import { Injectable } from '@nestjs/common';
import { PrismaService } from '../prisma/prisma.service';

interface DisputeFilter {
    page: number;
    limit: number;
    status?: string;
}

@Injectable()
export class DisputesService {
    constructor(private prisma: PrismaService) { }

    async list(filter: DisputeFilter) {
        const offset = (filter.page - 1) * filter.limit;
        let whereClause = '';
        if (filter.status) {
            whereClause = `WHERE status = '${filter.status}'`;
        }

        const disputes = await this.prisma.$queryRawUnsafe<any[]>(`
            SELECT d.*, 
                   o.id as order_id, 
                   o.total_cents,
                   buyer.name as buyer_name,
                   seller.corporate_name as seller_name
            FROM disputes d
            LEFT JOIN orders o ON d.order_id = o.id
            LEFT JOIN users buyer ON d.buyer_id = buyer.id
            LEFT JOIN companies seller ON d.seller_id = seller.id
            ${whereClause}
            ORDER BY d.created_at DESC
            LIMIT ${filter.limit} OFFSET ${offset}
        `);

        const countResult = await this.prisma.$queryRawUnsafe<[{ count: bigint }]>(`
            SELECT COUNT(*) as count FROM disputes ${whereClause}
        `);

        return {
            disputes,
            total: Number(countResult[0]?.count || 0),
            page: filter.page,
            limit: filter.limit,
        };
    }

    async getById(id: string) {
        const disputes = await this.prisma.$queryRaw<any[]>`
            SELECT d.*, 
                   o.id as order_id,
                   o.total_cents,
                   o.status as order_status,
                   buyer.name as buyer_name,
                   buyer.email as buyer_email,
                   seller.corporate_name as seller_name
            FROM disputes d
            LEFT JOIN orders o ON d.order_id = o.id
            LEFT JOIN users buyer ON d.buyer_id = buyer.id
            LEFT JOIN companies seller ON d.seller_id = seller.id
            WHERE d.id = ${id}::uuid
        `;
        return disputes[0] || null;
    }

    async create(data: {
        orderId: string;
        buyerId: string;
        sellerId: string;
        reason: string;
        description: string;
    }) {
        await this.prisma.$executeRaw`
            INSERT INTO disputes (id, order_id, buyer_id, seller_id, reason, description, status, created_at, updated_at)
            VALUES (
                gen_random_uuid(),
                ${data.orderId}::uuid,
                ${data.buyerId}::uuid,
                ${data.sellerId}::uuid,
                ${data.reason},
                ${data.description},
                'open',
                NOW(),
                NOW()
            )
        `;
        return { status: 'created' };
    }

    async resolve(id: string, data: {
        resolution: string;
        refundAmountCents?: number;
        notes: string;
    }) {
        await this.prisma.$executeRaw`
            UPDATE disputes
            SET status = 'resolved',
                resolution = ${data.resolution},
                refund_amount_cents = ${data.refundAmountCents || 0},
                admin_notes = ${data.notes},
                resolved_at = NOW(),
                updated_at = NOW()
            WHERE id = ${id}::uuid
        `;
        return { status: 'resolved' };
    }
}