Refine project structure by adding missing configuration files and updating directory organization

internal/httpapp/app.go

@@ -0,0 +1,80 @@
+package httpapp
+
+import (
+	"fmt"
+	"html/template"
+	"net/http"
+	"path/filepath"
+	"time"
+)
+
+type Config struct {
+	Addr         string
+	TemplatesDir string
+	StaticDir    string
+}
+
+type App struct {
+	cfg  Config
+	tmpl *template.Template
+	mux  *http.ServeMux
+}
+
+func New(cfg Config) (*App, error) {
+	if cfg.TemplatesDir == "" {
+		cfg.TemplatesDir = "web/templates"
+	}
+	if cfg.StaticDir == "" {
+		cfg.StaticDir = "web/static"
+	}
+
+	tmpl, err := parseTemplates(cfg.TemplatesDir)
+	if err != nil {
+		return nil, err
+	}
+
+	a := &App{
+		cfg:  cfg,
+		tmpl: tmpl,
+		mux:  http.NewServeMux(),
+	}
+
+	a.routes()
+	return a, nil
+}
+
+func (a *App) Router() http.Handler {
+	// Wrap the mux with basic middleware chain
+	return requestID(logging(a.mux))
+}
+
+func (a *App) routes() {
+	// Static
+	fs := http.FileServer(http.Dir(a.cfg.StaticDir))
+	a.mux.Handle("/static/", http.StripPrefix("/static/", fs))
+
+	// Core pages
+	a.mux.HandleFunc("/", a.handleDashboard)
+
+	// Health & metrics
+	a.mux.HandleFunc("/healthz", a.handleHealthz)
+	a.mux.HandleFunc("/metrics", a.handleMetrics)
+}
+
+func parseTemplates(dir string) (*template.Template, error) {
+	pattern := filepath.Join(dir, "*.html")
+	files, err := filepath.Glob(pattern)
+	if err != nil {
+		return nil, err
+	}
+	if len(files) == 0 {
+		return nil, fmt.Errorf("no templates found at %s", pattern)
+	}
+
+	funcs := template.FuncMap{
+		"nowRFC3339": func() string { return time.Now().Format(time.RFC3339) },
+	}
+
+	t := template.New("root").Funcs(funcs)
+	return t.ParseFiles(files...)
+}