init

internal/http/render.go

@@ -0,0 +1,78 @@
+package httpserver
+
+import (
+	"bytes"
+	"fmt"
+	"html/template"
+	"net/http"
+	"path/filepath"
+	"strings"
+)
+
+type Renderer struct {
+	templates map[string]*template.Template
+}
+
+func NewRenderer(templatesDir string) (*Renderer, error) {
+	layouts, err := filepath.Glob(filepath.Join(templatesDir, "layouts", "*.gohtml"))
+	if err != nil {
+		return nil, fmt.Errorf("find layouts: %w", err)
+	}
+
+	if len(layouts) == 0 {
+		return nil, fmt.Errorf("no layout templates found in %s", filepath.Join(templatesDir, "layouts"))
+	}
+
+	partials, err := filepath.Glob(filepath.Join(templatesDir, "partials", "*.gohtml"))
+	if err != nil {
+		return nil, fmt.Errorf("find partials: %w", err)
+	}
+
+	pages, err := filepath.Glob(filepath.Join(templatesDir, "pages", "*.gohtml"))
+	if err != nil {
+		return nil, fmt.Errorf("find pages: %w", err)
+	}
+
+	if len(pages) == 0 {
+		return nil, fmt.Errorf("no page templates found in %s", filepath.Join(templatesDir, "pages"))
+	}
+
+	renderer := &Renderer{templates: make(map[string]*template.Template, len(pages))}
+
+	for _, page := range pages {
+		files := append([]string{}, layouts...)
+		files = append(files, partials...)
+		files = append(files, page)
+
+		tmpl, err := template.ParseFiles(files...)
+		if err != nil {
+			return nil, fmt.Errorf("parse template set for %s: %w", page, err)
+		}
+
+		name := strings.TrimSuffix(filepath.Base(page), filepath.Ext(page))
+		renderer.templates[name] = tmpl
+	}
+
+	return renderer, nil
+}
+
+func (r *Renderer) Render(w http.ResponseWriter, name string, status int, data any) error {
+	tmpl, ok := r.templates[name]
+	if !ok {
+		return fmt.Errorf("unknown template %q", name)
+	}
+
+	var output bytes.Buffer
+	if err := tmpl.ExecuteTemplate(&output, "base", data); err != nil {
+		return err
+	}
+
+	w.Header().Set("Content-Type", "text/html; charset=utf-8")
+	if status <= 0 {
+		status = http.StatusOK
+	}
+	w.WriteHeader(status)
+
+	_, err := output.WriteTo(w)
+	return err
+}