#define DATA_PUSH_BUSY_TIMEOUT 600000

sqlite3 *g_sim_db;

void sql_exec(int blob_cnt, const void **blobs, const int *blob_sizes, void (*callback)(void *data), void *data, const char *sql_format, ...) {
    assert(sql_format);

    va_list args;
    va_start(args, sql_format);
    int sql_len = vsnprintf(NULL, 0, sql_format, args) + 1;
    char *sql_str = malloc(sql_len);
    assert(sql_str);
    va_end(args);

    va_start(args, sql_format);
    vsprintf(sql_str, sql_format, args);
    va_end(args);

    int sql_res;
    sqlite3_stmt *sql_stmt;

    sql_res = sqlite3_prepare_v2(g_sim_db, sql_str, -1, &sql_stmt, NULL);
    assert(sql_res == SQLITE_OK);
    free(sql_str);

    for (int i = 0; i < blob_cnt; ++i) {
        assert(blobs[i]);
        sql_res = sqlite3_bind_blob(sql_stmt, i + 1, blobs[i], blob_sizes[i], SQLITE_STATIC);
        assert(sql_res == SQLITE_OK);
    }

    while (true) {
        sql_res = sqlite3_step(sql_stmt);

        if (sql_res == SQLITE_ROW) {
            if (callback) {
                callback(data);
            }

            continue;
        }

        if (sql_res == SQLITE_DONE) {
            break;
        }

        log_warn("SQLite database returned error %d with message:", sql_res);
        log_warn(sqlite3_errmsg(g_sim_db));

        // Only handle SQLITE_BUSY error, in which case we retry the query.
        // Setting 'journal_mode=wal;' should help prevent busy database errors.
        if (sql_res == SQLITE_BUSY) {
            log_info("Will retry query...");
            continue;
        }

        assert(false);
    }

    sqlite3_finalize(sql_stmt);
}

void sql_open(void) {
    sqlite3_open(DATA_PUSH_PATH, &g_sim_db);
    assert(g_sim_db);

    // Install busy handler to retry transactions if DB is locked
    sqlite3_busy_timeout(g_sim_db, DATA_PUSH_BUSY_TIMEOUT);

    // Enable Write-Ahead Logging (WAL)
    // This seems to help prevent DB locks when displaying live data.
    // See: https://sqlite.org/wal.html
    sql_exec(0, NULL, NULL, NULL, NULL, "pragma journal_mode=wal;");
}

void sql_close(void) {
    assert(g_sim_db);
    sqlite3_close(g_sim_db);
}