import axios from 'axios';
import { prisma } from "~/db.server";
import { createUserSession } from '~/session.server';

export interface DiscordUser {
    id: string;
    username: string;
    discriminator: string;
    avatar: string;
    bot?: boolean;
    system?: boolean;
    mfa_enabled?: boolean;
}

export interface AccessTokenResponse {
    access_token: string;
    expires: number;
    refresh_token: string;
}

export function getAccessToken(code: string): Promise<AccessTokenResponse> {
    return new Promise(
        (resolve, reject) => {
            const body = new FormData();
            body.append("grant_type", "authorization_code");
            body.append("code", code);
            body.append("redirect_url", process.env.DISCORD_REDIRECT_URI || "");

            axios.post("https://discord.com/api/oauth2/token", body)
                .then((res) => {
                    const { access_token, refresh_token, expires_in } = res.data;

                    resolve({
                        access_token,
                        refresh_token,
                        expires: Date.now() + expires_in * 1000
                    });
                })
                .catch(reject);
        }
    )
}

export async function authorize(access_code: string): Promise<AccessTokenResponse | undefined> {
    return new Promise(
        (resolve, reject) => {
            const formData = new FormData();

            formData.append("client_id", process.env.DISCORD_CLIENT_ID || "");
            formData.append("client_secret", process.env.DISCORD_CLIENT_SECRET || "");
            formData.append("grant_type", "authorization_code");
            formData.append("redirect_uri", process.env.DISCORD_REDIRECT_URI || "");
            formData.append("scope", "identify");
            formData.append("code", access_code);

            axios.post("https://discord.com/api/oauth2/token", formData)
                .then((res) => {
                    const { access_token, refresh_token, expires_in } = res.data;

                    resolve({
                        access_token,
                        refresh_token,
                        expires: Date.now() + expires_in * 1000
                    });
                })
                .catch(reject);
        }
    )
}

export function getDiscordUser(token: string): Promise<DiscordUser> {
    return new Promise(
        (resolve, reject) => {
            axios.get("https://discord.com/api/users/@me", {
                headers: {
                    Authorization: `Bearer ${token}`
                }
            })
                .then(
                    (res) => {
                        resolve(res.data);
                    }
                )
                .catch(reject);
        }
    )
}

export async function discordLogin(request: Request, code: string): Promise<Response> {
    return new Promise(
        (resolve, reject) => {
            getAccessToken(code)
                .then((token) => {
                    getDiscordUser(token.access_token)
                        .then(async (user) => {
                            prisma.discordUser.upsert({
                                create: {
                                    discord_id: user.id,
                                    access_token: token.access_token,
                                    refresh_token: token.refresh_token,
                                    expires: new Date(token.expires),
                                    username: user.username,
                                    discriminator: user.discriminator,
                                },
                                update: {
                                    discord_id: user.id,
                                    access_token: token.access_token,
                                    refresh_token: token.refresh_token,
                                    expires: new Date(token.expires),
                                    username: user.username,
                                    discriminator: user.discriminator,
                                },
                                where: {
                                    discord_id: user.id
                                }
                            })
                            .then(async () => {
                                resolve(await createUserSession({request, discord_id: user.id, redirectTo: '/'}));
                            })
                        })
                })
        }
    )
}