//
//	aegis - project change supervisor
//	Copyright (C) 1999, 2001-2008 Peter Miller
//	Copyright (C) 2007, 2008 Walter Franzini
//
//	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/error.h> // for assert
#include <common/symtab.h>
#include <common/symtab_iter.h>
#include <common/symtab/template.h>
#include <common/trace.h>

#include <libaegis/change/branch.h>
#include <libaegis/change/file.h>
#include <libaegis/project.h>
#include <libaegis/sub.h>


static void
fimprove(fstate_ty *fstate_data, string_ty *, change::pointer cp)
{
    trace(("fimprove(%08lX, , %s)\n{\n", (long)fstate_data,
           change_version_get(cp)->str_text));

    if (!fstate_data->src)
    {
	fstate_data->src = (fstate_src_list_ty *)fstate_src_list_type.alloc();
    }

    //
    // Migrate file state information.
    //
    symtab<fstate_src_ty> create_half;
    symtab<fstate_src_ty> remove_half;
    for (size_t j = 0; j < fstate_data->src->length; ++j)
    {
	fstate_src_ty   *src;

	src = fstate_data->src->list[j];

	//
	// Fix an ugly inconsistency in the file action.
	//
	if (src->deleted_by)
	    src->action = file_action_remove;

	//
	// Historical 4.9 -> 4.10 transition.
	//
	// This is here to cope with cases where the users upgrade with
	// changes between 'being reviewed' and 'being integrated' states.
	//
	// This code must agree with the corresponding code in
	// libaegis/project.c
	//
	switch (src->action)
	{
	case file_action_transparent:
            break;

	case file_action_remove:
            //
            // There was once a bug in aeclone which caused the
            // edit_origin field to be omitted for removed files.  This,
            // in turn, led to project file entries with no edit_origin
            // field, which hauses assert failues and segfaults all over
            // the place.
            //
            if (!src->edit_origin && !src->edit_number_origin)
            {
                //
                // The problem is , what the heck to we replace it with?
                // Probably not important, since it will never be passed
                // to the history_get_command.
                //
                src->edit_origin =
                    (history_version_ty *)history_version_type.alloc();
                src->edit_origin->errpos = str_copy(src->errpos);
                src->edit_origin->revision = str_from_c("0.0");
                src->edit_origin->encoding = history_version_encoding_none;
            }
	    break;

	case file_action_create:
	case file_action_modify:
	case file_action_insulate:
#ifndef DEBUG
	default:
#endif
	    if (src->about_to_be_created_by || src->about_to_be_copied_by)
		src->action = file_action_transparent;
	    break;
	}

	//
	// Historical 2.3 -> 3.0 transition.
	//
	// This covers a transitional glitch in the edit number
	// semantics.  Very few installed sites will ever
	// need this.
	//
	if (src->edit_number && !src->edit_number_origin)
	    src->edit_number_origin = str_copy(src->edit_number);

	//
	// Historical 3.24 to 3.25 transition.
	//
	// This was when history file contents encoding was added,
	// so that we could cope with binary files transparently,
	// even for ascii-only history tools.
	//
	if (src->edit_number)
	{
	    src->edit = (history_version_ty *)history_version_type.alloc();
	    src->edit->errpos = str_copy(src->errpos);
	    src->edit->revision = src->edit_number;
	    src->edit->encoding = history_version_encoding_none;
	    src->edit_number = 0;
	}
	if (src->edit_number_origin)
	{
	    src->edit_origin =
                (history_version_ty *)history_version_type.alloc();
	    src->edit_origin->errpos = str_copy(src->errpos);
	    src->edit_origin->revision = src->edit_number_origin;
	    src->edit_origin->encoding = history_version_encoding_none;
	    src->edit_number_origin = 0;
	}
	if (src->edit_number_origin_new)
	{
	    src->edit_origin_new =
                (history_version_ty *)history_version_type.alloc();
	    src->edit_origin_new->errpos = str_copy(src->errpos);
	    src->edit_origin_new->revision = src->edit_number_origin_new;
	    src->edit_origin_new->encoding = history_version_encoding_none;
	    src->edit_number_origin_new = 0;
	}

	//
	// Make sure things are where they are meant to be.
	//
	if (src->edit && !src->edit->revision)
	{
	    sub_context_ty  *scp;

	    assert(src->edit->errpos);
	    scp = sub_context_new();
	    sub_var_set_string(scp, "File_Name", src->edit->errpos);
	    sub_var_set_charstar(scp, "FieLD_Name", "edit.revision");
	    change_fatal
	    (
		cp,
		scp,
		i18n("$filename: contains no \"$field_name\" field")
	    );
	    // NOTREACHED
	    sub_context_delete(scp);
	}
	if (src->edit_origin && !src->edit_origin->revision)
	{
	    sub_context_ty  *scp;

	    assert(src->edit_origin->errpos);
	    scp = sub_context_new();
	    sub_var_set_string(scp, "File_Name", src->edit_origin->errpos);
	    sub_var_set_charstar(scp, "FieLD_Name", "edit_origin.revision");
	    change_fatal
	    (
		cp,
		scp,
		i18n("$filename: contains no \"$field_name\" field")
	    );
	    // NOTREACHED
	    sub_context_delete(scp);
	}
	if (src->edit_origin_new && !src->edit_origin_new->revision)
	{
	    sub_context_ty  *scp;

	    assert(src->edit_origin_new->errpos);
	    scp = sub_context_new();
	    sub_var_set_string(scp, "File_Name", src->edit_origin_new->errpos);
	    sub_var_set_charstar(scp, "FieLD_Name", "edit_origin_new.revision");
	    change_fatal
	    (
		cp,
		scp,
		i18n("$filename: contains no \"$field_name\" field")
	    );
	    // NOTREACHED
	    sub_context_delete(scp);
	}

        //
        // Adjust the move field in order to cope with a bug in the
        // aeipass code.  We need another pass to fix the removed
        // files.
        //
        switch (src->action)
        {
        case file_action_remove:
            if (src->move && change_was_a_branch(cp))
            {
                trace(("remember %s;\n", src->file_name->str_text));
                remove_half.assign (nstring(src->file_name), src);
            }
            break;

        case file_action_create:
            if (src->move && change_was_a_branch(cp))
                create_half.assign(nstring(src->file_name), src);
            break;

        case file_action_insulate:
        case file_action_modify:
        case file_action_transparent:
#ifndef DEBUG
        default:
#endif
            if (src->move)
            {
                trace(("reset move;\n"));
                str_free(src->move);
                src->move = 0;
            }
            break;
        }
    }

    //
    // Adjust the move field, we now fix the deleted files.
    //
    if (remove_half.size() > 0)
    {
	assert(change_was_a_branch(cp));
        nstring_list candidate;

        remove_half.keys(candidate);
        trace(("candidate.size() = %ld;\n", (long)candidate.size()));

        for (size_t i = 0; i < remove_half.size(); ++i)
        {
            trace_nstring(candidate[i]);
            fstate_src_ty *src2 = remove_half.query(candidate[i]);
	    //
	    // Skip over if src2 is NULL, it means the file has already
	    // been removed from the list.
	    //
            if (!src2)
		continue;
            assert(src2->move);

            trace_string(src2->move->str_text);

            fstate_src_ty *src3 = remove_half.query(src2->move);
            trace_pointer(src3);

            //
            // Skip over is src3 is NULL, it means the file has already
	    // been removed from the list.
            //
            if (!src3)
                continue;
	    assert(src3->move);

            //
            // Skip over if src3->move is the create half of a rename.
            //
            if (create_half.query(src3->move))
                continue;

	    //
	    // If the deletion comes from the same branch we need to go
	    // down one step to retrieve the right value.
	    // Otherwise we compare the integration_timestamp of the changes.
	    //
            project_ty *pp = cp->pp->bind_branch(cp);
            assert(pp);
            trace(("pp->version = \"%s\";\n",
                   project_version_get(pp)->str_text));
	    if (src2->deleted_by == src3->deleted_by)
	    {
                change::pointer cp2 = change_alloc(pp, src2->deleted_by);
                change_bind_existing(cp2);

		change_fstate_get(cp2);
		assert(cp2->fstate_stp);

		fstate_src_ty *src2_tmp =
		    (fstate_src_ty*)cp2->fstate_stp->query(src2->file_name);
		fstate_src_ty *src3_tmp =
		    (fstate_src_ty*)cp2->fstate_stp->query(src3->file_name);

                assert
                (
                    (src3_tmp->move && !src2_tmp->move)
                ||
                    (src2_tmp->move && !src3_tmp->move)
                );

                if (!src2_tmp->move)
                {
                    str_free(src2->move);
                    src2->move = 0;
                    remove_half.remove(nstring(src2->file_name));
                }
                else
                {
                    assert(str_equal(src2->move, src2_tmp->move));
                }

                if (!src3_tmp->move)
                {
                    str_free(src3->move);
                    src3->move = 0;
                    remove_half.remove(nstring(src3->file_name));
                }
                else
                {
                    assert(str_equal(src3->move, src3_tmp->move));
                }
	    }
            else
            {
                //
                // The files are modified by two *different* changes.
                // Since the only possibile scenario is to have a
                // rename followed by a delete (and not the other
                // way), the most recent change is a deletion and
                // it cannot have the move field set.
                //
                time_t completion_timestamp2 =
                    pp->change_completion_timestamp(src2->deleted_by);
                time_t completion_timestamp3 =
                    pp->change_completion_timestamp(src3->deleted_by);
                assert(completion_timestamp2 != completion_timestamp3);
                if (completion_timestamp2 < completion_timestamp3)
                {
                    trace(("reset move;\n"));
                    str_free(src3->move);
                    src3->move = 0;
                    remove_half.remove(nstring(src3->file_name));
                }
                else
                {
                    trace(("reset move;\n"));
                    str_free(src2->move);
                    src2->move = 0;
                    remove_half.remove(candidate[i]);
                }
            }
            // project_free(pp);
        }
    }

    trace(("return;\n"));
    trace(("}\n"));
}


fstate_ty *
change_fstate_get(change::pointer cp)
{
    string_ty	    *fn;
    size_t	    j;

    //
    // make sure the change state has been read in,
    // in case its src field needed to be converted.
    // (also to ensure lock_sync has been called for both)
    //
    trace(("change_fstate_get(cp = %08lX)\n{\n", (long)cp));
    cp->cstate_get();

    if (!cp->fstate_data)
    {
	fn = change_fstate_filename_get(cp);
	change_become(cp);
	cp->fstate_data = fstate_read_file(fn);
	change_become_undo(cp);
	fimprove(cp->fstate_data, fn, cp);
    }
    if (!cp->fstate_data->src)
    {
	cp->fstate_data->src =
            (fstate_src_list_ty *)fstate_src_list_type.alloc();
    }

    //
    // Create a couple of O(1) indexes.
    // This speeds up just about everything.
    //
    if (!cp->fstate_stp)
    {
	cp->fstate_stp = symtab_alloc(cp->fstate_data->src->length);
	cp->fstate_uuid_stp = symtab_alloc(cp->fstate_data->src->length);
	for (j = 0; j < cp->fstate_data->src->length; ++j)
	{
	    fstate_src_ty *p = cp->fstate_data->src->list[j];
	    symtab_assign(cp->fstate_stp, p->file_name, p);
	    if (p->uuid && (!p->move || p->action != file_action_remove))
		symtab_assign(cp->fstate_uuid_stp, p->uuid, p);
	}
    }
    trace(("return %08lX;\n", (long)cp->fstate_data));
    trace(("}\n"));
    return cp->fstate_data;
}