(*
    Copyright 2016-2023 Anton Krotov

    This file is part of fb2read.

    fb2read 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.

    fb2read 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 fb2read. If not, see <http://www.gnu.org/licenses/>.
*)

MODULE FB2READ;

IMPORT

    DOM, SU := SysUtils, S := Strings, W := Window, Settings, OpenDlg,
    G := Graph, SelEnc, Ini, File, box_lib, Font, SearchForm, Toolbar;


CONST

  CLOSE            =  1;
  BACK             = 16;
  FORWARD          = 17;
  CONTENTS         = 18;
  DESCR            = 19;
  SETTINGS         = 20;
  SEARCH           = 21;

  KEY_DOWN         = 80;
  KEY_UP           = 72;
  KEY_PG_DOWN      = 81;
  KEY_PG_UP        = 73;
  KEY_HOME         = 71;
  KEY_END          = 79;
  KEY_F2           = 60;
  KEY_F3           = 61;
  KEY_F4           = 62;
  KEY_F10          = 68;

  TOOLBAR_LEFT     = 5;
  TOOLBAR_TOP      = 6;
  BUTTON_HEIGHT    = 24;

  CANVAS_LEFT      = 1;
  CANVAS_TOP       = 2 * TOOLBAR_TOP + Toolbar.BtnSize;

  WINDOW_BEVEL     = 4;

  SCROLLBAR_WIDTH  = 20;
  STATUSBAR_HEIGHT = 18;

VAR

  Window     : W.tWindow;
  toolbar    : Toolbar.tToolbar;
  SkinHeight : INTEGER;
  Open       : OpenDlg.Dialog;
  FileName   : S.STRING;
  sb         : box_lib.scrollbar;


PROCEDURE ToolbarEnable;
BEGIN
	Toolbar.enable(toolbar, BACK,     DOM.BackEnabled());
	Toolbar.enable(toolbar, FORWARD,  DOM.FrwEnabled());
	Toolbar.enable(toolbar, CONTENTS, DOM.ContentsEnabled());
	Toolbar.enable(toolbar, DESCR,    DOM.DescrEnabled());
END ToolbarEnable;


PROCEDURE ToolBar;
BEGIN
	sb := box_lib.kolibri_scrollbar(sb, (G.Buffer.Width + CANVAS_LEFT) * 65536 + SCROLLBAR_WIDTH + 1,
		CANVAS_TOP * 65536 + G.Buffer.Height, SCROLLBAR_WIDTH, sb.max_area, sb.cur_area, sb.position, SU.lightColor, SU.btnColor, 0, 0);
	box_lib.scrollbar_v_draw(sb);
	ToolbarEnable;
	Toolbar.draw(toolbar);
END ToolBar;


PROCEDURE Resize;
VAR Width, Height: INTEGER;
BEGIN
  SU.GetWindowPos(Window.left, Window.top);
  SU.GetWindowSize(Width, Height);
  IF (Window.width # Width) OR (Window.height # Height) OR (SkinHeight # SU.SkinHeight()) THEN
    SU.MinMax(Width,  640, 65535);
    SU.MinMax(Height, 400, 65535);
    Window.dWidth  := Width - Window.width;
    Window.dHeight := Height - Window.height;
    Window.width   := Width;
    Window.height  := Height;
    SU.SetWindowSize(Width, Height);
    DOM.Resize(G.Buffer.Width + Window.dWidth, G.Buffer.Height + Window.dHeight + (SkinHeight - SU.SkinHeight()));
    SkinHeight := SU.SkinHeight()
  END
END Resize;


PROCEDURE DrawStatus;
BEGIN
  SU.DrawRect(0, Window.height - SkinHeight - WINDOW_BEVEL - STATUSBAR_HEIGHT + 1, Window.width - 2 * WINDOW_BEVEL - 1, STATUSBAR_HEIGHT, SU.winColor);
  IF DOM.urlstr # "" THEN
    SU.OutText(CANVAS_LEFT, Window.height - SkinHeight - WINDOW_BEVEL - STATUSBAR_HEIGHT + 2, DOM.urlstr,
      MIN(LENGTH(DOM.urlstr), (Window.width - 2 * WINDOW_BEVEL - 1 - CANVAS_LEFT * 2) DIV 8), SU.textColor)
  ELSIF DOM.found() THEN
    SU.OutText(CANVAS_LEFT,  Window.height - SkinHeight - WINDOW_BEVEL - STATUSBAR_HEIGHT + 2,
                "F2 - first | F3 - next | F4 - prev. | F10 - exit", 48, SU.textColor)
  END
END DrawStatus;


PROCEDURE DrawWindow;
BEGIN
  SU.GetSystemColors;
  SU.WindowRedrawStatus(1);
  IF Window.created THEN
    Resize
  ELSE
    Window.created := TRUE
  END;
  SU.DefineAndDrawWindow(Window.left, Window.top, Window.width, Window.height,
        SU.winColor, LSL(ORD({0, 1, 2}), 4) + 4 - ORD(DOM.loaded), Window.caption);
  SU.DrawRect(0, 0, Window.width - 2 * WINDOW_BEVEL - 1, CANVAS_TOP, SU.winColor);
  SU.DrawRect(0, Window.height - SkinHeight - WINDOW_BEVEL - STATUSBAR_HEIGHT + 1, Window.width - 2 * WINDOW_BEVEL - 1, STATUSBAR_HEIGHT, SU.winColor);
  SU.DrawRect(0, 0, CANVAS_LEFT, Window.height - SkinHeight - WINDOW_BEVEL, SU.winColor);
  SU.DrawRect(Window.width - 2 * WINDOW_BEVEL - CANVAS_LEFT - 1 - SCROLLBAR_WIDTH - 2, 0, CANVAS_LEFT + SCROLLBAR_WIDTH + 2, Window.height - SkinHeight - WINDOW_BEVEL, SU.winColor);
  IF DOM.loaded THEN
    ToolBar;
    DOM.Draw;
    DrawStatus
  END;
  SU.WindowRedrawStatus(2)
END DrawWindow;


PROCEDURE ConvMousePos(VAR X, Y: INTEGER);
BEGIN
  X := X - Window.left - WINDOW_BEVEL - 1;
  Y := Y - Window.top - SkinHeight
END ConvMousePos;


PROCEDURE DrawToolbar;
BEGIN
	ToolbarEnable;
	Toolbar.drawIcons(toolbar)
END DrawToolbar;


PROCEDURE ButtonClick;
BEGIN
  CASE SU.GetButtonCode() OF
  |0        :
  |CLOSE    : SearchForm.close(FALSE);
              Settings.Close;
              DOM.Close
  |BACK     : DOM.Back
  |FORWARD  : DOM.Forward
  |CONTENTS : DOM.Contents
  |DESCR    : DOM.Descr
  |SEARCH   : DOM.OpenSearch
  |SETTINGS : Settings.Open
  END;
  DOM.Draw;
  DrawStatus
END ButtonClick;


PROCEDURE KeyDown;
VAR
	key: INTEGER;
	shift, ctrl: BOOLEAN;
BEGIN
	SU.getKBState(shift, ctrl);
	key := SU.GetKey() DIV 65536;
	CASE key OF
	|KEY_DOWN    : DOM.Scroll(1)
	|KEY_UP      : DOM.Scroll(-1)
	|KEY_PG_DOWN : DOM.PageDown
	|KEY_PG_UP   : DOM.PageUp
	|KEY_HOME    : DOM.Home
	|KEY_END     : DOM.End
	|KEY_F2      : DOM.Find(0)
	|KEY_F3      : DOM.Find(1)
	|KEY_F4      : DOM.Find(-1)
	|KEY_F10     : DOM.CloseSearch
	|33          : IF ctrl THEN DOM.OpenSearch END (* ctrl-F *)
	ELSE
	END;
	DOM.Draw;
	DrawStatus
END KeyDown;


PROCEDURE CanvasIsClicked(X, Y: INTEGER): BOOLEAN;
  RETURN
    (CANVAS_LEFT <= X) & (X < CANVAS_LEFT + G.Buffer.Width)  &
    (CANVAS_TOP  <= Y) & (Y < CANVAS_TOP  + G.Buffer.Height)
END CanvasIsClicked;


PROCEDURE MouseEvent;
VAR
  mouse_status : SET;
  X, Y         : INTEGER;
  scroll       : INTEGER;
BEGIN
  SU.MousePos(X, Y);
  mouse_status := SU.MouseStatus();
  scroll := SU.MouseVScroll();
  IF SU.L_BUTTON IN mouse_status THEN
    ConvMousePos(X, Y);
    IF CanvasIsClicked(X, Y) THEN
      X := X - CANVAS_LEFT;
      Y := Y - CANVAS_TOP;
      DOM.Click(X, Y, TRUE)
    END
  ELSIF scroll # 0 THEN
    DOM.Scroll(scroll*2);
    DOM.Draw
  ELSE
    ConvMousePos(X, Y);
    IF CanvasIsClicked(X, Y) THEN
      X := X - CANVAS_LEFT;
      Y := Y - CANVAS_TOP;
      DOM.Click(X, Y, FALSE)
    END
  END
END MouseEvent;


PROCEDURE Empty;
END Empty;


PROCEDURE OpenFile;
BEGIN
  Open := OpenDlg.Create(Empty, 0, Ini.Default, Ini.Files);
  OpenDlg.Show(Open, 500, 400);
  WHILE Open.status = 2 DO
    SU.Pause(30)
  END;
  IF Open.status = 0 THEN
    SU.Halt
  END;
  COPY(Open.FilePath, FileName);
  OpenDlg.Destroy(Open)
END OpenFile;


PROCEDURE IsFB2(FileName: S.STRING): BOOLEAN;
VAR temp: S.STRING;
BEGIN
  temp := FileName;
  S.Reverse(temp);
  temp[4] := 0X;
  S.UCase(temp)
  RETURN temp = "2BF."
END IsFB2;


PROCEDURE main(title: ARRAY OF CHAR);
VAR WinW, X1, Y1, X2, Y2, scr_pos: INTEGER; Win2: W.tWindow; resize: BOOLEAN; FilePath: S.STRING; defpath: BOOLEAN;
BEGIN
  SkinHeight := SU.SkinHeight();
  sb := box_lib.kolibri_new_scrollbar(10 * 65536 + 200, 10 * 65536 + 30, 25, 15, 10, 0, 0, 0, 0, 0);
  DOM.SetScrollBar(sb);
  defpath := TRUE;
  SU.GetParam(FileName);
  IF FileName = "" THEN
    OpenFile
  END;

  IF FileName[0] = "!" THEN
    FileName[0] := "/";
    defpath := FALSE
  END;

  IF defpath THEN
    FilePath := FileName;
    S.GetPath(FilePath);
    Ini.SetDefaultPath(FilePath);
    DOM.SetColors;
    DOM.Set_b_pict(Ini.b_pict);
    Ini.Save(DOM.Settings.Colors, DOM.Settings.b_pict)
  END;

  IF ~IsFB2(FileName) THEN
    SelEnc.Show(FileName)
  END;

  SU.SetEventsMask({0, 1, 2, 5, 31});
  SU.GetScreenArea(X1, Y1, X2, Y2);
  WinW := (X2 - X1) DIV 2;
  W.init(Window, WinW DIV 2, Y1, WinW, Y2 - Y1, title);
  Settings.Default;
  DOM.GetWinSize(FileName, Window.width, Window.height);

  Win2 := Window;
  resize := FALSE;
  IF Win2.width > X2 - X1 THEN
    Win2.width := X2 - X1;
    resize := TRUE
  END;

  IF Win2.height > Y2 - Y1 THEN
    Win2.height := Y2 - Y1;
    resize := TRUE
  END;

  DOM.Init(CANVAS_LEFT, CANVAS_TOP,
        Window.width - 2 * CANVAS_LEFT - 2 * WINDOW_BEVEL - 1 - SCROLLBAR_WIDTH - 2,
        Window.height - SkinHeight - CANVAS_TOP - WINDOW_BEVEL - STATUSBAR_HEIGHT + 1);
  DOM.SetColors;
  DOM.Set_b_pict(Ini.b_pict);
  Window := Win2;
  G.InitSize(Window.width - 2 * CANVAS_LEFT - 2 * WINDOW_BEVEL - 1 - SCROLLBAR_WIDTH, Window.height - SkinHeight - CANVAS_TOP - WINDOW_BEVEL + 1 - STATUSBAR_HEIGHT);
  S.Append(Window.caption, " - ");
  S.Append(Window.caption, FileName);

	Toolbar.create(toolbar, TOOLBAR_LEFT, TOOLBAR_TOP);
    Toolbar.add(toolbar, BACK,      30, "");
    Toolbar.add(toolbar, FORWARD,   31, "");
    Toolbar.delimiter(toolbar);
    Toolbar.add(toolbar, CONTENTS,   3, "");
    Toolbar.delimiter(toolbar);
    Toolbar.add(toolbar, SEARCH,    49, "");
    Toolbar.delimiter(toolbar);
    Toolbar.add(toolbar, DESCR,     66, "");
    Toolbar.delimiter(toolbar);
    Toolbar.add(toolbar, SETTINGS,  60, "");

  DOM.Open(FileName, DrawWindow, DrawStatus, DrawToolbar);
  IF resize THEN
    DOM.Resize(Window.width - 2 * CANVAS_LEFT - 2 * WINDOW_BEVEL - 1 - SCROLLBAR_WIDTH, Window.height - SkinHeight - CANVAS_TOP - WINDOW_BEVEL + 1 - STATUSBAR_HEIGHT)
  END;

  DrawWindow;
  scr_pos := sb.position;
  WHILE TRUE DO
    CASE SU.WaitForEvent() OF
    |1 : DrawWindow
    |2 : KeyDown
    |3 : ButtonClick
    |6 : box_lib.scrollbar_v_mouse(sb);
         IF sb.position # scr_pos THEN
           DOM.ScrollBar;
           DOM.Draw;
           scr_pos := sb.position;
         END;
         MouseEvent
    END
  END
END main;


BEGIN
  main("FB2 Reader v0.97a")
END FB2READ.