import { createSlice, createAsyncThunk } from '@reduxjs/toolkit';
import axios from '../../axios';

// 🔹 Декодирование JWT
function decodeJwt(token: string) {
    const [, payload] = token.split('.');
    const json = atob(payload.replace(/-/g, '+').replace(/_/g, '/'));
    return JSON.parse(decodeURIComponent(escape(json)));
}

// 🔹 Типы
interface AuthState {
    jwt: string | null;
    refreshToken: string | null;
    username: string | null;
    email: string | null;
    id: string | null;
    status: 'idle' | 'loading' | 'successful' | 'failed';
    error: string | null;
}

// 🔹 Инициализация состояния с синхронной загрузкой из localStorage
const jwtFromStorage = localStorage.getItem('jwt');
const refreshTokenFromStorage = localStorage.getItem('refreshToken');

const initialState: AuthState = {
    jwt: jwtFromStorage || null,
    refreshToken: refreshTokenFromStorage || null,
    username: null,
    email: null,
    id: null,
    status: 'idle',
    error: null,
};

// Если токен есть, подставляем в axios и декодируем
if (jwtFromStorage) {
    axios.defaults.headers.common['Authorization'] = `Bearer ${jwtFromStorage}`;
    try {
        const decoded = decodeJwt(jwtFromStorage);
        initialState.username =
            decoded[
                'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name'
            ] || null;
        initialState.email =
            decoded[
                'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress'
            ] || null;
        initialState.id =
            decoded[
                'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier'
            ] || null;
    } catch {
        localStorage.removeItem('jwt');
        localStorage.removeItem('refreshToken');
        delete axios.defaults.headers.common['Authorization'];
    }
}

// 🔹 AsyncThunk-ы (login/register/refresh/whoami) остаются как были
export const registerUser = createAsyncThunk(
    'auth/register',
    async (
        {
            username,
            email,
            password,
        }: { username: string; email: string; password: string },
        { rejectWithValue },
    ) => {
        try {
            const response = await axios.post('/authentication/register', {
                username,
                email,
                password,
            });
            return response.data;
        } catch (err: any) {
            return rejectWithValue(
                err.response?.data?.message || 'Registration failed',
            );
        }
    },
);

export const loginUser = createAsyncThunk(
    'auth/login',
    async (
        { username, password }: { username: string; password: string },
        { rejectWithValue },
    ) => {
        try {
            const response = await axios.post('/authentication/login', {
                username,
                password,
            });
            return response.data;
        } catch (err: any) {
            return rejectWithValue(
                err.response?.data?.message || 'Login failed',
            );
        }
    },
);

export const refreshToken = createAsyncThunk(
    'auth/refresh',
    async ({ refreshToken }: { refreshToken: string }, { rejectWithValue }) => {
        try {
            const response = await axios.post('/authentication/refresh', {
                refreshToken,
            });
            return response.data;
        } catch (err: any) {
            return rejectWithValue(
                err.response?.data?.message || 'Refresh token failed',
            );
        }
    },
);

export const fetchWhoAmI = createAsyncThunk(
    'auth/whoami',
    async (_, { rejectWithValue }) => {
        try {
            const response = await axios.get('/authentication/whoami');
            return response.data;
        } catch (err: any) {
            return rejectWithValue(
                err.response?.data?.message || 'Failed to fetch user info',
            );
        }
    },
);

// 🔹 Slice
const authSlice = createSlice({
    name: 'auth',
    initialState,
    reducers: {
        logout: (state) => {
            state.jwt = null;
            state.refreshToken = null;
            state.username = null;
            state.email = null;
            state.id = null;
            state.status = 'idle';
            state.error = null;
            localStorage.removeItem('jwt');
            localStorage.removeItem('refreshToken');
            delete axios.defaults.headers.common['Authorization'];
        },
    },
    extraReducers: (builder) => {
        // ----------------- Register -----------------
        builder.addCase(registerUser.pending, (state) => {
            state.status = 'loading';
            state.error = null;
        });
        builder.addCase(registerUser.fulfilled, (state, action) => {
            state.status = 'successful';
            state.jwt = action.payload.jwt;
            state.refreshToken = action.payload.refreshToken;

            const decoded = decodeJwt(action.payload.jwt);
            state.username =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name'
                ] || null;
            state.email =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress'
                ] || null;
            state.id =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier'
                ] || null;

            axios.defaults.headers.common[
                'Authorization'
            ] = `Bearer ${action.payload.jwt}`;
            localStorage.setItem('jwt', action.payload.jwt);
            localStorage.setItem('refreshToken', action.payload.refreshToken);
        });
        builder.addCase(registerUser.rejected, (state, action) => {
            state.status = 'failed';
            state.error = action.payload as string;
        });

        // ----------------- Login -----------------
        builder.addCase(loginUser.pending, (state) => {
            state.status = 'loading';
            state.error = null;
        });
        builder.addCase(loginUser.fulfilled, (state, action) => {
            state.status = 'successful';
            state.jwt = action.payload.jwt;
            state.refreshToken = action.payload.refreshToken;

            const decoded = decodeJwt(action.payload.jwt);
            state.username =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name'
                ] || null;
            state.email =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress'
                ] || null;
            state.id =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier'
                ] || null;

            axios.defaults.headers.common[
                'Authorization'
            ] = `Bearer ${action.payload.jwt}`;
            localStorage.setItem('jwt', action.payload.jwt);
            localStorage.setItem('refreshToken', action.payload.refreshToken);
        });
        builder.addCase(loginUser.rejected, (state, action) => {
            state.status = 'failed';
            state.error = action.payload as string;
        });

        // ----------------- Refresh -----------------
        builder.addCase(refreshToken.pending, (state) => {
            state.status = 'loading';
            state.error = null;
        });
        builder.addCase(refreshToken.fulfilled, (state, action) => {
            state.status = 'successful';
            state.jwt = action.payload.jwt;
            state.refreshToken = action.payload.refreshToken;

            const decoded = decodeJwt(action.payload.jwt);
            state.username =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/name'
                ] || null;
            state.email =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/emailaddress'
                ] || null;
            state.id =
                decoded[
                    'http://schemas.xmlsoap.org/ws/2005/05/identity/claims/nameidentifier'
                ] || null;

            axios.defaults.headers.common[
                'Authorization'
            ] = `Bearer ${action.payload.jwt}`;
            localStorage.setItem('jwt', action.payload.jwt);
            localStorage.setItem('refreshToken', action.payload.refreshToken);
        });
        builder.addCase(refreshToken.rejected, (state, action) => {
            state.status = 'failed';
            state.error = action.payload as string;
        });

        // ----------------- WhoAmI -----------------
        builder.addCase(fetchWhoAmI.pending, (state) => {
            state.status = 'loading';
            state.error = null;
        });
        builder.addCase(fetchWhoAmI.fulfilled, (state, action) => {
            state.status = 'successful';
            state.username = action.payload.username;
        });
        builder.addCase(fetchWhoAmI.rejected, (state, action) => {
            state.status = 'failed';
            state.error = action.payload as string;
        });
    },
});

export const { logout } = authSlice.actions;
export const authReducer = authSlice.reducer;