using System;
using System.Linq;
using System.Threading;
using System.Windows.Forms;
using Tanshu.Accounts.Helpers;
using System.Collections.Generic;
using Tanshu.Accounts.BI;
using Tanshu.Accounts.Contracts;

namespace Tanshu.Accounts.PointOfSale
{
    public partial class UpdateForm : Form
    {
        private delegate decimal GetTextboxValueDelegate(TextBox textbox);
        private delegate decimal ProcessDelegate(DateTime startDate, DateTime endDate, decimal target, decimal tax);
        ProcessDelegate processDelegate;
        public UpdateForm()
        {
            InitializeComponent();
        }
        public void ShowProgress(decimal minimum, decimal total, decimal current, string message)
        {
            if (!txtStatus.InvokeRequired)
            {
                txtStatus.Text = string.Format("{0:#,###} / {1:#,###} :: {2}", current, total, message);
            }
            else
            {
                ShowProgessDelegate showProgress = new ShowProgessDelegate(ShowProgress);
                BeginInvoke(showProgress, new object[] { minimum, total, current, message });
            }
        }

        private void btnGo_Click(object sender, EventArgs e)
        {
            dtpFrom.Value = Convert.ToDateTime(string.Format("{0:dd-MMM-yyyy} 00:00:00", dtpFrom.Value));
            dtpTo.Value = Convert.ToDateTime(string.Format("{0:dd-MMM-yyyy} 23:59:59", dtpTo.Value));

            if (!Thread.CurrentPrincipal.IsInRole("Security/CreateUser"))
                return;
            RunUpdate(-1);
        }
        private void RunUpdate(decimal last)
        {
            processDelegate = new ProcessDelegate(Process);
            if (last == -1)
                processDelegate.BeginInvoke(dtpFrom.Value, dtpTo.Value, GetTextboxValue(txtTwelve), .125M, new AsyncCallback(CallbackMethod), null);
            if (last == .125M)
                processDelegate.BeginInvoke(dtpFrom.Value, dtpTo.Value, GetTextboxValue(txtFour), .04M, new AsyncCallback(CallbackMethod), null);
            if (last == .04M)
                processDelegate.BeginInvoke(dtpFrom.Value, dtpTo.Value, GetTextboxValue(txtZero), 0M, new AsyncCallback(CallbackMethod), null);
            if (last == 0M)
                new ManagementBI().Reorder(dtpFrom.Value, dtpTo.Value, ShowProgress);
        }
        private void CallbackMethod(IAsyncResult ar)
        {
            decimal tax = processDelegate.EndInvoke(ar);
            RunUpdate(tax);
        }
        private decimal GetTextboxValue(TextBox textbox)
        {
            if (!textbox.InvokeRequired)
            {
                decimal value;
                if (!decimal.TryParse(textbox.Text, out value))
                    value = 0;
                return value;
            }
            else
            {
                GetTextboxValueDelegate getTextboxValueDelegate = new GetTextboxValueDelegate(GetTextboxValue);
                return (decimal)Invoke(getTextboxValueDelegate, new object[] { textbox });
            }
        }
        private decimal Process(DateTime startDate, DateTime endDate, decimal target, decimal tax)
        {
            ShowProgress(0, 0, 0, string.Format("Starting work on {0:00.00%}. Target : {1:#,###}", tax, target));
            if (target == 0)
                return tax;
            ManagementBI man = new ManagementBI();
            List<Guid> list = man.GetUpdateBillList(tax, false, true, false, dtpFrom.Value, dtpTo.Value);
            int totalBills = list.Count;
            decimal existing = man.GetBalance(tax, dtpFrom.Value, dtpTo.Value);
            int i = 0;
            decimal work = existing / (existing - target);
            while ((existing > target) && (totalBills > 0))
            {
                int runner = Convert.ToInt32(Math.Floor(work * (i + 1) - i));
                if (runner < totalBills - 1)
                {
                    existing -= man.Update(list[runner + 1], tax, dtpFrom.Value, dtpTo.Value);
                    totalBills--;
                    i++;
                    list.Remove(list[runner + 1]);
                }
                else
                {
                    i = -1;
                    work = existing / (existing - target);
                }
                ShowProgress(0, target, existing, string.Format("Working on {0:00.00%}", tax));
            }
            ShowProgress(0, target, existing, string.Format("Finished {0:00.00%}", tax));
            return tax;
        }
    }
}