using System.Text;
using System.Text.Json;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;
using Microsoft.Extensions.Caching.Memory;
using MoneyMap.Controllers;
using MoneyMap.Models;
using MoneyMap.Services;
using MoneyMap.Tests.TestHelpers;

namespace MoneyMap.Tests.Controllers;

public class ImportsControllerTests
{
    [Fact]
    public async Task ImportCsv_AutoMode_SkipsDuplicates_AssignsCardAndCategory()
    {
        using var context = DbContextHelper.CreateInMemoryContext();
        SeedAutoImportData(context);

        var controller = CreateController(context);
        var csv = CreateCsvFormFile(
            "transactions.csv",
            "Date,Transaction,Name,Memo,Amount\n" +
            "2025-01-15,DEBIT,AMAZON MKTPL,existing usbank.com.1234,-50.00\n" +
            "2025-01-16,DEBIT,AMAZON MKTPL,new purchase usbank.com.1234,-25.00\n");

        var result = await controller.ImportCsv(new CsvImportRequest
        {
            Csv = csv,
            PaymentMode = MoneyMap.Models.Import.PaymentSelectMode.Auto
        });

        var ok = Assert.IsType<OkObjectResult>(result);
        using var json = JsonDocument.Parse(JsonSerializer.Serialize(ok.Value));

        Assert.Equal(2, json.RootElement.GetProperty("TotalRows").GetInt32());
        Assert.Equal(1, json.RootElement.GetProperty("Inserted").GetInt32());
        Assert.Equal(1, json.RootElement.GetProperty("SkippedDuplicates").GetInt32());
        Assert.Equal(2, json.RootElement.GetProperty("AutoCategorized").GetInt32());

        Assert.Equal(2, context.Transactions.Count());

        var imported = context.Transactions.Single(t => t.Memo == "new purchase usbank.com.1234");
        Assert.Equal(1, imported.AccountId);
        Assert.Equal(1, imported.CardId);
        Assert.Equal("Shopping", imported.Category);
    }

    [Fact]
    public async Task ImportCsv_AccountMode_ImportsWhenAutoDetectionIsUnavailable()
    {
        using var context = DbContextHelper.CreateInMemoryContext();
        context.Accounts.Add(new Account
        {
            Id = 7,
            Institution = "Manual Bank",
            Last4 = "4321",
            Owner = "Test Owner",
            AccountType = AccountType.Checking
        });
        await context.SaveChangesAsync();

        var controller = CreateController(context);
        var csv = CreateCsvFormFile(
            "manual-import.csv",
            "Date,Transaction,Name,Memo,Amount\n" +
            "2025-02-01,DEBIT,LOCAL STORE,no card info here,-10.00\n");

        var result = await controller.ImportCsv(new CsvImportRequest
        {
            Csv = csv,
            PaymentMode = MoneyMap.Models.Import.PaymentSelectMode.Account,
            SelectedAccountId = 7
        });

        var ok = Assert.IsType<OkObjectResult>(result);
        using var json = JsonDocument.Parse(JsonSerializer.Serialize(ok.Value));

        Assert.Equal(1, json.RootElement.GetProperty("Inserted").GetInt32());
        Assert.Equal(0, json.RootElement.GetProperty("SkippedDuplicates").GetInt32());

        var imported = Assert.Single(context.Transactions);
        Assert.Equal(7, imported.AccountId);
        Assert.Null(imported.CardId);
    }

    private static ImportsController CreateController(MoneyMap.Data.MoneyMapContext context)
    {
        var cardResolver = new CardResolver(context);
        var importer = new TransactionImporter(context, cardResolver);
        var categorizer = new TransactionCategorizer(context, new MemoryCache(new MemoryCacheOptions()));

        return new ImportsController(context, importer, categorizer);
    }

    private static void SeedAutoImportData(MoneyMap.Data.MoneyMapContext context)
    {
        context.Accounts.Add(new Account
        {
            Id = 1,
            Institution = "Test Bank",
            Last4 = "1234",
            Owner = "Test Owner",
            AccountType = AccountType.Checking
        });

        context.Cards.Add(new Card
        {
            Id = 1,
            Issuer = "Visa",
            Last4 = "1234",
            Owner = "Test Owner",
            AccountId = 1
        });

        context.CategoryMappings.Add(new CategoryMapping
        {
            Category = "Shopping",
            Pattern = "AMAZON",
            Priority = 10
        });

        context.Transactions.Add(new Transaction
        {
            Date = new DateTime(2025, 1, 15),
            TransactionType = "DEBIT",
            Name = "AMAZON MKTPL",
            Memo = "existing usbank.com.1234",
            Amount = -50.00m,
            Category = "Shopping",
            AccountId = 1,
            CardId = 1,
            Last4 = "1234"
        });

        context.SaveChanges();
    }

    private static IFormFile CreateCsvFormFile(string fileName, string content)
    {
        var bytes = Encoding.UTF8.GetBytes(content);
        var stream = new MemoryStream(bytes);
        return new FormFile(stream, 0, bytes.Length, "csv", fileName)
        {
            Headers = new HeaderDictionary(),
            ContentType = "text/csv"
        };
    }
}