSizeLimit);
    }catch(negentropy::err e){
        //TODO:Find a way to return this error
        return NULL;
    }
    return ne;
}

const char* negentropy_initiate(void* negentropy){
    Negentropy<negentropy::storage::BTreeLMDB>* ngn_inst;
    ngn_inst = reinterpret_cast<Negentropy<negentropy::storage::BTreeLMDB>*>(negentropy);

    std::string* output = new std::string();
    try {
        *output = ngn_inst->initiate();
    } catch(negentropy::err e){
        //TODO:Find a way to return this error
        return NULL;
    }
    return output->c_str();
}

void negentropy_setinitiator(void* negentropy){
    Negentropy<negentropy::storage::BTreeLMDB> *ngn_inst;
    ngn_inst = reinterpret_cast<Negentropy<negentropy::storage::BTreeLMDB>*>(negentropy);

    ngn_inst->setInitiator();

}


bool storage_insert(void* storage, uint64_t createdAt, const char* id){
    negentropy::storage::BTreeLMDB* lmdbStorage;
    lmdbStorage = reinterpret_cast<negentropy::storage::BTreeLMDB*>(storage);
    
    //TODO: Error handling. Is it required?
    //How does out of memory get handled?
    return lmdbStorage->insert(createdAt, id);
}


bool storage_erase(void* storage, uint64_t createdAt, const char* id){
    negentropy::storage::BTreeLMDB* lmdbStorage;
    lmdbStorage = reinterpret_cast<negentropy::storage::BTreeLMDB*>(storage);
    
    //TODO: Error handling
    return lmdbStorage->erase(createdAt, id);
}


const char* reconcile(void* negentropy, const char* query){
    Negentropy<negentropy::storage::BTreeLMDB> *ngn_inst;
    ngn_inst = reinterpret_cast<Negentropy<negentropy::storage::BTreeLMDB>*>(negentropy);

    std::string* output = new std::string();
    try {
        *output = ngn_inst->reconcile(std::string_view(query));
    } catch(negentropy::err e){
        //TODO:Find a way to return this error
        return NULL;
    }
    return output->c_str();
}

const char* reconcile_with_ids(void* negentropy, const char* query, const char* have_ids[], 
                                        uint64_t have_ids_len, const char* need_ids[], uint64_t need_ids_len){
    Negentropy<negentropy::storage::BTreeLMDB> *ngn_inst;
    ngn_inst = reinterpret_cast<Negentropy<negentropy::storage::BTreeLMDB>*>(negentropy);

    std::optional<std::string>* output;
    std::vector<std::string> haveIds(have_ids, have_ids+have_ids_len);

    std::vector<std::string> needIds(need_ids, need_ids+need_ids_len);

    try {
        *output = ngn_inst->reconcile(std::string_view(query), haveIds, needIds);
    } catch(negentropy::err e){
        //TODO:Find a way to return this error
        return NULL;
    }
    if (output->has_value()) {
        //TODO: Figure out diff between error and this.
        return NULL;
    }else {
        
        return output->value().c_str();
    }
}