auth_service_c/src/db_get_user_by_id.c

#include "database.h"
#include "sql.h"
#include "user.h"

User *db_get_user_by_id(const int id) {
  User *user = nullptr;
  pthread_mutex_lock(&db_mutex);
  if (!db) {
    fprintf(stderr, "Database not initialized\n");
    pthread_mutex_unlock(&db_mutex);
    return nullptr;
  }
  sqlite3_stmt *stmt;
  int rc = sqlite3_prepare_v2(db, SELECT_USER_BY_ID_SQL, -1, &stmt, nullptr);
  if (rc != SQLITE_OK) {
    fprintf(stderr, "Cannot prepare statement: %s\n", sqlite3_errmsg(db));
    pthread_mutex_unlock(&db_mutex);
    return nullptr;
  }

  sqlite3_bind_int(stmt, 1, id);

  while ((rc = sqlite3_step(stmt)) == SQLITE_ROW) {
    int id = sqlite3_column_int(stmt, 0);
    const unsigned char *db_username = sqlite3_column_text(stmt, 1);
    const unsigned char *db_email = sqlite3_column_text(stmt, 2);
    const unsigned char *db_password = sqlite3_column_text(stmt, 3);
    const unsigned char *db_group = sqlite3_column_text(stmt, 4);
    int db_is_superuser = sqlite3_column_int(stmt, 5);
    user = new_user(id, (char *)db_username, (char *)db_password,
                    (char *)db_email, (char *)db_group, db_is_superuser);
  }

  if (rc != SQLITE_DONE) {
    fprintf(stderr, "Error reading data: %s\n", sqlite3_errmsg(db));
    free_user(user);
    sqlite3_finalize(stmt);
    pthread_mutex_unlock(&db_mutex);
    return nullptr;
  }

  pthread_mutex_unlock(&db_mutex);
  return user;
}