oppi.li
source dump of claude code
1import { API_IMAGE_MAX_BASE64_SIZE } from '../constants/apiLimits.js'
2import { logEvent } from '../services/analytics/index.js'
3import { formatFileSize } from './format.js'
4
5/**
6 * Information about an oversized image.
7 */
8export type OversizedImage = {
9 index: number
10 size: number
11}
12
13/**
14 * Error thrown when one or more images exceed the API size limit.
15 */
16export class ImageSizeError extends Error {
17 constructor(oversizedImages: OversizedImage[], maxSize: number) {
18 let message: string
19 const firstImage = oversizedImages[0]
20 if (oversizedImages.length === 1 && firstImage) {
21 message =
22 `Image base64 size (${formatFileSize(firstImage.size)}) exceeds API limit (${formatFileSize(maxSize)}). ` +
23 `Please resize the image before sending.`
24 } else {
25 message =
26 `${oversizedImages.length} images exceed the API limit (${formatFileSize(maxSize)}): ` +
27 oversizedImages
28 .map(img => `Image ${img.index}: ${formatFileSize(img.size)}`)
29 .join(', ') +
30 `. Please resize these images before sending.`
31 }
32 super(message)
33 this.name = 'ImageSizeError'
34 }
35}
36
37/**
38 * Type guard to check if a block is a base64 image block
39 */
40function isBase64ImageBlock(
41 block: unknown,
42): block is { type: 'image'; source: { type: 'base64'; data: string } } {
43 if (typeof block !== 'object' || block === null) return false
44 const b = block as Record<string, unknown>
45 if (b.type !== 'image') return false
46 if (typeof b.source !== 'object' || b.source === null) return false
47 const source = b.source as Record<string, unknown>
48 return source.type === 'base64' && typeof source.data === 'string'
49}
50
51/**
52 * Validates that all images in messages are within the API size limit.
53 * This is a safety net at the API boundary to catch any oversized images
54 * that may have slipped through upstream processing.
55 *
56 * Note: The API's 5MB limit applies to the base64-encoded string length,
57 * not the decoded raw bytes.
58 *
59 * Works with both UserMessage/AssistantMessage types (which have { type, message })
60 * and raw MessageParam types (which have { role, content }).
61 *
62 * @param messages - Array of messages to validate
63 * @throws ImageSizeError if any image exceeds the API limit
64 */
65export function validateImagesForAPI(messages: unknown[]): void {
66 const oversizedImages: OversizedImage[] = []
67 let imageIndex = 0
68
69 for (const msg of messages) {
70 if (typeof msg !== 'object' || msg === null) continue
71
72 const m = msg as Record<string, unknown>
73
74 // Handle wrapped message format { type: 'user', message: { role, content } }
75 // Only check user messages
76 if (m.type !== 'user') continue
77
78 const innerMessage = m.message as Record<string, unknown> | undefined
79 if (!innerMessage) continue
80
81 const content = innerMessage.content
82 if (typeof content === 'string' || !Array.isArray(content)) continue
83
84 for (const block of content) {
85 if (isBase64ImageBlock(block)) {
86 imageIndex++
87 // Check the base64-encoded string length directly (not decoded bytes)
88 // The API limit applies to the base64 payload size
89 const base64Size = block.source.data.length
90 if (base64Size > API_IMAGE_MAX_BASE64_SIZE) {
91 logEvent('tengu_image_api_validation_failed', {
92 base64_size_bytes: base64Size,
93 max_bytes: API_IMAGE_MAX_BASE64_SIZE,
94 })
95 oversizedImages.push({ index: imageIndex, size: base64Size })
96 }
97 }
98 }
99 }
100
101 if (oversizedImages.length > 0) {
102 throw new ImageSizeError(oversizedImages, API_IMAGE_MAX_BASE64_SIZE)
103 }
104}