chore: complete initial features

.gitignore

@@ -1,2 +1,3 @@
 tailwindcss
 tmp/
+bin/

Dockerfile

@@ -1,26 +1,30 @@
-FROM golang:1.22-alpine as builder
+FROM golang:1.22-alpine AS builder
 
 WORKDIR /app
 
 COPY . .
 
-RUN apk update && apk upgrade && apk add --no-cache ca-certificates git
+RUN apk update && apk upgrade && apk add --no-cache ca-certificates
 RUN update-ca-certificates
 
 RUN go install github.com/a-h/templ/cmd/templ@latest
 
+ARG GIT_TAG="unknown"
+
 RUN GO_ENABLED=0 GOOS=linux go build \
-    -ldflags "debtrecyclingcalc.com/internal/buildinfo.GitTag=$(git describe --tags)" \
+    -ldflags "-X debtrecyclingcalc.com/internal/buildinfo.GitTag=${GIT_TAG}"\
     -o ./bin/main ./cmd/
 
 FROM scratch
 
 ENV ALLOWED_ORIGIN="*"
-ENV SERVER_HOST="0.0.0.0"
+ENV SERVER_HOST="127.0.0.1"
 
 COPY --from=builder /app/bin/main ./bin/main
 COPY --from=builder /app/static ./static
 
 COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/
 
+EXPOSE 8080
+
 CMD ["./bin/main"]

Makefile

@@ -20,10 +20,3 @@ dev:
 	make templ-generate
 	go build -ldflags "-X debtrecyclingcalc.com/internal/buildinfo.GitTag=dev" \
 		-o ./tmp/main ./cmd/ && air
-
-.PHONY: build
-build:
-	make tailwind-build
-	make templ-generate
-	go build -ldflags "debtrecyclingcalc.com/internal/buildinfo.GitTag=$(git describe --tags)" \
-		-o ./bin/main ./cmd/

cmd/main.go

@@ -4,61 +4,80 @@ import (
 	"context"
 	"fmt"
 	"log"
+	"log/slog"
 	"net/http"
 	"os"
 	"os/signal"
 	"syscall"
 	"time"
 
+	"debtrecyclingcalc.com/internal/buildinfo"
 	"debtrecyclingcalc.com/internal/handlers"
 	"debtrecyclingcalc.com/internal/middleware"
 )
 
 var (
-	allowedOrigin = "*"
-	serverHost    = "127.0.0.1"
-	serverPort    = "8080"
+	allowedOrigin   = "*"
+	serverHost      = "127.0.0.1"
+	serverPort      = "8080"
+	htmxHash        = "sha384-Y7hw+L/jvKeWIRRkqWYfPcvVxHzVzn5REgzbawhxAuQGwX1XWe70vji+VSeHOThJ"
+	hyperscriptHash = "sha384-+Uth1QzYJsTjnS5SXVN3fFO4I32Y571xIuv53WJ2SA7y5/36tKU1VCutONAmg5eH"
+	echartsHash     = "sha384-Mx5lkUEQPM1pOJCwFtUICyX45KNojXbkWdYhkKUKsbv391mavbfoAmONbzkgYPzR"
 )
 
 func main() {
+	logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))
 	ctx, cancel := signal.NotifyContext(
 		context.Background(),
 		os.Interrupt,
 		syscall.SIGTERM,
 	)
 
-	// Check if the SERVER_HOST env var is set and override
+	fmt.Println("gitTag", buildinfo.GitTag)
+
+	// If the SERVER_HOST env var is set, use that
 	envHost, ok := os.LookupEnv("SERVER_HOST")
 	if ok {
 		serverHost = envHost
 	}
 
-	// Check if SH_ALLOWED_ORIGIN env var is set and override
+	// If the ALLOWED_ORIGIN env var is set, use that
 	envOrigin, ok := os.LookupEnv("ALLOWED_ORIGIN")
 	if ok {
 		allowedOrigin = envOrigin
-		fmt.Printf("Allowed origin: %s\n", allowedOrigin)
+		logger.Info("allowed origin set", "allowedOrigin", allowedOrigin)
 	}
 
 	mux := http.NewServeMux()
 
 	fileServer := http.FileServer(http.Dir("./static"))
 	mux.Handle("/static/*", http.StripPrefix("/static/", fileServer))
+	mux.Handle("/favicon.ico", fileServer)
 
 	mux.HandleFunc("/",
-		middleware.CORS(
-			http.HandlerFunc(
-				handlers.IndexHandler,
-			),
-			allowedOrigin),
+		middleware.CSPMiddleware(
+			middleware.CORS(
+				http.HandlerFunc(
+					handlers.IndexHandler,
+				),
+				allowedOrigin),
+			htmxHash,
+			hyperscriptHash,
+			echartsHash,
+		),
 	)
 
 	mux.HandleFunc("/calc",
-		middleware.CORS(
-			http.HandlerFunc(
-				handlers.CalcHandler,
-			),
-			allowedOrigin),
+		middleware.CSPMiddleware(
+			middleware.CORS(
+				http.HandlerFunc(
+					handlers.CalcHandler,
+				),
+				allowedOrigin),
+			htmxHash,
+			hyperscriptHash,
+			echartsHash,
+		),
 	)
 
 	mux.HandleFunc("/healthz", http.HandlerFunc(handlers.HealthzHandler))
@@ -70,18 +89,18 @@ func main() {
 			log.Fatal(err)
 		}
 	}()
-
-	fmt.Printf("Server available at %s\n", serveAt)
+	logger.Info("server listening", "serverHost", serverHost, "serverPort", serverPort)
 
 	// Wait for interrupt signal.
 	<-ctx.Done()
 
 	// Sleep to ensure graceful shutdown
-	fmt.Println("Server shutting down...")
-	time.Sleep(5 * time.Second)
+	sleepSeconds := 5
+	logger.Info("shutting down", "sleepSeconds", sleepSeconds)
+	time.Sleep(time.Duration(sleepSeconds) * time.Second)
 
 	// Return to default context.
 	cancel()
 
-	fmt.Println("Server stopped")
+	logger.Info("server shut down gracefully")
 }

internal/calc/calc.go

@@ -1,6 +1,7 @@
 package calc
 
 import (
+	"errors"
 	"math"
 	"strings"
 )
@@ -33,47 +34,85 @@ type DebtRecyclingData struct {
 	TotalValue            float64
 }
 
-func taxRate(salary float64, country string) float64 {
-	taxBrackets := []struct {
-		lowerBound   float64
-		upperBound   float64
-		marginalRate float64
-	}{}
-	switch strings.ToLower(country) {
-	case "au":
-		taxBrackets = []struct {
-			lowerBound   float64
-			upperBound   float64
-			marginalRate float64
-		}{
-			{0, 18200, 0},
-			{18201, 45000, 0.16},
-			{45001, 135000, 0.30},
-			{135001, 190000, 0.37},
-			{190001, math.MaxFloat64, 0.45},
-		}
-	case "nz":
-		taxBrackets = []struct {
-			lowerBound   float64
-			upperBound   float64
-			marginalRate float64
-		}{
-			{0, 14000, 0.105},
-			{14001, 48000, 0.175},
-			{48001, 70000, 0.30},
-			{70001, 180000, 0.33},
-			{180001, math.MaxFloat64, 0.39},
-		}
+type TaxBracket struct {
+	LowerBound   float64
+	UpperBound   float64
+	MarginalRate float64
+}
+
+type CountryBrackets []TaxBracket
+
+var countryBrackets = map[string]CountryBrackets{
+	"au": {
+		TaxBracket{
+			LowerBound:   0,
+			UpperBound:   18200,
+			MarginalRate: 0,
+		},
+		TaxBracket{
+			LowerBound:   18201,
+			UpperBound:   45000,
+			MarginalRate: 0.16,
+		},
+		TaxBracket{
+			LowerBound:   45001,
+			UpperBound:   135000,
+			MarginalRate: 0.30,
+		},
+		TaxBracket{
+			LowerBound:   135001,
+			UpperBound:   190000,
+			MarginalRate: 0.37,
+		},
+		TaxBracket{
+			LowerBound:   190001,
+			UpperBound:   math.MaxFloat64,
+			MarginalRate: .45,
+		},
+	},
+	"nz": {
+		TaxBracket{
+			LowerBound:   0,
+			UpperBound:   14000,
+			MarginalRate: 0.105,
+		},
+		TaxBracket{
+			LowerBound:   14001,
+			UpperBound:   48000,
+			MarginalRate: 0.175,
+		},
+		TaxBracket{
+			LowerBound:   48001,
+			UpperBound:   70000,
+			MarginalRate: 0.30,
+		},
+		TaxBracket{
+			LowerBound:   70001,
+			UpperBound:   180000,
+			MarginalRate: 0.33,
+		},
+		TaxBracket{
+			LowerBound:   180001,
+			UpperBound:   math.MaxFloat64,
+			MarginalRate: 0.39,
+		},
+	},
+}
+
+func taxRate(salary float64, country string) (float64, error) {
+	taxBrackets := countryBrackets[strings.ToLower(country)]
+	if taxBrackets == nil {
+		return 0, errors.New("unknown country")
 	}
 
 	for i := len(taxBrackets) - 1; i >= 0; i-- {
 		bracket := taxBrackets[i]
-		if salary > bracket.lowerBound {
-			return bracket.marginalRate
+		if salary > bracket.LowerBound {
+			return bracket.MarginalRate, nil
 		}
 	}
 
-	return 0
+	return 0, nil
 }
 
 func CAGR(initialValue, finalValue float64, numYears int) float64 {
@@ -83,7 +122,7 @@ func CAGR(initialValue, finalValue float64, numYears int) float64 {
 	return math.Pow(finalValue/initialValue, 1/float64(numYears)) - 1
 }
 
-func DebtRecycling(params DebtRecyclingParameters) *DebtRecyclingData {
+func DebtRecycling(params DebtRecyclingParameters) (*DebtRecyclingData, error) {
 	data := &DebtRecyclingData{}
 
 	// Pre-allocate slices with the correct size
@@ -129,7 +168,10 @@ func DebtRecycling(params DebtRecyclingParameters) *DebtRecyclingData {
 		)
 
 		// Calculate tax savings (adjusting for tax liability)
-		taxRate := taxRate((params.Salary + data.DividendReturns[year]), params.Country)
+		taxRate, err := taxRate((params.Salary + data.DividendReturns[year]), params.Country)
+		if err != nil {
+			return nil, err
+		}
 		data.TaxRefunds[year] = data.TaxDeductibleInterest[year] * (1 - taxRate)
 
 		// Accumulate tax savings
@@ -175,18 +217,5 @@ func DebtRecycling(params DebtRecyclingParameters) *DebtRecyclingData {
 	data.TotalValue = data.PortfolioValue[params.NumYears] + data.CumulativeTaxRefunds[params.NumYears-1] + data.CumulativeDividends[params.NumYears-1]
 	data.TotalInvested = params.InitialInvestment + (params.AnnualInvestment * float64(params.NumYears))
 
-	return data
-}
-
-func GeometricMean(rates []float64) float64 {
-	if len(rates) == 0 {
-		return 0
-	}
-
-	product := 1.0
-	for _, rate := range rates {
-		product *= 1 + rate
-	}
-
-	return math.Pow(product, 1/float64(len(rates))) - 1
+	return data, nil
 }