database: support entry deletion

4 files changed, 90 insertions, 10 deletions

diff --git a/src/database-mock.ts b/src/database-mock.ts
index 4d7bf55..1056be1 100644
--- a/src/database-mock.ts
+++ b/src/database-mock.ts
@@ -16,6 +16,11 @@ class DB {
 		console.log(`Mock DB save entry ${json}`);
 		return;
 	}
+
+	async deleteEntries(entryIds: [number]) {
+		console.log(`Mock DB delete entries ${entryIds}`);
+		return;
+	}
 }
 
 async function getGraduationDb() {
diff --git a/src/database-prod.ts b/src/database-prod.ts
index 57b9974..d41e829 100644
--- a/src/database-prod.ts
+++ b/src/database-prod.ts
@@ -1,9 +1,13 @@
-import { getCourseId } from "./utils-ENV.js";
+import { assert } from "./assert.ts";
+import { getCourseId, getSesskey } from "./utils-ENV.js";
 
 const DB_TEMPLATE_LIST_HEADER = `
 <table class="table table-striped">
   <thead>
     <tr>
+      <th>ChangeId</th>
+      <th>Date</th>
+      <th>Coach</th>
       <th>Json</th>
     </tr>
   </thead>
@@ -11,6 +15,7 @@ const DB_TEMPLATE_LIST_HEADER = `
 `;
 const DB_TEMPLATE_LIST_ENTRY = `
 <tr class="db-row">
+  <td class="db-cell" data-key="changeId">##id##</td>
   <td class="db-cell" data-key="date">##timeadded##</td>
   <td class="db-cell" data-key="coach">##user##</td>
   <td class="db-cell" data-key="json">[[Json]]</td>
@@ -45,7 +50,7 @@ async function findGraduationDb() {
 			return new DB(Number(dbId));
 		}
 	}
-	console.assert(false, "Graduation DB not found");
+	assert(false, "Graduation DB not found");
 }
 
 interface DatabaseParams {
@@ -58,22 +63,56 @@ interface DatabaseEntry {
 
 class DB {
 	id: number;
+	d: Promise<number> | null = null;
 
-	constructor(id: number) {
+	constructor(id: number, d?: number) {
 		this.id = id;
+		if (typeof d !== "undefined") {
+			this.d = new Promise((resolve) => {
+				resolve(d);
+			});
+		}
 	}
 
 	async fetchEntries(params?: DatabaseParams) {
-		return loadFromDatabaseActivity(this.id, params);
+		return loadFromDatabaseActivity(this, params);
 	}
 
 	async saveEntry(json: string) {
-		return addEntryToDatabaseActivity(this.id, json);
+		return addEntryToDatabaseActivity(this, json);
+	}
+
+	async deleteEntries(entryIds: [number]) {
+		return deleteFromDatabaseActivity(await this.getD(), entryIds);
+	}
+
+	async getD() {
+		if (this.d === null) this.d = fetchDFromDatabaseActivity(this);
+		return this.d;
 	}
 }
 
-async function loadFromDatabaseActivity(id: string | number, params?: DatabaseParams) {
-	let dbUrl = `${window.location.origin}/mod/data/view.php?id=${id}&mode=list&perpage=1000`;
+const dRegex = /d=(\d+)/;
+function getDFromDbDoc(db: DB, dbDoc: Document) {
+	const urlWithD = dbDoc.querySelector<HTMLInputElement>('input[name="pageurl"]')!.value;
+	const match = dRegex.exec(urlWithD);
+	if (match === null) {
+		console.error(`d of database ${db.id} not found`);
+		return -1;
+	}
+	return Number(match[1]);
+}
+
+async function fetchDFromDatabaseActivity(db: DB): Promise<number> {
+	let dbUrl = `${window.location.origin}/mod/data/view.php?id=${db.id}`;
+	const dbRes = await fetch(encodeURI(dbUrl));
+	const dbDoc = new DOMParser().parseFromString(await dbRes.text(), "text/html");
+
+	return getDFromDbDoc(db, dbDoc);
+}
+
+async function loadFromDatabaseActivity(db: DB, params?: DatabaseParams) {
+	let dbUrl = `${window.location.origin}/mod/data/view.php?id=${db.id}&mode=list&perpage=1000`;
 	// TODO(muhq): Why does this not include entries?
 	if (typeof params !== "undefined") {
 		dbUrl += "&filter=1&advanced=1";
@@ -84,6 +123,13 @@ async function loadFromDatabaseActivity(id: string | number, params?: DatabasePa
 
 	const dbRes = await fetch(encodeURI(dbUrl));
 	const dbDoc = new DOMParser().parseFromString(await dbRes.text(), "text/html");
+
+	if (db.d === null) {
+		db.d = new Promise((resolve) => {
+			resolve(getDFromDbDoc(db, dbDoc));
+		});
+	}
+
 	let data: any[] = [];
 	dbDoc.querySelectorAll(".db-row").forEach((row) => {
 		let entry: DatabaseEntry = {};
@@ -107,9 +153,9 @@ async function getGraduationDb() {
 	return (await graduationDb)!;
 }
 
-async function addEntryToDatabaseActivity(id: number, json: string) {
+async function addEntryToDatabaseActivity(db: DB, json: string) {
 	// TODO(muhq): do not fetch the form
-	const url = `/mod/data/edit.php?id=${id}`;
+	const url = `/mod/data/edit.php?id=${db.id}`;
 	const editRes = await fetch(url);
 	const editDoc = new DOMParser().parseFromString(await editRes.text(), "text/html");
 	const form = editDoc.querySelector<HTMLFormElement>('div[role="main"] > form');
@@ -127,9 +173,29 @@ async function addEntryToDatabaseActivity(id: number, json: string) {
 
 	return await fetch("/mod/data/edit.php", {
 		method: "POST",
-		// Set the FormData instance as the request body
 		body: formData,
 	});
 }
 
+async function deleteFromDatabaseActivity(d: number, entryIds: [number]) {
+	const promises = [];
+	assert(d != -1, "DB has no valid d yet.");
+	for (const entryId of entryIds) {
+		const formData = new FormData();
+
+		formData.set("d", String(d));
+		formData.set("sesskey", getSesskey());
+		formData.set("confirm", "1");
+		formData.set("delete", String(entryId));
+
+		promises.push(
+			fetch("/mod/data/view.php", {
+				method: "POST",
+				body: formData,
+			}),
+		);
+	}
+	return Promise.all(promises);
+}
+
 export { DB, DatabaseEntry, DatabaseParams, getGraduationDb };
diff --git a/src/utils-mock.js b/src/utils-mock.js
index ab4bbed..7ee3779 100644
--- a/src/utils-mock.js
+++ b/src/utils-mock.js
@@ -42,6 +42,10 @@ export function getCourseId() {
 	return "1337";
 }
 
+export function getSesskey() {
+	return "sesskey";
+}
+
 export function getCourseParticipantsUrl() {
 	console.error("Try to get mocked participations URL");
 	return "";
diff --git a/src/utils-prod.js b/src/utils-prod.js
index 94d724a..6b274d8 100644
--- a/src/utils-prod.js
+++ b/src/utils-prod.js
@@ -40,6 +40,11 @@ export function getCourseId() {
 	return String(M.cfg.courseId);
 }
 
+export function getSesskey() {
+	// M is exported by Moodle
+	return String(M.cfg.sesskey);
+}
+
 export function getCourseParticipantsUrl() {
 	return `https://lernplattform.bycs.de/user/index.php?id=${getCourseId()}&perpage=5000`;
 }