using Microsoft.Data.Sqlite;
using System.Globalization;
using TimeTable.model;

namespace TimeTable.controll {
    internal static class SqliteCommands {

        public static string select = "select uid, start, end, text, time from timetable";
        private static CultureInfo ci = System.Globalization.CultureInfo.GetCultureInfo("de-de");
        private static string insertPrefix = "insert into timetable (";
        private static string insertIntermediate = ") values(";
        private static string insertPostfix = ");";

        private static string updatePrefix = "update timetable set ";
        private static string updateIntermediate = " where uid = ";
        private static string updatePostfix = ";";

        public static UidCommand InsertCmd(DateTime start) {
            string uid = Guid.NewGuid().ToString();
            return BuildInsertCommand(uid, "uid, start", "'" + uid + "','" + start.ToString() + "'");
        }

        private static UidCommand BuildInsertCommand(string uid, string fields, string values) {
            string command = insertPrefix + fields + insertIntermediate + values + insertPostfix;
            UidCommand uidCommand = new UidCommand();
            uidCommand.uid = uid;
            uidCommand.command = command;
            return uidCommand;
        }


        private static string BuildUpdateCmd(string uid, string fieldValues) {
            return updatePrefix + fieldValues + updateIntermediate + uid + updatePostfix;
        }


        public static UidCommand InsertCmd(DateTime start, string text) {
            string uid = Guid.NewGuid().ToString();
            return BuildInsertCommand(uid, "uid, start", uid + "," + start.ToString());
        }


        public static string UpdateCmdCreator(string uid, string[] keys, string[] values) {
            if (keys.Length != values.Length) {
                throw new ArgumentException();
            }

            string fieldValues = "";
            for (int i = 0; i < keys.Length; i++) {
                fieldValues += "'" + keys[i] + "' = '" + values[i] + "',";
            }

            fieldValues = fieldValues.TrimEnd(',');


            return BuildUpdateCmd(uid, fieldValues);
        }


        public static string UpdateCmd(string uid, DateTime start, DateTime end, string text) {
            string[] keys = new string[3];
            keys[0] = "uid";
            keys[1] = "start";
            keys[2] = "end";
            keys[3] = "text";
            string[] values = new string[3];
            values[0] = uid;
            values[1] = start.ToString();
            values[2] = end.ToString();
            values[3] = text;
            return UpdateCmdCreator(uid, keys, values);
        }


        public static string UpdateStartCmd(string uid, DateTime start) {
            string[] keys = new string[2];
            keys[0] = "uid";
            keys[1] = "start";
            string[] values = new string[2];
            values[0] = uid;
            values[1] = start.ToString();
            return UpdateCmdCreator(uid, keys, values);
        }
        public static string UpdateEndCmd(string uid, DateTime end) {
            string[] keys = new string[2];
            keys[0] = uid;
            keys[1] = "end";
            string[] values = new string[2];
            values[0] = uid;
            values[1] = end.ToString();
            return UpdateCmdCreator(uid, keys, values);
        }


        public static string UpdateTextCmd(string uid, string text) {
            string[] keys = new string[2];
            keys[0] = uid;
            keys[1] = "text";
            string[] values = new string[2];
            values[0] = uid;
            values[1] = text;
            return UpdateCmdCreator(uid, keys, values);
        }


        public static string UpdateStartTextCmd(string uid, DateTime start, string text) {
            string[] keys = new string[3];
            keys[0] = "uid";
            keys[1] = "start";
            keys[2] = "text";
            string[] values = new string[3];
            values[0] = uid;
            values[1] = start.ToString();
            values[2] = text;
            return UpdateCmdCreator(uid, keys, values);
        }
        public static string UpdateEndTextCmd(string uid, DateTime end, string text) {
            string[] keys = new string[3];
            keys[0] = "uid";
            keys[1] = "start";
            keys[2] = "text";
            string[] values = new string[3];
            values[0] = uid;
            values[1] = end.ToString();
            values[2] = text;
            return UpdateCmdCreator(uid, keys, values);
        }


        public static string UpdateTimeCmd(string uid, TimeSpan timespan) {
            string[] keys = new string[2];
            keys[0] = uid;
            keys[1] = "time";
            string[] values = new string[2];
            values[0] = uid;
            values[1] = timespan.ToString();
            return UpdateCmdCreator(uid, keys, values);
        }



        public static void CreateTableIfNotExists(string sqlConnection) {
            SqliteConnection con = new SqliteConnection(sqlConnection);
            con.Open();
            SqliteCommand sqliteCmd = con.CreateCommand();
            sqliteCmd.CommandText = @"SELECT name FROM sqlite_master WHERE type='table' AND name='timetable';";

            var name = sqliteCmd.ExecuteScalar();
            if (name != null && name.ToString() == "timetable") {
                return;
            }
            var cols = string.Join(" VARCHAR,", "uid, start, end, text, time");
            cols = cols + " Varchar";
            sqliteCmd.CommandText = "CREATE TABLE timetable (" + cols + ")";
            con.Open();
            sqliteCmd.ExecuteNonQuery();
            con.Close();
        }
    }
}