(*
    Copyright 2021, 2022 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 <http://www.gnu.org/licenses/>.
*)

MODULE Clipboard;

IMPORT SYSTEM, KOSAPI, E := Encodings, Lines, K := KolibriOS;

CONST
    TTEXT = 0;
    lenEOL* = 2;

TYPE
    tBuffer* = POINTER TO RECORD
        dataPtr*: INTEGER;
        pos: INTEGER
    END;


PROCEDURE free (ptr: INTEGER);
BEGIN
    ptr := KOSAPI.free(ptr)
END free;


PROCEDURE bufSize* (buffer: tBuffer): INTEGER;
    RETURN buffer.pos - buffer.dataPtr
END bufSize;


PROCEDURE put* (buffer: tBuffer);
VAR
    a, cnt, size: INTEGER;
    ptr, pchar: INTEGER;
    wch: WCHAR;
BEGIN
    cnt := bufSize(buffer) DIV SYSTEM.SIZE(WCHAR);
    size := cnt + 12;
    a := KOSAPI.malloc(size);
    ASSERT(a # 0);
    SYSTEM.PUT32(a + 4, TTEXT);
    SYSTEM.PUT32(a + 8, 1);
    pchar := a + 12;
    ptr := buffer.dataPtr;
    WHILE cnt > 0 DO
        SYSTEM.GET(ptr, wch);
        IF wch = Lines.TAB1 THEN
        	DEC(size)
        ELSIF wch = Lines.NUL THEN
            SYSTEM.PUT(pchar, 0X);
            INC(pchar)
        ELSE
            SYSTEM.PUT(pchar, CHR(E.UNI[ORD(wch), E.CP866] MOD 256));
            INC(pchar)
        END;
        INC(ptr, 2);
        DEC(cnt)
    END;
    SYSTEM.PUT32(a, size);
    K.CBDelSlot;
    K.CBWrite(size, a)
END put;


PROCEDURE create* (bufSize: INTEGER): tBuffer;
VAR
    res: tBuffer;
BEGIN
    NEW(res);
    res.dataPtr := KOSAPI.malloc(bufSize*SYSTEM.SIZE(WCHAR) + 4096);
    ASSERT(res.dataPtr # 0);
    res.pos := res.dataPtr
    RETURN res
END create;


PROCEDURE destroy* (VAR buffer: tBuffer);
BEGIN
    IF buffer # NIL THEN
        IF buffer.dataPtr # 0 THEN
            free(buffer.dataPtr)
        END;
        DISPOSE(buffer)
    END
END destroy;


PROCEDURE append* (buffer: tBuffer; line: Lines.tLine; first, last: INTEGER);
VAR
    strSize: INTEGER;
BEGIN
    strSize := (last - first + 1)*SYSTEM.SIZE(WCHAR);
    IF strSize > 0 THEN
        SYSTEM.MOVE(Lines.getPChar(line, first), buffer.pos, strSize);
        INC(buffer.pos, strSize)
    END
END append;


PROCEDURE appends* (buffer: tBuffer; s: ARRAY OF WCHAR; first, last: INTEGER);
VAR
    strSize: INTEGER;
BEGIN
    strSize := (last - first + 1)*SYSTEM.SIZE(WCHAR);
    IF strSize > 0 THEN
        SYSTEM.MOVE(SYSTEM.ADR(s[first]), buffer.pos, strSize);
        INC(buffer.pos, strSize)
    END
END appends;


PROCEDURE eol* (buffer: tBuffer);
BEGIN
    appends(buffer, 0DX + 0AX, 0, 1)
END eol;


PROCEDURE eot* (buffer: tBuffer);
END eot;


PROCEDURE available* (): BOOLEAN;
VAR
    ptr: INTEGER;
    n, size, typ, x: INTEGER;
    res: BOOLEAN;
BEGIN
    res := FALSE;
    n := K.CBCount();
    IF n > 0 THEN
        ptr := K.CBRead(n - 1);
        SYSTEM.GET32(ptr, size);
        SYSTEM.GET32(ptr + 4, typ);
        SYSTEM.GET(ptr + 8, x);
        res := (typ = TTEXT) & (x = 1);
        free(ptr)
    END
    RETURN res
END available;


PROCEDURE get* (VAR cnt: INTEGER): INTEGER;
VAR
    ptr: INTEGER;
BEGIN
    ptr := 0;
    cnt := 0;
    IF available() THEN
        ptr := K.CBRead(K.CBCount() - 1);
        SYSTEM.GET32(ptr, cnt);
        DEC(cnt, 12);
        INC(ptr, 12)
    END
    RETURN ptr
END get;


END Clipboard.