using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Shapes;

namespace GraphingCalculator.Controls
{
    /// <summary>
    /// Interaction logic for LimitWindow.xaml
    /// </summary>
    public partial class IntegralWindow : Window
    {
        #region Properties
        public string ExpressionString
        {
            get { return inputExpression.Text; }
            set { inputExpression.Text = value; }
        }
        #endregion

        #region Constructors
        public IntegralWindow()
        {
            InitializeComponent();
            ExpressionString = "";
        }

        public IntegralWindow(string expression)
        {
            InitializeComponent();
            ExpressionString = expression;
        }
        #endregion

        #region Other routines
        private void Result (string result, bool error = false)
        {
            outputResult.Text = result;
            if (error) outputResult.Foreground = Brushes.DarkRed;
            else outputResult.Foreground = Brushes.Black;
        }
        #endregion

        #region Button handlers
        private void buttonClose_Click(object sender, RoutedEventArgs e)
        {
            this.Close();
        }

        private void buttonCalculate_Click(object sender, RoutedEventArgs e)
        {
            double val_beg, val_end, integr_res;
            Expression beg, end, expr;
            beg = new Expression(inputIntervalBeg.Text);
            end = new Expression(inputIntervalEnd.Text);
            expr = new Expression(inputExpression.Text);
            
            // Try to evaluate interval ends
            try { val_beg = beg.Evaluate(); }
            catch { Result("Failed to evaluate interval start.", true); return; }

            try { val_end = end.Evaluate(); }
            catch { Result("Failed to evaluate interval end.", true); return; }

            // Try to calculate the integral
            try { integr_res = Integrator.Integrate(expr, val_beg, val_end, "x"); }
            catch (Exception ex)
            {
                Result("Failed to evaluate expression. Message: " + ex.Message, true);
                Log.LogEvent("Failed to integrate expression: {0}", expr.ExpressionString);
                Log.LogEvent("> Interval: [{0}, {1}] = [{2}, {3}]", beg.ExpressionString, end.ExpressionString, val_beg, val_end);
                Log.LogEvent("> Message: {0}", ex.Message);
                Log.LogEvent("> Stack trace: {0}", ex.StackTrace);
                return;
            }

            // Show result
            Result(Math.Round(integr_res, 14).ToString());
            Log.LogEvent("Integrated expression: {0}", expr.ExpressionString);
            Log.LogEvent("> Interval: [{0}, {1}] = [{2}, {3}]", beg.ExpressionString, end.ExpressionString, val_beg, val_end);
            Log.LogEvent("> Result: {0}", integr_res);
        }
        #endregion
    }
}