Complete Processing Flow

graph TD
    A[API Response] --> B{candidatesTokenCount?}
    B -->|= 0| C[Content Review Rejected]
    B -->|> 0| D{Check candidates}
    D -->|null/empty| E[System Error]
    D -->|exists| F{finishReason?}
    F -->|!= STOP| G[Generation Rejected]
    F -->|= STOP| H{Check parts}
    H -->|empty| I[No Data Error]
    H -->|exists| J{Has image?}
    J -->|Yes| K[Success]
    J -->|No| L{Has text?}
    L -->|Yes| M[Text Response Error]
    L -->|No| N[Unknown Error]

if (data.usageMetadata?.candidatesTokenCount === 0) {
    return {
        errorType: 'ZERO_CANDIDATES_TOKEN',
        userMessage: 'Content review failed'
    };
}

if (!data.candidates || !data.candidates.length) {
    return {
        errorType: 'NO_CANDIDATES',
        userMessage: 'System error, please retry'
    };
}

const candidate = data.candidates[0];
if (candidate.finishReason && candidate.finishReason !== 'STOP') {
    return {
        errorType: 'FINISH_REASON',
        finishReason: candidate.finishReason
    };
}

const parts = candidate.content.parts;
const images = parts.filter(p => p.inlineData?.data);
const texts = parts.filter(p => p.text);

if (images.length > 0) {
    return { success: true, images };
}

if (texts.length > 0) {
    return { errorType: 'TEXT_RESPONSE', text: texts[0].text };
}

return { errorType: 'UNKNOWN' };