'use server';

import { GoogleGenerativeAI, SchemaType, HarmCategory, HarmBlockThreshold } from '@google/generative-ai';
import { BottleMetadataSchema, AnalysisResponse } from '@/types/whisky';
import { createClient } from '@/lib/supabase/server';
import { createHash } from 'crypto';
import { trackApiUsage } from '@/services/track-api-usage';
import { checkCreditBalance, deductCredits } from '@/services/credit-service';
import { getAIProvider, getOpenRouterClient, OPENROUTER_PROVIDER_PREFERENCES } from '@/lib/openrouter';
import sharp from 'sharp';

// Native Schema Definition for Gemini API
const metadataSchema = {
    description: "Technical metadata extracted from whisky label",
    type: SchemaType.OBJECT as const,
    properties: {
        name: { type: SchemaType.STRING, description: "Full whisky name including vintage/age", nullable: false },
        distillery: { type: SchemaType.STRING, description: "Distillery name", nullable: true },
        bottler: { type: SchemaType.STRING, description: "Independent bottler if applicable", nullable: true },
        category: { type: SchemaType.STRING, description: "Whisky category (e.g., Single Malt, Blended)", nullable: true },
        abv: { type: SchemaType.NUMBER, description: "Alcohol by volume percentage", nullable: true },
        age: { type: SchemaType.NUMBER, description: "Age statement in years", nullable: true },
        vintage: { type: SchemaType.STRING, description: "Vintage year", nullable: true },
        distilled_at: { type: SchemaType.STRING, description: "Distillation date", nullable: true },
        bottled_at: { type: SchemaType.STRING, description: "Bottling date", nullable: true },
        batch_info: { type: SchemaType.STRING, description: "Batch or cask information", nullable: true },
        bottleCode: { type: SchemaType.STRING, description: "Bottle code or serial number", nullable: true },
        is_whisky: { type: SchemaType.BOOLEAN, description: "Whether this is a whisky product", nullable: false },
        confidence: { type: SchemaType.NUMBER, description: "Confidence score 0-1", nullable: false },
    },
    required: ["name", "is_whisky", "confidence"],
};

const SCAN_PROMPT = `Extract whisky label metadata. Return JSON with:
- name: Full product name
- distillery: Distillery name
- bottler: Independent bottler if applicable
- category: e.g. "Single Malt", "Bourbon"
- abv: Alcohol percentage
- age: Age statement in years
- vintage: Vintage year
- distilled_at: Distillation date
- bottled_at: Bottling date
- batch_info: Batch or cask info
- is_whisky: boolean
- confidence: 0-1`;

export async function scanLabel(input: any): Promise<AnalysisResponse> {
    const provider = getAIProvider();

    // Check API key based on provider
    if (provider === 'gemini' && !process.env.GEMINI_API_KEY) {
        return { success: false, error: 'GEMINI_API_KEY is not configured.' };
    }
    if (provider === 'openrouter' && !process.env.OPENROUTER_API_KEY) {
        return { success: false, error: 'OPENROUTER_API_KEY is not configured.' };
    }

    let supabase;
    try {
        const getValue = (obj: any, key: string): any => {
            if (obj && typeof obj.get === 'function') return obj.get(key);
            if (obj && typeof obj[key] !== 'undefined') return obj[key];
            return null;
        };

        const file = getValue(input, 'file') as File;
        if (!file) {
            return { success: false, error: 'Kein Bild empfangen.' };
        }

        supabase = await createClient();
        const { data: { user } } = await supabase.auth.getUser();

        if (!user) {
            return { success: false, error: 'Nicht autorisiert.' };
        }

        const userId = user.id;
        const creditCheck = await checkCreditBalance(userId, 'gemini_ai');

        if (!creditCheck.allowed) {
            return {
                success: false,
                error: `Nicht genügend Credits. Benötigt: ${creditCheck.cost}, Verfügbar: ${creditCheck.balance}.`
            };
        }

        const perfTotal = performance.now();

        // Step 1: Image Preparation
        const startImagePrep = performance.now();
        const arrayBuffer = await file.arrayBuffer();
        const buffer = Buffer.from(arrayBuffer);
        const imageHash = createHash('sha256').update(buffer).digest('hex');
        const endImagePrep = performance.now();

        // Step 2: Cache Check
        const startCacheCheck = performance.now();
        const { data: cachedResult } = await supabase
            .from('vision_cache')
            .select('result')
            .eq('hash', imageHash)
            .maybeSingle();
        const endCacheCheck = performance.now();

        if (cachedResult) {
            return {
                success: true,
                data: cachedResult.result as any,
                perf: {
                    imagePrep: endImagePrep - startImagePrep,
                    cacheCheck: endCacheCheck - startCacheCheck,
                    apiCall: 0,
                    parsing: 0,
                    validation: 0,
                    dbOps: 0,
                    uploadSize: buffer.length,
                    total: performance.now() - perfTotal,
                    cacheHit: true
                }
            };
        }

        // Step 3: AI-Specific Image Optimization
        const startOptimization = performance.now();
        const optimizedBuffer = await sharp(buffer)
            .resize(1024, 1024, { fit: 'inside', withoutEnlargement: true })
            .grayscale()
            .normalize()
            .toBuffer();
        const endOptimization = performance.now();

        // Step 4: Base64 Encoding
        const startEncoding = performance.now();
        const base64Data = optimizedBuffer.toString('base64');
        const mimeType = 'image/webp';
        const uploadSize = optimizedBuffer.length;
        const endEncoding = performance.now();

        // Step 5: AI Analysis
        const startAiTotal = performance.now();
        let jsonData;
        let validatedData;

        try {
            console.log(`[ScanLabel] Using provider: ${provider}`);

            if (provider === 'openrouter') {
                // OpenRouter path
                const client = getOpenRouterClient();
                const startApi = performance.now();

                const response = await client.chat.completions.create({
                    model: 'google/gemma-3-27b-it',
                    messages: [{
                        role: 'user',
                        content: [
                            { type: 'image_url', image_url: { url: `data:${mimeType};base64,${base64Data}` } },
                            { type: 'text', text: SCAN_PROMPT + '\n\nRespond ONLY with valid JSON.' },
                        ],
                    }],
                    temperature: 0.1,
                    max_tokens: 1024,
                    // @ts-ignore
                    provider: OPENROUTER_PROVIDER_PREFERENCES,
                });

                const endApi = performance.now();
                const content = response.choices[0]?.message?.content || '{}';

                const startParse = performance.now();
                let jsonStr = content;
                const jsonMatch = content.match(/```(?:json)?\s*([\s\S]*?)```/);
                if (jsonMatch) jsonStr = jsonMatch[1].trim();
                jsonData = JSON.parse(jsonStr);
                const endParse = performance.now();

                const startValidation = performance.now();
                validatedData = BottleMetadataSchema.parse(jsonData);
                const endValidation = performance.now();

                await supabase.from('vision_cache').insert({ hash: imageHash, result: validatedData });

                await trackApiUsage({
                    userId: userId,
                    apiType: 'gemini_ai',
                    endpoint: 'scanLabel_openrouter',
                    success: true,
                    provider: 'openrouter',
                    model: 'google/gemma-3-27b-it',
                    responseText: content
                });
                await deductCredits(userId, 'gemini_ai', 'Bottle OCR scan (OpenRouter)');

                return {
                    success: true,
                    data: validatedData,
                    perf: {
                        imagePrep: endImagePrep - startImagePrep,
                        optimization: endOptimization - startOptimization,
                        cacheCheck: endCacheCheck - startCacheCheck,
                        encoding: endEncoding - startEncoding,
                        apiCall: endApi - startApi,
                        parsing: endParse - startParse,
                        validation: endValidation - startValidation,
                        total: performance.now() - perfTotal,
                        cacheHit: false
                    },
                    raw: jsonData
                } as any;

            } else {
                // Gemini path
                const startModelInit = performance.now();
                const genAI = new GoogleGenerativeAI(process.env.GEMINI_API_KEY!);
                const model = genAI.getGenerativeModel({
                    model: 'gemini-2.5-flash',
                    generationConfig: {
                        responseMimeType: "application/json",
                        responseSchema: metadataSchema as any,
                        temperature: 0.1,
                    },
                    safetySettings: [
                        { category: HarmCategory.HARM_CATEGORY_HARASSMENT, threshold: HarmBlockThreshold.BLOCK_NONE },
                        { category: HarmCategory.HARM_CATEGORY_HATE_SPEECH, threshold: HarmBlockThreshold.BLOCK_NONE },
                        { category: HarmCategory.HARM_CATEGORY_SEXUALLY_EXPLICIT, threshold: HarmBlockThreshold.BLOCK_NONE },
                        { category: HarmCategory.HARM_CATEGORY_DANGEROUS_CONTENT, threshold: HarmBlockThreshold.BLOCK_NONE },
                    ] as any,
                });
                const endModelInit = performance.now();

                const startApi = performance.now();
                const result = await model.generateContent([
                    { inlineData: { data: base64Data, mimeType: mimeType } },
                    { text: 'Extract whisky label metadata.' },
                ]);
                const endApi = performance.now();

                const startParse = performance.now();
                jsonData = JSON.parse(result.response.text());
                const endParse = performance.now();

                const startValidation = performance.now();
                validatedData = BottleMetadataSchema.parse(jsonData);
                const endValidation = performance.now();

                await supabase.from('vision_cache').insert({ hash: imageHash, result: validatedData });

                await trackApiUsage({
                    userId: userId,
                    apiType: 'gemini_ai',
                    endpoint: 'scanLabel_gemini',
                    success: true,
                    provider: 'google',
                    model: 'gemini-2.5-flash',
                    responseText: result.response.text()
                });
                await deductCredits(userId, 'gemini_ai', 'Bottle OCR scan (Gemini)');

                return {
                    success: true,
                    data: validatedData,
                    perf: {
                        imagePrep: endImagePrep - startImagePrep,
                        optimization: endOptimization - startOptimization,
                        cacheCheck: endCacheCheck - startCacheCheck,
                        encoding: endEncoding - startEncoding,
                        modelInit: endModelInit - startModelInit,
                        apiCall: endApi - startApi,
                        parsing: endParse - startParse,
                        validation: endValidation - startValidation,
                        total: performance.now() - perfTotal,
                        cacheHit: false
                    },
                    raw: jsonData
                } as any;
            }

        } catch (aiError: any) {
            console.warn(`[ScanLabel] ${provider} failed:`, aiError.message);

            await trackApiUsage({
                userId: userId,
                apiType: 'gemini_ai',
                endpoint: `scanLabel_${provider}`,
                success: false,
                errorMessage: aiError.message,
                provider: provider,
                model: provider === 'openrouter' ? 'google/gemma-3-27b-it' : 'gemini-2.5-flash'
            });

            return {
                success: false,
                isAiError: true,
                error: aiError.message,
                imageHash: imageHash
            } as any;
        }

    } catch (error) {
        console.error('Scan Label Global Error:', error);
        return {
            success: false,
            error: error instanceof Error ? error.message : 'Fehler bei der Label-Analyse.',
        };
    }
}