Form DEMO_COMMAND_RECALL_FORM
    /*
 		      © Copyright 2005 Hewlett-Packard Development Company, L.P.

  Consistent with FAR 12.211 and 12.212, Commercial Computer Software,
  Computer Software Documentation, and Technical Data for Commercial
  Items are licensed to the U.S. Government under vendor's standard
  commercial license.

   This IFDL file is designed to be translated and then simply enabled in
   order to see the effect. Just enter commands and use the up/down arrow
   keys to scroll. There is no program behind this form to execute the
   commands but you should get the idea of command recall from what you see
   on the display.

   keys: 
   	 RETURN -- simulates going back to the program but really just 
	     displays a message and scrolls to the next command line 
	     after clearing it.
	 F10 exit (ends session in this demo)
	 TAB goes to next line of command 
	 BS  goes to previous line of command
	 UP ARROW scrolls to previous command
	 DOWN ARROW scrolls to next command
*/

    Form Data 
        STYLE Character(3)
        RECALL_STYLE_TEXT Character(50)
        CRC_STYLE_TEXT Character(50)
            Value "using a circular buffer of size 12 entries.       "
        VMS_STYLE_TEXT Character(50)
            Value "using VMS-style recall of up to 12 entries.       "
        COMMAND_CHARS Character(36)
        COMMAND_LINE_1 Character(69)
        COMMAND_LINE_2 Character(80)
        Group COMMAND_LINES 
            Occurs 12
            CURRENT_LINE_NBR Integer(2)
            COMMAND_LINE_1 Character(69)
            COMMAND_LINE_2 Character(80)
            PREVIOUS_INDEX Byte Integer
            NEXT_INDEX Byte Integer
        End Group
        COMMAND_INDEX Byte Integer
        COMMAND_POINTER Byte Integer
    End Data

    Form Record MENU_SELECTION
        /* 
   This form record would be used in a RECEIVE request to get the current 
   command selection back from the form to the program. Note the use of the 
   TRANSFER ... SOURCE ... clause, this moves the current command line (the 
   one visible to the user) to the form record area.
*/
        Group CURRENT_COMMAND
            COMMAND_LINE_1 Character(69)
            Transfer CURRENT_COMMAND.COMMAND_LINE_1
                    Source COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1
            COMMAND_LINE_2 Character(80)
            Transfer CURRENT_COMMAND.COMMAND_LINE_2
                    Source COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_2
        End Group

    End Record


    Layout VT_LAYOUT
        Device
            Terminal
                Type %VT100
        End Device
        Size 24 Lines by 80 Columns

        Viewport MENU_VP
            Lines 1 Through 23
            Columns 1 Through 80
        End Viewport

        Viewport INFO_VP
            Lines 1 Through 21
            Columns 1 Through 80
        End Viewport

        Viewport SELECT_LINE_VIEW
            Lines 22 Through 23
            Columns 1 Through 80
        End Viewport

        Function SHOW_VALUES
            Is %F9
        End Function

        Function MENU_SELECT
            Is %SELECT
        End Function

        Function DO_COMMAND
            Is %CARRIAGE_RETURN
        End Function

        Function RECALL
            Is %FIND
            /* not yet implemented */
        End Function

        Function NEXT ITEM
            Is %HORIZONTAL_TAB
        End Function

        Function UP ITEM
            Is %UP
        End Function

        Function DOWN ITEM
            Is %DOWN
        End Function

        Function COMMAND_UP
            Is %UP
        End Function

        Function COMMAND_DOWN
            Is %DOWN
        End Function

        Function INIT_COMMANDS
            Is %F18
        End Function

        Function CLEAR_COMMANDS
            Is (%PF1 %F18)
        End Function

        Function DO_IT_AGAIN
            Is %F19
        End Function

        Function CLEAR_MESSAGE_AREA
            Is %F20
        End Function

        Internal Response SETUP_SCROLL_CONTROL
            Let COMMAND_LINES(1).CURRENT_LINE_NBR = 1
            Let COMMAND_LINES(1).PREVIOUS_INDEX = 12
            Let COMMAND_LINES(1).NEXT_INDEX = 2
            Let COMMAND_LINES(2).CURRENT_LINE_NBR = 2
            Let COMMAND_LINES(2).PREVIOUS_INDEX = 1
            Let COMMAND_LINES(2).NEXT_INDEX = 3
            Let COMMAND_LINES(3).CURRENT_LINE_NBR = 3
            Let COMMAND_LINES(3).PREVIOUS_INDEX = 2
            Let COMMAND_LINES(3).NEXT_INDEX = 4
            Let COMMAND_LINES(4).CURRENT_LINE_NBR = 4
            Let COMMAND_LINES(4).PREVIOUS_INDEX = 3
            Let COMMAND_LINES(4).NEXT_INDEX = 5
            Let COMMAND_LINES(5).CURRENT_LINE_NBR = 5
            Let COMMAND_LINES(5).PREVIOUS_INDEX = 4
            Let COMMAND_LINES(5).NEXT_INDEX = 6
            Let COMMAND_LINES(6).CURRENT_LINE_NBR = 6
            Let COMMAND_LINES(6).PREVIOUS_INDEX = 5
            Let COMMAND_LINES(6).NEXT_INDEX = 7
            Let COMMAND_LINES(7).CURRENT_LINE_NBR = 7
            Let COMMAND_LINES(7).PREVIOUS_INDEX = 6
            Let COMMAND_LINES(7).NEXT_INDEX = 8
            Let COMMAND_LINES(8).CURRENT_LINE_NBR = 8
            Let COMMAND_LINES(8).PREVIOUS_INDEX = 7
            Let COMMAND_LINES(8).NEXT_INDEX = 9
            Let COMMAND_LINES(9).CURRENT_LINE_NBR = 9
            Let COMMAND_LINES(9).PREVIOUS_INDEX = 8
            Let COMMAND_LINES(9).NEXT_INDEX = 10
            Let COMMAND_LINES(10).CURRENT_LINE_NBR = 10
            Let COMMAND_LINES(10).PREVIOUS_INDEX = 9
            Let COMMAND_LINES(10).NEXT_INDEX = 11
            Let COMMAND_LINES(11).CURRENT_LINE_NBR = 11
            Let COMMAND_LINES(11).PREVIOUS_INDEX = 10
            Let COMMAND_LINES(11).NEXT_INDEX = 12
            Let COMMAND_LINES(12).CURRENT_LINE_NBR = 12
            Let COMMAND_LINES(12).PREVIOUS_INDEX = 11
            Let COMMAND_LINES(12).NEXT_INDEX = 1
        End Response

        Internal Response DO_RECALL_DEMO
            Remove All
            Display
                INFO_PANEL on INFO_VP
            If (STYLE = "VMS") Then
                Activate
                    Panel VMS_PANEL
            End If
            If (STYLE = "CRC") Then
                Activate
                    Panel CRC_PANEL
            End If
            Position To Next Item
        End Response

        Internal Response RESTART_DEMO
            Let COMMAND_INDEX = 1
            Let COMMAND_POINTER = 1
            Activate
                Panel MENU_PANEL
            Position To First Item
        End Response

        Enable Response
            Include SETUP_SCROLL_CONTROL
            Include RESTART_DEMO
        End Response

        Function Response DO_IT_AGAIN
            Message
                " "
            Include RESTART_DEMO
        End Response

        Function Response CLEAR_MESSAGE_AREA
            Message
                ""
        End Response

        Function Response NEXT PANEL
        End Response

        Function Response PREVIOUS PANEL
        End Response

        Function Response SHOW_VALUES
            If (STYLE = "VMS") Then
                Message
                    "command index = "
                    COMMAND_INDEX
                    " command ptr = "
                    COMMAND_POINTER
            Else
                Message
                    "command index = "
                    COMMAND_INDEX
            End If
        End Response

        Function Response INIT_COMMANDS
            Let COMMAND_LINES(1).COMMAND_LINE_1 = "Form Develop Account "-
                "/output=(IFDL,form=New_Account)/panel=address"
            Let COMMAND_LINES(1).COMMAND_LINE_2 = "/checkpoint=new_account"
            Let COMMAND_LINES(2).COMMAND_LINE_1 = "Form Edit Inventory "-
                "/command=user$disk:[project.common]ped_modify"
            Let COMMAND_LINES(2).COMMAND_LINE_2 = "/panel=authorize"
            Let COMMAND_LINES(3).COMMAND_LINE_1 = "Form Translate Order_entry "-
                "/diagnostics/output=user$disk:[smith.devel"
            Let COMMAND_LINES(3).COMMAND_LINE_2 = "op]order_entry_test"
            Let COMMAND_LINES(4).COMMAND_LINE_1 = "Form Extract Object "-
                "Account /layout=French /list /object=user$disk:[j"
            Let COMMAND_LINES(4).COMMAND_LINE_2 = "ones.forms.obj]"
            Let COMMAND_LINES(5).COMMAND_LINE_1 = ""
            Let COMMAND_LINES(5).COMMAND_LINE_2 = ""
            If (STYLE = "VMS") Then
                Let COMMAND_LINE_1 = ""
                Let COMMAND_LINE_2 = ""
            End If
            Let COMMAND_INDEX = 5
            Let COMMAND_POINTER = 5
        End Response

        Function Response CLEAR_COMMANDS
            Reset
                COMMAND_LINES
            Include SETUP_SCROLL_CONTROL
        End Response


        Panel CRC_PANEL
            Viewport SELECT_LINE_VIEW
            /* 
Style = "CRC":

   Provide command recall on up to 16 lines using a circular buffer in the
   form. The items previous_index and next_index are not displayed on the
   screen but are used to change the value of the command_index. This method
   does away with the need for calling a procedural escape which would
   otherwise be needed to do a plus/minus 1 calculation.

   

   The command input area is two lines where getting to the end of the first
   line causes autoskip to the second line. This 2 line display provides up
   to 149 characters of command. This "restriction" is merely due to wanting
   to keep to only 2 lines on the display. It could be extended easily by
   adding an additional line to the group.
*/
            Entry Response
                Let COMMAND_INDEX = 1
            End Response

            Function Response DO_COMMAND
                Let COMMAND_CHARS = COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1
                Message
                    "command beginning >"
                    COMMAND_CHARS
                    "< has been dispatched."
                Let COMMAND_INDEX = COMMAND_LINES(COMMAND_INDEX).NEXT_INDEX
                Reset
                    COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1
                Reset
                    COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_2
                Position To Field COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1 
                    On CRC_PANEL
            End Response

            Function Response COMMAND_UP
                Let COMMAND_INDEX = COMMAND_LINES(COMMAND_INDEX).PREVIOUS_INDEX
                Position To Field COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1 
                    On CRC_PANEL
            End Response

            Function Response COMMAND_DOWN
                Let COMMAND_INDEX = COMMAND_LINES(COMMAND_INDEX).NEXT_INDEX
                Position To Field COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1 
                    On CRC_PANEL
            End Response

            Group COMMAND_LINES
                Vertical
                    Displays 1
                    First COMMAND_INDEX
                /* 
   The literal is inside the group so that a full two lines are scrolled.
   This is more efficient in that we can use hardware scrolling where that 
   is available in the terminal.
*/
                Literal Text
                    Line 1
                    Column 1
                    Value "Selection>"
                End Literal

                Field COMMAND_LINE_1
                    Same Line
                    Column 12
                    Function Response BOUNDARY CURSOR RIGHT
                        Position Immediate To Next Item
                    End Response

                    Autoskip
                    Output Picture X(69)
                End Field

                Field COMMAND_LINE_2
                    Next Line
                    Column 1
                    Function Response BOUNDARY CURSOR LEFT
                        Position Immediate To Previous Item
                    End Response

                    Output Picture X(80)
                End Field

            End Group

        End Panel


        Panel VMS_PANEL
            Viewport SELECT_LINE_VIEW
            /* 
Style = "VMS":

   Provide command recall on up to 16 lines using VMS_style command recall.
   The previous/next index are used to maintain an internal pointer which
   is then used to move a command from the internal buffer to the display
   area.
   

   The command input area is two lines where getting to the end of the first
   line causes autoskip to the second line. This 2 line display provides up
   to 149 characters of command. This "restriction" is merely due to wanting
   to keep to only 2 lines on the display. It could be extended easily by
   adding an additional line to the group.
*/
            Entry Response
                Let COMMAND_INDEX = 1
                Let COMMAND_POINTER = 1
            End Response

            Function Response DO_COMMAND
                Let COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1 = COMMAND_LINE_1
                Let COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_2 = COMMAND_LINE_2
                Let COMMAND_CHARS = COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1
                Message
                    "command beginning >"
                    COMMAND_CHARS
                    "< has been dispatched."
                Let COMMAND_POINTER = COMMAND_LINES(COMMAND_INDEX).NEXT_INDEX
                Let COMMAND_INDEX = COMMAND_LINES(COMMAND_INDEX).NEXT_INDEX
                Reset
                    COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_1
                Reset
                    COMMAND_LINES(COMMAND_INDEX).COMMAND_LINE_2
                Reset
                    COMMAND_LINE_1
                Reset
                    COMMAND_LINE_2
                Position To Field COMMAND_LINE_1 On VMS_PANEL
            End Response

            Function Response COMMAND_UP
                Let COMMAND_POINTER = 
                    COMMAND_LINES(COMMAND_POINTER).PREVIOUS_INDEX
                Let COMMAND_LINE_1 = 
                    COMMAND_LINES(COMMAND_POINTER).COMMAND_LINE_1
                Let COMMAND_LINE_2 = 
                    COMMAND_LINES(COMMAND_POINTER).COMMAND_LINE_2
            End Response

            Function Response COMMAND_DOWN
                Let COMMAND_POINTER = COMMAND_LINES(COMMAND_POINTER).NEXT_INDEX
                Let COMMAND_LINE_1 = 
                    COMMAND_LINES(COMMAND_POINTER).COMMAND_LINE_1
                Let COMMAND_LINE_2 = 
                    COMMAND_LINES(COMMAND_POINTER).COMMAND_LINE_2
            End Response

            Literal Text
                Line 1
                Column 1
                Value "Selection>"
            End Literal

            Field COMMAND_LINE_1
                Same Line
                Column 12
                Function Response BOUNDARY CURSOR RIGHT
                    Position Immediate To Next Item
                End Response

                Autoskip
                Output Picture X(69)
            End Field

            Field COMMAND_LINE_2
                Next Line
                Column 1
                Function Response BOUNDARY CURSOR LEFT
                    Position Immediate To Previous Item
                End Response

                Output Picture X(80)
            End Field

        End Panel


        Panel INFO_PANEL
            Literal Text
                Line 3
                Column 13
                Value "Demonstration of command recall from within a form"
            End Literal

            Field RECALL_STYLE_TEXT
                Line 4
                Column 13
                Output Picture X(50)
                Protected
            End Field

            Literal Text
                Line 6
                Column 1
                Value "The command input area below comprises two lines of "-
                    "entry for a single command."
            End Literal

            Literal Text
                Line 7
                Column 1
                Value 'This allows 149 characters per command. This '-
                    '"restriction" is merely due to the'
            End Literal

            Literal Text
                Line 8
                Column 1
                Value "desire to only use 2 lines on the display."
            End Literal

            Literal Text
                Line 8
                Column 44
                Value "If you want more characters in your"
            End Literal

            Literal Text
                Line 9
                Column 1
                Value "command line then use more lines on the display."
            End Literal

            Literal Text
                Line 11
                Column 1
                Value "Keys:"
            End Literal

            Literal Text
                Line 12
                Column 7
                Value "RETURN simulates going back to the program with the "-
                    "current command"
            End Literal

            Literal Text
                Line 13
                Column 14
                Value "line but really just displays a message and scrolls"
            End Literal

            Literal Text
                Line 14
                Column 7
                Value "F10 exits from the demo"
            End Literal

            Literal Text
                Line 15
                Column 7
                Value "TAB goes to next line of the command"
            End Literal

            Literal Text
                Line 16
                Column 7
                Value "BS  goes to previous line of the command"
            End Literal

            Literal Text
                Line 17
                Column 7
                Value "UP ARROW scrolls to the previous command"
            End Literal

            Literal Text
                Line 18
                Column 7
                Value "DOWN ARROW scrolls to the next command"
            End Literal

            Literal Text
                Line 19
                Column 7
                Value "F18 will setup some sample commands while PF1-F18 will "-
                    "clear the buffer"
            End Literal

            Literal Text
                Line 20
                Column 7
                Value "F19 will re-start the demo. F20 will clear the message "-
                    "line"
            End Literal

        End Panel


        Panel MENU_PANEL
            Viewport MENU_VP
            Function Response MENU_SELECT
                If (STYLE = "VMS") Then
                    Let RECALL_STYLE_TEXT = VMS_STYLE_TEXT
                End If
                If (STYLE = "CRC") Then
                    Let RECALL_STYLE_TEXT = CRC_STYLE_TEXT
                End If
                Include DO_RECALL_DEMO
            End Response

            Literal Text
                Line 4
                Column 9
                Value "This form demonstrates how Groups may be used in "-
                    "DECforms to"
            End Literal

            Literal Text
                Line 5
                Column 9
                Value "provide entry and editing of commands including "-
                    "command recall."
            End Literal

            Literal Text
                Line 7
                Column 9
                Value "There are two types of command recall demonstrated here:"
            End Literal

            Literal Text
                Line 9
                Column 26
                Value "where you may go back to previous commands to select"
            End Literal

            Literal Text
                Line 10
                Column 26
                Value "a new command and then the one you select is added to"
            End Literal

            Literal Text
                Line 11
                Column 26
                Value "the end of the list of selectable commands."
            End Literal

            Literal Text
                Line 13
                Column 26
                Value "where the commands are stored in a circular buffer"
            End Literal

            Literal Text
                Line 14
                Column 25
                Value " and you directly edit the command you select. In this"
            End Literal

            Literal Text
                Line 15
                Column 25
                Value " model, whatever is the next command in the buffer is"
            End Literal

            Literal Text
                Line 16
                Column 25
                Value " then cleared and becomes the next command line."
            End Literal

            Literal Text
                Line 18
                Column 9
                Value "Use the arrow keys to move between the highlighted "-
                    "items and press"
            End Literal

            Literal Text
                Line 19
                Column 9
                Value "Select on the one you would like to see demonstrated."
            End Literal

            Literal Text
                Line 21
                Column 9
                Value "At any time, you may press F10 or cntrl/Z to leave "-
                    "this demo."
            End Literal

            Icon VMS_STYLE
                Entry Response
                    Let STYLE = "VMS"
                End Response

                Active Highlight
                    Bold
                Literal Text
                    Line 9
                    Column 8
                    Value " VMS-style "
                    Display
                        Reverse
                End Literal

            End Icon

            Icon CIRC_BUFFER_STYLE
                Entry Response
                    Let STYLE = "CRC"
                End Response

                Active Highlight
                    Bold
                Literal Text
                    Line 13
                    Column 8
                    Value " Circular buffer "
                    Display
                        Reverse
                End Literal

            End Icon

        End Panel

    End Layout
End Form