Subversion Repositories Kolibri OS

(*

    Copyright 2021 Anton Krotov

    This file is part of CEdit.

    CEdit 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.

    CEdit 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 CEdit. If not, see .

*)

MODULE ChangeLog;

IMPORT List, Lines, (*API,*) SYSTEM;

TYPE

    tIntItem = POINTER TO RECORD (List.tItem)

        adr, val: INTEGER

    END;

    tBoolItem = POINTER TO RECORD (List.tItem)

        adr: INTEGER; val: BOOLEAN; save: BOOLEAN

    END;

(*

    tUntypedPtr = POINTER TO RECORD (List.tItem)

        p: INTEGER

    END;

    tTypedPtr = POINTER TO RECORD (List.tItem)

        p: List.tItem

    END;

*)

    tGuard* = POINTER TO RECORD (List.tItem)

        saved*: BOOLEAN

    END;

    tLog* = POINTER TO RECORD

        Log*: List.tList;

        guard: tGuard;

        isLast: BOOLEAN

    END;

VAR

    CL*: tLog;

PROCEDURE isLastGuard* (guard: tGuard): BOOLEAN;

VAR

    item: List.tItem;

    res: BOOLEAN;

BEGIN

    IF guard # NIL THEN

        item := CL.Log.last;

        WHILE ~(item IS tGuard) DO

            item := item.prev

        END;

        res := guard = item

    ELSE

        res := TRUE

    END

    RETURN res

END isLastGuard;

PROCEDURE isFirstGuard* (guard: tGuard): BOOLEAN;

VAR

    item: List.tItem;

BEGIN

    ASSERT(guard # NIL);

    item := CL.Log.first;

    WHILE ~(item IS tGuard) DO

        item := item.next

    END

    RETURN guard = item

END isFirstGuard;

PROCEDURE setGuard* (_guard: tGuard);

BEGIN

    CL.guard := _guard;

    CL.isLast := isLastGuard(_guard)

END setGuard;

PROCEDURE redo* (item: List.tItem);

BEGIN

    IF item IS tIntItem THEN

        SYSTEM.PUT(item(tIntItem).adr, item(tIntItem).val)

    ELSIF item IS tBoolItem THEN

        SYSTEM.PUT(item(tBoolItem).adr, item(tBoolItem).val)

    END

END redo;

PROCEDURE clear (guard: tGuard);

VAR

    item: List.tItem;

    (*res: INTEGER;*)

BEGIN

    CL.isLast := TRUE;

    REPEAT

        item := List.pop(CL.Log);

        IF item # guard THEN

        (*

            IF item IS tUntypedPtr THEN

                res := API._DISPOSE(item(tUntypedPtr).p)

            ELSIF item IS tTypedPtr THEN

                DISPOSE(item(tTypedPtr).p)

            END;*)

            DISPOSE(item)

        END

    UNTIL item = guard;

    List.append(CL.Log, item)

END clear;

PROCEDURE save* (guard: tGuard);

VAR

    item: List.tItem;

BEGIN

    item := CL.Log.first;

    WHILE item # NIL DO

        IF item IS tGuard THEN

            item(tGuard).saved := FALSE

        END;

        item := item.next

    END;

    guard.saved := TRUE

END save;

PROCEDURE changeWord (adrV, adrX: INTEGER);

VAR

    item: tIntItem;

BEGIN

    NEW(item);

    item.adr := adrV;

    SYSTEM.GET(adrX, item.val);

    IF ~CL.isLast THEN

        clear(CL.guard)

    END;

    List.append(CL.Log, item)

END changeWord;

PROCEDURE changeBool (VAR v: BOOLEAN; x: BOOLEAN);

VAR

    item: tBoolItem;

BEGIN

    NEW(item);

    item.adr := SYSTEM.ADR(v);

    item.val := x;

    item.save := FALSE;

    IF ~CL.isLast THEN

        clear(CL.guard)

    END;

    List.append(CL.Log, item)

END changeBool;

PROCEDURE delSaved*;

VAR

    boolItem: tBoolItem;

    cur: List.tItem;

    del: BOOLEAN;

BEGIN

    cur := CL.guard.next;

    WHILE cur # NIL DO

        IF cur IS tBoolItem THEN

            boolItem := cur(tBoolItem);

            del := boolItem.save

        ELSE

            del := FALSE

        END;

        cur := cur.next;

        IF del THEN

            List.delete(CL.Log, boolItem);

            DISPOSE(boolItem)

        END

    END

END delSaved;

PROCEDURE delCurSaved*;

VAR

    boolItem: tBoolItem;

    cur: List.tItem;

    del: BOOLEAN;

BEGIN

    cur := CL.guard.prev;

    WHILE (cur # NIL) & ~(cur IS tGuard) DO

        IF cur IS tBoolItem THEN

            boolItem := cur(tBoolItem);

            del := boolItem.save

        ELSE

            del := FALSE

        END;

        cur := cur.prev;

        IF del THEN

            SYSTEM.PUT(boolItem.adr, ~boolItem.val);

            List.delete(CL.Log, boolItem);

            DISPOSE(boolItem)

        END

    END

END delCurSaved;

PROCEDURE changeBool2 (VAR v: BOOLEAN; x: BOOLEAN);

VAR

    item, boolItem: tBoolItem;

    cur: List.tItem;

    del: BOOLEAN;

BEGIN

    NEW(item);

    item.adr := SYSTEM.ADR(v);

    item.val := x;

    item.save := TRUE;

    cur := CL.guard.prev;

    WHILE cur # NIL DO

        IF cur IS tBoolItem THEN

            boolItem := cur(tBoolItem);

            del := boolItem.save & (boolItem.adr = SYSTEM.ADR(v)) & (boolItem.val = x)

        ELSE

            del := FALSE

        END;

        cur := cur.prev;

        IF del THEN

            List.delete(CL.Log, boolItem);

            DISPOSE(boolItem)

        END

    END;

    List.insert(CL.Log, CL.guard.prev, item)

END changeBool2;

PROCEDURE changeInt (VAR v: INTEGER; x: INTEGER);

BEGIN

    changeWord(SYSTEM.ADR(v), SYSTEM.ADR(x))

END changeInt;

PROCEDURE changePtr (VAR v: List.tItem; x: List.tItem);

BEGIN

    changeWord(SYSTEM.ADR(v), SYSTEM.ADR(x))

END changePtr;

(*

PROCEDURE typedPtr (p: List.tItem);

VAR

    item: tTypedPtr;

BEGIN

    NEW(item);

    item.p := p;

    List.append(Log, item)

END typedPtr;

PROCEDURE untypedPtr (p: INTEGER);

VAR

    item: tUntypedPtr;

BEGIN

    NEW(item);

    item.p := p;

    List.append(Log, item)

END untypedPtr;

*)

PROCEDURE set* (_CL: tLog);

BEGIN

    CL := _CL

END set;

PROCEDURE create* (VAR maxLength: INTEGER): tLog;

VAR

    newLog: tLog;

BEGIN

    NEW(newLog);

    newLog.guard := NIL;

    newLog.isLast := TRUE;

    newLog.Log := List.create(NIL);

    CL := newLog;

    Lines.setMaxLength(maxLength)

    RETURN newLog

END create;

BEGIN

    List.init(changeInt, changePtr);

    Lines.init(changeInt, changePtr, changeBool, changeBool2(*, typedPtr, untypedPtr*))

END ChangeLog.