feat(templates): hot reloading templates

this is supposed to be mostly temporaly until a better templates
interface is made

templates/templates.go

@@ -1,39 +1,77 @@
 package templates
 
+// INFO: This will probably become a new lib in loreddev/x at some point
+
 import (
 	"embed"
 	"errors"
 	"fmt"
 	"html/template"
+	"io"
+	"io/fs"
+)
+
+var (
+	patterns  = []string{"*.html", "layouts/*.html"}
+	functions = template.FuncMap{
+		"args": func(pairs ...any) (map[string]any, error) {
+			if len(pairs)%2 != 0 {
+				return nil, errors.New("misaligned map in template arguments")
+			}
+
+			m := make(map[string]any, len(pairs)/2)
+
+			for i := 0; i < len(pairs); i += 2 {
+				key, ok := pairs[i].(string)
+				if !ok {
+					return nil, fmt.Errorf("cannot use type %T as map key", pairs[i])
+				}
+
+				m[key] = pairs[i+1]
+			}
+
+			return m, nil
+		},
+	}
 )
 
 //go:embed *.html layouts/*.html
 var embedded embed.FS
 
-var temps = template.Must(template.New("templates").Funcs(template.FuncMap{
-	"args": func(pairs ...any) (map[string]any, error) {
-		if len(pairs)%2 != 0 {
-			return nil, errors.New("misaligned map in template arguments")
-		}
-
-		m := make(map[string]any, len(pairs)/2)
-
-		for i := 0; i < len(pairs); i += 2 {
-			key, ok := pairs[i].(string)
-			if !ok {
-				return nil, fmt.Errorf("cannot use type %T as map key", pairs[i])
-			}
-
-			m[key] = pairs[i+1]
-		}
-
-		return m, nil
-	},
-}).ParseFS(embedded,
-	"*.html",
-	"layouts/*.html",
-))
+var temps = template.Must(template.New("templates").Funcs(functions).ParseFS(embedded, patterns...))
 
 func Templates() *template.Template {
-	return temps
+	return temps // TODO: Support for local templates/hot-reloading without rebuild
+}
+
+func NewHotTemplates(fsys fs.FS) *HotTemplate {
+	return &HotTemplate{
+		fs: fsys,
+	}
+}
+
+type HotTemplate struct {
+	fs       fs.FS
+	template *template.Template
+}
+
+func (t *HotTemplate) Execute(wr io.Writer, data any) error {
+	te, err := template.New("hot-templates").Funcs(functions).ParseFS(t.fs, patterns...)
+	if err != nil {
+		return err
+	}
+	return te.Execute(wr, data)
+}
+
+func (t *HotTemplate) ExecuteTemplate(wr io.Writer, name string, data any) error {
+	te, err := template.New("hot-templates").Funcs(functions).ParseFS(t.fs, patterns...)
+	if err != nil {
+		return err
+	}
+	return te.ExecuteTemplate(wr, name, data)
+}
+
+type ITemplate interface {
+	Execute(wr io.Writer, data any) error
+	ExecuteTemplate(wr io.Writer, name string, data any) error
 }