1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
|
package image
import (
"context"
"fmt"
"strings"
"google.golang.org/genai"
"codeberg.org/snonux/comicforge/internal/apicircuit"
)
func (c *GeminiProvider) generateText(ctx context.Context, model, systemPrompt, userPrompt string, temperature float32, maxOutputTokens int32) (string, error) {
temp := temperature
resp, err := apicircuit.Execute(nil, c.Name(), apicircuit.CapabilityText, func() (*genai.GenerateContentResponse, error) {
return c.client.Models.GenerateContent(ctx, model, []*genai.Content{
genai.NewContentFromText(userPrompt, genai.RoleUser),
}, &genai.GenerateContentConfig{
SystemInstruction: genai.NewContentFromText(systemPrompt, genai.RoleUser),
Temperature: &temp,
MaxOutputTokens: maxOutputTokens,
})
})
if err != nil {
return "", fmt.Errorf("gemini API error: %w", err)
}
text := strings.TrimSpace(resp.Text())
if text == "" {
return "", fmt.Errorf("no response received")
}
return text, nil
}
func geminiImageConfig(aspectRatio string) *genai.GenerateContentConfig {
if aspectRatio == "" {
aspectRatio = geminiAspectRatio
}
return &genai.GenerateContentConfig{
ResponseModalities: []string{string(genai.ModalityImage)},
ImageConfig: &genai.ImageConfig{
AspectRatio: aspectRatio,
},
}
}
func geminiReferenceParts(prompt string, refs [][]byte) []*genai.Part {
parts := make([]*genai.Part, 0, len(refs)+1)
for _, ref := range refs {
if len(ref) == 0 {
continue
}
parts = append(parts, &genai.Part{
InlineData: &genai.Blob{MIMEType: "image/png", Data: ref},
})
}
refNote := fmt.Sprintf(
"The %d reference image(s) above show the exact character appearance that must be preserved. "+
"Every character, animal, or object must keep the same identity, face, costume, colours, and markings. "+
"Use the references for identity only: do not copy their scene, pose, camera angle, panel layout, lighting, action, or background. "+
"The new image must follow the new prompt's story beat and composition. Now generate:\n\n",
len(refs),
)
parts = append(parts, &genai.Part{Text: refNote + prompt})
return parts
}
func (c *GeminiProvider) generateImage(ctx context.Context, prompt, aspectRatio string) ([]byte, string, error) {
cfg := geminiImageConfig(aspectRatio)
resp, err := apicircuit.Execute(nil, c.Name(), apicircuit.CapabilityImage, func() (*genai.GenerateContentResponse, error) {
return c.client.Models.GenerateContent(ctx, c.modelName(), []*genai.Content{
genai.NewContentFromText(prompt, genai.RoleUser),
}, cfg)
})
if err != nil {
return nil, "", &SearchError{
Provider: geminiSource,
Code: "API_ERROR",
Message: fmt.Sprintf("failed to generate image: %v", err),
}
}
imageBytes, mimeType, err := extractGeneratedImage(resp)
if err != nil {
return nil, "", &SearchError{
Provider: geminiSource,
Code: "NO_RESULTS",
Message: err.Error(),
}
}
return imageBytes, mimeType, nil
}
func (c *GeminiProvider) generateImageWithRefs(ctx context.Context, prompt, aspectRatio string, refs [][]byte) ([]byte, string, error) {
cfg := geminiImageConfig(aspectRatio)
parts := geminiReferenceParts(prompt, refs)
resp, err := apicircuit.Execute(nil, c.Name(), apicircuit.CapabilityImage, func() (*genai.GenerateContentResponse, error) {
return c.client.Models.GenerateContent(ctx, c.modelName(), []*genai.Content{
{
Role: string(genai.RoleUser),
Parts: parts,
},
}, cfg)
})
if err != nil {
return nil, "", &SearchError{
Provider: geminiSource,
Code: "API_ERROR",
Message: fmt.Sprintf("failed to generate image with refs: %v", err),
}
}
imageBytes, mimeType, err := extractGeneratedImage(resp)
if err != nil {
return nil, "", &SearchError{
Provider: geminiSource,
Code: "NO_RESULTS",
Message: err.Error(),
}
}
return imageBytes, mimeType, nil
}
func extractGeneratedImage(response *genai.GenerateContentResponse) ([]byte, string, error) {
if response == nil {
return nil, "", fmt.Errorf("no response from Gemini")
}
for _, candidate := range response.Candidates {
if candidate == nil || candidate.Content == nil {
continue
}
for _, part := range candidate.Content.Parts {
if part == nil || part.InlineData == nil || len(part.InlineData.Data) == 0 {
continue
}
mimeType := part.InlineData.MIMEType
if mimeType == "" {
mimeType = "image/png"
}
return append([]byte(nil), part.InlineData.Data...), mimeType, nil
}
}
return nil, "", fmt.Errorf("no image data returned from Gemini")
}
|
