From bebfe994aee83e43b96b5da83f529ccf8d4d7dde Mon Sep 17 00:00:00 2001
From: Jason Streifling <jason@streifling.com>
Date: Sat, 17 Aug 2024 18:21:56 +0200
Subject: [PATCH] First implementation of firebase auth

---
 cmd/backend/config.go    |  8 +++++++
 cmd/backend/firebase.go  | 11 +++++++---
 cmd/frontend/firebase.go | 45 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 61 insertions(+), 3 deletions(-)
 create mode 100644 cmd/frontend/firebase.go

diff --git a/cmd/backend/config.go b/cmd/backend/config.go
index 02f9ffc..9ef36a6 100644
--- a/cmd/backend/config.go
+++ b/cmd/backend/config.go
@@ -17,6 +17,7 @@ type Config struct {
 	KeyFile     string
 	Link        string
 	LogFile     string
+	PDFDir      string
 	PicsDir     string
 	Port        string
 	RSSFile     string
@@ -29,6 +30,7 @@ func newConfig() *Config {
 		DBName:  "cpolis",
 		KeyFile: "/var/www/cpolis/cpolis.key",
 		LogFile: "/var/log/cpolis.log",
+		PDFDir:  "/var/www/cpolis/pdfs",
 		PicsDir: "/var/www/cpolis/pics",
 		RSSFile: "/var/www/cpolis/cpolis.rss",
 		WebDir:  "/var/www/cpolis/web",
@@ -79,6 +81,7 @@ func (c *Config) handleCliArgs() error {
 	flag.StringVar(&c.KeyFile, "key", c.KeyFile, "key file")
 	flag.StringVar(&c.Link, "link", c.Link, "Channel Link")
 	flag.StringVar(&c.LogFile, "log", c.LogFile, "log file")
+	flag.StringVar(&c.PDFDir, "pdfs", c.PDFDir, "pdf directory")
 	flag.StringVar(&c.PicsDir, "pics", c.PicsDir, "pictures directory")
 	flag.StringVar(&c.RSSFile, "rss", c.RSSFile, "RSS file")
 	flag.StringVar(&c.Title, "title", c.Title, "Channel title")
@@ -96,6 +99,11 @@ func (c *Config) handleCliArgs() error {
 		return fmt.Errorf("error finding absolute path for log file: %v", err)
 	}
 
+	c.PDFDir, err = filepath.Abs(c.PDFDir)
+	if err != nil {
+		return fmt.Errorf("error finding absolute path for pdfs dir: %v", err)
+	}
+
 	c.PicsDir, err = filepath.Abs(c.PicsDir)
 	if err != nil {
 		return fmt.Errorf("error finding absolute path for pics dir: %v", err)
diff --git a/cmd/backend/firebase.go b/cmd/backend/firebase.go
index 0b5b27e..e58e8b4 100644
--- a/cmd/backend/firebase.go
+++ b/cmd/backend/firebase.go
@@ -12,7 +12,7 @@ type Client struct {
 	*auth.Client
 }
 
-func NewApp() (*Client, error) {
+func NewClient() (*Client, error) {
 	var err error
 	client := new(Client)
 
@@ -32,8 +32,13 @@ func NewApp() (*Client, error) {
 	return client, nil
 }
 
-func (c *Client) Verify(token string) (*auth.Token, error) {
+func (c *Client) Verify(idToken string) (*auth.Token, error) {
 	ctx := context.Background()
 
-	return nil, nil
+	token, err := c.VerifyIDTokenAndCheckRevoked(ctx, idToken)
+	if err != nil {
+		return nil, err
+	}
+
+	return token, nil
 }
diff --git a/cmd/frontend/firebase.go b/cmd/frontend/firebase.go
new file mode 100644
index 0000000..1d28e1f
--- /dev/null
+++ b/cmd/frontend/firebase.go
@@ -0,0 +1,45 @@
+package frontend
+
+import (
+	"log"
+	"net/http"
+	"strings"
+
+	b "streifling.com/jason/cpolis/cmd/backend"
+)
+
+func ServePDFs(c *b.Config) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		idToken := r.Header.Get("Authorization")
+		if idToken == "" {
+			http.Error(w, "Authorization header missing", http.StatusUnauthorized)
+		}
+
+		client, err := b.NewClient()
+		if err != nil {
+			log.Println(err)
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		_, err = client.Verify(idToken)
+		if err != nil {
+			log.Println(err)
+			http.Error(w, err.Error(), http.StatusUnauthorized)
+			return
+		}
+
+		pdfIDsString := r.PathValue("ids")
+		if err != nil {
+			log.Println(err)
+			http.Error(w, err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		pdfIDs := strings.Split(pdfIDsString, ",")
+
+		for _, id := range pdfIDs {
+			http.ServeFile(w, r, id)
+		}
+	}
+}