crud.js

// In-memory storage for Gantt tasks and links
// (simple demo: no DB, no ordering persistence)

let taskIdSeed = 6;
let linkIdSeed = 4;

const tasks = [
	{ id: 1, text: "Project #1", start_date: "2025-04-20 00:00:00", duration: 6, progress: 0.4, parent: 0, open: true },
	{ id: 2, text: "Task #1", start_date: "2025-04-21 00:00:00", duration: 3, progress: 0.3, parent: 1, open: true },
	{ id: 3, text: "Task #2", start_date: "2025-04-24 00:00:00", duration: 4, progress: 0.6, parent: 1, open: true },
	{ id: 4, text: "Subtask 2.1", start_date: "2025-04-24 00:00:00", duration: 2, progress: 0.2, parent: 3, open: true },
	{ id: 5, text: "Subtask 2.2", start_date: "2025-04-26 00:00:00", duration: 2, progress: 0.0, parent: 3, open: true }
];

const links = [
	{ id: 1, source: 2, target: 3, type: "0" }, // FS
	{ id: 2, source: 3, target: 4, type: "0" },
	{ id: 3, source: 4, target: 5, type: "0" }
];

function normalizeTask(payload, idOverride) {
	// Keep only fields used in this demo; assume dates arrive already formatted as "%Y-%m-%d %H:%i:%s"
	const t = {
		id: idOverride ?? payload.id,
		text: payload.text ?? "",
		start_date: payload.start_date ?? "2025-04-20 00:00:00",
		duration: Number(payload.duration ?? 1),
		progress: Number(payload.progress ?? 0),
		parent: Number(payload.parent ?? 0),
		open: payload.open !== false
	};
	return t;
}

function normalizeLink(payload, idOverride) {
	const l = {
		id: idOverride ?? payload.id,
		source: Number(payload.source),
		target: Number(payload.target),
		type: (payload.type ?? "0") + ""
	};
	return l;
}

// --- API
function getData() {
	return { tasks, links };
}

// TASKS
function insertTask(raw) {
	const id = ++taskIdSeed;
	const item = normalizeTask(raw, id);
	tasks.push(item);
	return { action: "inserted", item, tid: id};
}

function updateTask(id, raw) {
	const idx = tasks.findIndex(t => t.id == id);
	if (idx === -1) return { action: "error" };
	const updated = normalizeTask({ ...tasks[idx], ...raw }, Number(id));
	tasks[idx] = updated;
	return { action: "updated", item: updated };
}

function deleteTask(id) {
	const numId = Number(id);
	// remove task and its children (flat)
	const toRemove = new Set([numId]);
	// only one level for simplicity; enough for demo
	tasks.forEach(t => { if (t.parent === numId) toRemove.add(t.id); });
	// also remove any links connected to removed tasks
	for (let i = links.length - 1; i >= 0; i--) {
		if (toRemove.has(links[i].source) || toRemove.has(links[i].target)) {
			links.splice(i, 1);
		}
	}
	for (let i = tasks.length - 1; i >= 0; i--) {
		if (toRemove.has(tasks[i].id)) tasks.splice(i, 1);
	}
	return { action: "deleted" };
}

// LINKS
function insertLink(raw) {
	const id = ++linkIdSeed;
	const item = normalizeLink(raw, id);
	links.push(item);
	return { action: "inserted", item, tid: id};
}

function updateLink(id, raw) {
	const idx = links.findIndex(l => l.id == id);
	if (idx === -1) return { action: "error" };
	const updated = normalizeLink({ ...links[idx], ...raw }, Number(id));
	links[idx] = updated;
	return { action: "updated", item: updated };
}

function deleteLink(id) {
	const idx = links.findIndex(l => l.id == id);
	if (idx !== -1) links.splice(idx, 1);
	return { action: "deleted" };
}

module.exports = {
	getData,
	insertTask,
	updateTask,
	deleteTask,
	insertLink,
	updateLink,
	deleteLink
};