
(********************************************************************)
(*                                                                  *)
(*  sydir7.sd7    Utility to synchronize directory trees            *)
(*  Copyright (C) 2009 - 2019  Thomas Mertes                        *)
(*                                                                  *)
(*  This program is free software; you can redistribute it and/or   *)
(*  modify it under the terms of the GNU General Public License as  *)
(*  published by the Free Software Foundation; either version 2 of  *)
(*  the License, or (at your option) any later version.             *)
(*                                                                  *)
(*  This program is distributed in the hope that it will be useful, *)
(*  but WITHOUT ANY WARRANTY; without even the implied warranty of  *)
(*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the   *)
(*  GNU General Public License for more details.                    *)
(*                                                                  *)
(*  You should have received a copy of the GNU General Public       *)
(*  License along with this program; if not, write to the           *)
(*  Free Software Foundation, Inc., 51 Franklin Street,             *)
(*  Fifth Floor, Boston, MA  02110-1301, USA.                       *)
(*                                                                  *)
(********************************************************************)


$ include "seed7_05.s7i";
  include "stdio.s7i";
  include "osfiles.s7i";
  include "time.s7i";
  include "duration.s7i";

const type: syncFlags is new struct
    var boolean: removeFilesAtDest is FALSE;
    var boolean: overwriteNewerDestFiles is FALSE;
    var boolean: doChanges is TRUE;
  end struct;


const proc: syncFile (in string: sourcePath, in string: destPath,
    in syncFlags: flags) is forward;


const proc: syncDir (in string: sourcePath, in string: destPath,
    in syncFlags: flags) is func
  local
    var array string: sourceContent is 0 times "";
    var array string: destContent is 0 times "";
    var boolean: updateMtime is FALSE;
    var integer: sourceIndex is 1;
    var integer: destIndex is 1;
    var string: sourceName is "";
    var string: destName is "";
  begin
    if getMTime(sourcePath) + 1 . SECONDS >= getMTime(destPath) then
      updateMtime := TRUE;
    end if;
    sourceContent := readDir(sourcePath);
    destContent := readDir(destPath);
    # writeln("syncDir " <& literal(sourcePath) <& " " <& literal(destPath));
    while sourceIndex <= length(sourceContent) and
        destIndex <= length(destContent) do
      sourceName := sourceContent[sourceIndex];
      destName := destContent[destIndex];
      if sourceName = destName then
        # writeln("syncFile = " <& literal(sourceName) <& " " <& literal(destName));
        syncFile(sourcePath & "/" & sourceName,
                 destPath & "/" & destName, flags);
        incr(sourceIndex);
        incr(destIndex);
      elsif sourceName < destName then
        # writeln("syncFile < " <& literal(sourceName) <& " " <& literal(destName));
        syncFile(sourcePath & "/" & sourceName,
                 destPath & "/" & sourceName, flags);
        incr(sourceIndex);
      else # sourceName > destName then
        # writeln("syncFile > " <& literal(sourceName) <& " " <& literal(destName));
        syncFile(sourcePath & "/" & destName,
                 destPath & "/" & destName, flags);
        incr(destIndex);
      end if;
    end while;
    while sourceIndex <= length(sourceContent) do
      sourceName := sourceContent[sourceIndex];
      # writeln("syncFile S " <& literal(sourceName));
      syncFile(sourcePath & "/" & sourceName,
               destPath & "/" & sourceName, flags);
      incr(sourceIndex);
    end while;
    while destIndex <= length(destContent) do
      destName := destContent[destIndex];
      # writeln("syncFile D " <& literal(destName));
      syncFile(sourcePath & "/" & destName,
               destPath & "/" & destName, flags);
      incr(destIndex);
    end while;
    if updateMtime then
      # writeln("update mtime " <& literal(sourcePath) <& " to " <& literal(destPath));
      if flags.doChanges then
        setMTime(destPath, getMTime(sourcePath));
      end if;
    end if;
  end func;


const func boolean: equalFileContent (in string: sourcePath, in string: destPath) is func
  result
    var boolean: equal is FALSE;
  local
    var file: sourceFile is STD_NULL;
    var file: destFile is STD_NULL;
    var string: sourceBlock is "";
    var string: destBlock is "";
  begin
    sourceFile := open(sourcePath, "r");
    if sourceFile <> STD_NULL then
      destFile := open(destPath, "r");
      if destFile <> STD_NULL then
        equal := TRUE;
        while equal and not eof(sourceFile) and not eof(destFile) do
          sourceBlock := gets(sourceFile, 134217728);
          destBlock := gets(destFile, 134217728);
          equal := sourceBlock = destBlock;
        end while;
        close(destFile);
      end if;
      close(sourceFile);
    end if;
  end func;


const proc: syncFile (in string: sourcePath, in string: destPath,
    in syncFlags: flags) is func
  local
    var fileType: sourceType is FILE_ABSENT;
    var fileType: destType is FILE_ABSENT;
    var time: sourceTime is time.value;
    var time: destTime is time.value;
    var array string: dirContent is 0 times "";
    var string: fileName is "";
  begin
    sourceType := fileTypeSL(sourcePath);
    destType := fileTypeSL(destPath);
    if sourceType = FILE_ABSENT then
      if destType <> FILE_ABSENT then
        if flags.removeFilesAtDest then
          writeln("remove file " <& literal(destPath));
          if flags.doChanges then
            removeTree(destPath);
          end if;
        end if;
      end if;
    elsif sourceType = FILE_SYMLINK then
      if destType = FILE_ABSENT then
        block
          if flags.doChanges then
            cloneFile(sourcePath, destPath);
          end if;
          writeln("copy symlink " <& literal(sourcePath) <& " to " <& literal(destPath));
        exception
          catch FILE_ERROR:
            writeln(" *** Cannot copy symlink " <& literal(sourcePath) <& " to " <& literal(destPath));
        end block;
      elsif destType = FILE_SYMLINK then
        if readlink(sourcePath) <> readlink(destPath) then
          writeln("Source link " <& literal(sourcePath) <&
                  " and destination link " <& literal(destPath) <&
                  " point to different paths");
        end if;
      else
        writeln(" *** Destination " <& literal(destPath) <& " is not a symbolic link");
      end if;
    elsif sourceType = FILE_DIR then
      if destType = FILE_ABSENT then
        writeln("copy directory " <& literal(sourcePath) <& " to " <& literal(destPath));
        if flags.doChanges then
          mkdir(destPath);
          syncDir(sourcePath, destPath, flags);
          setMTime(destPath, getMTime(sourcePath));
        end if;
      elsif destType = FILE_DIR then
        syncDir(sourcePath, destPath, flags);
      else
        writeln(" *** Destination " <& literal(destPath) <& " is not a directory");
      end if;
    elsif sourceType = FILE_REGULAR then
      if destType = FILE_ABSENT then
        block
          if flags.doChanges then
            cloneFile(sourcePath, destPath);
          end if;
          writeln("copy file " <& literal(sourcePath) <& " to " <& literal(destPath));
        exception
          catch FILE_ERROR:
            writeln(" *** Cannot copy file " <& literal(sourcePath) <& " to " <& literal(destPath));
        end block;
      elsif destType = FILE_REGULAR then
        sourceTime := getMTime(sourcePath);
        destTime := getMTime(destPath);
        # writeln(sourceTime);
        # writeln(destTime);
        if sourceTime > destTime + 1 . SECONDS then
          if fileSize(sourcePath) = fileSize(destPath) and equalFileContent(sourcePath, destPath) then
            writeln("Correct time of identical files " <& literal(sourcePath) <& " - " <& literal(destPath));
            if flags.doChanges then
              setMTime(destPath, sourceTime);
            end if;
          else
            writeln("update file " <& literal(sourcePath) <& " to " <& literal(destPath));
            if flags.doChanges then
              removeFile(destPath);
              cloneFile(sourcePath, destPath);
            end if;
          end if;
        elsif sourceTime < destTime - 1 . SECONDS then
          if fileSize(sourcePath) = fileSize(destPath) and equalFileContent(sourcePath, destPath) then
            writeln("Correct time of identical files " <& literal(sourcePath) <& " - " <& literal(destPath));
            if flags.doChanges then
              setMTime(destPath, sourceTime);
            end if;
          elsif flags.overwriteNewerDestFiles then
            writeln("replace newer dest file " <& literal(sourcePath) <& " to " <& literal(destPath));
            if flags.doChanges then
              removeFile(destPath);
              cloneFile(sourcePath, destPath);
            end if;
          else
            writeln(" *** Destination newer " <& literal(sourcePath) <& " - " <& literal(destPath));
            # writeln(sourceTime <& "   " <& destTime <& "   " <& destTime - 1 . SECONDS);
          end if;
        elsif fileSize(sourcePath) <> fileSize(destPath) then
          writeln("Correct file " <& literal(sourcePath) <& " to " <& literal(destPath));
          if flags.doChanges then
            removeFile(destPath);
            cloneFile(sourcePath, destPath);
          end if;
        end if;
      else
        writeln(" *** Destination " <& literal(destPath) <& " is not a regular file");
      end if;
    else
      writeln(" *** Source " <& literal(sourcePath) <& " has file type " <& sourceType);
    end if;
  end func;


const proc: main is func
  local
    var integer: numOfFileNames is 0;
    var string: parameter is "";
    var string: fromName is "";
    var string: toName is "";
    var boolean: error is FALSE;
    var syncFlags: flags is syncFlags.value;
  begin
    if length(argv(PROGRAM)) < 2 then
      writeln("Sydir7 Version 1.0 - Utility to synchronize directory trees");
      writeln("Copyright (C) 2009 - 2019 Thomas Mertes");
      writeln("This is free software; see the source for copying conditions.  There is NO");
      writeln("warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.");
      writeln("Sydir7 is written in the Seed7 programming language");
      writeln("Homepage: http://seed7.sourceforge.net");
      writeln;
      writeln("usage: sydir7 {-c|-n} source destination");
      writeln;
      writeln("Options:");
      writeln("  -c Copy files. Remove destination files, if they are missing in source.");
      writeln("     Overwrite newer destination files with older source files.");
      writeln("  -n No change. Write, what should be done to sync, but do not change");
      writeln("     anything.");
      writeln;
    else
      for parameter range argv(PROGRAM) do
        if startsWith(parameter, "-") then
          if parameter = "-c" then
            flags.removeFilesAtDest := TRUE;
            flags.overwriteNewerDestFiles := TRUE;
          elsif parameter = "-n" then
            flags.doChanges := FALSE;
          else
            writeln(" *** Unknown option: " <& parameter);
            error := TRUE;
          end if;
        else
          incr(numOfFileNames);
          case numOfFileNames of
            when {1}: fromName := convDosPath(parameter);
            when {2}: toName := convDosPath(parameter);
          end case;
        end if;
      end for;
      if numOfFileNames <> 2 then
        writeln(" *** Wrong number of parameters.");
        error := TRUE;
      end if;
      if not error then
        syncFile(fromName, toName, flags);
      end if;
    end if;
  end func;
