From a826f1918eb73d611b5b81a8546a3d76ecb8c932 Mon Sep 17 00:00:00 2001
From: Ben Visness <bvisness@gmail.com>
Date: Thu, 4 May 2023 23:46:31 -0500
Subject: [PATCH] Use Discord avatars as HMN avatars

---
 src/discord/message_handling.go |  9 ++++---
 src/website/discord.go          | 45 ++++++++++++++++++++++++++++++---
 2 files changed, 47 insertions(+), 7 deletions(-)

diff --git a/src/discord/message_handling.go b/src/discord/message_handling.go
index cfd9df1..6cbc2da 100644
--- a/src/discord/message_handling.go
+++ b/src/discord/message_handling.go
@@ -431,7 +431,7 @@ var discordDownloadClient = &http.Client{
 
 type DiscordResourceBadStatusCode error
 
-func downloadDiscordResource(ctx context.Context, url string) ([]byte, string, error) {
+func DownloadDiscordResource(ctx context.Context, url string) ([]byte, string, error) {
 	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
 	if err != nil {
 		return nil, "", oops.New(err, "failed to make Discord download request")
@@ -491,7 +491,7 @@ func saveAttachment(
 		height = *attachment.Height
 	}
 
-	content, _, err := downloadDiscordResource(ctx, attachment.Url)
+	content, _, err := DownloadDiscordResource(ctx, attachment.Url)
 	if err != nil {
 		return nil, oops.New(err, "failed to download Discord attachment")
 	}
@@ -561,7 +561,7 @@ func saveEmbed(
 	}
 
 	maybeSaveImageish := func(i EmbedImageish, contentTypeCheck func(string) bool) (*uuid.UUID, error) {
-		content, contentType, err := downloadDiscordResource(ctx, *i.Url)
+		content, contentType, err := DownloadDiscordResource(ctx, *i.Url)
 		if err != nil {
 			var statusError DiscordResourceBadStatusCode
 			if errors.As(err, &statusError) {
@@ -838,7 +838,8 @@ func HandleSnippetForInternedMessage(ctx context.Context, dbConn db.ConnOrTx, in
 }
 
 // TODO(asaf): I believe this will also match https://example.com?hello=1&whatever=5
-//             Probably need to add word boundaries.
+//
+//	Probably need to add word boundaries.
 var REDiscordTag = regexp.MustCompile(`&([a-zA-Z0-9]+(-[a-zA-Z0-9]+)*)`)
 
 func getDiscordTags(content string) []string {
diff --git a/src/website/discord.go b/src/website/discord.go
index 7abd9d5..1ecab4c 100644
--- a/src/website/discord.go
+++ b/src/website/discord.go
@@ -1,12 +1,14 @@
 package website
 
 import (
+	"context"
 	"errors"
 	"fmt"
 	"net/http"
 	"strings"
 	"time"
 
+	"git.handmade.network/hmn/hmn/src/assets"
 	"git.handmade.network/hmn/hmn/src/config"
 	"git.handmade.network/hmn/hmn/src/db"
 	"git.handmade.network/hmn/hmn/src/discord"
@@ -14,6 +16,7 @@ import (
 	"git.handmade.network/hmn/hmn/src/models"
 	"git.handmade.network/hmn/hmn/src/oops"
 	"git.handmade.network/hmn/hmn/src/utils"
+	"github.com/google/uuid"
 )
 
 // This callback handles Discord account linking whether the user is signed in
@@ -194,16 +197,26 @@ func DiscordOAuthCallback(c *RequestContext) ResponseData {
 			return c.RejectRequest(fmt.Sprintf("There is already a Handmade Network account with the username \"%s\".", user.Username))
 		}
 
+		var avatarAssetID *uuid.UUID
+		if user.Avatar != nil {
+			// Note! Not using the transaction here. Don't want to fail the login due to avatars.
+			if avatarAsset, err := saveDiscordAvatar(c, c.Conn, user.ID, *user.Avatar); err == nil {
+				avatarAssetID = &avatarAsset.ID
+			} else {
+				c.Logger.Warn().Err(err).Msg("failed to save Discord avatar")
+			}
+		}
+
 		newHMNUser, err := db.QueryOne[models.User](c, tx,
 			`
 			INSERT INTO hmn_user (
-				username, email, password, date_joined, registration_ip
+				username, email, password, avatar_asset_id, date_joined, registration_ip
 			) VALUES (
-				$1,       $2,    '',       $3,          $4
+				$1,       $2,    '',       $3,              $4,          $5
 			)
 			RETURNING $columns
 			`,
-			user.Username, strings.ToLower(user.Email), time.Now(), c.GetIP(),
+			user.Username, strings.ToLower(user.Email), avatarAssetID, time.Now(), c.GetIP(),
 		)
 		if err != nil {
 			return c.ErrorResponse(http.StatusInternalServerError, oops.New(err, "failed to create new HMN user for Discord login"))
@@ -366,3 +379,29 @@ func DiscordShowcaseBacklog(c *RequestContext) ResponseData {
 
 	return c.Redirect(hmnurl.BuildUserProfile(c.CurrentUser.Username), http.StatusSeeOther)
 }
+
+func saveDiscordAvatar(ctx context.Context, conn db.ConnOrTx, userID, avatarHash string) (*models.Asset, error) {
+	const size = 256
+
+	filename := fmt.Sprintf("%s.png", avatarHash)
+	url := fmt.Sprintf("https://cdn.discordapp.com/avatars/%s/%s?size=%d", userID, filename, size)
+
+	content, _, err := discord.DownloadDiscordResource(ctx, url)
+	if err != nil {
+		return nil, oops.New(err, "failed to download Discord avatar")
+	}
+
+	asset, err := assets.Create(ctx, conn, assets.CreateInput{
+		Content:     content,
+		Filename:    filename,
+		ContentType: "image/png",
+
+		Width:  size,
+		Height: size,
+	})
+	if err != nil {
+		return nil, oops.New(err, "failed to save asset for Discord attachment")
+	}
+
+	return asset, nil
+}