## Copyright (C) 2005-2012 S�ren Hauberg
## Copyright (C) 2010 VZLU Prague, a.s.
##
## This file is part of Octave.
##
## Octave 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 3 of the License, or (at
## your option) any later version.
##
## Octave 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 Octave; see the file COPYING.  If not, see
## <http://www.gnu.org/licenses/>.

## -*- texinfo -*-
## @deftypefn  {Function File} {} uninstall (@var{pkgnames}, @var{handle_deps}, 
## @var{verbose}, @var{local_list}, @var{global_list}, @var{global_install})
## Undocumented internal function.
## @end deftypefn

function uninstall (pkgnames, handle_deps, verbose, local_list,
                    global_list, global_install)
  ## Get the list of installed packages.
  [local_packages, global_packages] = installed_packages(local_list,
                                                         global_list);
  if (global_install)
    installed_pkgs_lst = {local_packages{:}, global_packages{:}};
  else
    installed_pkgs_lst = local_packages;
  endif

  num_packages = length (installed_pkgs_lst);
  delete_idx = [];
  for i = 1:num_packages
    cur_name = installed_pkgs_lst{i}.name;
    if (any (strcmp (cur_name, pkgnames)))
      delete_idx(end+1) = i;
    endif
  endfor

  ## Are all the packages that should be uninstalled already installed?
  if (length (delete_idx) != length (pkgnames))
    if (global_install)
      ## Try again for a locally installed package.
      installed_pkgs_lst = local_packages;

      num_packages = length (installed_pkgs_lst);
      delete_idx = [];
      for i = 1:num_packages
        cur_name = installed_pkgs_lst{i}.name;
        if (any (strcmp (cur_name, pkgnames)))
          delete_idx(end+1) = i;
        endif
      endfor
      if (length (delete_idx) != length (pkgnames))
        ## FIXME: We should have a better error message.
        warning ("some of the packages you want to uninstall are not installed");
      endif
    else
      ## FIXME: We should have a better error message.
      warning ("some of the packages you want to uninstall are not installed");
    endif
  endif

  ## Compute the packages that will remain installed.
  idx = setdiff (1:num_packages, delete_idx);
  remaining_packages = {installed_pkgs_lst{idx}};

  ## Check dependencies.
  if (handle_deps)
    error_text = "";
    for i = 1:length (remaining_packages)
      desc = remaining_packages{i};
      bad_deps = get_unsatisfied_deps (desc, remaining_packages);

      ## Will the uninstallation break any dependencies?
      if (! isempty (bad_deps))
        for i = 1:length (bad_deps)
          dep = bad_deps{i};
          error_text = cstrcat (error_text, " ", desc.name, " needs ",
                               dep.package, " ", dep.operator, " ",
                               dep.version, "\n");
        endfor
      endif
    endfor

    if (! isempty (error_text))
      error ("the following dependencies where unsatisfied:\n  %s", error_text);
    endif
  endif

  ## Delete the directories containing the packages.
  for i = delete_idx
    desc = installed_pkgs_lst{i};
    ## If an 'on_uninstall.m' exist, call it!
    if (exist (fullfile (desc.dir, "packinfo", "on_uninstall.m"), "file"))
      wd = pwd ();
      cd (fullfile (desc.dir, "packinfo"));
      on_uninstall (desc);
      cd (wd);
    endif
    ## Do the actual deletion.
    if (desc.loaded)
      rmpath (desc.dir);
      if (exist (getarchdir (desc)))
        rmpath (getarchdir (desc));
      endif
    endif
    if (exist (desc.dir, "dir"))
      [status, msg] = rm_rf (desc.dir);
      if (status != 1)
        error ("couldn't delete directory %s: %s", desc.dir, msg);
      endif
      [status, msg] = rm_rf (getarchdir (desc));
      if (status != 1)
        error ("couldn't delete directory %s: %s", getarchdir (desc), msg);
      endif
      if (dirempty (desc.archprefix))
        rm_rf (desc.archprefix);
      endif
    else
      warning ("directory %s previously lost", desc.dir);
    endif
  endfor

  ## Write a new ~/.octave_packages.
  if (global_install)
    if (length (remaining_packages) == 0)
      unlink (global_list);
    else
      global_packages = save_order (remaining_packages);
      save (global_list, "global_packages");
    endif
  else
    if (length (remaining_packages) == 0)
      unlink (local_list);
    else
      local_packages = save_order (remaining_packages);
      save (local_list, "local_packages");
    endif
  endif

endfunction