using System.Globalization;
using AMREZ.EOP.Abstractions.Applications.UseCases.Payments.SlipVerification;
using AMREZ.EOP.Abstractions.Applications.UseCases.Payments.SlipVerification.QrDecode;
using AMREZ.EOP.Abstractions.Infrastructures.Integrations.SCB.Clients;
using AMREZ.EOP.Application.UseCases.Payments.SlipVerification.BankDetect;
using AMREZ.EOP.Application.UseCases.Payments.SlipVerification.QrDecode;
using AMREZ.EOP.Contracts.DTOs.Payments.SlipVerification;
using AMREZ.EOP.Domain.Shared.Payments;

namespace AMREZ.EOP.Application.UseCases.Payments.SlipVerification;

public sealed class VerifyFromImageUseCase : IVerifyFromImageUseCase
{
    private readonly IQrDecoder _qr;
    private readonly IScbSlipClient _scb;
    private readonly SCBOptions _opts;

    public VerifyFromImageUseCase(IQrDecoder qr, IScbSlipClient scb, SCBOptions opts)
    {
        _qr = qr;
        _scb = scb;
        _opts = opts;
    }

    public async Task<VerifyFromImageResponse?> ExecuteAsync(VerifyFromImageRequest request, CancellationToken ct)
    {
        await using var ms = new MemoryStream();
        await request.Image.CopyToAsync(ms, ct);

        var qrText  = _qr.TryDecodeText(ms.ToArray());
        var transId = TransRefParser.TryExtract(qrText);
        var bank    = ParserBankDetect.FromQrText(qrText) ?? _opts.DefaultSendingBank;

        if (string.IsNullOrWhiteSpace(transId)) return null; // ไม่มี id ก็หยุด

        // ← SCB API ต้องการ “id” (transRef/txnId) + sendingBank เท่านั้น
        var env = await _scb.VerifyAsync(transId, bank, ct);
        if (env?.Status?.Code != 1000 || env.Data is null) return null;

        // 3) map → controller response
        var d = env.Data;
        var amount = decimal.TryParse(d.PaidLocalAmount ?? d.Amount ?? "0", NumberStyles.Any,
            CultureInfo.InvariantCulture, out var v)
            ? v
            : 0m;
        var when = CombineBangkok(d.TransDate, d.TransTime);

        var msisdn = d.Sender?.Proxy?.Type == "MSISDN" ? d.Sender.Proxy.Value : null;
        var biller = d.Receiver?.Proxy?.Type == "BILLERID" ? d.Receiver.Proxy.Value : null;

        return new VerifyFromImageResponse
        {
            TransRef = d.TransRef ?? transId,
            SendingBank = bank,
            AmountTHB = amount,
            CurrencyNumeric = d.PaidLocalCurrency ?? "764",
            SenderMsisdn = msisdn,
            BillerId = biller,
            TransactedAt = when
        };
    }

    private static DateTimeOffset CombineBangkok(string? date, string? time)
    {
        if (string.IsNullOrWhiteSpace(date) || string.IsNullOrWhiteSpace(time))
            return DateTimeOffset.UtcNow; // fallback

        var dt = DateTime.ParseExact($"{date} {time}", "yyyyMMdd HH:mm:ss", CultureInfo.InvariantCulture);
        var local = DateTime.SpecifyKind(dt, DateTimeKind.Unspecified);

        TimeZoneInfo? tz = null;
        try
        {
            tz = TimeZoneInfo.FindSystemTimeZoneById("Asia/Bangkok");
        }
        catch
        {
        }

        if (tz is null)
            try
            {
                tz = TimeZoneInfo.FindSystemTimeZoneById("SE Asia Standard Time");
            }
            catch
            {
            }

        return tz is null
            ? new DateTimeOffset(local, TimeSpan.FromHours(7))
            : new DateTimeOffset(local, tz.GetUtcOffset(local));
    }
}