/*
	Spacebar: A FOSS re-implementation and extension of the Discord.com backend.
	Copyright (C) 2023 Spacebar and Spacebar Contributors

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU Affero General Public License as published
	by the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU Affero General Public License for more details.

	You should have received a copy of the GNU Affero General Public License
	along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

import { Column, CreateDateColumn, Entity, FindOptionsWhere, Index, JoinColumn, OneToOne, RelationId } from "typeorm";
import { BaseClass } from "./BaseClass";

@Entity({
    name: "instance_bans",
})
export class InstanceBan extends BaseClass {
    @Column({ type: "bigint" })
    @CreateDateColumn()
    created_at: Date = new Date();

    @Column()
    reason: string;

    @Index("IDX_instance_ban_user_id", { type: "hash" })
    @Column({ type: "int8", nullable: true })
    user_id?: string;

    @Index("IDX_instance_ban_fingerprint", { type: "hash" })
    @Column({ nullable: true })
    fingerprint?: string;

    @Index("IDX_instance_ban_ip_address", { type: "hash" })
    @Column({ nullable: true })
    ip_address?: string;

    // chain of trust type tracking

    @Column({ default: false })
    is_allowlisted: boolean = false;

    @Column({ default: false })
    is_from_other_instance_ban: boolean = false;

    @Column({ nullable: true })
    @RelationId((instance_ban: InstanceBan) => instance_ban.origin_instance_ban)
    origin_instance_ban_id?: string;

    @JoinColumn({ name: "origin_instance_ban_id", foreignKeyConstraintName: "FK_origin_instance_ban_id" })
    @OneToOne(() => InstanceBan, { nullable: true, onDelete: "SET NULL" })
    origin_instance_ban?: InstanceBan;

    static async findInstanceBans(opts: { userId?: string; ipAddress?: string; fingerprint?: string; propagateBan?: boolean }) {
        const optionalChecks: FindOptionsWhere<InstanceBan>[] = [{ user_id: opts.userId }];
        if (opts?.ipAddress) optionalChecks.push({ ip_address: opts.ipAddress });
        if (opts?.fingerprint) optionalChecks.push({ fingerprint: opts.fingerprint });
        const instanceBans = await InstanceBan.find({ where: optionalChecks });

        const banReasons = [];
        for (const ban of instanceBans) {
            if (ban.is_allowlisted) continue;
            if (opts?.fingerprint && ban.fingerprint === opts.fingerprint) banReasons.push("fingerprint");
            if (opts?.ipAddress && ban.ip_address === opts.ipAddress) banReasons.push("ipAddress");
            if (opts?.userId && ban.user_id === opts?.userId) banReasons.push("userId");
        }

        const banViralityPromises: Promise<InstanceBan>[] = [];
        if (opts.propagateBan && banReasons.length > 0) {
            if (opts?.ipAddress && !instanceBans.find((b) => b.ip_address === opts.ipAddress))
                banViralityPromises.push(
                    InstanceBan.create({
                        user_id: opts.userId,
                        ip_address: opts.ipAddress,
                        reason: "Propagated from other instance ban",
                        is_from_other_instance_ban: true,
                        origin_instance_ban: instanceBans[0],
                    }).save(),
                );
            if (opts?.fingerprint && !instanceBans.find((b) => b.fingerprint === opts.fingerprint))
                banViralityPromises.push(
                    InstanceBan.create({
                        user_id: opts.userId,
                        fingerprint: opts.fingerprint,
                        reason: "Propagated from other instance ban",
                        is_from_other_instance_ban: true,
                        origin_instance_ban: instanceBans[0],
                    }).save(),
                );
            if (opts?.userId && !instanceBans.find((b) => b.user_id === opts.userId))
                banViralityPromises.push(
                    InstanceBan.create({
                        user_id: opts.userId,
                        reason: "Propagated from other instance ban",
                        is_from_other_instance_ban: true,
                        origin_instance_ban: instanceBans[0],
                    }).save(),
                );
        }

        await Promise.all(banViralityPromises);
        return banReasons;
    }
}