//--------------------------------------------------------------------------
// Object Scripting
// Copyright (c) 1996, 1997 by Borland International, All Rights Reserved
//
// ALIGNEQ.SPP: Align at Equals. Aligns a block of assignments by
//   positioning the equals operators one space after the longest lvalue
//   in the current block.
//
// USE: Select a group of assignments. Run script.
//
// FILES: MSG.SPP
//
// History:
//  6:8:97  Doesn't split up <= >= += etc operators - ignores lines with these on
//--------------------------------------------------------------------------
print typeid(module());

//
// IDE imports.
//
import IDE;
import scriptEngine;
import editor;

//
// Load support module(s).
//
if (!scriptEngine.IsLoaded("msg")) scriptEngine.Load("msg");

aligneq()
{
  declare msg     = new TMsg();
  declare sTmp    = new String();
  declare curView = editor.TopView;

  // Validate current block.
  //
  if (!curView.Block.IsValid) {
    msg.Info("There is no valid current block.");
    return;
  }

  //
  // Get each line of the block and remove redundant spaces prior to
  // the equal sign. Track the right-most occurrence of "=".
  //
  declare rowStart = curView.Block.StartingRow;
  declare rowEnd   = curView.Block.EndingRow;
  if (curView.Block.EndingColumn <= 1)  // if selection finishes at start of a line
     rowEnd--;                          // don't align equals on ending line

  declare farEqualsPos = 0;
  declare assignments = new array[];
  for (declare i = rowStart; i < rowEnd + 1; i++) {
    curView.Position.Move(i, 1);
    sTmp.Text = curView.Position.Read();
    sTmp.Text = RemoveRedundantSpacesBeforeEquals(sTmp.Text);
    declare ThisEqualsPos = sTmp.Index("=");
    // check that = is not preceded by one of "<>-+", ignore if it is
    if (ThisEqualsPos > farEqualsPos) // found equals at a later column
        if (ThisEqualsPos >1)       // might have operator preceeding it
        {
           declare Char = sTmp.SubString(ThisEqualsPos-2, 1).Text;   // get preceeding character
           if ((Char != "<") && (Char != ">") && (Char != "-") && (Char != "!") &&
               (Char != "+") && (Char != "^") && (Char != "&") && (Char != "|"))
               farEqualsPos = ThisEqualsPos;    // save column of last equals found
        }
        else
           farEqualsPos = ThisEqualsPos;    // save column of last equals found
    assignments[i - rowStart] = sTmp.Text;
  }

  // Pad the lines to align them at the farthest equals location.
  //
  for (declare i = 0; initialized(assignments[i]); i++) {
    sTmp.Text = assignments[i];
    declare equalsPos = sTmp.Index("=");
    if (equalsPos > 1 && equalsPos < farEqualsPos)
    {
        declare Char = sTmp.SubString(equalsPos-2, 1).Text;   // get preceeding character
        if ((Char != "<") && (Char != ">") && (Char != "-") && (Char != "!") &&
               (Char != "+") && (Char != "^") && (Char != "&") && (Char != "|"))
        {
            assignments[i] = sTmp.SubString(0, equalsPos - 1).Text +
                       Spaces(farEqualsPos - equalsPos) +
                       sTmp.SubString(equalsPos - 1).Text;
        }
    }
  }

  // Swap in the new lines.
  //
  for (declare i = rowStart; i < rowEnd + 1; i++) {
    with (curView) {
      .Position.Move(i, 1);
      .Block.Extend(i + 1, 1);
      .Block.Delete();
      .Position.Move(i, 1);
      .Position.InsertText(assignments[i - rowStart]);
    }
  }
}

//
// Returns the specified string with spaces between the identifier and
// the equals sign removed.
//
RemoveRedundantSpacesBeforeEquals(line)
{
  // Cut out a space for each two spaces before the equals sign.
  //
  declare sLine = new String(line);
  declare eqPos = sLine.Index("=");
  while (sLine.SubString(eqPos - 3, 2).Text == "  ") {
    sLine.Text = sLine.SubString(0, eqPos - 2).Text +
                 sLine.SubString(eqPos - 1).Text;
    eqPos--;
  }

  return sLine.Text;
}

//
// Returns a string of count spaces long.
//
Spaces(count)
{
  declare spaces ="";
  for (declare i = 0; i < count; i++) {
    spaces += " ";
  }
  return spaces;
}