// Copyright Epic Games, Inc. All Rights Reserved.

"use strict";

import { ZenPage } from "./page.js"
import { Fetcher } from "../util/fetcher.js"

////////////////////////////////////////////////////////////////////////////////
export class Page extends ZenPage
{
	async main()
	{
		this.set_title("workspaces");

		// Workspace Service Stats
		const stats_section = this._collapsible_section("Workspace Service Stats");
		this._stats_grid = stats_section.tag().classify("grid").classify("stats-tiles");

		const stats = await new Fetcher().resource("stats", "ws").json().catch(() => null);
		if (stats) { this._render_stats(stats); }

		this.connect_stats_ws((all_stats) => {
			const s = all_stats["ws"];
			if (s) { this._render_stats(s); }
		});

		const section = this.add_section("Workspaces");
		const host    = section.tag();

		// Toolbar: refresh button
		const toolbar        = host.tag().classify("module-bulk-bar");
		this._btn_refresh    = toolbar.tag("button").classify("module-bulk-btn").inner();
		this._btn_refresh.textContent = "\u21BB Refresh";
		this._btn_refresh.addEventListener("click", () => this._do_refresh());

		// Workspace table (raw DOM — in-place row updates require stable element refs)
		const table = document.createElement("table");
		table.className = "module-table";
		const thead = document.createElement("thead");
		const hrow  = document.createElement("tr");
		for (const label of ["WORKSPACE ID", "ROOT PATH"])
		{
			const th = document.createElement("th");
			th.textContent = label;
			hrow.appendChild(th);
		}
		thead.appendChild(hrow);
		table.appendChild(thead);
		this._tbody = document.createElement("tbody");
		table.appendChild(this._tbody);
		host.inner().appendChild(table);

		// State
		this._expanded  = new Set();   // workspace ids with shares panel open
		this._row_cache = new Map();   // workspace id -> row refs, for in-place DOM updates
		this._loading   = false;

		await this._load();
	}

	async _load()
	{
		if (this._loading) { return; }
		this._loading = true;
		this._btn_refresh.disabled = true;
		try
		{
			const data       = await new Fetcher().resource("/ws/").json();
			const workspaces = data.workspaces || [];
			this._render(workspaces);
		}
		catch (e) { /* service unavailable */ }
		finally
		{
			this._loading              = false;
			this._btn_refresh.disabled = false;
		}
	}

	async _do_refresh()
	{
		if (this._loading) { return; }
		this._btn_refresh.disabled = true;
		try
		{
			await new Fetcher().resource("/ws/refresh").text();
		}
		catch (e) { /* ignore */ }
		await this._load();
	}

	_render(workspaces)
	{
		const ws_map = new Map(workspaces.map(w => [w.id, w]));

		// Remove rows for workspaces no longer present
		for (const [id, row] of this._row_cache)
		{
			if (!ws_map.has(id))
			{
				row.tr.remove();
				row.detail_tr.remove();
				this._row_cache.delete(id);
				this._expanded.delete(id);
			}
		}

		// Create or update rows, then reorder tbody to match response order.
		// appendChild on an existing node moves it, so iterating in response order
		// achieves correct ordering without touching rows already in the right position.
		for (const ws of workspaces)
		{
			const id     = ws.id     || "";
			const shares = ws.shares || [];

			let row = this._row_cache.get(id);
			if (row)
			{
				// Update in-place — preserves DOM node identity so expanded state is kept
				row.root_path_node.nodeValue = ws.root_path || "";
				row.detail_tr.style.display  = this._expanded.has(id) ? "" : "none";
				row.btn_expand.textContent   = this._expanded.has(id) ? "\u25BE" : "\u25B8";
				const shares_json = JSON.stringify(shares);
				if (shares_json !== row.shares_json)
				{
					row.shares_json = shares_json;
					this._render_shares(row.sh_tbody, shares);
				}
			}
			else
			{
				// Create new workspace row
				const tr        = document.createElement("tr");
				const detail_tr = document.createElement("tr");
				detail_tr.className    = "module-metrics-row";
				detail_tr.style.display = this._expanded.has(id) ? "" : "none";

				const btn_expand = document.createElement("button");
				btn_expand.className  = "module-expand-btn";
				btn_expand.textContent = this._expanded.has(id) ? "\u25BE" : "\u25B8";
				btn_expand.addEventListener("click", () => {
					if (this._expanded.has(id))
					{
						this._expanded.delete(id);
						detail_tr.style.display = "none";
						btn_expand.textContent  = "\u25B8";
					}
					else
					{
						this._expanded.add(id);
						detail_tr.style.display = "";
						btn_expand.textContent  = "\u25BE";
					}
				});

				const id_wrap = document.createElement("span");
				id_wrap.className = "ws-id-wrap";
				id_wrap.appendChild(btn_expand);
				id_wrap.appendChild(document.createTextNode("\u00A0" + id));
				const td_id = document.createElement("td");
				td_id.appendChild(id_wrap);
				tr.appendChild(td_id);

				const root_path_node = document.createTextNode(ws.root_path || "");
				const td_root        = document.createElement("td");
				td_root.appendChild(root_path_node);
				tr.appendChild(td_root);

				// Detail row: nested shares table
				const sh_table = document.createElement("table");
				sh_table.className = "module-table ws-share-table";
				const sh_thead = document.createElement("thead");
				const sh_hrow  = document.createElement("tr");
				for (const label of ["SHARE ID", "SHARE PATH", "ALIAS"])
				{
					const th = document.createElement("th");
					th.textContent = label;
					sh_hrow.appendChild(th);
				}
				sh_thead.appendChild(sh_hrow);
				sh_table.appendChild(sh_thead);
				const sh_tbody = document.createElement("tbody");
				sh_table.appendChild(sh_tbody);
				const detail_td   = document.createElement("td");
				detail_td.colSpan = 2;
				detail_td.className = "ws-detail-cell";
				detail_td.appendChild(sh_table);
				detail_tr.appendChild(detail_td);

				this._render_shares(sh_tbody, shares);

				row = { tr, detail_tr, root_path_node, sh_tbody, btn_expand, shares_json: JSON.stringify(shares) };
				this._row_cache.set(id, row);
			}

			this._tbody.appendChild(row.tr);
			this._tbody.appendChild(row.detail_tr);
		}
	}

	_render_stats(stats)
	{
		const grid = this._stats_grid;
		grid.inner().innerHTML = "";

		// HTTP Requests tile
		this._render_http_requests_tile(grid, stats.requests);
	}

	_render_shares(sh_tbody, shares)
	{
		sh_tbody.innerHTML = "";
		if (shares.length === 0)
		{
			const tr = document.createElement("tr");
			const td = document.createElement("td");
			td.colSpan   = 3;
			td.className = "ws-no-shares-cell";
			td.textContent   = "No shares";
			tr.appendChild(td);
			sh_tbody.appendChild(tr);
			return;
		}
		for (const share of shares)
		{
			const tr = document.createElement("tr");
			for (const text of [share.id || "", share.share_path || "", share.alias || ""])
			{
				const td = document.createElement("td");
				td.textContent   = text;
				tr.appendChild(td);
			}
			sh_tbody.appendChild(tr);
		}
	}
}