improvements

README.md

@@ -32,6 +32,7 @@ whiskr is a private, self-hosted web chat interface for interacting with AI mode
 
 ## TODO
 
+- improved custom prompts
 - settings
   - auto-retry on edit
   - ctrl+enter vs enter for sending

chat.go

@@ -19,6 +19,7 @@ type ToolCall struct {
 	Args   string  `json:"args"`
 	Result string  `json:"result,omitempty"`
 	Done   bool    `json:"done,omitempty"`
+	Cost   float64 `json:"cost,omitempty"`
 }
 
 type TextFile struct {
@@ -38,14 +39,24 @@ type Reasoning struct {
 	Tokens int    `json:"tokens"`
 }
 
+type Tools struct {
+	JSON   bool `json:"json"`
+	Search bool `json:"search"`
+}
+
+type Metadata struct {
+	Timezone string `json:"timezone"`
+	Platform string `json:"platform"`
+}
+
 type Request struct {
 	Prompt      string    `json:"prompt"`
 	Model       string    `json:"model"`
 	Temperature float64   `json:"temperature"`
 	Iterations  int64     `json:"iterations"`
-	JSON        bool      `json:"json"`
+	Tools       Tools     `json:"tools"`
-	Search      bool      `json:"search"`
 	Reasoning   Reasoning `json:"reasoning"`
+	Metadata    Metadata  `json:"metadata"`
 	Messages    []Message `json:"messages"`
 }
 
@@ -118,13 +129,13 @@ func (r *Request) Parse() (*openrouter.ChatCompletionRequest, error) {
 		}
 	}
 
-	if model.JSON && r.JSON {
+	if model.JSON && r.Tools.JSON {
 		request.ResponseFormat = &openrouter.ChatCompletionResponseFormat{
 			Type: openrouter.ChatCompletionResponseFormatTypeJSONObject,
 		}
 	}
 
-	prompt, err := BuildPrompt(r.Prompt, model)
+	prompt, err := BuildPrompt(r.Prompt, r.Metadata, model)
 	if err != nil {
 		return nil, err
 	}
@@ -133,7 +144,7 @@ func (r *Request) Parse() (*openrouter.ChatCompletionRequest, error) {
 		request.Messages = append(request.Messages, openrouter.SystemMessage(prompt))
 	}
 
-	if model.Tools && r.Search && env.Tokens.Exa != "" {
+	if model.Tools && r.Tools.Search && env.Tokens.Exa != "" {
 		request.Tools = GetSearchTools()
 		request.ToolChoice = "auto"
 
@@ -409,6 +420,10 @@ func SplitImagePairs(text string) []openrouter.ChatMessagePart {
 	)
 
 	push := func(str, end int) {
+		if str > end {
+			return
+		}
+
 		rest := text[str:end]
 
 		if rest == "" {

clean.go

@@ -5,6 +5,7 @@ import "strings"
 var cleaner = strings.NewReplacer(
 	"‑", "-",
 	"—", "-",
+	"–", "-",
 
 	"“", "\"",
 	"”", "\"",

exa.go

@@ -18,9 +18,14 @@ type ExaResult struct {
 	Summary string `json:"summary"`
 }
 
+type ExaCost struct {
+	Total float64 `json:"total"`
+}
+
 type ExaResults struct {
 	RequestID string      `json:"requestId"`
 	Results   []ExaResult `json:"results"`
+	Cost      ExaCost     `json:"costDollars"`
 }
 
 func (e *ExaResult) String() string {

prompts.go

@@ -18,6 +18,7 @@ type PromptData struct {
 	Name     string
 	Slug     string
 	Date     string
+	Platform string
 }
 
 type Prompt struct {
@@ -87,7 +88,7 @@ func LoadPrompts() ([]Prompt, error) {
 		prompt := Prompt{
 			Key:  strings.Replace(filepath.Base(path), ".txt", "", 1),
 			Name: strings.TrimSpace(string(body[:index])),
-			Text: strings.TrimSpace(string(body[:index+3])),
+			Text: strings.TrimSpace(string(body[index+3:])),
 		}
 
 		prompts = append(prompts, prompt)
@@ -110,7 +111,7 @@ func LoadPrompts() ([]Prompt, error) {
 	return prompts, nil
 }
 
-func BuildPrompt(name string, model *Model) (string, error) {
+func BuildPrompt(name string, metadata Metadata, model *Model) (string, error) {
 	if name == "" {
 		return "", nil
 	}
@@ -120,12 +121,26 @@ func BuildPrompt(name string, model *Model) (string, error) {
 		return "", fmt.Errorf("unknown prompt: %q", name)
 	}
 
+	tz := time.UTC
+
+	if metadata.Timezone != "" {
+		parsed, err := time.LoadLocation(metadata.Timezone)
+		if err == nil {
+			tz = parsed
+		}
+	}
+
+	if metadata.Platform == "" {
+		metadata.Platform = "Unknown"
+	}
+
 	var buf bytes.Buffer
 
 	err := tmpl.Execute(&buf, PromptData{
 		Name:     model.Name,
 		Slug:     model.ID,
-		Date: time.Now().Format(time.RFC1123),
+		Date:     time.Now().In(tz).Format(time.RFC1123),
+		Platform: metadata.Platform,
 	})
 
 	if err != nil {

prompts/analyst.txt

@@ -1,6 +1,6 @@
 Data Analyst
 ---
-You are {{ .Name }} ({{ .Slug }}), an expert data analyst who transforms raw data into clear, actionable insights. Today is {{ .Date }}.
+You are {{ .Name }} ({{ .Slug }}), an expert data analyst who transforms raw data into clear, actionable insights. Today is {{ .Date }} (in the user's timezone). The users platform is `{{ .Platform }}`.
 
 ## Role & Expertise
 - **Primary Role**: Data analyst with expertise in statistical analysis, pattern recognition, and business intelligence

prompts/engineer.txt

@@ -1,6 +1,6 @@
 Prompt Engineer
 ---
-You are {{ .Name }} ({{ .Slug }}), an expert prompt engineering specialist who designs, optimizes, and troubleshoots prompts for maximum AI effectiveness. Today is {{ .Date }}.
+You are {{ .Name }} ({{ .Slug }}), an expert prompt engineering specialist who designs, optimizes, and troubleshoots prompts for maximum AI effectiveness. Today is {{ .Date }} (in the user's timezone). The users platform is `{{ .Platform }}`.
 
 ## Role & Expertise
 - **Primary Role**: Senior prompt engineer with deep knowledge of LLM behavior, cognitive architectures, and optimization techniques

prompts/normal.txt

@@ -1,6 +1,6 @@
 Assistant
 ---
-You are {{ .Name }} ({{ .Slug }}), a versatile AI assistant designed to help users accomplish diverse tasks efficiently and accurately. Today is {{ .Date }}.
+You are {{ .Name }} ({{ .Slug }}), a versatile AI assistant designed to help users accomplish diverse tasks efficiently and accurately. Today is {{ .Date }} (in the user's timezone). The users platform is `{{ .Platform }}`.
 
 ## Core Identity & Approach
 - **Role**: General-purpose AI assistant with broad knowledge and problem-solving capabilities

prompts/physics.txt

@@ -1,6 +1,6 @@
 Physics Explainer
 ---
-You are {{ .Name }} ({{ .Slug }}), a physics educator who makes complex concepts accessible without sacrificing accuracy. Today is {{ .Date }}.
+You are {{ .Name }} ({{ .Slug }}), a physics educator who makes complex concepts accessible without sacrificing accuracy. Today is {{ .Date }} (in the user's timezone). The users platform is `{{ .Platform }}`.
 
 ## Role & Expertise
 - **Primary Role**: Physics educator with deep conceptual understanding and exceptional communication skills

prompts/researcher.txt

@@ -1,6 +1,6 @@
 Research Assistant
 ---
-You are {{ .Name }} ({{ .Slug }}), a methodical AI research specialist who conducts systematic information gathering and synthesis to provide comprehensive, evidence-based answers. Today is {{ .Date }}.
+You are {{ .Name }} ({{ .Slug }}), a methodical AI research specialist who conducts systematic information gathering and synthesis to provide comprehensive, evidence-based answers. Today is {{ .Date }} (in the user's timezone). The users platform is `{{ .Platform }}`.
 
 ## Role & Expertise
 - **Primary Role**: Research methodologist skilled in systematic information gathering, source evaluation, and evidence synthesis

prompts/reviewer.txt

@@ -1,6 +1,6 @@
 Code Reviewer
 ---
-You are {{ .Name }} ({{ .Slug }}), an expert code security and quality analyst specializing in production-ready code assessment. Today is {{ .Date }}.
+You are {{ .Name }} ({{ .Slug }}), an expert code security and quality analyst specializing in production-ready code assessment. Today is {{ .Date }} (in the user's timezone). The users platform is `{{ .Platform }}`.
 
 ## Role & Expertise
 - **Primary Role**: Senior code reviewer with deep expertise in security vulnerabilities, performance optimization, and maintainable code practices

prompts/scripts.txt

@@ -1,6 +1,6 @@
 Shell Scripter
 ---
-You are {{ .Name }} ({{ .Slug }}), an expert automation engineer specializing in robust shell scripting and system automation. Today is {{ .Date }}.
+You are {{ .Name }} ({{ .Slug }}), an expert automation engineer specializing in robust shell scripting and system automation. Today is {{ .Date }} (in the user's timezone). The users platform is `{{ .Platform }}`.
 
 ## Role & Expertise
 - **Primary Role**: Senior DevOps engineer and automation specialist with deep expertise in Bash, PowerShell, and cross-platform scripting

search.go

@@ -116,6 +116,8 @@ func HandleSearchWebTool(ctx context.Context, tool *ToolCall) error {
 		return nil
 	}
 
+	tool.Cost = results.Cost.Total
+
 	if len(results.Results) == 0 {
 		tool.Result = "error: no search results"
 
@@ -146,6 +148,8 @@ func HandleFetchContentsTool(ctx context.Context, tool *ToolCall) error {
 		return nil
 	}
 
+	tool.Cost = results.Cost.Total
+
 	if len(results.Results) == 0 {
 		tool.Result = "error: no search results"
 

static/css/chat.css

@@ -131,6 +131,7 @@ body:not(.loading) #loading {
 	position: absolute;
 	top: 15px;
 	right: 20px;
+	z-index: 45;
 }
 
 .notification {
@@ -347,34 +348,24 @@ body:not(.loading) #loading {
 	max-width: 800px;
 }
 
-.message .reasoning,
-.message .tool,
-.message .text {
-	display: block;
-	background: transparent;
-	padding: 10px 12px;
-	width: 100%;
-}
-
-.message .reasoning {
-	padding-top: 14px;
-}
-
 .message:not(.editing) textarea.text,
 .message.editing div.text {
 	display: none;
 }
 
-.message .reasoning,
-.message .tool,
-.message div.text {
-	background: #24273a;
-}
-
 .message textarea.text {
+	display: block;
 	background: #181926;
 	min-width: 480px;
 	min-height: 100px;
+	max-width: 100%;
+	padding: 10px 12px;
+	width: calc(700px - 24px);
+	border-radius: 2px;
+}
+
+.message.assistant textarea.text {
+	width: calc(800px - 24px);
 }
 
 .message .text .error {
@@ -394,21 +385,7 @@ body:not(.loading) #loading {
 	background: #1e2030;
 	border-radius: 6px;
 	padding: 10px 12px;
-}
+	margin-top: 16px;
-
-.message .reasoning-wrapper {
-	--height: auto;
-	height: calc(var(--height) + 20px);
-	overflow: hidden;
-	transition: 150ms;
-}
-
-.message:not(.expanded) .reasoning-wrapper {
-	height: 0;
-}
-
-.message.expanded .reasoning-text {
-	margin-top: 10px;
 }
 
 .message.has-reasoning:not(.has-text):not(.errored) div.text,
@@ -420,13 +397,30 @@ body:not(.loading) #loading {
 }
 
 .message .body {
+	position: relative;
 	border-bottom-left-radius: 6px;
 	border-bottom-right-radius: 6px;
 	overflow: hidden;
+	padding: 14px 12px;
+	display: flex;
+	flex-direction: column;
+	gap: 12px;
+	background: #24273a;
 }
 
-.message.has-reasoning .text {
+.message.collapsed .body {
-	padding-top: 4px;
+	height: 32px;
+}
+
+.message.collapsed .body::before {
+	position: absolute;
+	content: "collapsed...";
+	font-style: italic;
+	color: #939ab7;
+	font-size: 12px;
+	top: 50%;
+	left: 12px;
+	transform: translateY(-50%);
 }
 
 .tool .call,
@@ -446,7 +440,7 @@ body:not(.loading) #loading {
 	background-image: url(icons/reasoning.svg);
 	position: absolute;
 	top: -2px;
-	left: -2px;
+	left: 0px;
 	width: 20px;
 	height: 20px;
 }
@@ -459,23 +453,25 @@ body:not(.loading) #loading {
 	transition: 150ms;
 }
 
-.message.expanded .reasoning .toggle::after {
+.message .reasoning,
-	transform: rotate(180deg);
-}
-
-.message.has-tool .text {
-	padding-bottom: 4px;
-}
-
 .message .tool {
 	--height: 0px;
 	overflow: hidden;
 	transition: 150ms;
-	height: calc(90px + var(--height));
+	height: calc(40px + 16px + var(--height));
+	position: relative;
+}
+
+.message .reasoning {
+	height: calc(18px + 16px + var(--height));
+}
+
+.message .reasoning:not(.expanded) {
+	height: 18px;
 }
 
 .message .tool:not(.expanded) {
-	height: 62px;
+	height: 40px;
 }
 
 .tool .call {
@@ -505,8 +501,12 @@ body:not(.loading) #loading {
 	right: -22px;
 }
 
+.reasoning.expanded .toggle::after {
+	transform: scaleY(-100%);
+}
+
 .tool.expanded .call .name::after {
-	transform: translateY(-50%) rotate(180deg);
+	transform: translateY(-50%) scaleY(-100%);
 }
 
 .tool .call::before {
@@ -518,8 +518,19 @@ body:not(.loading) #loading {
 	width: max-content;
 }
 
-.message .tool .result {
+.tool .cost {
-	margin-top: 16px;
+	position: absolute;
+	top: 2px;
+	right: 2px;
+	font-size: 12px;
+	font-style: italic;
+	color: #a5adcb;
+	transition: 150ms opacity;
+	opacity: 0;
+}
+
+.tool:hover .cost {
+	opacity: 1;
 }
 
 .message .options {
@@ -538,9 +549,31 @@ body:not(.loading) #loading {
 	pointer-events: all;
 }
 
+.message .collapse {
+	position: relative;
+	margin-right: 14px;
+}
+
+.message .collapse::before {
+	content: "";
+	transition: 150ms;
+	position: absolute;
+	top: 0;
+	left: 0;
+}
+
+.message.collapsed .collapse::before {
+	transform: scaleY(-100%);
+}
+
+.message .collapse::after {
+	position: absolute;
+	top: 4px;
+	right: -14px;
+}
+
 .message.errored .options .copy,
 .message.errored .options .edit,
-.message.errored .options .retry,
 .message.waiting .options,
 .message.reasoning .options,
 .message.tooling .options,
@@ -780,6 +813,7 @@ select {
 	gap: 4px;
 }
 
+.message .options .collapse::after,
 #chat .option+.option::before {
 	content: "";
 	display: block;
@@ -803,6 +837,8 @@ body.loading #version,
 .message .role::before,
 .message .tag-json,
 .message .tag-search,
+.message .collapse,
+.message .collapse::before,
 .message .copy,
 .message .edit,
 .message .retry,
@@ -850,6 +886,10 @@ input.invalid {
 	border: 1px solid #ed8796;
 }
 
+.message .collapse::before {
+	background-image: url(icons/collapse.svg);
+}
+
 .pre-copy,
 .message .copy {
 	background-image: url(icons/copy.svg);

static/css/icons/collapse.svg

@@ -0,0 +1,7 @@
+<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
+<!-- Uploaded to: SVG Repo, www.svgrepo.com, Transformed by: SVG Repo Mixer Tools -->
+<svg width="800px" height="800px" viewBox="0 0 24 24" fill="none" xmlns="http://www.w3.org/2000/svg">
+
+<g id="SVGRepo_bgCarrier" stroke-width="0"/>
+
+<g id="SVGRepo_tracerCarrier" stroke-linecap="round" stroke-linejoin="round"/>

static/css/markdown.css

@@ -72,6 +72,10 @@
 	text-decoration-color: rgba(183, 189, 248, 0.6);
 }
 
+.markdown p {
+	white-space: pre-wrap;
+}
+
 .markdown img {
 	max-width: 100%;
 	border-radius: 6px;

static/js/chat.js

@@ -34,6 +34,16 @@
 		$password = document.getElementById("password"),
 		$login = document.getElementById("login");
 
+	const timezone = Intl.DateTimeFormat().resolvedOptions().timeZone || "UTC";
+
+	let platform = "";
+
+	detectPlatform().then(result => {
+		platform = result;
+
+		console.info(`Detected platform: ${platform}`);
+	});
+
 	const messages = [],
 		models = {},
 		modelList = [],
@@ -143,7 +153,6 @@
 		#error = false;
 
 		#editing = false;
-		#expanded = false;
 		#state = false;
 
 		#_diff;
@@ -159,7 +168,7 @@
 		#_tool;
 		#_statistics;
 
-		constructor(role, reasoning, text, files = []) {
+		constructor(role, reasoning, text, files = [], collapsed = false) {
 			this.#id = uid();
 			this.#role = role;
 			this.#reasoning = reasoning || "";
@@ -167,7 +176,7 @@
 
 			this.#_diff = document.createElement("div");
 
-			this.#build();
+			this.#build(collapsed);
 			this.#render();
 
 			for (const file of files) {
@@ -181,9 +190,9 @@
 			}
 		}
 
-		#build() {
+		#build(collapsed) {
 			// main message div
-			this.#_message = make("div", "message", this.#role);
+			this.#_message = make("div", "message", this.#role, collapsed ? "collapsed" : "");
 
 			// message role (wrapper)
 			const _wrapper = make("div", "role", this.#role);
@@ -224,26 +233,19 @@
 			_reasoning.appendChild(_toggle);
 
 			_toggle.addEventListener("click", () => {
-				this.#expanded = !this.#expanded;
+				_reasoning.classList.toggle("expanded");
 
-				this.#_message.classList.toggle("expanded", this.#expanded);
+				if (_reasoning.classList.contains("expanded")) {
-
-				if (this.#expanded) {
 					this.#updateReasoningHeight();
 				}
 
 				updateScrollButton();
 			});
 
-			// message reasoning (height wrapper)
-			const _height = make("div", "reasoning-wrapper");
-
-			_reasoning.appendChild(_height);
-
 			// message reasoning (content)
 			this.#_reasoning = make("div", "reasoning-text", "markdown");
 
-			_height.appendChild(this.#_reasoning);
+			_reasoning.appendChild(this.#_reasoning);
 
 			// message content
 			this.#_text = make("div", "text", "markdown");
@@ -291,6 +293,13 @@
 
 			_call.appendChild(_callArguments);
 
+			// tool call cost
+			const _callCost = make("div", "cost");
+
+			_callCost.title = "Cost of this tool call";
+
+			this.#_tool.appendChild(_callCost);
+
 			// tool call result
 			const _callResult = make("div", "result", "markdown");
 
@@ -301,6 +310,19 @@
 
 			this.#_message.appendChild(_opts);
 
+			// collapse option
+			const _optCollapse = make("button", "collapse");
+
+			_optCollapse.title = "Collapse/Expand message";
+
+			_opts.appendChild(_optCollapse);
+
+			_optCollapse.addEventListener("click", () => {
+				this.#_message.classList.toggle("collapsed");
+
+				this.#save();
+			});
+
 			// copy option
 			const _optCopy = make("button", "copy");
 
@@ -471,10 +493,11 @@
 
 			if (!only || only === "tool") {
 				if (this.#tool) {
-					const { name, args, result } = this.#tool;
+					const { name, args, result, cost } = this.#tool;
 
 					const _name = this.#_tool.querySelector(".name"),
 						_arguments = this.#_tool.querySelector(".arguments"),
+						_cost = this.#_tool.querySelector(".cost"),
 						_result = this.#_tool.querySelector(".result");
 
 					_name.title = `Show ${name} call result`;
@@ -483,6 +506,8 @@
 					_arguments.title = args;
 					_arguments.textContent = args;
 
+					_cost.textContent = cost ? `${formatMoney(cost)}` : "";
+
 					_result.innerHTML = render(result || "*processing*");
 
 					this.#_tool.setAttribute("data-tool", name);
@@ -615,6 +640,10 @@
 				data.statistics = this.#statistics;
 			}
 
+			if (this.#_message.classList.contains("collapsed") && full) {
+				data.collapsed = true;
+			}
+
 			if (!data.files?.length && !data.reasoning && !data.text && !data.tool) {
 				return false;
 			}
@@ -651,7 +680,7 @@
 				console.error(err);
 
 				if (!retrying && err.message.includes("not found")) {
-					setTimeout(this.loadGenerationData.bind(this), 750, generationID, true);
+					setTimeout(this.loadGenerationData.bind(this), 1500, generationID, true);
 				}
 			}
 		}
@@ -772,12 +801,12 @@
 				activeMessage = this;
 
 				this.#_edit.value = this.#text;
-
+				this.#_edit.style.height = "";
-				this.#_edit.style.height = `${this.#_text.offsetHeight}px`;
-				this.#_edit.style.width = `${this.#_text.offsetWidth}px`;
 
 				this.setState("editing");
 
+				this.#_edit.style.height = `${Math.max(100, this.#_edit.scrollHeight)}px`;
+
 				this.#_edit.focus();
 			} else {
 				activeMessage = null;
@@ -905,6 +934,8 @@
 			chatController.abort();
 
 			if (cancel) {
+				$chat.classList.remove("completing");
+
 				return;
 			}
 		}
@@ -949,12 +980,18 @@
 			model: $model.value,
 			temperature: temperature,
 			iterations: iterations,
+			tools: {
+				json: jsonMode,
+				search: searchTool,
+			},
 			reasoning: {
 				effort: effort,
 				tokens: tokens || 0,
 			},
-			json: jsonMode,
+			metadata: {
-			search: searchTool,
+				timezone: timezone,
+				platform: platform,
+			},
 			messages: messages.map(message => message.getData()).filter(Boolean),
 		};
 
@@ -968,7 +1005,7 @@
 			message.setState(false);
 
 			if (!aborted) {
-				setTimeout(message.loadGenerationData.bind(message), 750, generationID);
+				setTimeout(message.loadGenerationData.bind(message), 1000, generationID);
 			}
 
 			message = null;
@@ -1003,6 +1040,8 @@
 			},
 			chunk => {
 				if (chunk === "aborted") {
+					chatController = null;
+
 					finish(true);
 
 					return;
@@ -1038,6 +1077,8 @@
 						message.setTool(chunk.text);
 
 						if (chunk.text.done) {
+							totalCost += chunk.text.cost || 0;
+
 							finish();
 						}
 
@@ -1247,7 +1288,7 @@
 		}
 
 		loadValue("messages", []).forEach(message => {
-			const obj = new Message(message.role, message.reasoning, message.text, message.files || []);
+			const obj = new Message(message.role, message.reasoning, message.text, message.files || [], message.collapsed);
 
 			if (message.error) {
 				obj.showError(message.error);

static/js/lib.js

@@ -45,6 +45,8 @@ function uid() {
 }
 
 function make(tag, ...classes) {
+	classes = classes.filter(Boolean);
+
 	const el = document.createElement(tag);
 
 	if (classes.length) {
@@ -222,3 +224,94 @@ function selectFile(accept, multiple, handler, onError = false) {
 		input.click();
 	});
 }
+
+async function detectPlatform() {
+	let os, arch;
+
+	let platform = navigator.platform || "";
+
+	if (navigator.userAgentData?.getHighEntropyValues) {
+		try {
+			const data = await navigator.userAgentData.getHighEntropyValues(["platform", "architecture"]);
+
+			platform = data.platform;
+			arch = data.architecture;
+		} catch {}
+	}
+
+	const ua = navigator.userAgent || "";
+
+	// Windows
+	if (/Windows NT 10\.0/.test(ua)) os = "Windows 10/11";
+	else if (/Windows NT 6\.3/.test(ua)) os = "Windows 8.1";
+	else if (/Windows NT 6\.2/.test(ua)) os = "Windows 8";
+	else if (/Windows NT 6\.1/.test(ua)) os = "Windows 7";
+	else if (/Windows NT 6\.0/.test(ua)) os = "Windows Vista";
+	else if (/Windows NT 5\.1/.test(ua)) os = "Windows XP";
+	else if (/Windows NT 5\.0/.test(ua)) os = "Windows 2000";
+	else if (/Windows NT 4\.0/.test(ua)) os = "Windows NT 4.0";
+	else if (/Win(98|95|16)/.test(ua)) os = "Windows (legacy)";
+	else if (/Windows/.test(ua)) os = "Windows (unknown version)";
+	// Mac OS
+	else if (/Mac OS X/.test(ua)) {
+		os = "macOS";
+
+		const match = ua.match(/Mac OS X ([0-9_]+)/);
+
+		if (match) {
+			os += ` ${match[1].replace(/_/g, ".")}`;
+		} else {
+			os += " (unknown version)";
+		}
+	}
+	// Chrome OS
+	else if (/CrOS/.test(ua)) {
+		os = "Chrome OS";
+
+		const match = ua.match(/CrOS [^ ]+ ([0-9.]+)/);
+
+		if (match) {
+			os += ` ${match[1]}`;
+		}
+	}
+	// Linux (special)
+	else if (/FreeBSD/.test(ua)) os = "FreeBSD";
+	else if (/OpenBSD/.test(ua)) os = "OpenBSD";
+	else if (/NetBSD/.test(ua)) os = "NetBSD";
+	else if (/SunOS/.test(ua)) os = "Solaris";
+	// Linux (generic)
+	else if (/Linux/.test(ua)) {
+		if (/Ubuntu/i.test(ua)) os = "Ubuntu";
+		else if (/Debian/i.test(ua)) os = "Debian";
+		else if (/Fedora/i.test(ua)) os = "Fedora";
+		else if (/CentOS/i.test(ua)) os = "CentOS";
+		else if (/Red Hat/i.test(ua)) os = "Red Hat";
+		else if (/SUSE/i.test(ua)) os = "SUSE";
+		else if (/Gentoo/i.test(ua)) os = "Gentoo";
+		else if (/Arch/i.test(ua)) os = "Arch Linux";
+		else os = "Linux";
+	}
+	// Mobile
+	else if (/Android/.test(ua)) os = "Android";
+	else if (/iPhone|iPad|iPod/.test(ua)) os = "iOS";
+
+	// We still have no OS?
+	if (!os && platform) {
+		if (platform.includes("Win")) os = "Windows";
+		else if (/Mac/.test(platform)) os = "macOS";
+		else if (/Linux/.test(platform)) os = "Linux";
+		else os = platform;
+	}
+
+	// Detect architecture
+	if (!arch) {
+		if (/WOW64|Win64|x64|amd64/i.test(ua)) arch = "x64";
+		else if (/arm64|aarch64/i.test(ua)) arch = "arm64";
+		else if (/i[0-9]86|x86/i.test(ua)) arch = "x86";
+		else if (/ppc/i.test(ua)) arch = "ppc";
+		else if (/sparc/i.test(ua)) arch = "sparc";
+		else if (platform && /arm/i.test(platform)) arch = "arm";
+	}
+
+	return `${os || "Unknown OS"}${arch ? `, ${arch}` : ""}`;
+}