from AppCode.Config import DBConfig


class MatCreditHandler:

    def __init__(self):
        self.conn = DBConfig.get_db_connection()
        self.cursor = self.conn.cursor(dictionary=True)

    # --------------------------------------------------
    # FETCH ALL MAT CREDIT + UTILIZATION (For UI Display)
    # --------------------------------------------------
    def fetch_all(self):
        try:
           
           self.cursor.callproc("GetMatCredit")
           result_sets = self.cursor.stored_results()
           mat_rows = next(result_sets).fetchall()
           utilization_rows = next(result_sets).fetchall()

           return mat_rows, utilization_rows
        finally:
            self.cursor.close()
            self.conn.close()

    # --------------------------------------------------
    # SAVE / UPDATE SINGLE MAT ROW (FROM MANUAL UI)
    # --------------------------------------------------
    @staticmethod
    def save_single(data):
        conn = DBConfig.get_db_connection()
        cur = conn.cursor(dictionary=True)

        try:
            # Save / Update MAT Credit
            cur.callproc(
                "SaveOrUpdateMatCredit",
                (
                    data["financial_year"],
                    data["mat_credit"],
                     data["opening_balance"],
                    data["balance"],
                    data.get("remarks", "update on manually on mat credit from ui")
                )
            )

            mat_id = None
            for result in cur.stored_results():
                mat_id = result.fetchone()["mat_id"]

            # Save utilization rows
            for u in data.get("utilization", []):
                if float(u["amount"]) > 0:
                    cur.callproc(
                        "InsertMatUtilization",
                        (mat_id, u["year"], u["amount"])
                    )

            conn.commit()

        except Exception as e:
            conn.rollback()
            raise e
        finally:
            cur.close()
            conn.close()

    # --------------------------------------------------
    # AUTO SAVE MAT FROM ITR (MAIN LOGIC)
    # --------------------------------------------------
    @staticmethod
    def save_from_itr(year, mat_created, opening_balance, mat_utilized, remarks):
        conn = DBConfig.get_db_connection()
        cur = conn.cursor(dictionary=True)

        try:
            mat_created = float(mat_created or 0)
            opening_balance = float(mat_created or 0)
            mat_utilized = float(mat_utilized or 0)

            balance = opening_balance + mat_created - mat_utilized

            # Save / Update MAT Credit
            cur.callproc(
                "SaveOrUpdateMatCredit",
                (year, mat_created, opening_balance, balance, remarks)
            )

            mat_id = None
            for result in cur.stored_results():
                mat_id = result.fetchone()["mat_id"]

            # Save utilization only if used
            if mat_utilized > 0:
                cur.callproc(
                    "InsertMatUtilization",
                    (mat_id, year, mat_utilized)
                )

            conn.commit()

        except Exception as e:
            conn.rollback()
            raise e
        finally:
            cur.close()
            conn.close()

    # --------------------------------------------------
    # DELETE MAT CREDIT SAFELY (OPTIONAL)
    # --------------------------------------------------
    def delete_by_year(self, financial_year):
        try:
            self.cursor.execute(
                "DELETE FROM mat_credit WHERE financial_year=%s",
                (financial_year,)
            )
            self.conn.commit()
        finally:
            self.cursor.close()
            self.conn.close()

    # --------------------------------------------------
    # CLOSE CONNECTION (MANUAL USE)
    # --------------------------------------------------
    def close(self):
        if self.cursor:
            self.cursor.close()
        if self.conn:
            self.conn.close()