AlexsanderHamir · AlexsanderHamir · Jul 29, 2025 · Jul 29, 2025 · Jul 29, 2025
diff --git a/cli/api.go b/cli/api.go
@@ -238,8 +238,10 @@ func runSetup(_ *cobra.Command, _ []string) error {
 }
 
 var validFormats = map[string]bool{
-	"summary":  true,
-	"detailed": true,
+	"summary":       true,
+	"detailed":      true,
+	"summary-html":  true,
+	"detailed-html": true,
 }
 
 // runTrack handles the track command execution
@@ -259,12 +261,7 @@ func runTrackAuto(_ *cobra.Command, _ []string) error {
 		return nil
 	}
 
-	switch outputFormat {
-	case "summary":
-		printSummary(report)
-	case "detailed":
-		printDetailedReport(report)
-	}
+	chooseOutputFormat(report)
 
 	return nil
 }
@@ -285,11 +282,7 @@ func runTrackManual(_ *cobra.Command, _ []string) error {
 		return nil
 	}
 
-	switch outputFormat {
-	case "summary":
-		printSummary(report)
-	case "detailed":
-		printDetailedReport(report)
-	}
+	chooseOutputFormat(report)
+
 	return nil
 }
diff --git a/cli/helpers.go b/cli/helpers.go
@@ -2,15 +2,18 @@ package cli
 
 import (
 	"fmt"
+	"html/template"
 	"log/slog"
 	"math"
+	"os"
 	"sort"
 
 	"github.com/AlexsanderHamir/prof/engine/benchmark"
 	"github.com/AlexsanderHamir/prof/engine/tracker"
 	"github.com/AlexsanderHamir/prof/internal/args"
 	"github.com/AlexsanderHamir/prof/internal/config"
 	"github.com/AlexsanderHamir/prof/internal/shared"
+	"github.com/microcosm-cc/bluemonday"
 )
 
 func printConfiguration(benchArgs *args.BenchArgs, functionFilterPerBench map[string]config.FunctionFilter) {
@@ -182,3 +185,225 @@ func printDetailedReport(report *tracker.ProfileChangeReport) {
 		fmt.Print(change.Report())
 	}
 }
+
+type htmlData struct {
+	TotalFunctions int
+	Regressions    []*tracker.FunctionChangeResult
+	Improvements   []*tracker.FunctionChangeResult
+	Stable         int
+}
+
+func generateHTMLSummary(report *tracker.ProfileChangeReport, outputPath string) error {
+	var regressionList, improvementList []*tracker.FunctionChangeResult
+	var stable int
+
+	for _, change := range report.FunctionChanges {
+		switch change.ChangeType {
+		case shared.REGRESSION:
+			regressionList = append(regressionList, change)
+		case shared.IMPROVEMENT:
+			improvementList = append(improvementList, change)
+		default:
+			stable++
+		}
+	}
+
+	sort.Slice(regressionList, func(i, j int) bool {
+		return regressionList[i].FlatChangePercent > regressionList[j].FlatChangePercent
+	})
+	sort.Slice(improvementList, func(i, j int) bool {
+		return math.Abs(improvementList[i].FlatChangePercent) > math.Abs(improvementList[j].FlatChangePercent)
+	})
+
+	data := htmlData{
+		TotalFunctions: len(report.FunctionChanges),
+		Regressions:    regressionList,
+		Improvements:   improvementList,
+		Stable:         stable,
+	}
+
+	tmpl := `
+<!DOCTYPE html>
+<html>
+<head>
+	<meta charset="UTF-8">
+	<title>Performance Tracking Summary</title>
+	<style>
+		body {
+			font-family: Arial, sans-serif;
+			margin: 2rem;
+			font-size: 1.25rem; /* Increased again */
+		}
+		h2 {
+			color: #333;
+			font-size: 1.8rem; /* Bigger main heading */
+		}
+		h3 {
+			font-size: 1.5rem; /* Bigger subheading */
+		}
+		.regressions { color: red; }
+		.improvements { color: green; }
+		ul { padding-left: 1.5rem; }
+	</style>
+</head>
+<body>
+	<h2>Performance Tracking Summary</h2>
+	<p><strong>Total Functions Analyzed:</strong> {{.TotalFunctions}}</p>
+	<p><strong>Regressions:</strong> {{len .Regressions}}</p>
+	<p><strong>Improvements:</strong> {{len .Improvements}}</p>
+	<p><strong>Stable:</strong> {{.Stable}}</p>
+
+	{{if .Regressions}}
+		<h3 class="regressions">⚠️ Top Regressions (worst first):</h3>
+		<ul>
+			{{range .Regressions}}<li>{{summary .}}</li>{{end}}
+		</ul>
+	{{end}}
+
+	{{if .Improvements}}
+		<h3 class="improvements">✅ Top Improvements (best first):</h3>
+		<ul>
+			{{range .Improvements}}<li>{{summary .}}</li>{{end}}
+		</ul>
+	{{end}}
+</body>
+</html>
+`
+
+	funcMap := template.FuncMap{
+		"summary": func(fc *tracker.FunctionChangeResult) string {
+			return fc.Summary()
+		},
+	}
+
+	t, err := template.New("report").Funcs(funcMap).Parse(tmpl)
+	if err != nil {
+		return err
+	}
+
+	file, err := os.Create(outputPath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	return t.Execute(file, data)
+}
+
+type detailedHTMLData struct {
+	Total        int
+	Regressions  int
+	Improvements int
+	Stable       int
+	Changes      []*tracker.FunctionChangeResult
+}
+
+func generateDetailedHTMLReport(report *tracker.ProfileChangeReport, outputPath string) error {
+	changes := report.FunctionChanges
+
+	// Count types
+	var regressions, improvements, stable int
+	for _, change := range changes {
+		switch change.ChangeType {
+		case shared.REGRESSION:
+			regressions++
+		case shared.IMPROVEMENT:
+			improvements++
+		default:
+			stable++
+		}
+	}
+
+	// Sort: regressions → improvements → stable, each by magnitude
+	typePriority := map[string]int{
+		shared.REGRESSION:  regressionPriority,
+		shared.IMPROVEMENT: improvementPriority,
+		shared.STABLE:      stablePriority,
+	}
+
+	sort.Slice(changes, func(i, j int) bool {
+		if typePriority[changes[i].ChangeType] != typePriority[changes[j].ChangeType] {
+			return typePriority[changes[i].ChangeType] < typePriority[changes[j].ChangeType]
+		}
+		return math.Abs(changes[i].FlatChangePercent) > math.Abs(changes[j].FlatChangePercent)
+	})
+
+	data := detailedHTMLData{
+		Total:        len(changes),
+		Regressions:  regressions,
+		Improvements: improvements,
+		Stable:       stable,
+		Changes:      changes,
+	}
+
+	tmpl := `
+<!DOCTYPE html>
+<html>
+<head>
+	<meta charset="UTF-8">
+	<title>Detailed Performance Report</title>
+	<style>
+		body { font-family: monospace, sans-serif; padding: 2rem; background: #f8f8f8; }
+		h1, h2 { color: #333; }
+		.stats { margin-bottom: 1rem; font-family: sans-serif; }
+		.report-block { margin-bottom: 3rem; white-space: pre-wrap; 
+		background: #fff; padding: 1rem; border-left: 4px solid #ccc; 
+		font-size: 1.25rem; }
+	</style>
+</head>
+<body>
+	<h1>📈 Detailed Performance Report</h1>
+
+	<div class="stats">
+		<p><strong>Total functions:</strong> {{.Total}}</p>
+		<p><strong>🔴 Regressions:</strong> {{.Regressions}} | <strong>🟢 Improvements:</strong> {{.Improvements}} | <strong>⚪ Stable:</strong> {{.Stable}}</p>
+		<p><em>Report Order: Regressions (worst → best), then Improvements (best → worst), then Stable</em></p>
+	</div>
+
+	{{range .Changes}}
+		<div class="report-block">
+			<pre>{{report .}}</pre>
+		</div>
+	{{end}}
+</body>
+</html>
+`
+
+	sanitizer := bluemonday.StrictPolicy()
+	funcMap := template.FuncMap{
+		"report": func(fc *tracker.FunctionChangeResult) template.HTML {
+			safe := sanitizer.Sanitize(fc.Report())
+			return template.HTML(safe) //nolint:gosec // input is being sanatized
+		},
+	}
+
+	t, err := template.New("detailed").Funcs(funcMap).Parse(tmpl)
+	if err != nil {
+		return err
+	}
+
+	file, err := os.Create(outputPath)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	return t.Execute(file, data)
+}
+
+func chooseOutputFormat(report *tracker.ProfileChangeReport) {
+	switch outputFormat {
+	case "summary":
+		printSummary(report)
+	case "detailed":
+		printDetailedReport(report)
+	case "summary-html":
+		if err := generateHTMLSummary(report, "summary.html"); err != nil {
+			slog.Info("summary-html failed", "err", err)
+		}
+	case "detailed-html":
+		if err := generateDetailedHTMLReport(report, "detailed.html"); err != nil {
+			slog.Info("detailed-html failed", "err", err)
+		}
+	}
+}
diff --git a/engine/tracker/types.go b/engine/tracker/types.go
@@ -8,25 +8,6 @@ type ProfileChangeReport struct {
 	FunctionChanges []*FunctionChangeResult
 }
 
-type ProfileChangeSummary struct {
-	TotalFunctions    int
-	Regressions       int
-	Improvements      int
-	Stable            int
-	NewFunctions      int
-	DeletedFunctions  int
-	WorstRegression   *FunctionChangeResult // Function with biggest regression
-	BestImprovement   *FunctionChangeResult // Function with biggest improvement
-	AverageFlatChange float64
-}
-
-type ChangeMetadata struct {
-	Environment string
-	Version     string
-	TestType    string // "benchmark", "load-test", "production"
-	Tags        map[string]string
-}
-
 type FunctionChangeResult struct {
 	FunctionName      string
 	ChangeType        string // shared.REGRESSION, shred.IMPROVEMENT, shared.STABLE

diff --git a/go.mod b/go.mod
@@ -5,6 +5,10 @@ go 1.24.3
 require github.com/spf13/cobra v1.9.1
 
 require (
+	github.com/aymerick/douceur v0.2.0 // indirect
+	github.com/gorilla/css v1.0.1 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/microcosm-cc/bluemonday v1.0.27 // indirect
 	github.com/spf13/pflag v1.0.7 // indirect
+	golang.org/x/net v0.26.0 // indirect
 )
diff --git a/go.sum b/go.sum
@@ -1,11 +1,19 @@
+github.com/aymerick/douceur v0.2.0 h1:Mv+mAeH1Q+n9Fr+oyamOlAkUNPWPlA8PPGR0QAaYuPk=
+github.com/aymerick/douceur v0.2.0/go.mod h1:wlT5vV2O3h55X9m7iVYN0TBM0NH/MmbLnd30/FjWUq4=
 github.com/cpuguy83/go-md2man/v2 v2.0.6/go.mod h1:oOW0eioCTA6cOiMLiUPZOpcVxMig6NIQQ7OS05n1F4g=
+github.com/gorilla/css v1.0.1 h1:ntNaBIghp6JmvWnxbZKANoLyuXTPZ4cAMlo6RyhlbO8=
+github.com/gorilla/css v1.0.1/go.mod h1:BvnYkspnSzMmwRK+b8/xgNPLiIuNZr6vbZBTPQ2A3b0=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/microcosm-cc/bluemonday v1.0.27 h1:MpEUotklkwCSLeH+Qdx1VJgNqLlpY2KXwXFM08ygZfk=
+github.com/microcosm-cc/bluemonday v1.0.27/go.mod h1:jFi9vgW+H7c3V0lb6nR74Ib/DIB5OBs92Dimizgw2cA=
 github.com/russross/blackfriday/v2 v2.1.0/go.mod h1:+Rmxgy9KzJVeS9/2gXHxylqXiyQDYRxCVz55jmeOWTM=
 github.com/spf13/cobra v1.9.1 h1:CXSaggrXdbHK9CF+8ywj8Amf7PBRmPCOJugH954Nnlo=
 github.com/spf13/cobra v1.9.1/go.mod h1:nDyEzZ8ogv936Cinf6g1RU9MRY64Ir93oCnqb9wxYW0=
 github.com/spf13/pflag v1.0.6/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/spf13/pflag v1.0.7 h1:vN6T9TfwStFPFM5XzjsvmzZkLuaLX+HS+0SeFLRgU6M=
 github.com/spf13/pflag v1.0.7/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
+golang.org/x/net v0.26.0 h1:soB7SVo0PWrY4vPW/+ay0jKDNScG2X9wFeYlXIvJsOQ=
+golang.org/x/net v0.26.0/go.mod h1:5YKkiSynbBIh3p6iOc/vibscux0x38BZDkn8sCUPxHE=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=