#
# Datefield
# ----------------------------------------------------------------------
# Implements a date entry field with adjustable built-in intelligence
# levels.
# ----------------------------------------------------------------------
#   AUTHOR:  Mark L. Ulferts          E-mail: mulferts@austin.dsccc.com
#
#   @(#) $Id: datefield.itk 43163 2011-02-09 15:07:48Z brlcad $
# ----------------------------------------------------------------------
#            Copyright (c) 1997 DSC Technologies Corporation
# ======================================================================
#
# Permission to use, copy, modify, distribute and license this software 
# and its documentation for any purpose, and without fee or written 
# agreement with DSC, is hereby granted, provided that the above copyright 
# notice appears in all copies and that both the copyright notice and 
# warranty disclaimer below appear in supporting documentation, and that 
# the names of DSC Technologies Corporation or DSC Communications 
# Corporation not be used in advertising or publicity pertaining to the 
# software without specific, written prior permission.
# 
# DSC DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING 
# ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, AND NON-
# INFRINGEMENT. THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, AND THE
# AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE MAINTENANCE, 
# SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS. IN NO EVENT SHALL 
# DSC BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR 
# ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, 
# WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTUOUS ACTION,
# ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS 
# SOFTWARE.
# ======================================================================

#
# Usual options.
#
itk::usual Datefield {
    keep -background -borderwidth -cursor -foreground -highlightcolor \
     -highlightthickness -labelfont -textbackground -textfont 
}

# ------------------------------------------------------------------
#                               DATEFIELD
# ------------------------------------------------------------------
itcl::class iwidgets::Datefield {
    inherit iwidgets::Labeledwidget 
    
    constructor {args} {}

    itk_option define -childsitepos childSitePos Position e
    itk_option define -command command Command {}
    itk_option define -iq iq Iq high
    itk_option define -gmt gmt GMT no
    itk_option define -int int DateFormat no
    
    public method get {{format "-string"}}
    public method isvalid {}
    public method show {{date now}}

    protected method _backward {}
    protected method _focusIn {}
    protected method _forward {}
    protected method _keyPress {char sym state}
    protected method _lastDay {month year}
    protected method _moveField {direction}
    protected method _setField {field}
    protected method _whichField {}

    protected variable _cfield "month"
    protected variable _fields {month day year}
}


#
# Provide a lowercased access method for the datefield class.
# 
proc ::iwidgets::datefield {pathName args} {
    uplevel ::iwidgets::Datefield $pathName $args
}

#
# Use option database to override default resources of base classes.
#
option add *Datefield.justify center widgetDefault

# ------------------------------------------------------------------
#                        CONSTRUCTOR
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::constructor {args} {
    component hull configure -borderwidth 0
    
    #   
    # Create an entry field for entering the date.
    #   
    itk_component add date {
    entry $itk_interior.date -width 10
    } {
    keep -borderwidth -cursor -exportselection \
        -foreground -highlightcolor -highlightthickness \
        -insertbackground -justify -relief -state
    
    rename -font -textfont textFont Font
    rename -highlightbackground -background background Background
    rename -background -textbackground textBackground Background
    }

    #
    # Create the child site widget.
    #
    itk_component add -protected dfchildsite {
    frame $itk_interior.dfchildsite
    } 
    set itk_interior $itk_component(dfchildsite)
    
    #
    # Add datefield event bindings for focus in and keypress events.
    #
    bind $itk_component(date) <FocusIn> [itcl::code $this _focusIn]
    bind $itk_component(date) <KeyPress> [itcl::code $this _keyPress %A %K %s]
    
    #
    # Disable some mouse button event bindings:
    #   Button Motion
    #   Double-Clicks
    #   Triple-Clicks
    #   Button2
    #
    bind $itk_component(date) <Button1-Motion>  break
    bind $itk_component(date) <Button2-Motion>  break
    bind $itk_component(date) <Double-Button>   break
    bind $itk_component(date) <Triple-Button>   break
    bind $itk_component(date) <2>       break

    #
    # Initialize the widget based on the command line options.
    #
    eval itk_initialize $args

    #
    # Initialize the date to the current date.
    #
    $itk_component(date) delete 0 end

    show now
}

# ------------------------------------------------------------------
#                             OPTIONS
# ------------------------------------------------------------------

# ------------------------------------------------------------------
# OPTION: -childsitepos
#
# Specifies the position of the child site in the widget.  Valid
# locations are n, s, e, and w.
# ------------------------------------------------------------------
itcl::configbody iwidgets::Datefield::childsitepos {
    set parent [winfo parent $itk_component(date)]

    switch $itk_option(-childsitepos) {
    n {
        grid $itk_component(dfchildsite) -row 0 -column 0 -sticky ew
        grid $itk_component(date) -row 1 -column 0 -sticky nsew

        grid rowconfigure $parent 0 -weight 0
        grid rowconfigure $parent 1 -weight 1
        grid columnconfigure $parent 0 -weight 1
        grid columnconfigure $parent 1 -weight 0
    }
    
    e {
        grid $itk_component(dfchildsite) -row 0 -column 1 -sticky ns
        grid $itk_component(date) -row 0 -column 0 -sticky nsew

        grid rowconfigure $parent 0 -weight 1
        grid rowconfigure $parent 1 -weight 0
        grid columnconfigure $parent 0 -weight 1
        grid columnconfigure $parent 1 -weight 0
    }
    
    s {
        grid $itk_component(dfchildsite) -row 1 -column 0 -sticky ew
        grid $itk_component(date) -row 0 -column 0 -sticky nsew

        grid rowconfigure $parent 0 -weight 1
        grid rowconfigure $parent 1 -weight 0
        grid columnconfigure $parent 0 -weight 1
        grid columnconfigure $parent 1 -weight 0
    }
    
    w {
        grid $itk_component(dfchildsite) -row 0 -column 0 -sticky ns
        grid $itk_component(date) -row 0 -column 1 -sticky nsew

        grid rowconfigure $parent 0 -weight 1
        grid rowconfigure $parent 1 -weight 0
        grid columnconfigure $parent 0 -weight 0
        grid columnconfigure $parent 1 -weight 1
    }
    
    default {
        error "bad childsite option\
            \"$itk_option(-childsitepos)\":\
            should be n, e, s, or w"
    }
    }
}

# ------------------------------------------------------------------
# OPTION: -command
#
# Command invoked upon detection of return key press event.
# ------------------------------------------------------------------
itcl::configbody iwidgets::Datefield::command {}

# ------------------------------------------------------------------
# OPTION: -iq
#
# Specifies the level of intelligence to be shown in the actions
# taken by the date field during the processing of keypress events.
# Valid settings include high, average, and low.  With a high iq,
# the date prevents the user from typing in an invalid date.  For 
# example, if the current date is 05/31/1997 and the user changes
# the month to 04, then the day will be instantly modified for them 
# to be 30.  In addition, leap years are fully taken into account.
# With average iq, the month is limited to the values of 01-12, but
# it is possible to type in an invalid day.  A setting of low iq
# instructs the widget to do no validity checking at all during
# date entry.  With both average and low iq levels, it is assumed
# that the validity will be determined at a later time using the
# date's isvalid command.
# ------------------------------------------------------------------
itcl::configbody iwidgets::Datefield::iq {
    switch $itk_option(-iq) {
    high - average - low {
    }
    default {
        error "bad iq option \"$itk_option(-iq)\":\
                   should be high, average or low"
    }
    }
}

# ------------------------------------------------------------------
# OPTION: -int 
#
# Added by Mark Alston 2001/10/21
#
# Allows for the use of dates in "international" format: YYYY-MM-DD.
# It must be a boolean value.
# ------------------------------------------------------------------
itcl::configbody iwidgets::Datefield::int { 
    switch $itk_option(-int) {
    1 - yes - true - on {
        set _cfield "year"
        set _fields {year month day}
    }
    0 - no - false - off { }
    default {
        error "bad int option \"$itk_option(-int)\": should be boolean"
    }
    }
    show [get]
}

# ------------------------------------------------------------------
# OPTION: -gmt
#
# This option is used for GMT time.  Must be a boolean value.
# ------------------------------------------------------------------
itcl::configbody iwidgets::Datefield::gmt {
  switch $itk_option(-gmt) {
    0 - no - false - off { }
    1 - yes - true - on { }
    default {
      error "bad gmt option \"$itk_option(-gmt)\": should be boolean"
    }
  }
}

# ------------------------------------------------------------------
#                            METHODS
# ------------------------------------------------------------------

# ------------------------------------------------------------------
# PUBLIC METHOD: get ?format?
#
# Return the current contents of the datefield in one of two formats
# string or as an integer clock value using the -string and -clicks
# options respectively.  The default is by string.  Reference the 
# clock command for more information on obtaining dates and their 
# formats.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::get {{format "-string"}} {
    set datestr [$itk_component(date) get]

    switch -- $format {
    "-string" {
        return $datestr
    }
    "-clicks" {
        return [clock scan $datestr]
    }
    default {
        error "bad format option \"$format\":\
                   should be -string or -clicks"
    }
    }
}

# ------------------------------------------------------------------
# PUBLIC METHOD: show date
#
# Changes the currently displayed date to be that of the date 
# argument.  The date may be specified either as a string or an
# integer clock value.  Reference the clock command for more 
# information on obtaining dates and their formats.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::show {{date "now"}} {
    $itk_component(date) delete 0 end
    if {$itk_option(-int)} {
        set format {%Y-%m-%d}
    } else {
        set format {%m/%d/%Y}
    }

    if {$date == "now"} {
        set seconds [::clock seconds]
        $itk_component(date) insert end \
            [clock format $seconds -format "$format" -gmt $itk_option(-gmt)]

    } elseif { $itk_option(-iq) != "low" } {
        if {[catch {::clock format $date}] == 0} {
            set seconds $date
        } elseif {[catch {set seconds [::clock scan $date -gmt \
                $itk_option(-gmt)]}] != 0} {
            error "bad date: \"$date\", must be a valid date\
            string, clock clicks value or the keyword now"
        }
        $itk_component(date) insert end \
            [clock format $seconds -format "$format" -gmt $itk_option(-gmt)]
    } else {
        # Note that it doesn't matter what -int is set to.
        $itk_component(date) insert end $date
    }

    if {$itk_option(-int)} {
        _setField year
    } else {
        _setField month
    }

    return
}

# ------------------------------------------------------------------
# PUBLIC METHOD: isvalid
#
# Returns a boolean indication of the validity of the currently
# displayed date value.  For example, 3/3/1960 is valid whereas
# 02/29/1997 is invalid.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::isvalid {} {
    if {[catch {clock scan [$itk_component(date) get]}] != 0} {
        return 0
    } else {
        return 1
    }
}

# ------------------------------------------------------------------
# PROTECTED METHOD: _focusIn
#
# This method is bound to the <FocusIn> event.  It resets the 
# insert cursor and field settings to be back to their last known
# positions.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_focusIn {} {
    _setField $_cfield
}

# ------------------------------------------------------------------
# PROTECTED METHOD: _keyPress 
#
# This method is the workhorse of the class.  It is bound to the
# <KeyPress> event and controls the processing of all key strokes.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_keyPress {char sym state} {
    #
    #  Determine which field we are in currently.  This is needed
    # since the user may have moved to this position via a mouse
    # selection and so it would not be in the position we last 
    # knew it to be.
    #
    _whichField 

    #
    # If we are using an international date the split char is "-" 
    # otherwise it is "/".
    #
    if {$itk_option(-int)} {
        set split_char "-"
    } else {
        set split_char "/"
    }


    #
    # Set up a few basic variables we'll be needing throughout the
    # rest of the method such as the position of the insert cursor
    # and the currently displayed day, month, and year.
    #
    set icursor [$itk_component(date) index insert]
    set splist [split [$itk_component(date) get] "$split_char"]


    # A bunch of added variables to allow for the use of int dates
    if {$itk_option(-int)} {
        set order {year month day}
        set year [lindex $splist 0]
        set month [lindex $splist 1]
        set day [lindex $splist 2]
        set year_start_pos 0
        set year_second_pos 1
        set year_third_pos 2
        set year_fourth_pos 3
        set year_end_pos 4
        set month_start_pos 5
        set month_second_pos 6
        set month_end_pos 7
        set day_start_pos 8
        set day_second_pos 9
        set day_end_pos 10
    } else {
        set order {month day year}
        set month [lindex $splist 0]
        set day [lindex $splist 1]
        set year [lindex $splist 2]
        set month_start_pos 0
        set month_second_pos 1
        set month_end_pos 2
        set day_start_pos 3
        set day_second_pos 4
        set day_end_pos 5
        set year_start_pos 6
        set year_second_pos 7
        set year_third_pos 8
        set year_fourth_pos 9
        set year_end_pos 10
    }


    #
    # Process numeric keystrokes.  This involes a fair amount of 
    # processing with step one being to check and make sure we
    # aren't attempting to insert more that 10 characters.  If
    # so ring the bell and break.
    #
    if {[string match {[0-9]} $char]} {
        if {[$itk_component(date) index insert] == 10} {
            bell
            return -code break
        }

        #
        # If we are currently in the month field then we process the
        # number entered based on the cursor position.  If we are at
        # at the first position and our iq is low, then accept any 
        # input.
        #
        if {$_cfield == "month"} {

            if {[$itk_component(date) index insert] == $month_start_pos} {
                if {$itk_option(-iq) == "low"} {
                $itk_component(date) delete $month_start_pos
                $itk_component(date) insert $month_start_pos $char
            } else {
                #
                # Otherwise, we're slightly smarter.  If the number
                # is less than two insert it at position zero.  If 
                # this makes the month greater than twelve, set the 
                # number at position one to zero which makes in 
                # effect puts the month back in range.  
                #
                regsub {([0-9])([0-9])} $month "$char\\2" month2b

                if {$char < 2} {
                    $itk_component(date) delete $month_start_pos
                    $itk_component(date) insert $month_start_pos $char

                    if {$month2b > 12} {
                        $itk_component(date) delete $month_second_pos
                        $itk_component(date) insert $month_second_pos 0
                        $itk_component(date) icursor $month_second_pos
                    } elseif {$month2b == "00"} {
                        $itk_component(date) delete $month_second_pos
                        $itk_component(date) insert $month_second_pos 1
                        $itk_component(date) icursor $month_second_pos
                    }

                    #
                    # Finally, if the number is greater than one we'll 
                    # assume that they really mean to be entering a zero
                    # followed by their number, do so for them, and 
                    # proceed to skip to the next field which is the 
                    # day field.
                    #
                } else {
                    $itk_component(date) delete $month_start_pos $month_end_pos
                    $itk_component(date) insert $month_start_pos 0$char
                    _setField day
                }
            }
            
            #
            # Else, we're at the second month position.  Again, if we aren't
            # too smart, let them enter anything.  Otherwise, if the 
            # number makes the month exceed twelve, set the month to
            # zero followed by their number to get it back into range.
            #
        } else {
            regsub {([0-9])([0-9])} $month "\\1$char" month2b
        
            if {$itk_option(-iq) == "low"} {
                $itk_component(date) delete $month_second_pos
                $itk_component(date) insert $month_second_pos $char
            } else {
                if {$month2b > 12} {
                    $itk_component(date) delete $month_start_pos $month_end_pos
                    $itk_component(date) insert $month_start_pos 0$char
                } elseif {$month2b == "00"} {
                    bell
                    return -code break
                } else {
                    $itk_component(date) delete $month_second_pos
                    $itk_component(date) insert $month_second_pos $char
                }           
            }
            _setField day
        }

        # 
        # Now, the month processing is complete and if we're of a
        # high level of intelligence, then we'll make sure that the
        # current value for the day is valid for this month.  If
        # it is beyond the last day for this month, change it to
        # be the last day of the new month.
        #
        if {$itk_option(-iq) == "high"} {
            set splist [split [$itk_component(date) get] "$split_char"]
            set month [lindex $splist [lsearch $order month]]
            if {$day > [set endday [_lastDay $month $year]]} {
                set icursor [$itk_component(date) index insert]
                $itk_component(date) delete $day_start_pos $day_end_pos
                $itk_component(date) insert $day_start_pos $endday
                $itk_component(date) icursor $icursor
            }
        }
        
        #
        # Finally, return with a code of break to stop any normal
        # processing in that we've done all that is necessary.
        #
        return -code break
    }

    #
    # This next block of code is for processing of the day field
    # which is quite similar is strategy to that of the month.
    #
    if {$_cfield == "day"} {
        if {$itk_option(-iq) == "high"} {
            set endofMonth [_lastDay $month $year]
        } else {
            set endofMonth 31
        }

        #
        # If we are at the first cursor position for the day 
        # we are processing 
        # the first character of the day field.  If we have an iq 
        # of low accept any input.
        #
        if {[$itk_component(date) index insert] == $day_start_pos} {
            if {$itk_option(-iq) == "low"} {
                $itk_component(date) delete $day_start_pos
                $itk_component(date) insert $day_start_pos $char
            
            } else {

                #
                # If the day to be is double zero, then make the
                # day be the first.
                #
                regsub {([0-9])([0-9])} $day "$char\\2" day2b

                if {$day2b == "00"} {
                    $itk_component(date) delete $day_start_pos $day_end_pos
                    $itk_component(date) insert $day_start_pos 01
                    $itk_component(date) icursor $day_second_pos
                    #
                    # Otherwise, if the character is less than four 
                    # and the month is not Feburary, insert the number 
                    # and if this makes the day be beyond the valid 
                    # range for this month, than set to be back in 
                    # range.  
                    #
                } elseif {($char < 4) && ($month != "02")} {
                    $itk_component(date) delete $day_start_pos
                    $itk_component(date) insert $day_start_pos $char
            
                    if {$day2b > $endofMonth} {
                        $itk_component(date) delete $day_second_pos
                        $itk_component(date) insert $day_second_pos 0
                        $itk_component(date) icursor $day_second_pos
                    } 
            
                    #
                    # For Feburary with a number to be entered of 
                    # less than three, make sure the number doesn't 
                    # make the day be greater than the correct range
                    # and if so adjust the input. 
                    #
                } elseif {$char < 3} {
                    $itk_component(date) delete $day_start_pos
                    $itk_component(date) insert $day_start_pos $char
                    if {$day2b > $endofMonth} {
                        $itk_component(date) delete $day_start_pos $day_end_pos
                        $itk_component(date) insert $day_start_pos $endofMonth
                        $itk_component(date) icursor $day_second_pos
                    } 

                    #
                    # Finally, if the number is greater than three,
                    # set the day to be zero followed by the number 
                    # entered and proceed to the year field or end.
                    #
                } else {
                    $itk_component(date) delete $day_start_pos $day_end_pos
                    $itk_component(date) insert $day_start_pos 0$char
                    $itk_component(date) icursor $day_end_pos
                    if {!$itk_option(-int)} {
                        _setField year
                    }
                }
            }
            #
            # Else, we're dealing with the second number in the day
            # field.  If we're not too bright accept anything, otherwise
            # if the day is beyond the range for this month or equal to
            # zero then ring the bell.
            #
        } else {
            regsub {([0-9])([0-9])} $day "\\1$char" day2b
        
            if {($itk_option(-iq) != "low") && \
                (($day2b > $endofMonth) || ($day2b == "00"))} {
                bell
            } else {
                $itk_component(date) delete $day_second_pos
                $itk_component(date) insert $day_second_pos $char
                $itk_component(date) icursor $day_end_pos
                if {!$itk_option(-int)} {
                    _setField year
                }
            }
        }

        #
        # Return with a code of break to prevent normal processing. 
        #
        return -code break
    }

    #
    # This month and day we're tough, the code for the year is 
    # comparitively simple.  Accept any input and if we are really
    # sharp, then make sure the day is correct for the month
    # given the year.  In short, handle leap years.
    #
    if {$_cfield == "year"} {
        if {$itk_option(-iq) == "low"} {
            $itk_component(date) delete $icursor
            $itk_component(date) insert $icursor $char
        } else {
            set prevdate [get]
            if {[$itk_component(date) index insert] == $year_start_pos} {
                set yrdgt [lindex [split [lindex \
                [split $prevdate "$split_char"] [lsearch $order year]] ""] 0]
                if {$char != $yrdgt} {
                    if {$char == 1} {
                        $itk_component(date) delete $icursor $year_end_pos
                        $itk_component(date) insert $icursor 1999
                    } elseif {$char == 2} {
                        $itk_component(date) delete $icursor $year_end_pos
                        $itk_component(date) insert $icursor 2000
                    } else {
                        bell
                        return -code break
                    }
                }

                $itk_component(date) icursor $year_second_pos
                return -code break
            }
        
            $itk_component(date) delete $icursor
            $itk_component(date) insert $icursor $char


            if {[catch {clock scan [get]}] != 0} {
                $itk_component(date) delete $year_start_pos $year_end_pos
                $itk_component(date) insert $year_start_pos \
                [lindex [split $prevdate "$split_char"] [lsearch $order year]]
                $itk_component(date) icursor $icursor

                bell
                return -code break
            }

            if {$itk_option(-iq) == "high"} {
                set splist [split [$itk_component(date) get] "$split_char"]
                set year [lindex $splist [lsearch $order year]]

                if {$day > [set endday [_lastDay $month $year]]} {
                    set icursor [$itk_component(date) index insert]
                    $itk_component(date) delete $day_start_pos $day_end_pos
                    $itk_component(date) insert $day_start_pos $endday
                    $itk_component(date) icursor $icursor
                }
            }
        }
        if {$itk_option(-int)} {
            if {$icursor == $year_fourth_pos } {
                _setField month
            }
        }
        return -code break
    }
    
    #
    # Process the plus and the up arrow keys.  They both yeild the same
    # effect, they increment the day by one.
    #
    } elseif {($sym == "plus") || ($sym == "Up")} {
        if {[catch {show [clock scan "1 day" -base [get -clicks]]}] != 0} {
            bell
        }
        return -code break
    
        #
        # Process the minus and the down arrow keys which decrement the day.
        #
    } elseif {($sym == "minus") || ($sym == "Down")} {
        if {[catch {show [clock scan "-1 day" -base [get -clicks]]}] != 0} {
            bell
        }
        return -code break

        #
        # A tab key moves the day/month/year (or year/month/day) field
        # forward by one unless
        # the current field is the last field.  In that case we'll let tab
        # do what is supposed to and pass the focus onto the next widget.
        #
    } elseif {($sym == "Tab") && ($state == 0)} {
        if {$_cfield != "[lindex $order 2]"} {
            _moveField forward
            return -code break
        } else {
            _setField "[lindex $order 0]"
            return -code continue
        }

        #
        # A ctrl-tab key moves the day/month/year field backwards by one 
        # unless the current field is the the first field.  In that case we'll
        # let tab take the focus to a previous widget.
        #
    } elseif {($sym == "Tab") && ($state == 4)} {
        if {$_cfield != "[lindex $order 0]"} {
            _moveField backward
            return -code break
        } else {
            set _cfield "[lindex $order 0]"
            return -code continue
        }

        #
        # A right arrow key moves the insert cursor to the right one.
        #
    } elseif {$sym == "Right"} {
        _forward
        return -code break

        #
        # A left arrow, backspace, or delete key moves the insert cursor 
        # to the left one.  This is what you expect for the left arrow
        # and since the whole widget always operates in overstrike mode,
        # it makes the most sense for backspace and delete to do the same.
        #
    } elseif {$sym == "Left" || $sym == "BackSpace" || $sym == "Delete"} {
        _backward
        return -code break

    } elseif {($sym == "Control_L") || ($sym == "Shift_L") || \
            ($sym == "Control_R") || ($sym == "Shift_R")} {
        return -code break

        #
        # A Return key invokes the optionally specified command option.
        #
    } elseif {$sym == "Return"} {
        uplevel #0 $itk_option(-command)
        return -code break 
    } else {
        bell
        return -code break
    }
}

# ------------------------------------------------------------------
# PROTECTED METHOD: _setField field
#
# Internal method which adjusts the field to be that of the 
# argument, setting the insert cursor appropriately.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_setField {field} {
    set _cfield $field
    
    if {$itk_option(-int)} {
        set year_pos 2
        set month_pos 5
        set day_pos 8
    } else {
        set month_pos 0
        set day_pos 3
        set year_pos 8
    }

    switch $field {
        "month" {
            $itk_component(date) icursor $month_pos
        }
        "day" {
            $itk_component(date) icursor $day_pos
        }
        "year" {
            $itk_component(date) icursor $year_pos
        }
        default {
            error "bad field: \"$field\", must be month, day or year"
        }
    }
}

# ------------------------------------------------------------------
# PROTECTED METHOD: _moveField
#
# Internal method for moving the field forward or backward by one.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_moveField {direction} {

    set index [lsearch $_fields $_cfield]

    if {$direction == "forward"} {
        set newIndex [expr {$index + 1}]
    } else {
        set newIndex [expr {$index - 1}]
    }

    if {$newIndex == [llength $_fields]} {
        set newIndex 0
    }
    if {$newIndex < 0} {
        set newIndex [expr {[llength $_fields] - 1}]
    }

    _setField [lindex $_fields $newIndex]

    return
}

# ------------------------------------------------------------------
# PROTECTED METHOD: _whichField
#
# Internal method which returns the current field that the cursor
# is currently within.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_whichField {} {
    set icursor [$itk_component(date) index insert]

    if {$itk_option(-int)} {
        switch $icursor {
            0 - 1 - 2 - 3 {
                set _cfield "year"
            }
            5 - 6 {
                set _cfield "month"
            }
            8 - 9 {
                set _cfield "day"
            }
        }
    } else {
        switch $icursor {
            0 - 1 {
            set _cfield "month"
            }
            3 - 4 {
            set _cfield "day"
            }
            6 - 7 - 8 - 9 {
            set _cfield "year"
            }
        }
    }
}

# ------------------------------------------------------------------
# PROTECTED METHOD: _forward
#
# Internal method which moves the cursor forward by one character
# jumping over the slashes and wrapping.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_forward {} {
    set icursor [$itk_component(date) index insert]

    if {$itk_option(-int)} {
        switch $icursor {
            3 {
                _setField month
            }
            6 {
            _setField day
            }
            9 - 10 {
            _setField year
            }
            default {
            $itk_component(date) icursor [expr {$icursor + 1}]
            }
        }
    } else {
        switch $icursor {
            1 {
            _setField day
            }
            4 {
            _setField year
            }
            9 - 10 {
            _setField month
            }
            default {
            $itk_component(date) icursor [expr {$icursor + 1}]
            }
        }
    }
}

# ------------------------------------------------------------------
# PROTECTED METHOD: _backward
#
# Internal method which moves the cursor backward by one character
# jumping over the slashes and wrapping.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_backward {} {
    set icursor [$itk_component(date) index insert]
    if {$itk_option(-int)} {
        switch $icursor {
            8 {
            _setField month
            }
            5 {
            _setField year
            }
            0 {
            _setField day
            }
            default {
            $itk_component(date) icursor [expr {$icursor -1}]
            }
        }
    } else {
        switch $icursor {
            6 {
                _setField day
            }
            3 {
                _setField month
            }
            0 {
                _setField year
            }
            default {
                $itk_component(date) icursor [expr {$icursor -1}]
            }
        }
    }
}

# ------------------------------------------------------------------
# PROTECTED METHOD: _lastDay month year
#
# Internal method which determines the last day of the month for
# the given month and year.  We start at 28 and go forward till
# we fail.  Crude but effective.
# ------------------------------------------------------------------
itcl::body iwidgets::Datefield::_lastDay {month year} {
    set lastone 28

    for {set lastone 28} {$lastone < 32} {incr lastone} {
        set nextone [expr $lastone + 1]
        if {[catch {clock scan $month/$nextone/$year}] != 0} {
            return $lastone
        }
    }
}