//
//      aegis - project change supervisor
//      Copyright (C) 1999, 2001-2008, 2012, 2014 Peter Miller
//
//      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 3 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, see
//      <http://www.gnu.org/licenses/>.
//

#include <common/ac/assert.h>

#include <common/trace.h>
#include <libaegis/change.h>
#include <libaegis/change/env_set.h>
#include <libaegis/os.h>
#include <libaegis/project.h>
#include <libaegis/sub.h>


string_ty *
change_run_history_query_command(change::pointer cp, fstate_src_ty *src)
{
    sub_context_ty  *scp;
    string_ty       *hp;
    pconf_ty        *pconf_data;
    string_ty       *the_command;
    string_ty       *result;
    string_ty       *hfn;

    //
    // Ask the history file what its edit number is.  We use this
    // method because the string returned is essentially random,
    // between different history programs.  Only ever executed in
    // the "being integrated" state.  Current directory will be
    // set to the base of the history tree.  All of the
    // substitutions described in aesub(5) are available.  In
    // addition
    //
    // ${History}
    //  absolute path of history file
    //
    trace(("change_run_history_query_command(cp = %p, "
        "src->file_name = \"%s\")\n{\n", cp.get(), src->file_name->str_text));
    assert(cp->valid());
    pconf_data = change_pconf_get(cp, 1);
    hfn = project_history_filename_get(cp->project_get(), src);
    scp = sub_context_new();
    sub_var_set_string(scp, "History", hfn);
    str_free(hfn);
    the_command = pconf_data->history_query_command;
    if (!the_command)
    {
        sub_context_ty  *scp2;

        assert(pconf_data->errpos);
        scp2 = sub_context_new();
        sub_var_set_string(scp2, "File_Name", pconf_data->errpos);
        sub_var_set_charstar(scp2, "FieLD_Name", "history_query_command");
        change_fatal
        (
            cp,
            scp2,
            i18n("$filename: contains no \"$field_name\" field")
        );
        // NOTREACHED
        sub_context_delete(scp2);
    }
    the_command = substitute(scp, cp, the_command);
    sub_context_delete(scp);

    change_env_set(cp, 0);
    hp = cp->project_get()->history_path_get();
    project_become(cp->project_get());
    result = os_execute_slurp(the_command, OS_EXEC_FLAG_NO_INPUT, hp);
    project_become_undo(cp->project_get());
    str_free(the_command);
    if (!result->str_length)
        fatal_intl(0, i18n("history_query_command return empty"));
    trace(("return \"%s\";\n", result->str_text));
    trace(("}\n"));
    return result;
}


// vim: set ts=8 sw=4 et :