From 3c59c31689c3120df834dc5ece3a2b2123b34eea Mon Sep 17 00:00:00 2001
From: Finn <finn@janky.solutions>
Date: Wed, 24 Jul 2024 23:01:44 -0700
Subject: [PATCH] show logged in user in web ui

---
 README.md               |  4 +--
 web/static/main.css     | 30 +++++++++++++++++++++
 web/templates.go        | 60 +++++++++++++++++++++++++++++++++++++++--
 web/templates/base.html | 13 ++++++++-
 4 files changed, 102 insertions(+), 5 deletions(-)

diff --git a/README.md b/README.md
index 8122eea..b6b5a4e 100644
--- a/README.md
+++ b/README.md
@@ -8,9 +8,9 @@ This template is intended for use with [gonew](https://go.dev/blog/gonew), but c
 
 After you run gonew or update the package name manually, you will also want to:
 
-* search for the string `go-project-template` and replace it with the name of your project.
+* search for the string `go-project-template` and replace it with the name of your project, as that string appears in a few places other than the package name itself.
 * Rename the sample config file in the root from `go-project-template.sample.json`
-* You might want to put a human-readable project name in the `<title>` element in `httpserver/templates/base.html`
+* You might want to put a human-readable project name in `httpserver/templates/base.html`, where `go-project-template` appears multiple times.
 * Rewrite this README
 
 ## Project Usage
diff --git a/web/static/main.css b/web/static/main.css
index c5c0376..76bf2d1 100644
--- a/web/static/main.css
+++ b/web/static/main.css
@@ -16,7 +16,37 @@ html, body {
     flex-grow: 1;
 }
 
+
 header {
+    display: flex;
+    justify-content: space-between;
+    border-bottom: solid black 1px;
+    padding-bottom: 1em;
+}
+
+footer {
+    display: flex;
+    justify-content: space-between;
+}
+
+.version {
+    color: #aaa;
+    font-family: 'Courier New', Courier, monospace;
+    font-size: 8pt;
+}
+
+.brand {
     font-size: 1.5em;
     font-weight: bold;
 }
+
+.btn-login {
+    background-color: #aaa;
+    border: solid #555 1px;
+    border-radius: 0.5em;
+    padding-top: 0.25em;
+    padding-bottom: 0.25em;
+    padding-left: 0.5em;
+    padding-right: 0.5em;
+    text-decoration: none;
+}
diff --git a/web/templates.go b/web/templates.go
index 32e4c17..3023370 100644
--- a/web/templates.go
+++ b/web/templates.go
@@ -2,13 +2,18 @@ package web
 
 import (
 	"embed"
+	"errors"
 	"fmt"
 	"html/template"
 	"io"
 	"io/fs"
 
 	"git.janky.solutions/finn/go-project-template/config"
+	"git.janky.solutions/finn/go-project-template/db"
+	"github.com/gorilla/sessions"
+	pgx "github.com/jackc/pgx/v5"
 	echo "github.com/labstack/echo/v4"
+	"github.com/sirupsen/logrus"
 )
 
 var (
@@ -50,11 +55,62 @@ func init() {
 type Template struct {
 }
 
-func (t *Template) Render(w io.Writer, name string, data interface{}, c echo.Context) error {
+type templateData struct {
+	Authenticated bool
+	User          db.User
+	Version       string
+	Data          any
+}
+
+func (t *templateData) dataFromContext(c echo.Context) error {
+	sessionInterface := c.Get(contextKeySession)
+	if sessionInterface == nil {
+		return nil // no session, no data to populate
+	}
+
+	session := sessionInterface.(*sessions.Session)
+
+	userIDInterface, ok := session.Values[sessionValueAuthUser]
+	if !ok {
+		return nil
+	}
+
+	userID, ok := userIDInterface.(int32)
+	if !ok {
+		logrus.WithField("userID", userIDInterface).Warn("unexpected session error: user ID is not an int32")
+		return errors.New("user ID is not an in32")
+	}
+
+	ctx := c.Request().Context()
+	queries, conn, err := db.Get(ctx)
+	if err != nil {
+		return err
+	}
+	defer conn.Close(ctx)
+
+	user, err := queries.GetUser(ctx, userID)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			return nil
+		}
+		return err
+	}
+
+	t.Authenticated = true
+	t.User = user
+	t.Version = fmt.Sprintf("%s %s", config.BuildInfo.Main.Path, config.Version)
+
+	return nil
+}
+
+func (t *Template) Render(w io.Writer, name string, data any, c echo.Context) error {
+	td := templateData{Data: data}
+	td.dataFromContext(c)
+
 	// Why does it work like this? because go's templating system doesn't handle multiple templates extending from a common base well
 	// just doing it normally causes every template to render the same (the import form, at time of writing, probably the last template alphabetically)
 	// https://stackoverflow.com/a/69244593/21894038
 	tmpl := template.Must(allTemplates.Clone())
 	tmpl = template.Must(tmpl.ParseFS(templatesSubFS, name))
-	return tmpl.ExecuteTemplate(w, name, data)
+	return tmpl.ExecuteTemplate(w, name, td)
 }
diff --git a/web/templates/base.html b/web/templates/base.html
index 250b0e1..c809d54 100644
--- a/web/templates/base.html
+++ b/web/templates/base.html
@@ -10,11 +10,22 @@
 
 <body>
     <div id="wrapper">
+        <header>
+            <span class="brand">go-project-template</span>
+            <span class="right">
+                {{ if .Authenticated }}
+                    Signed in as <span class="username">{{ .User.Username }}</span>
+                {{ else }}
+                    <a href="/auth/begin" class="btn-login">login</a>
+                {{ end }}
+            </span>
+        </header>
         <div id="main">
 {{ block "body" .}}{{ end }}
         </div>
         <footer>
-            <code>{{ version }}</code>
+            <span></span>
+            <span class="version">{{ .Version }}</span>
         </footer>
     </div>
 </body>