Adding template organzing, handlers, page editing

.gitignore

@@ -0,0 +1,2 @@
+galley
+data

galley.go

@@ -1,32 +1,86 @@
 package main
 
 import (
-	"fmt"
+	"html/template"
+	"log"
+	"net/http"
 	"os"
+	"regexp"
 )
 
+// cache templates on initialization
+var templates = template.Must(template.ParseFiles("tmpl/edit.html", "tmpl/view.html"))
+
+var validPath = regexp.MustCompile("^/(edit|save|view)/([a-zA-Z0-9]+)$")
+
 func main() {
-	p1 := &Page{Title: "TestPage", Body: []byte("This is a sample page.")}
-	p1.save()
-	p2, _ := loadPage("TestPage")
-	fmt.Println(string(p2.Body))
+	http.HandleFunc("/view/", makeHandler(viewHandler))
+	http.HandleFunc("/edit/", makeHandler(editHandler))
+	http.HandleFunc("/save/", makeHandler(saveHandler))
+	log.Fatal(http.ListenAndServe(":8080", nil))
 }
 
 type Page struct {
 	Title string
-	Body []byte
+	Body  []byte
 }
 
 func (p *Page) save() error {
-	filename := p.Title + ".txt"
+	filename := "data/" + p.Title + ".txt"
 	return os.WriteFile(filename, p.Body, 0600)
 }
 
 func loadPage(title string) (*Page, error) {
-	filename := title + ".txt"
+	filename := "data/" + title + ".txt"
 	body, err := os.ReadFile(filename)
 	if err != nil {
 		return nil, err
 	}
 	return &Page{Title: title, Body: body}, nil
 }
+
+func viewHandler(w http.ResponseWriter, r *http.Request, title string) {
+	p, err := loadPage(title)
+	if err != nil {
+		http.Redirect(w, r, "/edit/"+title, http.StatusFound)
+		return
+	}
+	renderTemplate(w, "view", p)
+}
+
+func editHandler(w http.ResponseWriter, r *http.Request, title string) {
+	p, err := loadPage(title)
+	if err != nil {
+		p = &Page{Title: title}
+	}
+	renderTemplate(w, "edit", p)
+}
+
+func saveHandler(w http.ResponseWriter, r *http.Request, title string) {
+	body := r.FormValue("body")
+	p := &Page{Title: title, Body: []byte(body)}
+	err := p.save()
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+	}
+	http.Redirect(w, r, "/view/"+title, http.StatusFound)
+}
+
+func renderTemplate(w http.ResponseWriter, tmpl string, p *Page) {
+	err := templates.ExecuteTemplate(w, tmpl + ".html", p)
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+	}
+}
+
+// function that takes in and modifies a function
+func makeHandler(fn func(http.ResponseWriter, *http.Request, string)) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		m := validPath.FindStringSubmatch(r.URL.Path)
+		if m == nil {
+			http.NotFound(w, r)
+			return
+		}
+		fn(w, r, m[2])
+	}
+}

tmpl/edit.html

@@ -0,0 +1,6 @@
+<h1>Editing {{.Title}}</h1>
+
+<form action="/save/{{.Title}}" method="POST">
+<div><textarea name="body" rows="20" cols="80">{{printf "%s" .Body}}</textarea></div>
+<div><input type="submit" value="Save"></div>
+</form>

tmpl/view.html

@@ -0,0 +1,3 @@
+<h1>{{.Title}}</h1>
+<p>[<a href="/edit/{{.Title}}">edit</a>]</p>
+<div>{{printf "%s" .Body}}<div>