const studentsdemo = [
    { "name": "Alice", "wait": 500, "sems": [0, 2] },
    { "name": "Bob", "wait": 500, "sems": [1, 2, 3]}
];
const semsdemo = [
    { "id": 0, "wait": 4, "notes": {"Alice": 13 } },
    { "id": 1, "wait": 3, "notes": {"Bob":  6 } },
    { "id": 2, "wait": 8, "notes": {"Alice": 11, "Bob": 18 } },
    { "id": 3, "wait": 7, "notes": {"Bob": 17 } },
];

/*
getStudents <= [ "Alice", #Bob" ]
getSems("Alice") <= [ 1, 3]
getSems("Bob") <= [ 2, 3, 4]
getMarks(1) <= {"Alice": 13 }
getMarks(2) <= {"Alice": 13 }...
getMarks(3) <= {"Alice": 13 }
getMarks(4) <= {"Alice": 13 }
*/


async function do_export(api_root, formsemstre_id) {
    console.log('***************** start *****************');
    const students = await api.getStudents(api_root, formsemstre_id);
    console.log('***************** got students *****************');
    console.log(students)
    console.log('***************** seeking sems *****************');
    const student_requests = students.map((student) => {
        return api.getStudentSems(api_root, student.id);
    });
    const sems = await Promise.all(student_requests);
    debugger;
    console.log('***************** got sems *****************');
    const set_sem = new Set(sems.flat());
    console.log(set_sem)
    console.log('***************** seeking marks *****************');
    const studentsGrades = await Promise.all([...set_sem].map(sem => api.getMarks(sem)));
    debugger;
    // Expected output: "resolved"
}


const api = {
    getStudents(api_root, formsemestre_id) {
        return fetch(`${api_root}/formsemestre/${formsemestre_id}/etudiants`)
            .then(response => response.json())
    },
    getStudentSems(api_root, etudid) {
        return fetch(`${api_root}/etudiant/etudid/${etudid}/formsemestres`)
            .then(response => response.json())
    },
    getMarks(sem_id) {
        return new Promise(
            resolve => { setTimeout(resolve, semsdemo[sem_id].wait, semsdemo[sem_id].notes ); }
        )
    }
}

// let loaded_sems = [];
//
// async function doit() {
//     getStudents()
//         .then(students => {
//             return Promise.all(students.map(student =>  {
//                 api.getStudentSems(student)
//                 .then(sems_id => {
//                     sem_requests = []
//                     sems_id.forEach(sem_id => {
//                         if (typeof sem_requests[sem_id] === 'undefined') {
//                             sem_requests[sem_id](api.getMarks(sem_id));
//                         });
//                     });
//                 then(allMarks => {
//                     console.log(allMarks);
//                 });
//             });
// }

/*
		let dataSrc = "/ScoDoc/{{dept}}/api/formsemestre/{{formsemestre.id}}/etudiants/long";
        let formsemestres = [];
		fetch(dataSrc)
			.then(r => { return r.json(); })
			.then(json => {
                let etudiants = json;
                promises_etud_semestres = []
                promises_semestres = []
                etudiants.forEach((etudiant) => {
                    let url =`/ScoDoc/{{dept}}/api/etudiant/nip/${etudiant.code_nip}/formsemestres`;
                    console.log(url);
                    promises_etud_semestres.push(
                        fetch(url)
                        .then(r => { return r.json(); })
                        .then(semestre => {
                            formsemestre_id = semestre.formsemestre_id;

                        })
                    )
//                    etudiant.formsemestres_id = [];
                    fetch(url)
                    .then(r => {return r.json; })
                    .then(json => {
                        let forms = json;
                        console.log(etudiant.code_nip + "     " + forms.formsemestre_id);
//                        forms.forEach((formsem) => {
//                            if (formsem.is_apc) {
//                                etudiant.formsemestres_id.push(formsem.formsemestre_id);
//                                if (formsem.formsemestre_id in_array()) {
//                                }
//                            }
//                        });
                    });
                });
				//let releve = document.querySelector("releve-but");
				//releve.showData = json;
				// Style custom à ajouter
				// let style = document.createElement("style");
				// style.textContent = `
				//	.module>div,
				//	.dateInscription,
				//	.numerosEtudiant,
				//	.dateNaissance{
				//		display: none;
				//	}`;
				//releve.shadowRoot.appendChild(style);
			})
            .catch(error => { console.log(error)});
		// .catch(error => {
		// 	let div = document.createElement("div");
		// 	div.innerText = "Une erreur s'est produite lors du transfert des données.";
		// 	div.style.fontSize = "24px";
		// 	div.style.color = "#d93030";

		// 	let releve = document.querySelector("releve-but");
		// 	releve.after(div);
		// 	releve.remove();

		// 	throw 'Fin du script - données invalides';
		// });
*/