// Copyright Epic Games, Inc. All Rights Reserved.
// Thin wrappers around the /api/* endpoints exposed by TraceViewerService.

const API = "api/";

const JSON_HEADERS = { Accept: "application/json" };

async function getJson(path) {
	const response = await fetch(API + path, { headers: JSON_HEADERS });
	if (!response.ok) {
		throw new Error(`${path}: HTTP ${response.status}`);
	}
	return response.json();
}

export function getSession() {
	return getJson("session");
}

export function getThreads() {
	return getJson("threads");
}

export function getChannels() {
	return getJson("channels");
}

export function getScopeStats() {
	return getJson("scope-stats");
}

export function getScopeNames() {
	return getJson("scope-names");
}

export async function getTimeline(threadId, startUs, endUs, minDurUs = 0, resolution = 0, { signal } = {}) {
	const params = new URLSearchParams({
		thread: String(threadId),
		start: String(startUs),
		end: String(endUs),
	});
	if (minDurUs > 0) params.set("mindur", String(minDurUs));
	if (resolution > 0) params.set("resolution", String(resolution));
	const response = await fetch(API + "timeline?" + params.toString(), { signal, headers: JSON_HEADERS });
	if (!response.ok) {
		throw new Error(`timeline: HTTP ${response.status}`);
	}
	return response.json();
}

export async function getTimelineBatch(threadIds, startUs, endUs, minDurUs = 0, resolution = 0, { signal } = {}) {
	let url = `${API}timeline-batch?threads=${threadIds.join(",")}&start=${startUs}&end=${endUs}`;
	if (minDurUs > 0) url += `&mindur=${minDurUs}`;
	if (resolution > 0) url += `&resolution=${resolution}`;
	const response = await fetch(url, { signal, headers: JSON_HEADERS });
	if (!response.ok) {
		throw new Error(`timeline-batch: HTTP ${response.status}`);
	}
	return response.json();
}

export function getLogCategories() {
	return getJson("log-categories");
}

export function getLogs({ startUs = 0, endUs = 0xffffffff, minVerbosity = 0, category = null, limit = 5000 } = {}) {
	const params = new URLSearchParams({
		start: String(startUs),
		end: String(endUs),
		min_verbosity: String(minVerbosity),
		limit: String(limit),
	});
	if (category !== null && category !== undefined) {
		params.set("category", String(category));
	}
	return getJson("logs?" + params.toString());
}

export function getBookmarks() {
	return getJson("bookmarks");
}

export function getRegions() {
	return getJson("regions");
}

export function getCsvCategories() {
	return getJson("csv-categories");
}

export function getCsvStats() {
	return getJson("csv-stats");
}

export function getCsvSeries(statId, threadId) {
	let url = "csv-series?";
	if (statId != null) url += `stat=${statId}&`;
	if (threadId != null) url += `thread=${threadId}&`;
	return getJson(url);
}

export function getCsvEvents() {
	return getJson("csv-events");
}

export function getCsvMetadata() {
	return getJson("csv-metadata");
}

export function getCounters() {
	return getJson("counters");
}

export function getCounterSeries(id) {
	return getJson(`counter-series?id=${encodeURIComponent(id)}`);
}

export function getAllocSummary() {
	return getJson("alloc-summary");
}

export function getMemoryTimeline({ startUs = 0, endUs = 0xffffffff, maxSamples = 2000 } = {}) {
	const params = new URLSearchParams({
		start: String(startUs),
		end: String(endUs),
		max_samples: String(maxSamples),
	});
	return getJson("memory-timeline?" + params.toString());
}

export function getCallstackStats(limit = 100) {
	return getJson("callstack-stats?limit=" + encodeURIComponent(limit));
}

export function getChurnStats(limit = 100) {
	return getJson("churn-stats?limit=" + encodeURIComponent(limit));
}

export function getCallstack(callstackId) {
	return getJson("callstacks?id=" + encodeURIComponent(callstackId));
}

export function getAllocSizeHistogram() {
	return getJson("alloc-size-histogram");
}