import express from 'express';
import bodyParser from 'body-parser';
import cors from 'cors';
import { StateManager } from './stateManager.js';
import { AIEngine } from './aiEngine.js';
import fs from 'fs';
import admin from 'firebase-admin';

// --- FIREBASE SETUP ---
// Using environment variable injection as requested
let db = null;
try {
    if (process.env.FIREBASE_SERVICE_ACCOUNT_JSON && process.env.FIREBASE_SERVICE_ACCOUNT_JSON !== "") {
        const serviceAccount = JSON.parse(process.env.FIREBASE_SERVICE_ACCOUNT_JSON);
        admin.initializeApp({
            credential: admin.credential.cert(serviceAccount),
            // Make sure to replace this URL or add it to env variables as well
            databaseURL: "https://shago-web-default-rtdb.firebaseio.com" 
        });
        db = admin.database();
        console.log("🔥 Firebase Connected");
    } else {
        console.warn("⚠️ No FIREBASE_SERVICE_ACCOUNT_JSON found. Running in Memory-Only mode.");
    }
} catch (e) {
    console.error("Firebase Init Error:", e);
}

const app = express();
const PORT = process.env.PORT || 7860;

// Load Prompts for Server-Side Logic Checks
const sysPrompts = JSON.parse(fs.readFileSync('./prompts.json', 'utf8'));

app.use(cors());
app.use(bodyParser.json({ limit: '50mb' }));

// --- HELPERS ---
const validateRequest = (req, res, next) => {
    if (req.path.includes('/onboarding')) return next();
    
    const { userId, projectId } = req.body;
    if (!userId || !projectId) return res.status(400).json({ error: "Missing ID" });
    next();
};

function extractWorkerPrompt(text) {
    const match = text.match(/WORKER_PROMPT:\s*(.*)/s);
    return match ? match[1].trim() : null;
}

function formatContext({ hierarchyContext, scriptContext, logContext }) {
    let out = "";
    if (scriptContext) out += `\n[TARGET SCRIPT]: ${scriptContext.targetName}\n[SOURCE PREVIEW]: ${scriptContext.scriptSource?.substring(0, 1000)}...`;
    if (logContext) out += `\n[LAST LOGS]: ${logContext.logs}`;
    return out;
}

function extractPMQuestion(text) {
    const match = text.match(/\[ASK_PM:\s*(.*?)\]/s); 
    return match ? match[1].trim() : null;
}

function extractImagePrompt(text) {
    const match = text.match(/\[GENERATE_IMAGE:\s*(.*?)\]/s);
    return match ? match[1].trim() : null;
}

// --- ONBOARDING ENDPOINTS ---
/**
 * 1. ANALYZE
 */
app.post('/onboarding/analyze', validateRequest, async (req, res) => {
    const { description } = req.body;
    if (!description) return res.status(400).json({ error: "Description required" });

    try {
        console.log(`[Onboarding] Analyzing idea...`);
        const result = await AIEngine.generateEntryQuestions(description);
        
        if (result.status === "REJECTED") {
            return res.json({ 
                rejected: true, 
                reason: result.reason || "Idea violates TOS or guidelines." 
            });
        }
        res.json({ questions: result.questions });
    } catch (err) {
        console.error(err);
        res.status(500).json({ error: "Analysis failed" });
    }
});

/**
 * 2. CREATE
 */
app.post('/onboarding/create', validateRequest, async (req, res) => {
    const { userId, description, answers } = req.body;
    const projectId = "proj_" + Date.now(); 

    try {
        console.log(`[Onboarding] Grading Project ${projectId}...`);

        // STEP 1: GRADE
        const grading = await AIEngine.gradeProject(description, answers);
        
        // STEP 2: CHECK FAIL CONDITIONS (Relaxed)
        // Only fail if Feasibility is extremely low (< 30) or Rating is F
        const isFailure = grading.feasibility < 30 || grading.rating === 'F';

        let thumbnailBase64 = null;

        if (isFailure) {
            console.log(`[Onboarding] ❌ Project Failed Grading (${grading.rating}). Skipping Image.`);
        } else {
            console.log(`[Onboarding] ✅ Passed. Generating Thumbnail...`);
            
            // --- CRITICAL FIX HERE ---
            // We MUST send the description so the AI knows what to draw.
            const imagePrompt = `Game Title: ${grading.title}. Core Concept: ${description}`;
            thumbnailBase64 = await AIEngine.generateImage(imagePrompt);
        }

        const projectData = {
            id: projectId,
            userId,
            title: grading.title || "Untitled Project",
            description,
            answers,
            stats: grading,
            thumbnail: thumbnailBase64, // ? `data:image/png;base64,${thumbnailBase64}` : null,
            createdAt: Date.now(),
            status: isFailure ? "rejected" : "initialized"
        };

        if (db) await db.ref(`projects/${projectId}`).set(projectData);
        
        if (!isFailure) {
            await StateManager.updateProject(projectId, {
                ...projectData,
                workerHistory: [],
                pmHistory: [],
                failureCount: 0
            });
        }

        res.json({ 
            success: !isFailure, 
            projectId, 
            stats: grading, 
            title: projectData.title,
            thumbnail: projectData.thumbnail 
        });

    } catch (err) {
        console.error("Create Error:", err);
        res.status(500).json({ error: "Creation failed" });
    }
});


// --- CORE WORKFLOW ENDPOINTS ---

/**
 * 3. INITIALIZE WORKSPACE (PM Generates GDD -> First Task)
 */
app.post('/new/project', validateRequest, async (req, res) => {
    const { userId, projectId, description } = req.body;

    try {
        const pmHistory = [];
        const gddPrompt = `Create a comprehensive GDD for: ${description}`;
        const gddResponse = await AIEngine.callPM(pmHistory, gddPrompt);
        
        pmHistory.push({ role: 'user', parts: [{ text: gddPrompt }] });
        pmHistory.push({ role: 'model', parts: [{ text: gddResponse }] });

        const taskPrompt = "Based on the GDD, generate the first technical milestone.\nOutput format:\nTASK_NAME: <Name>\nWORKER_PROMPT: <Specific, isolated instructions for the worker>";
        const taskResponse = await AIEngine.callPM(pmHistory, taskPrompt);

        pmHistory.push({ role: 'user', parts: [{ text: taskPrompt }] });
        pmHistory.push({ role: 'model', parts: [{ text: taskResponse }] });

        const initialWorkerInstruction = extractWorkerPrompt(taskResponse) || `Initialize structure for: ${description}`;

        const workerHistory = [];
        const initialWorkerPrompt = `CONTEXT: New Project. \nINSTRUCTION: ${initialWorkerInstruction}`;
        const workerResponse = await AIEngine.callWorker(workerHistory, initialWorkerPrompt, []);

        workerHistory.push({ role: 'user', parts: [{ text: initialWorkerPrompt }] });
        workerHistory.push({ role: 'model', parts: [{ text: workerResponse }] });

        // Update State
        await StateManager.updateProject(projectId, {
            userId,
            pmHistory,
            workerHistory,
            gdd: gddResponse,
            failureCount: 0
        });

        // Queue Actions
        await processAndQueueResponse(projectId, workerResponse);

        res.json({ success: true, message: "Workspace Initialized", gddPreview: gddResponse.substring(0, 200) });

    } catch (err) {
        console.error("Init Error:", err);
        res.status(500).json({ error: "Initialization Failed" });
    }
});

/**
 * 4. FEEDBACK LOOP (The "Brain")
 */
app.post('/project/feedback', async (req, res) => {
    const { projectId, prompt, hierarchyContext, scriptContext, logContext, taskComplete, images } = req.body;
    
    const project = await StateManager.getProject(projectId);
    if (!project) return res.status(404).json({ error: "Project not found." });

    // A. TASK COMPLETE -> SCOPE SWITCH
    if (taskComplete) {
        console.log(`[${projectId}] ✅ TASK COMPLETE.`);
        
        const summary = `Worker completed the previous task. Logs: ${logContext?.logs || "Clean"}. \nGenerate the NEXT task using 'WORKER_PROMPT:' format.`;
        const pmResponse = await AIEngine.callPM(project.pmHistory, summary);
        
        project.pmHistory.push({ role: 'user', parts: [{ text: summary }] });
        project.pmHistory.push({ role: 'model', parts: [{ text: pmResponse }] });

        const nextInstruction = extractWorkerPrompt(pmResponse);
        if (!nextInstruction) {
             await StateManager.updateProject(projectId, { pmHistory: project.pmHistory, status: "IDLE" });
             return res.json({ success: true, message: "No further tasks. Project Idle." });
        }

        console.log(`[${projectId}] 🧹 Nuking Worker for next task.`);
        const newWorkerHistory = [];
        const newPrompt = `New Objective: ${nextInstruction}`;
        const workerResponse = await AIEngine.callWorker(newWorkerHistory, newPrompt, []);

        newWorkerHistory.push({ role: 'user', parts: [{ text: newPrompt }] });
        newWorkerHistory.push({ role: 'model', parts: [{ text: workerResponse }] });

        await StateManager.updateProject(projectId, {
            pmHistory: project.pmHistory,
            workerHistory: newWorkerHistory,
            failureCount: 0
        });

        StateManager.queueCommand(projectId, { type: "EXECUTE", payload: "warn('Starting Next Task...')" });
        await processAndQueueResponse(projectId, workerResponse);

        return res.json({ success: true, message: "Next Task Assigned" });
    }

    // B. ERROR ESCALATION
    let isFailure = false;
    if (logContext?.logs) {
        const errs = ["Error", "Exception", "failed", "Stack Begin", "Infinite yield"];
        if (errs.some(k => logContext.logs.includes(k))) {
            isFailure = true;
            project.failureCount = (project.failureCount || 0) + 1;
        }
    }

    if (project.failureCount > 3) {
        console.log(`[${projectId}] 🚨 Escalating to PM...`);
        const pmPrompt = sysPrompts.pm_guidance_prompt.replace('{{LOGS}}', logContext?.logs);
        const pmVerdict = await AIEngine.callPM(project.pmHistory, pmPrompt);

        if (pmVerdict.includes("[TERMINATE]")) {
            const fixInstruction = pmVerdict.replace("[TERMINATE]", "").trim();
            const resetHistory = [];
            const resetPrompt = `[SYSTEM]: Previous worker terminated. \nNew Objective: ${fixInstruction}`;
            const workerResp = await AIEngine.callWorker(resetHistory, resetPrompt, []);
            
            resetHistory.push({ role: 'user', parts: [{ text: resetPrompt }] });
            resetHistory.push({ role: 'model', parts: [{ text: workerResp }] });

            await StateManager.updateProject(projectId, { workerHistory: resetHistory, failureCount: 0 });
            StateManager.queueCommand(projectId, { type: "EXECUTE", payload: "print('SYSTEM: Worker Reset')" });
            await processAndQueueResponse(projectId, workerResp);
            
            return res.json({ success: true, message: "Worker Terminated." });
        } else {
            const injection = `[PM GUIDANCE]: ${pmVerdict} \n\nApply this fix now.`;
            const workerResp = await AIEngine.callWorker(project.workerHistory, injection, []);
            
            project.workerHistory.push({ role: 'user', parts: [{ text: injection }] });
            project.workerHistory.push({ role: 'model', parts: [{ text: workerResp }] });
            
            await StateManager.updateProject(projectId, { workerHistory: project.workerHistory, failureCount: 1 });
            await processAndQueueResponse(projectId, workerResp);
            
            return res.json({ success: true, message: "PM Guidance Applied." });
        }
    }

    // C. STANDARD LOOP + CONSULTATION
    try {
        const fullInput = `USER: ${prompt || "Automatic Feedback"}` + formatContext({ hierarchyContext, scriptContext, logContext });
        
        let response = await AIEngine.callWorker(project.workerHistory, fullInput, images || []);
        
        // CHECK: Consultant Question
        const pmQuestion = extractPMQuestion(response);
        if (pmQuestion) {
            console.log(`[${projectId}] 🙋 Worker asking PM: "${pmQuestion}"`);
            
            const pmConsultPrompt = `[WORKER CONSULTATION]: The Worker asks: "${pmQuestion}"\nProvide a technical answer to unblock them.`;
            const pmAnswer = await AIEngine.callPM(project.pmHistory, pmConsultPrompt);

            // Update PM Context
            project.pmHistory.push({ role: 'user', parts: [{ text: pmConsultPrompt }] });
            project.pmHistory.push({ role: 'model', parts: [{ text: pmAnswer }] });

            // Feed Answer Back
            const injectionMsg = `[PM RESPONSE]: ${pmAnswer}`;
            project.workerHistory.push({ role: 'user', parts: [{ text: fullInput }] });
            project.workerHistory.push({ role: 'model', parts: [{ text: response }] });
            
            // Resume Worker
            response = await AIEngine.callWorker(project.workerHistory, injectionMsg, []);
            project.workerHistory.push({ role: 'user', parts: [{ text: injectionMsg }] });
            project.workerHistory.push({ role: 'model', parts: [{ text: response }] });
        } else {
            project.workerHistory.push({ role: 'user', parts: [{ text: fullInput }] });
            project.workerHistory.push({ role: 'model', parts: [{ text: response }] });
        }

        await StateManager.updateProject(projectId, { 
            workerHistory: project.workerHistory,
            pmHistory: project.pmHistory, 
            failureCount: project.failureCount 
        });
        
        await processAndQueueResponse(projectId, response);
        res.json({ success: true });

    } catch (err) {
        console.error("AI Error:", err);
        res.status(500).json({ error: "AI Failed" });
    }
});

/**
 * 5. PING (Plugin Polling)
 */
app.post('/project/ping', async (req, res) => {
    const { projectId } = req.body;
    const command = await StateManager.popCommand(projectId);
    
    if (command) {
        if (command.payload === "CLEAR_CONSOLE") {
             res.json({ action: "CLEAR_LOGS" });
        } else {
            res.json({ 
                action: command.type, 
                target: command.payload, 
                code: command.type === 'EXECUTE' ? command.payload : null 
            });
        }
    } else {
        res.json({ action: "IDLE" });
    }
});

/**
 * 6. MANUAL OVERRIDE
 */
app.post('/human/override', validateRequest, async (req, res) => {
    const { projectId, instruction, pruneHistory } = req.body;
    const project = await StateManager.getProject(projectId);
    
    const overrideMsg = `[SYSTEM OVERRIDE]: ${instruction}`;
    
    if (pruneHistory && project.workerHistory.length >= 2) {
        project.workerHistory.pop();
        project.workerHistory.pop();
    }

    const response = await AIEngine.callWorker(project.workerHistory, overrideMsg, []);
    project.workerHistory.push({ role: 'user', parts: [{ text: overrideMsg }] });
    project.workerHistory.push({ role: 'model', parts: [{ text: response }] });

    await StateManager.updateProject(projectId, { workerHistory: project.workerHistory });
    await processAndQueueResponse(projectId, response);
    res.json({ success: true });
});


// --- RESPONSE PROCESSOR ---
async function processAndQueueResponse(projectId, rawResponse) {
    // 1. Intercept Image Requests
    const imgPrompt = extractImagePrompt(rawResponse);
    if (imgPrompt) {
        console.log(`[${projectId}] 🎨 Generating Asset: ${imgPrompt}`);
        const base64Image = await AIEngine.generateImage(imgPrompt);
        
        if (base64Image) {
            // Queue asset creation for Plugin
            await StateManager.queueCommand(projectId, {
                type: "CREATE_ASSET", 
                payload: base64Image
            });
        }
    }

    // 2. Queue the Raw Response (StateManager parses code)
    await StateManager.queueCommand(projectId, rawResponse);
}

app.listen(PORT, () => {
    console.log(`AI Backend Running on ${PORT}`);
});