import React, { createContext, useContext, useEffect, useState } from 'react';
import type { User, Session } from '@supabase/supabase-js';
import { supabase } from '../lib/supabaseClient';
import { tableNameUsers, tableNameProfiles } from '../lib/const';

// Define the shape of our extended user profile
export interface UserProfile {
    user_id: string;
    first_name: string;
    last_name: string;
    email: string;
    role: string;

    // Alpaca Settings
    ALPACA_API_KEY?: string;
    ALPACA_SECRET_KEY?: string;
    REAL_ALPACA_API_KEY?: string;
    REAL_ALPACA_SECRET_KEY?: string;

    // Bot Settings
    trade_enable: boolean;
    drop_threshold_for_buy?: string | number;
    gain_threshold_for_sell?: string | number;
    market_poll_interval_in_seconds?: string | number;
}

interface AuthContextType {
    session: Session | null;
    user: User | null;
    profile: UserProfile | null;
    loading: boolean;
    signOut: () => Promise<void>;
    refreshProfile: () => Promise<void>;
}

const AuthContext = createContext<AuthContextType | undefined>(undefined);

const buildFallbackProfile = (authUser: User | null): UserProfile | null => {
    if (!authUser?.id) return null;
    const displayName = String((authUser as any)?.display_name || (authUser as any)?.user_metadata?.displayName || '').trim();
    const parts = displayName ? displayName.split(/\s+/) : [];
    return {
        user_id: authUser.id,
        first_name: parts[0] || '',
        last_name: parts.slice(1).join(' '),
        email: authUser.email || '',
        role: String((authUser as any)?.role || (authUser as any)?.user_metadata?.role || 'member'),
        trade_enable: true,
    };
};

export const shouldCreateDefaultProfile = (profiles: Array<{ id?: string }> | null | undefined) =>
    !profiles || profiles.length === 0;

export const buildDefaultProfilePayload = (userId: string) => ({
    user_id: userId,
    name: 'My First Strategy',
    allocated_capital: 1000,
    risk_per_trade_percent: 1,
    symbols: 'BTC/USDT, ETH/USDT',
    is_active: false,
    strategy_config: {
        rules: [
            { ruleId: 'TrendBiasRule', enabled: true, params: { fastPeriod: 50, slowPeriod: 200 } },
            { ruleId: 'MomentumRule', enabled: true, params: { rsiPeriod: 14, overbought: 70, oversold: 30 } },
            { ruleId: 'ZoneRule', enabled: true, params: { zonePercent: 1.5 } },
            { ruleId: 'SessionRule', enabled: true, params: { sessions: 'London,NY' } },
            { ruleId: 'EntryTriggerRule', enabled: true, params: { showPatterns: true } },
            { ruleId: 'RiskManagementRule', enabled: true, params: { maxRisk: 2.0 } },
            { ruleId: 'AIAnalysisRule', enabled: false, params: { minConfidence: 0.7 } },
        ],
        riskLimits: { maxDailyLossUsd: 50, maxOpenTrades: 3, maxConsecutiveLosses: 2 },
        execution: { orderType: 'market', cooldownMinutes: 30, entryMode: 'both' },
    },
});

export function AuthProvider({ children }: { children: React.ReactNode }) {
    const [session, setSession] = useState<Session | null>(null);
    const [user, setUser] = useState<User | null>(null);
    const [profile, setProfile] = useState<UserProfile | null>(null);
    const [loading, setLoading] = useState(true);

    useEffect(() => {
        // 1. Get initial session
        supabase.auth.getSession().then(({ data: { session } }) => {
            setSession((session as Session | null) ?? null);
            setUser((session?.user as User | null) ?? null);
            if (session?.user) {
                fetchProfile(session.user.id);
            } else {
                setLoading(false);
            }
        });

        // 2. Listen for changes
        const { data: { subscription } } = supabase.auth.onAuthStateChange((_event, session) => {
            setSession((session as Session | null) ?? null);
            setUser((session?.user as User | null) ?? null);
            if (session?.user) {
                fetchProfile(session.user.id);
            } else {
                setProfile(null);
                setLoading(false);
            }
        });

        return () => subscription.unsubscribe();
    }, []);

    const fetchProfile = async (userId: string) => {
        try {
            const { data, error } = await supabase
                .from(tableNameUsers)
                .select('user_id,first_name,last_name,email,role,ALPACA_API_KEY,ALPACA_SECRET_KEY,REAL_ALPACA_API_KEY,REAL_ALPACA_SECRET_KEY,trade_enable,drop_threshold_for_buy,gain_threshold_for_sell,market_poll_interval_in_seconds')
                .eq('user_id', userId)
                .single();

            if (error) {
                console.error('Error fetching user profile:', error);
                setProfile(buildFallbackProfile(user));
                ensureDefaultProfile(userId);
            } else {
                setProfile(data as UserProfile);
                // Ensure a default trading profile exists for new users
                ensureDefaultProfile(userId);
            }
        } catch (err) {
            console.error('Unexpected error fetching profile:', err);
            setProfile(buildFallbackProfile(user));
        } finally {
            setLoading(false);
        }
    };

    const ensureDefaultProfile = async (userId: string) => {
        try {
            const { data } = await supabase
                .from(tableNameProfiles)
                .select('id')
                .eq('user_id', userId)
                .limit(1);

            if (shouldCreateDefaultProfile(data)) {
                console.log('[Auth] No profiles found - creating default profile for new user');
                await supabase.from(tableNameProfiles).insert([buildDefaultProfilePayload(userId)]);
                window.dispatchEvent(new Event('profiles-updated'));
            }
        } catch (err) {
            console.error('[Auth] Error ensuring default profile:', err);
        }
    };

    const signOut = async () => {
        await supabase.auth.signOut();
        setSession(null);
        setUser(null);
        setProfile(null);
    };

    const refreshProfile = async () => {
        if (user) {
            await fetchProfile(user.id);
        }
    }

    const value = {
        session,
        user,
        profile,
        loading,
        signOut,
        refreshProfile
    };

    return <AuthContext.Provider value={value}>{children}</AuthContext.Provider>;
}

export const useAuth = () => {
    const context = useContext(AuthContext);
    if (context === undefined) {
        throw new Error('useAuth must be used within an AuthProvider');
    }
    return context;
};