// SPDX-FileCopyrightText: <Alexander Marthin Klemensen stud-marthin@ruc.dk>
// SPDX-FileCopyrightText: <Ian Valentin Christensen stud-ianc@ruc.dk>
// SPDX-FileCopyrightText: <Zahed Noos zahed@ruc.dk>
// SPDX-License-Identifier: GPL-3.0-or-later

package com.example.portfolio2;

import java.util.ArrayList;

// The model handles all interactions with the database
class Model{
	MyDB db=new MyDB();

	Model(){}

	// When running the program, it clears the participation database
	void initialize() {
		clearParticipation();
	}

	// Returns the integer value of the activity's index
	int getActivityIndeks(String name) {
		if(name ==null) return -1;
		ArrayList<String> result = db.query("select indeks from activity a where name is '"+name+"';", "indeks");
		return Integer.parseInt(result.getFirst());

	}

	// Inserts the given activity into participation using the activity's index
	void addParticipation(int activityIndex) {
		db.cmd("insert into participation values(123, "+activityIndex+");");
	}

	// Returns all activity names from activities currently in participation
	ArrayList<String> getParticipation(String program) {
		return db.query("select name from participation p inner join activity a on p.indeks = a.indeks where program is '" + program + "';", "name");
	}

	// Removes all entries in the participation database
	void clearParticipation() {
		db.cmd("delete from participation");
	}

	// Returns an arraylist of activities within the given program
	ArrayList<String> selectProgram(String program) {
		return db.query("select name from activity where program is '" + program + "';", "name");
	}

	// Returns the sum of ECTS points under the given category from the student as a string
	String getSumEcts(String program){
		if(program==null)return "0";
		ArrayList<String> result = db.query("select sum(activity.ects) as total_ects,student.name from student left outer join participation on student.studid = participation.studid inner join activity on participation.indeks = activity.indeks where program is '"+program+"' group by student.studid ;", "total_ects");
		if (result.isEmpty()) return "0";
		return result.getFirst();
	}
	ArrayList<String> getAllActivities() {
		return db.query("select name from activity;", "name");
	}
}