/*---------------------------------------------------------
 * Copyright 2022 The Go Authors. All rights reserved.
 * Licensed under the MIT License. See LICENSE in the project root for license information.
 *--------------------------------------------------------*/

// Script for VulncheckResultViewProvider's webview.

(function () {

	// @ts-ignore
	const vscode = acquireVsCodeApi();

	const logContainer = /** @type {HTMLElement} */ (document.querySelector('.log'));
	const vulnsContainer = /** @type {HTMLElement} */ (document.querySelector('.vulns'));
	const unaffectingContainer = /** @type {HTMLElement} */ (document.querySelector('.unaffecting'));

	vulnsContainer.addEventListener('click', (event) => {
		let node = event && event.target;
		if (node?.tagName === 'A' && node.href) {
			// Ask vscode to handle link opening.
			vscode.postMessage({ type: 'open', target: node.href });
			event.preventDefault();
			event.stopPropagation();
			return;
		}
	});

	const errorContainer = document.createElement('div');
	document.body.appendChild(errorContainer);
	errorContainer.className = 'error'
	errorContainer.style.display = 'none'

	function moduleVersion(/** @type {string} */mod, /** @type {string|undefined} */ver) {
		if (ver) {
			return `<a href="https://pkg.go.dev/${mod}@${ver}">${mod}@${ver}</a>`;
		}
		return 'N/A'
	}

	function snapshotContent() {
		const res = {
			'log': logContainer.innerHTML,
			'vulns': vulnsContainer.innerHTML,
			'unaffecting': unaffectingContainer.innerHTML
		};
		return JSON.stringify(res);
	}

	/**
	 * Render the document in the webview.
	 */
	function updateContent(/** @type {string} */ text = '{}') {
		let json;
		try {
			json = JSON.parse(text);
		} catch {
			errorContainer.innerText = 'Error: Document is not valid json';
			errorContainer.style.display = '';
			return;
		}
		errorContainer.style.display = 'none';

		logContainer.innerHTML = '';
		const runLog = document.createElement('table');
		const timeinfo = (startDate, durationMillisec) => {
			if (!startDate) { return '' }
			return durationMillisec ? `${startDate} (took ${durationMillisec} msec)` : `${startDate}`;
		}

		const vulns = json.Vuln || [];
		const affecting = vulns.filter((v) => v.CallStackSummaries?.length);
		const unaffecting = vulns.filter((v) => !v.CallStackSummaries?.length);
		
		runLog.innerHTML = `
<tr><td>Dir:</td><td>${json.Dir || ''}</td></tr>
<tr><td>Pattern:</td><td>${json.Pattern || ''}</td></tr>
<tr><td>Analyzed at:</td><td>${timeinfo(json.Start, json.Duration)}</td></tr>
<tr><td>Found ${affecting?.length || 0} known vulnerabilities</td></tr>`;
		logContainer.appendChild(runLog);

		vulnsContainer.innerHTML = '';
		affecting.forEach((vuln) => {
			const element = document.createElement('div');
			element.className = 'vuln';
			vulnsContainer.appendChild(element);

			// TITLE - Vuln ID
			const title = document.createElement('h2');
			title.innerHTML = `<a href="${vuln.URL}">${vuln.ID}</a>`;
			title.className = 'vuln-title';
			element.appendChild(title);

			// DESCRIPTION - short text (aliases)
			const desc = document.createElement('p');
			desc.innerHTML = Array.isArray(vuln.Aliases) && vuln.Aliases.length ? `${vuln.Details} (${vuln.Aliases.join(', ')})` : vuln.Details;
			desc.className = 'vuln-desc';
			element.appendChild(desc);

			// DETAILS - dump of all details
			const details = document.createElement('table');
			details.className = 'vuln-details'
			details.innerHTML = `
			<tr><td>Package</td><td>${vuln.PkgPath}</td></tr>
			<tr><td>Found in Version</td><td>${moduleVersion(vuln.ModPath, vuln.CurrentVersion)}</td></tr>
			<tr><td>Fixed Version</td><td>${moduleVersion(vuln.ModPath, vuln.FixedVersion)}</td></tr>
			<tr><td>Affecting</td><td>${vuln.AffectedPkgs?.join('<br>')}</td></tr>
			`;
			element.appendChild(details);

			/* TODO: Action for module version upgrade */
			/* TODO: Explain module dependency - why am I depending on this vulnerable version? */

			// EXEMPLARS - call stacks (initially hidden)
			const examples = document.createElement('details');
			examples.innerHTML = `<summary>${vuln.CallStackSummaries?.length || 0}+ findings</summary>`;

			// Call stacks
			const callstacksContainer = document.createElement('p');
			callstacksContainer.className = 'stacks';
			vuln.CallStackSummaries?.forEach((summary, idx) => {
				const callstack = document.createElement('details');
				const s = document.createElement('summary');
				s.innerText = summary;
				callstack.appendChild(s);

				const stack = document.createElement('div');
				stack.className = 'stack';
				const cs = vuln.CallStacks[idx];
				cs.forEach((c) => {
					const p = document.createElement('p');
					const pos = c.URI ? `${c.URI}?${c.Pos.line || 0}` : '';
					p.innerHTML = pos ? `<a href="${pos}">${c.Name}</a>` : c.Name;
					stack.appendChild(p);
				});
				callstack.appendChild(stack);

				callstacksContainer.appendChild(callstack);
			})

			examples.appendChild(callstacksContainer);
			element.appendChild(examples);
		});

		unaffectingContainer.innerText = '';
		if (unaffecting.length > 0) {
			unaffectingContainer.innerHTML = '<hr></hr><p>These vulnerabilities exist in required modules, but no vulnerable symbols are used.<br>No action is required. For more information, visit <a href="https://pkg.go.dev/vuln">https://pkg.go.dev/vuln</a></p>';

			const details = document.createElement('table');
			unaffecting.forEach((vuln) => {
				const row = document.createElement('tr');
				row.className = 'vuln-details'
				row.innerHTML = `<tr><td>${vuln.ModPath}</td><td><a href="${vuln.URL}">${vuln.ID}</a></td></tr>`;
				details.appendChild(row);
			});
			unaffectingContainer.appendChild(details);
		}
	}

	// Message Passing between Extension and Webview
	//
	//  Extension sends 'update' to Webview to trigger rerendering.
	//  Webview sends 'link' to Extension to forward all link
	//     click events so the extension can handle the event.
	//
	//  Extension sends 'snapshot-request' to trigger dumping
	//     of the current DOM in the 'vulns' container.
	//  Webview sends 'snapshot-result' to the extension
	//     as the response to snapshot-request.

	// Handle messages sent from the extension to the webview
	window.addEventListener('message', event => {
		const message = event.data; // The json data that the extension sent
		switch (message.type) {
			case 'update':
				const text = message.text;

				updateContent(text);
				// Then persist state information.
				// This state is returned in the call to `vscode.getState` below when a webview is reloaded.
				vscode.setState({ text });
				return;
			// Message for testing. Returns a current DOM in a serialized format.
			case 'snapshot-request':
				const result = snapshotContent();
				vscode.postMessage({ type: 'snapshot-result', target: result });
				return;
		}
	});

	// Webviews are normally torn down when not visible and re-created when they become visible again.
	// State lets us save information across these re-loads
	const state = vscode.getState();
	if (state) {
		updateContent(state.text);
	};
	// TODO: Handle 'details' expansion info and store the state using
	// vscode.setState or retainContextWhenHidden. Currently, we are storing only
	// the document text. (see windowEventHandler)
}());