'use client';

import { useState, useEffect } from 'react';
import { getTodayISOString } from './dateUtils';

export interface GameState {
    date: string;
    guesses: string[]; // Array of song titles or IDs guessed
    isSolved: boolean;
    isFailed: boolean;
    lastPlayed: number; // Timestamp
}

export interface Statistics {
    solvedIn1: number;
    solvedIn2: number;
    solvedIn3: number;
    solvedIn4: number;
    solvedIn5: number;
    solvedIn6: number;
    solvedIn7: number;
    failed: number;
}

const STORAGE_KEY = 'hoerdle_game_state';
const STATS_KEY = 'hoerdle_statistics';

export function useGameState() {
    const [gameState, setGameState] = useState<GameState | null>(null);
    const [statistics, setStatistics] = useState<Statistics | null>(null);

    useEffect(() => {
        // Load game state
        const stored = localStorage.getItem(STORAGE_KEY);
        const today = getTodayISOString();

        if (stored) {
            const parsed: GameState = JSON.parse(stored);
            if (parsed.date === today) {
                setGameState(parsed);
            } else {
                // New day
                const newState: GameState = {
                    date: today,
                    guesses: [],
                    isSolved: false,
                    isFailed: false,
                    lastPlayed: Date.now(),
                };
                setGameState(newState);
                localStorage.setItem(STORAGE_KEY, JSON.stringify(newState));
            }
        } else {
            // No state
            const newState: GameState = {
                date: today,
                guesses: [],
                isSolved: false,
                isFailed: false,
                lastPlayed: Date.now(),
            };
            setGameState(newState);
            localStorage.setItem(STORAGE_KEY, JSON.stringify(newState));
        }

        // Load statistics
        const storedStats = localStorage.getItem(STATS_KEY);
        if (storedStats) {
            const parsedStats = JSON.parse(storedStats);
            // Migration for existing stats without solvedIn7
            if (parsedStats.solvedIn7 === undefined) {
                parsedStats.solvedIn7 = 0;
            }
            setStatistics(parsedStats);
        } else {
            const newStats: Statistics = {
                solvedIn1: 0,
                solvedIn2: 0,
                solvedIn3: 0,
                solvedIn4: 0,
                solvedIn5: 0,
                solvedIn6: 0,
                solvedIn7: 0,
                failed: 0,
            };
            setStatistics(newStats);
            localStorage.setItem(STATS_KEY, JSON.stringify(newStats));
        }
    }, []);

    const saveState = (newState: GameState) => {
        setGameState(newState);
        localStorage.setItem(STORAGE_KEY, JSON.stringify(newState));
    };

    const updateStatistics = (attempts: number, solved: boolean) => {
        if (!statistics) return;

        const newStats = { ...statistics };

        if (solved) {
            switch (attempts) {
                case 1: newStats.solvedIn1++; break;
                case 2: newStats.solvedIn2++; break;
                case 3: newStats.solvedIn3++; break;
                case 4: newStats.solvedIn4++; break;
                case 5: newStats.solvedIn5++; break;
                case 6: newStats.solvedIn6++; break;
                case 7: newStats.solvedIn7++; break;
            }
        } else {
            newStats.failed++;
        }

        setStatistics(newStats);
        localStorage.setItem(STATS_KEY, JSON.stringify(newStats));
    };

    const addGuess = (guess: string, correct: boolean) => {
        if (!gameState) return;

        const newGuesses = [...gameState.guesses, guess];
        const isSolved = correct;
        const isFailed = !correct && newGuesses.length >= 7;

        const newState = {
            ...gameState,
            guesses: newGuesses,
            isSolved,
            isFailed,
            lastPlayed: Date.now(),
        };

        saveState(newState);

        // Update statistics when game ends
        if (isSolved || isFailed) {
            updateStatistics(newGuesses.length, isSolved);
        }
    };

    return { gameState, statistics, addGuess };
}