#region Using directives

using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Drawing.Printing;
using System.IO;
using System.Windows.Forms;

#endregion

namespace UsefulPrintingTechniquesSample {

  public partial class MainForm : Form {

    [System.Runtime.InteropServices.DllImport("gdi32.dll")]
    static extern int GetDeviceCaps(IntPtr hdc, DeviceCapsIndex index);

    enum DeviceCapsIndex {
      PhysicalOffsetX = 112,
      PhysicalOffsetY = 113,
    }


    int pageCount;
    int rowCount;

    Font headerFont;
    Font textFont;

    List<String> fileRows = new List<string>(); // Data file
    bool preview;

    public MainForm() {

      InitializeComponent();

      // "Load" input file
      for( int i = 1; i <= 40; ++i ) {
        fileRows.Add(i.ToString() + ": The quick brown fox jumped over the lazy old dog.");
      }

      // Preview input file
      this.printPreviewControl.InvalidatePreview();
    }

    Hashtable pageSettings = new Hashtable();

    private void MainForm_Load(object sender, EventArgs e) {

      // Get initial page count
      this.previewPageNumericUpDown.Maximum = PageCountPrintController.GetPageCount(this.printDocument);
    }

    private void printDocument_BeginPrint(object sender, PrintEventArgs e) {

      // Don't print if nothing to print
      if( fileRows == null ) e.Cancel = true;

      // Print preview?
      preview = (e.PrintAction == PrintAction.PrintToPreview);

      // Pre-printing configuration
      this.pageCount = 1;
      this.rowCount = 0;
      this.headerFont = new Font("Arial", 50);
      this.textFont = new Font("Arial", 25);
    }
    private void printDocument_QueryPageSettings(object sender, QueryPageSettingsEventArgs e) {
      // Get page settings for the page that's currently printing
      PageSettings pageCountSettings = (PageSettings)pageSettings[pageCount];
      if( pageCountSettings != null ) {
        e.PageSettings = pageCountSettings;
      }
      else e.PageSettings = new PageSettings();
    }
    private void printDocument_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e) {

      Graphics g = e.Graphics;

      // Print page header
      // NOTE: This code simply prints a page number to the header,
      // the top margin, minus the left and right margins.
      string headerText = "Page " + this.pageCount;
      Rectangle marginBounds = GetRealMarginBounds(e, preview);
      RectangleF headerArea = new RectangleF(marginBounds.Left, 0, marginBounds.Width, marginBounds.Top);
      using( StringFormat format = new StringFormat() ) {
        format.LineAlignment = StringAlignment.Center;
        g.DrawString(headerText, headerFont, Brushes.Black, headerArea, format);
      }

      // Print page text
      // NOTE: This code prints line-by-line to an area that starts within 
      // the e.MarginBounds, which reduces each time a line is printed 
      // until no more text fits
      // NOTE: The PrintPageEventArgs.PrintAction property could tell us whether this is a preview
      // or not, which would be a great way to determine the preview property, vs 
      // having a class-wide field
      Rectangle printableArea = GetRealMarginBounds(e, preview);

      while( this.rowCount < fileRows.Count ) {

        string line = fileRows[rowCount];

        // Get size for wordwrap
        SizeF printSize = g.MeasureString(line, this.textFont, printableArea.Width);

        if( printableArea.Height > printSize.Height ) {

          // Print line
          g.DrawString(line, this.textFont, Brushes.Black, printableArea);

          // Calculate and reduce remaining printable area
          printableArea.Y += (int)printSize.Height;
          printableArea.Height -= (int)printSize.Height;

          this.rowCount++;
        }
        else break;
      }

      // Increment page count
      this.pageCount++;

      // Keep printing while more rows
      e.HasMorePages = (this.rowCount < fileRows.Count);

    }
    private void printDocument_EndPrint(object sender, PrintEventArgs e) {
      // Post-printing cleanup
      this.textFont.Dispose();
      this.headerFont.Dispose();
    }

    private void printButton_Click(object sender, EventArgs e) {
      this.printDialog.AllowSomePages = true;
      this.printDialog.PrinterSettings = this.printDocument.PrinterSettings;
      this.printDialog.PrinterSettings.FromPage = 1;
      this.printDialog.PrinterSettings.ToPage = PageCountPrintController.GetPageCount(this.printDocument);

      DialogResult result = this.printDialog.ShowDialog();
      // BUG: Autozoom doesn't work either
      if( result != DialogResult.Cancel ) {
        this.printDocument.PrinterSettings = this.printDialog.PrinterSettings;
        this.printDocument.Print();
      }
    }
    private void previewPageNumericUpDown_ValueChanged(object sender, EventArgs e) {
      // Go to specified print preview page
      this.printPreviewControl.StartPage = (int)this.previewPageNumericUpDown.Value - 1;
    }
    private void editPageSettingsButton_Click(object sender, EventArgs e) {

      // Set page setup dialog with page settings for current page
      PageSettings pageCountSettings = (PageSettings)pageSettings[(int)this.previewPageNumericUpDown.Value];
      if( pageCountSettings != null ) {
        this.pageSetupDialog.PageSettings = pageCountSettings;
      }
      else this.pageSetupDialog.PageSettings = new PageSettings();

      // Edit page settings
      if( this.pageSetupDialog.ShowDialog() == DialogResult.OK ) {

        // Store new page settings and apply
        pageSettings[(int)this.previewPageNumericUpDown.Value] = (PageSettings)this.pageSetupDialog.PageSettings.Clone();
        this.printPreviewControl.InvalidatePreview();

        // Update page count to reflect document changes
        this.previewPageNumericUpDown.Maximum = PageCountPrintController.GetPageCount(this.printDocument);
      }
    }
    private void getPageCountButton_Click(object sender, EventArgs e) {
      MessageBox.Show(PageCountPrintController.GetPageCount(this.printDocument).ToString());
    }

    // Adjust MarginBounds rectangle when printing based
    // on the physical characteristics of the printer
    static Rectangle GetRealMarginBounds(PrintPageEventArgs e, bool preview) {
      if( preview ) return e.MarginBounds;

      int cx = 0;
      int cy = 0;
      IntPtr hdc = e.Graphics.GetHdc();

      try {
        // Both of these come back as device units and are not
        // scaled to 1/100th of an inch
        cx = GetDeviceCaps(hdc, DeviceCapsIndex.PhysicalOffsetX);
        cy = GetDeviceCaps(hdc, DeviceCapsIndex.PhysicalOffsetY);
      }
      finally {
        e.Graphics.ReleaseHdc(hdc);
      }

      // Create the real margin bounds by scaling the offset
      // by the printer resolution and then rescaling it
      // back to 1/100th of an inch
      Rectangle marginBounds = e.MarginBounds;
      int dpiX = (int)e.Graphics.DpiX;
      int dpiY = (int)e.Graphics.DpiY;
      marginBounds.Offset(-cx * 100 / dpiX, -cy * 100 / dpiY);
      return marginBounds;
    }

    private void previewButton_Click(object sender, EventArgs e) {
      this.printPreviewDialog.ShowDialog();
    }
  }
}