using BakeryErp.Infrastructure.Database;
using BakeryErp.Infrastructure.Repositories;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;

namespace BakeryErp.Web.Pages;

public sealed class InventoryModel : PageModel
{
    private readonly InventoryRepository _inventoryRepository;
    private readonly MasterDataLookupRepository _lookupRepository;

    public InventoryModel(InventoryRepository inventoryRepository, MasterDataLookupRepository lookupRepository)
    {
        _inventoryRepository = inventoryRepository;
        _lookupRepository = lookupRepository;
    }

    [BindProperty]
    public LocalInventoryTransaction Form { get; set; } = new()
    {
        TransactionType = LocalInventoryTransactionType.GoodsReceipt,
        Unit = "kg"
    };

    [BindProperty]
    public string? OccurredDateText { get; set; }

    [TempData]
    public string? Message { get; set; }

    [TempData]
    public string? ErrorMessage { get; set; }

    public IReadOnlyList<LocalStockBalance> StockBalances { get; private set; } = [];
    public IReadOnlyList<LocalInventoryTransaction> Transactions { get; private set; } = [];
    public IReadOnlyList<LookupOption> WarehouseOptions { get; private set; } = [];
    public IReadOnlyList<ItemLookupOption> ItemOptions { get; private set; } = [];
    public InventoryReport Report { get; private set; } = new(0, 0, 0, 0, 0);

    public IReadOnlyList<LocalInventoryTransactionType> TransactionTypeOptions { get; } =
    [
        LocalInventoryTransactionType.GoodsReceipt,
        LocalInventoryTransactionType.StockOut,
        LocalInventoryTransactionType.StockAdjustment,
        LocalInventoryTransactionType.Scrap,
        LocalInventoryTransactionType.StoreReturn
    ];

    public void OnGet(Guid? editId)
    {
        LoadPageData();

        if (editId is null)
        {
            Form = new LocalInventoryTransaction
            {
                TransactionNumber = $"INV-{DateTime.Today:yyyyMMdd}-{Transactions.Count + 1:000}",
                TransactionType = LocalInventoryTransactionType.GoodsReceipt,
                OccurredAt = DateTime.UtcNow,
                Unit = "kg"
            };
            OccurredDateText = DateTime.Today.ToString("yyyy-MM-dd");
            return;
        }

        Form = _inventoryRepository.FindTransaction(editId.Value) ?? new LocalInventoryTransaction();
        OccurredDateText = Form.OccurredAt.ToLocalTime().ToString("yyyy-MM-dd");
    }

    public IActionResult OnPostSave()
    {
        Form.OccurredAt = ParseOccurredAt();

        var result = _inventoryRepository.SaveTransaction(Form);
        if (!result.IsSuccess)
        {
            ErrorMessage = result.ErrorMessage;
            return RedirectToPage();
        }

        Message = "庫存異動已儲存，等待審核入帳。";
        return RedirectToPage();
    }

    public IActionResult OnPostApprove(Guid id)
    {
        var result = _inventoryRepository.Approve(id);
        if (!result.IsSuccess)
        {
            ErrorMessage = result.ErrorMessage;
            return RedirectToPage();
        }

        Message = "庫存異動已審核並更新即時庫存。";
        return RedirectToPage();
    }

    public IActionResult OnPostCancel(Guid id)
    {
        _inventoryRepository.Cancel(id);
        Message = "庫存異動已取消。";
        return RedirectToPage();
    }

    public string GetStatusClass(LocalInventoryTransactionStatus status)
    {
        return status switch
        {
            LocalInventoryTransactionStatus.Approved => "ok",
            LocalInventoryTransactionStatus.PendingApproval => "warn",
            LocalInventoryTransactionStatus.Cancelled => "off",
            _ => "info"
        };
    }

    private DateTime ParseOccurredAt()
    {
        return DateOnly.TryParse(OccurredDateText, out var date)
            ? date.ToDateTime(TimeOnly.MinValue).ToUniversalTime()
            : DateTime.UtcNow;
    }

    private void LoadPageData()
    {
        StockBalances = _inventoryRepository.ListBalances();
        Transactions = _inventoryRepository.ListTransactions();
        WarehouseOptions = _lookupRepository.Warehouses();
        ItemOptions = _lookupRepository.Items();
        Report = _inventoryRepository.GetReport();
    }
}