Add more midjourney error handlers

Handle missing message error on upscale and variations.
Handle pending mod message error and abort when it happens.
Improve error when prompt is banned.

pkg/ai/ai.go

@@ -43,6 +43,7 @@ type Image struct {
 type Error struct {
 	error
 	temporary bool
+	fatal     bool
 }
 
 func NewError(err error, temporary bool) Error {
@@ -52,6 +53,13 @@ func NewError(err error, temporary bool) Error {
 	}
 }
 
+func NewFatal(err error) Error {
+	return Error{
+		error: err,
+		fatal: true,
+	}
+}
+
 func (e Error) Error() string {
 	return e.error.Error()
 }
@@ -64,6 +72,10 @@ func (e Error) Temporary() bool {
 	return e.temporary
 }
 
+func (e Error) Fatal() bool {
+	return e.fatal
+}
+
 type entry struct {
 	prompt string
 	index  int
@@ -294,8 +306,13 @@ func retry(ctx context.Context, fn func(context.Context) error) error {
 		if err == nil {
 			return nil
 		}
-		// If the error is not temporary, return it
 		var aiErr Error
+		// If the error is fatal, stop everything
+		if errors.As(err, &aiErr) && aiErr.Fatal() {
+			// TODO: handle fatal errors
+			panic(err)
+		}
+		// If the error is not temporary, return it
 		if errors.As(err, &aiErr) && !aiErr.Temporary() {
 			return err
 		}

pkg/ai/midjourney/midjourney.go

@@ -230,11 +230,16 @@ func parseEmbedFooter(prompt string, msg *discord.Message) (string, error) {
 	return fmt.Sprintf("%s%s", prompt, suffixes), nil
 }
 
+// Errors parsed from messages
 var ErrInvalidParameter = errors.New("invalid parameter")
 var ErrInvalidLink = errors.New("invalid link")
 var ErrBannedPrompt = errors.New("banned prompt")
 var ErrJobQueued = errors.New("job queued")
 var ErrQueueFull = errors.New("queue full")
+var ErrPendingMod = errors.New("pending mod message")
+
+// Other errors
+var ErrMessageNotFound = ai.NewError(errors.New("message not found"), false)
 
 func parseError(msg *discord.Message) error {
 	if len(msg.Embeds) == 0 {
@@ -251,7 +256,7 @@ func parseError(msg *discord.Message) error {
 	case "invalid link":
 		err := fmt.Errorf("midjourney: %w: %s", ErrInvalidLink, desc)
 		return ai.NewError(err, false)
-	case "banned prompt":
+	case "banned prompt", "banned prompt detected":
 		err := fmt.Errorf("midjourney: %w: %s", ErrBannedPrompt, desc)
 		return ai.NewError(err, false)
 	case "job queued":
@@ -260,6 +265,9 @@ func parseError(msg *discord.Message) error {
 	case "queue full":
 		err := fmt.Errorf("midjourney: %w: %s", ErrQueueFull, desc)
 		return ai.NewError(err, true)
+	case "pending mod message":
+		err := fmt.Errorf("midjourney: %w: %s", ErrPendingMod, desc)
+		return ai.NewFatal(err)
 	default:
 		err := fmt.Errorf("midjourney: %s: %s", title, desc)
 		return ai.NewError(err, true)
@@ -517,6 +525,10 @@ func (c *Client) Upscale(ctx context.Context, preview *ai.Preview, index int) (s
 		// response may be received before it finishes, due to rate limit
 		// locking.
 		if _, err := c.c.Do(ctx, "POST", "interactions", upscale); err != nil {
+			// Check if the message was deleted
+			if errors.Is(err, discord.ErrMessageNotFound) {
+				return ErrMessageNotFound
+			}
 			return fmt.Errorf("midjourney: couldn't send upscale interaction: %w", err)
 		}
 		return nil
@@ -553,6 +565,10 @@ func (c *Client) Variation(ctx context.Context, preview *ai.Preview, index int)
 		// response may be received before it finishes, due to rate limit
 		// locking.
 		if _, err := c.c.Do(ctx, "POST", "interactions", variation); err != nil {
+			// Check if the message was deleted
+			if errors.Is(err, discord.ErrMessageNotFound) {
+				return ErrMessageNotFound
+			}
 			return fmt.Errorf("midjourney: couldn't send variation interaction: %w", err)
 		}
 		return nil

pkg/discord/discord.go

@@ -194,6 +194,36 @@ func (c *Client) Do(ctx context.Context, method string, path string, body interf
 
 var errBadGateway = errors.New("discord: bad gateway")
 
+type Error struct {
+	Code      int    `json:"code"`
+	Message   string `json:"message"`
+	temporary bool
+}
+
+func (e Error) Error() string {
+	return fmt.Sprintf("discord: %s (%d)", e.Message, e.Code)
+}
+
+func (e Error) Temporary() bool {
+	return e.temporary
+}
+
+var ErrMessageNotFound = &Error{Message: "Unknown Message", Code: 10008, temporary: false}
+
+func parseError(raw string) error {
+	var err Error
+	if err := json.Unmarshal([]byte(raw), &err); err != nil {
+		return nil
+	}
+	err.temporary = true
+	switch err.Code {
+	case 10008:
+		return ErrMessageNotFound
+	default:
+		return err
+	}
+}
+
 func (c *Client) do(method string, path string, body interface{}) ([]byte, error) {
 	// Rate limit
 	c.doLck.Lock()
@@ -268,6 +298,9 @@ func (c *Client) do(method string, path string, body interface{}) ([]byte, error
 		return nil, errBadGateway
 	}
 	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		if err := parseError(string(data)); err != nil {
+			return nil, err
+		}
 		return nil, fmt.Errorf("discord: request %s returned status code %d (%s)", path, resp.StatusCode, string(data))
 	}
 	return data, nil
@@ -357,6 +390,11 @@ func retry(ctx context.Context, maxAttempts int, fn func() error) error {
 		if attempts >= maxAttempts {
 			return err
 		}
+		// If the error is not temporary, we stop
+		var discordErr Error
+		if errors.As(err, &discordErr) && !discordErr.Temporary() {
+			return err
+		}
 		// Bad gateway usually means discord is down, so we wait before retrying
 		if errors.Is(err, errBadGateway) {
 			idx := attempts - 1