using Application.Abstractions.Data;
using Application.Abstractions.Messaging;
using Application.Abstractions.Messaging.Email;
using Application.Common;
using Domain.Entities.EmailVerification;
using Domain.Entities.EmailVerification.ValueObject;
using SharedKernel.Results;
using Microsoft.EntityFrameworkCore;

namespace Application.Features.Api.MyPage.Withdraw.RequestCode;

internal sealed class Handler(
    IAppDbContext db,
    IMailService mailService
) : ICommandHandler<Command, Result>
{
    public async Task<Result> Handle(Command request, CancellationToken ct)
    {
        var member = await db.Member.FirstOrDefaultAsync(m => m.ID == request.MemberID, ct);
        if (member is null)
        {
            return Result.Failure(Error.NotFound("MyPage.MemberNotFound", "회원 정보를 찾을 수 없습니다."));
        }

        if (member.IsWithdraw)
        {
            return Result.Failure(Error.Problem("MyPage.AlreadyWithdrawn", "이미 탈퇴한 회원입니다."));
        }

        if (member.IsDenied)
        {
            return Result.Failure(Error.Problem("MyPage.MemberDenied", "차단된 회원은 이용할 수 없습니다."));
        }

        var email = member.Email;

        // 기존 미인증 코드 제거
        var existing = await db.EmailVerifyNumber.Where(e => e.Email == email && e.Type == VerificationType.Withdraw && !e.IsVerified).ToListAsync(ct);
        db.EmailVerifyNumber.RemoveRange(existing);

        // 6자리 코드 발급 (10분 만료)
        var code = Random.Shared.Next(100000, 999999).ToString();
        var verifyNumber = EmailVerifyNumber.Create(
            VerificationType.Withdraw,
            email,
            code,
            DateTime.UtcNow.AddMinutes(10)
        );

        await db.EmailVerifyNumber.AddAsync(verifyNumber, ct);
        await db.SaveChangesAsync(ct);

        // 이메일 발송 — WithdrawVerify 템플릿 우선, 없으면 hardcoded fallback
        var emailTpl = (await db.Config.AsNoTracking().FirstOrDefaultAsync(ct))?.EmailTemplate;
        var subject = string.IsNullOrWhiteSpace(emailTpl?.WithdrawVerifyEmailFormTitle)
            ? "회원탈퇴 인증번호"
            : emailTpl!.WithdrawVerifyEmailFormTitle!;
        var content = string.IsNullOrWhiteSpace(emailTpl?.WithdrawVerifyEmailFormContent)
            ? $"<p>회원탈퇴 인증번호입니다.</p><p><strong>{code}</strong></p><p>이 코드는 10분간 유효합니다.</p>"
            : emailTpl!.WithdrawVerifyEmailFormContent!.Render(("Code", code), ("Email", email));

        await mailService.SendAsync(new SendData(email, subject, content), ct);

        return Result.Success();
    }
}