using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Text;
using System.Windows.Forms;
using HeuristicLab.Data;
using HeuristicLab.Encodings.SymbolicExpressionTreeEncoding;

namespace HeuristicLab.Problems.DataAnalysis.Symbolic.Views {
  public partial class InsertNodeDialog : Form {
    public string Caption {
      get { return this.Text; }
      set {
        if (InvokeRequired)
          Invoke(new Action<string>(x => this.Caption = x), value);
        else
          this.Text = value;
      }
    }

    public InsertNodeDialog() {
      InitializeComponent();
    }

    public void SetAllowedSymbols(IEnumerable<ISymbol> symbols) {
      allowedSymbolsCombo.Items.Clear();
      foreach (var s in symbols) allowedSymbolsCombo.Items.Add(s);
      allowedSymbolsCombo.SelectedIndex = 0;
    }

    public ISymbol SelectedSymbol() {
      return (ISymbol)allowedSymbolsCombo.SelectedItem;
    }

    private void allowedSymbolsCombo_SelectedIndexChanged(object sender, EventArgs e) {
      var combo = (ComboBox)sender;
      var symbol = combo.Items[combo.SelectedIndex];
      if (symbol is Constant) {
        // add controls to the dialog for changing the constant value
        variableNameLabel.Visible = false;
        variableNamesCombo.Visible = false;
        variableWeightLabel.Visible = false;
        variableWeightTextBox.Visible = false;
        constantValueLabel.Visible = true;
        constantValueTextBox.Visible = true;
      } else if (symbol is Variable) {
        var variable = (Variable)symbol;
        foreach (var name in variable.VariableNames) variableNamesCombo.Items.Add(name);
        variableNamesCombo.SelectedIndex = 0;
        variableNameLabel.Visible = true;
        variableNamesCombo.Visible = true;
        variableWeightLabel.Visible = true;
        variableWeightTextBox.Visible = true;
        constantValueLabel.Visible = false;
        constantValueTextBox.Visible = false;
        // add controls to the dialog for changing the variable name or weight
      }
    }

    // validation
    private void variableWeightTextBox_Validating(object sender, CancelEventArgs e) {
      string errorMessage;
      if (ValidateDoubleValue(variableWeightTextBox.Text, out errorMessage)) return;
      e.Cancel = true;
      errorProvider.SetError(variableWeightTextBox, errorMessage);
      variableWeightTextBox.SelectAll();
    }

    private void constantValueTextBox_Validating(object sender, CancelEventArgs e) {
      string errorMessage;
      if (ValidateDoubleValue(constantValueTextBox.Text, out errorMessage)) return;
      e.Cancel = true;
      errorProvider.SetError(constantValueTextBox, errorMessage);
      constantValueTextBox.SelectAll();
    }

    private static bool ValidateDoubleValue(string value, out string errorMessage) {
      double val;
      bool valid = double.TryParse(value, out val);
      errorMessage = string.Empty;
      if (!valid) {
        var sb = new StringBuilder();
        sb.Append("Invalid Value (Valid Value Format: \"");
        sb.Append(FormatPatterns.GetDoubleFormatPattern());
        sb.Append("\")");
        errorMessage = sb.ToString();
      }
      return valid;
    }

    public event EventHandler DialogValidated;

    private void childControl_KeyDown(object sender, KeyEventArgs e) {
      insertNodeDialog_KeyDown(sender, e);
    }

    private void insertNodeDialog_KeyDown(object sender, KeyEventArgs e) {
      if (e.KeyCode == Keys.Enter || e.KeyCode == Keys.Return) {
        if (ValidateChildren()) {
          DialogValidated(this, e);
          Close();
        }
      }
    }
  }
}