const queueManager = require('./queueManager');
const triageEngine = require('./triageEngine');
const i18n = require('./i18n');

/**
 * BotLogic: Simulates the WhatsApp conversational flow
 */
class BotLogic {
    constructor() {
        this.states = {}; // Track session state per patient
    }

    async handleMessage(patientId, message) {
        const text = message.toLowerCase();
        let state = this.states[patientId] || 'IDLE';
        let lang = this.states[`${patientId}_lang`] || 'en';

        // 1. Language Selection (First time or reset)
        if (text.includes('hi') && !this.states[`${patientId}_lang`]) {
            this.states[patientId] = 'SELECT_LANG';
            return {
                reply: "Welcome to Curio! Please select your language / भाषा चुनें / భాషను ఎంచుకోండి:\n\n1. English\n2. Hindi (हिंदी)\n3. Telugu (తెలుగు)",
                buttons: ["English", "Hindi", "Telugu"]
            };
        }

        if (state === 'SELECT_LANG') {
            if (text.includes('hindi')) lang = 'hi';
            if (text.includes('telugu')) lang = 'te';
            this.states[`${patientId}_lang`] = lang;
            this.states[patientId] = 'IDLE';
            state = 'IDLE'; // Continue to welcome
        }

        // 2. Initial Greeting / Booking Intent
        if (state === 'IDLE') {
            return {
                reply: i18n.t(lang, 'welcome'),
                buttons: i18n.getButtons(lang)
            };
        }

        // 2. Booking Flow
        if (text.includes('book for today')) {
            return {
                reply: "Great! Please select your preferred time slot:",
                buttons: ["10:00 AM", "10:30 AM", "11:00 AM"]
            };
        }

        if (text === '10:00 am' || text === '10:30 am') {
            const date = new Date().toISOString().split('T')[0];
            const result = queueManager.bookOnline(date, text.replace(' am', ''));
            
            if (result.success) {
                this.states[patientId] = 'TRIAGE_START';
                return {
                    reply: i18n.t(lang, 'triage_ask', { token: result.token }) + 
                           ` \n\n💳 *Payment Required*: Please pay ₹${result.fee} to activate your token: http://razorpay.me/Curio_mock`,
                };
            } else {
                return {
                    reply: "❌ Sorry, the 10:00 AM online slots are full (Max 3/slot). Would you like to try 11:30 AM?",
                    buttons: ["Try 11:30 AM", "Waitlist Me"]
                };
            }
        }

        // 3. Triage State Handling
        if (this.states[patientId] === 'TRIAGE_START') {
            const analysis = await triageEngine.analyzeSymptoms(text);
            this.states[patientId] = 'TRIAGE_FOLLOWUP';
            this.states[`${patientId}_summary`] = analysis.summary;
            
            return {
                reply: `Thank you. AI Analysis: _${analysis.category}_.\n\nQuick follow-up: ${analysis.followUp}`
            };
        }

        if (this.states[patientId] === 'TRIAGE_FOLLOWUP') {
            this.states[patientId] = 'IDLE';
            return {
                reply: i18n.t(lang, 'triage_done')
            };
        }

        // 4. Daily Updates / Status
        if (text.includes('status') || text.includes('queue') || text.includes('कतार') || text.includes('స్థితి')) {
            return {
                reply: i18n.t(lang, 'status_update', { current: 'WK-3', pos: 'ON-1', wait: '8' })
            };
        }

        if (text.includes('tips') || text.includes('update')) {
            const updates = queueManager.getDailyUpdates(patientId);
            return {
                reply: "🔔 *Daily Updates for You:*\n\n" + updates.join('\n\n')
            };
        }

        // 4. Default Fallback
        return {
            reply: "I'm sorry, I didn't quite catch that. You can type 'Hi' to see the main menu."
        };
    }
}

module.exports = new BotLogic();