# Tag Handlers for the ArsDigita Templating System

# Copyright (C) 1999-2000 ArsDigita Corporation
# Authors: Karl Goldstein    	  (karlg@arsdigita.com)
#          Stanislav Freidin 	  (sfreidin@arsdigita.com)
#          Christian Brechbuehler (chrisitan@arsdigita.com)

# $Id: tag-init.tcl,v 1.28.2.1 2008/02/02 19:45:33 emmar Exp $

# This is free software distributed under the terms of the GNU Public
# License.  Full text of the license is available from the GNU Project:
# http://www.fsf.org/copyleft/gpl.html

#-----------------------------------------------------------
# Putting tag handlers in namespaces does not seem to work!
#-----------------------------------------------------------

# Add some escaped Tcl

template_tag tcl { chunk params } {

  # if the chunk begins with = then add our own append
  if { [string index $chunk 0] == "=" } {
    template::adp_append_code "append __adp_output [string range $chunk 1 end]"
  } else {
    template::adp_append_code $chunk
  }
}

# Set a property for the template.  Properties are primarily for the
# benefit of the master template to display appropriate context,
# such as the title, navigation links, etc.

template_tag property { chunk params } {

  set name [ns_set iget $params name]

  # quote dollar signs, square bracket and quotes
  regsub -all {[\]\[""\\$]} $chunk {\\&} quoted_chunk

  template::adp_append_code "set __adp_properties($name) \"$quoted_chunk\""
}

# Set the master template.

template_tag master { params } {

  set src [ns_set iget $params src]
  set slave_properties_p [template::get_attribute multiple $params slave-properties-p 0]

  if {[template::util::is_true $slave_properties_p]} {
    template::adp_append_code "
      foreach {__key __value} \$__args {
        if {!\[string equal \$__key __adp_slave\]} {
          set __adp_properties(\$__key) \"\$__value\"
        }
      }
    "
  }

  # default to the site-wide master
  if {$src eq ""} {
    set src "\[ad_parameter -package_id \[ad_conn subsite_id\]\
             DefaultMaster dummy \"/www/default-master\"\]"
  }
  
  template::adp_append_code "
    set __adp_master \[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]"
}

# Insert the slave template

template_tag slave { params } {

  #Start developer support frame around subordinate template.
  if { [llength [info procs ::ds_enabled_p]] && [llength [info procs ::ds_adp_start_box]] } {
      ::ds_adp_start_box
  }

  template::adp_append_code "
    if { \[info exists __adp_slave\] } {
      append __adp_output \$__adp_slave
    }
  "

  #End developer support frame around subordinate template.
  if { [llength [info procs ::ds_enabled_p]] && [llength [info procs ::ds_adp_end_box]] } {
      ::ds_adp_end_box
  }

}

# Include another template in the current template

template_tag include { params } {

  set src [ns_set iget $params src]

  #Start developer support frame around subordinate template.
  if { [llength [info procs ::ds_enabled_p]] && [llength [info procs ::ds_adp_start_box]] } {
      ::ds_adp_start_box -stub "\[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]"
  }

  # pass additional arguments as key-value pairs

  set command "template::adp_parse"
  append command " \[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]"
  append command " \[list"

  for { set i 0 } { $i < [ns_set size $params] } { incr i } {

    set key [ns_set key $params $i]
    if {$key eq "src"} { continue }
    
    set value [ns_set value $params $i]

    append command " $key \"$value\"";	# is $value quoted sufficiently?
  }
  append command "\]"

  # We explicitly test for ad_script_abort, so we don't dump that as an error, and don't catch it, either
  # (We do catch it, but then we re-throw it)
  template::adp_append_code "if { \[catch { append __adp_output \[$command\] } errmsg\] } {"
  template::adp_append_code "    global errorInfo errorCode"
  template::adp_append_code "    if { \[string equal \[lindex \$errorCode 0\] \"AD\"\] && \[string equal \[lindex \$errorCode 1\] \"EXCEPTION\"\] && \[string equal \[lindex \$errorCode 2\] \"ad_script_abort\"\] } {"
  template::adp_append_code "        ad_script_abort"
  template::adp_append_code "    } else {"
  template::adp_append_code "        append __adp_output \"Error in include template \\\"\[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]\\\": \$errmsg\""
  # JCD: If we have the ds_page_bits cache maybe save the error for later
  if { [llength [info procs ::ds_enabled_p]] && [llength [info procs ::ds_page_fragment_cache_enabled_p]] } {
      template::adp_append_code "        if {\[::ds_enabled_p\]"
      template::adp_append_code "            && \[::ds_collection_enabled_p\] } {"
      template::adp_append_code "            set __include_errors {}"
      template::adp_append_code "            ns_cache get ds_page_bits \[ad_conn request\]:error __include_errors"
      template::adp_append_code "            ns_cache set ds_page_bits \[ad_conn request\]:error \[lappend __include_errors \[list \"$src\" \$errorInfo\]\]"
      template::adp_append_code "        }"
  }
  template::adp_append_code "        ns_log Error \"Error in include template \\\"\[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]\\\": \$errmsg\n\$errorInfo\""
  template::adp_append_code "    }"
  template::adp_append_code "}"

  #End developer support frame around subordinate template.
  if { [llength [info procs ::ds_enabled_p]] && [llength [info procs ::ds_adp_end_box]] } {
      ::ds_adp_end_box -stub "\[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]"
  }

}

# Repeat a template chunk for each row of a multirow data source

template_tag multiple { chunk params } {

  set name     [template::get_attribute multiple $params name       ]
  set startrow [template::get_attribute multiple $params startrow  0]
  set maxrows  [template::get_attribute multiple $params maxrows  -1]; #unlimit
  set delimiter [template::get_attribute multiple $params delimiter ""]

  set tag_id [template::current_tag]

  set i "__${tag_id}_i"
  
  template::adp_append_code "

  if {\[info exists $name\]} {
      upvar 0 $name __${tag_id}_swap
  }

  for { set $i [expr {1 + $startrow}] } { \$$i <= \${$name:rowcount}"

  if {$maxrows >= 0} {
    template::adp_append_code " && \$$i <= [expr {$maxrows + $startrow}]" \
	-nobreak
  }
  
  template::adp_append_code " } { incr $i } {
    upvar 0 $name:\$$i $name
  " -nobreak
  template::adp_compile_chunk $chunk

  if { $delimiter ne "" } {
      template::adp_append_code " if { \$$i < \${$name:rowcount}"

      if {$maxrows >= 0} {
	  template::adp_append_code " && \$$i < [expr {$maxrows + $startrow}]" \
	      -nobreak
      }

      template::adp_append_code " } {\n"
      template::adp_append_string $delimiter
      template::adp_append_code "\n}\n"
  }

  template::adp_append_code "}

  if {\[info exists __${tag_id}_swap\]} {
      upvar 0 __${tag_id}_swap $name
  }"
}  

# Repeat a template chunk for each item in a list

template_tag list { chunk params } {

  # the list tag accepts a value so that it may be used without a data
  # source in the tcl script

  set value [ns_set iget $params value]

  # If the value exists, use it and create a fake name for it

  if { ![template::util::is_nil value] } {

    set name [ns_set iget $params name]
    if { $name eq "" } {
      set name "__ats_list_value"
    }

    template::adp_append_code "\nset $name \[eval list $value\]\n"
    template::adp_append_code "\nset $name:rowcount \[llength \$$name\]\n"

  } else {

    # Expect a data source from the tcl script
    set name [template::get_attribute list $params name]
    template::adp_append_code "\nset {$name:rowcount} \[llength \${$name}\]\n"
  }
  
  template::adp_append_code "

  for { set __ats_${name}_i 0 } { \$__ats_${name}_i < \${$name:rowcount} } { incr __ats_${name}_i } {
    set $name:item \[lindex \${$name} \$__ats_${name}_i\]
    set $name:rownum \[expr \$__ats_${name}_i + 1\]
  "
  template::adp_compile_chunk $chunk

  template::adp_append_code "}"
}  

# Create a recursed group, generating a recursive multirow block until the 
# column name stays the same

template_tag group { chunk params } {

  set column [template::get_attribute group $params column]
  set delimiter [template::get_attribute group $params delimiter ""]

  # Scan the parameter stack backward, looking for the tag name

  set multiple_tag_id [template::enclosing_tag multiple]

  if {$multiple_tag_id eq {}} {
    error "No enclosing MULTIPLE tag for GROUP tag on column $column"
  }

  # Get the name of the multiple variable we're looping over
  set name [template::tag_attribute $multiple_tag_id name]

  set tag_id [template::current_tag]

  # If we're inside another group tag, we'll need to save and restore that tag's groupnum and groupnum_last_p values
  # Find enclosing group tag, if one exists
  set group_tag_id [template::enclosing_tag group]

  # Save groupnum pseudocolumns from surrounding group tag
  # We don't care about saving groupnum_last_p, since this doesn't work
  # for group tags that have other group tags inside them, since we can't know
  # if we're the last row until the inner group tag has eaten up all the 
  # rows between the start of this tag and the end.
  if { $group_tag_id ne "" } {
    template::adp_append_code "
      if { \[info exists ${name}(groupnum)\] } {
        set __${tag_id}_${group_tag_id}_groupnum \$${name}(groupnum)
      }
    "
  }

  set i "__${multiple_tag_id}_i"
  
  # while the value of name(column) stays the same
  template::adp_append_code "
    set __${tag_id}_group_rowcount 1
    while { 1 } {
      set ${name}(groupnum) \$__${tag_id}_group_rowcount
      if { \$$i >= \${$name:rowcount} } {
        set ${name}(groupnum_last_p) 1
      } else {
        upvar 0 ${name}:\[expr \$$i + 1\] $name:next 
        set ${name}(groupnum_last_p) \[expr !\[string equal \[set \"${name}:next(${column})\"\] \$${name}($column)\]\]
      }
  "

  template::adp_compile_chunk $chunk     

  # look ahead to the next value and break if it is different
  # otherwise advance the cursor to the next row
  template::adp_append_code "
      if { \$$i >= \${$name:rowcount} } {
        break
      }
      upvar 0 ${name}:\[expr \$$i + 1\] $name:next 
      if { !\[string equal \[set \"${name}:next(${column})\"\] \$${name}(${column})\] } { 
        break
      }
  "

  if { $delimiter ne "" } {
      template::adp_append_string $delimiter
  }

  template::adp_append_code "
      incr $i
      upvar 0 $name:\$$i $name
      incr __${tag_id}_group_rowcount
    }
  "

  # Restore saved groupnum pseudocolumns
  if { $group_tag_id ne "" } {
    template::adp_append_code "
      if { \[info exists __${tag_id}_${group_tag_id}_groupnum\] } {
        set ${name}(groupnum) \$__${tag_id}_${group_tag_id}_groupnum 
      }
    "
  }
}

# Repeat a template chunk consisting of a grid cell for each row of a
# multirow data source

template_tag grid { chunk params } {

  set name [template::get_attribute grid $params name]
  # cols must be a float for ceil to work
  set cols [template::get_attribute grid $params cols]
  # Horizontal or vertical ?
  set orientation [template::get_attribute grid $params orientation vertical]

  template::adp_append_code "
  set rows \[expr {ceil(\${$name:rowcount} / $cols.0)}\]
  for { set __r 1 } { \$__r <= \$rows } { incr __r } {
    for { set __c 1 } { \$__c <= $cols } { incr __c } {
"

  if {$orientation eq "vertical"} {
    template::adp_append_code "
      set rownum \[expr {1 + int((\$__r - 1) + ((\$__c - 1) * \$rows))}\]
"
  } else {
    template::adp_append_code "
      set rownum \[expr {1 + int((\$__c - 1) + ((\$__r - 1) * $cols))}\]
" 
  }

  template::adp_append_code "
      upvar 0 $name:\$rownum $name
      set ${name}(rownum) \$rownum
      set ${name}(row) \$__r
      set ${name}(col) \$__c
  "

  template::adp_compile_chunk $chunk

  template::adp_append_code "
    }
  }"
}

template_tag if { chunk params } {

  template_tag_if_condition $chunk $params if
}

template_tag elseif { chunk params } {

  template_tag_if_condition $chunk $params elseif
}


# Append an "else" clause to the if expression

template_tag else { chunk params } {

  template::adp_append_code "else {" -nobreak

  template::adp_compile_chunk $chunk

  template::adp_append_code "}"  
}

# Output a template chunk without parsing, for preprocessed templates

template_tag noparse { chunk params } {

  # escape quotes
  regsub -all {[\]\[""\\$]} $chunk {\\&} quoted

  template::adp_append_string $quoted
}

# Render the HTML for the form widget, incorporating any additional
# markup attributes specified in the template.

template_tag formwidget { params } {

  set id [template::get_attribute formwidget $params id]

  # get any additional HTML attributes specified by the designer
  set tag_attributes [template::util::set_to_list $params id]

  template::adp_append_string \
    "\[template::element render \${form:id} $id { $tag_attributes } \]"
}

# Display the help information for an element

template_tag formhelp { params } {

  set id [template::get_attribute formwidget $params id]

  # get any additional HTML attributes specified by the designer
  set tag_attributes [template::util::set_to_list $params id]

  template::adp_append_string \
    "\[template::element render_help \${form:id} $id { $tag_attributes } \]"
}

# Report a form error if one is specified.

template_tag formerror { chunk params } {

  set id [template::get_attribute formwidget $params id]
  set type [ns_set get $params type]

  if {$type eq {}} {
    set key $id
  } else {
    set key $id:$type
  }

  template::adp_append_code "
    if \{ \[info exists formerror($key)\] \} \{
      set formerror($id) \$formerror($key)
    "

  if {$chunk eq {}} {

    template::adp_append_string "\$formerror($key)"

  } else {

    template::adp_compile_chunk $chunk
  }

  template::adp_append_code "\}"
}

# Render a group of form widgets

template_tag formgroup { chunk params } {

  set id [template::get_attribute formwidget $params id]

  # get any additional HTML attributes specified by the designer
  set tag_attributes [template::util::set_to_list $params id]

  # generate a list of options and option labels as a data source

  template::adp_append_code \
    "template::element options \${form:id} $id { $tag_attributes }"

  # make sure name is a parameter to pass to the rendering tag handler
  ns_set update $params name formgroup
  ns_set update $params id formgroup

  # Use the multiple or grid tag to render the form group depending on 
  # whether the cols attribute was specified
  
  if { [ns_set find $params cols] == -1 } {
    template_tag_multiple $chunk $params
  } else {
    template_tag_grid $chunk $params
  }
}

# render one element from a formgroup
template_tag formgroup-widget { chunk params } {
    set id [template::get_attribute formgroup-widget $params id]

    set row [template::get_attribute formgroup-widget $params row]
    # get any additional HTML attributes specified by the designer
    set tag_attributes [template::util::set_to_list $params id row]

    # generate a list of options and option labels as a data source


    template::adp_append_code \
        "template::element options \${form:id} $id { $tag_attributes }"
    
  # make sure name is a parameter to pass to the rendering tag handler
  ns_set update $params name formgroup
  ns_set update $params id formgroup
    template::adp_append_code "append __adp_output \"\$\{formgroup:${row}(widget)\} \$\{formgroup:${row}(label)\}\""

}

# Render a form, incorporating any additional markup attributes
# specified in the template.  Set the magic variable "form:id"
# for elements to reference

template_tag formtemplate { chunk params } {

  set level [template::adp_level]

  set id [template::get_attribute formtemplate $params id]

  upvar #$level $id:properties form_properties

  template::adp_append_code "set form:id \"$id\""

  # Set optional attributes for the grid template
  template::adp_append_code "
    upvar 0 \"$id:properties\" form_properties"

  foreach varname {headers title cols} {

    set form_properties($varname) [ns_set iget $params $varname]

    template::adp_append_code "
      set form_properties($varname) \"$form_properties($varname)\"
    "
  }

  # get any additional HTML attributes specified by the designer
  set tag_attributes [template::util::set_to_list $params \
    id style method title cols headers]

  template::adp_append_string \
      "\[template::form render $id { $tag_attributes } \]"

  if {[string trim $chunk] eq {}} {

    # generate the form body dynamically if none specified.
    set style [ns_set iget $params style]
    template::adp_append_string "\[template::form generate $id $style\]"

  } else {

    # compile the static form layout specified in the template
    template::adp_compile_chunk $chunk
   
    # Render any hidden variables that have not been rendered yet
    template::adp_append_string \
    "\[template::form check_elements $id\]"
  }

  if { [info exists form_properties(fieldset)] } {
      template::adp_append_string "</fieldset>"
  }
  template::adp_append_string "</form>"
}


# @private tag_child
#
# Implements the <tt>child</tt> tag which renders a child item.
# See the Developer Guide for more information. <br>
# The child tag format is 
# <blockquote><tt>
# &lt;child tag=<i>tag</i> index=<i>n embed args</i>&gt;
# </blockquote>
#
# @param params  The ns_set id for extra HTML parameters

template_tag child { params } {
  publish::process_tag child $params
}

# @private tag_relation
#
# Implements the <tt>relation</tt> tag which renders a related item.
# See the Developer Guide for more information. <br>
# The relation tag format is 
# <blockquote><tt>
# &lt;relation tag=<i>tag</i> index=<i>n embed args</i>&gt;
# </tt></blockquote>
#
# @param params  The ns_set id for extra HTML parameters

template_tag relation { params } {
  publish::process_tag relation $params
}


# @private tag_content
#
# Implements the <tt>content</tt> tag which renders the content
# of the current item.
# See the Developer Guide for more information. <br>
# The content tag format is simply <tt>&lt;content&gt;</tt>. The
# <tt>embed</tt> and <tt>no_merge</tt> parameters are implicit to
# the tag.
#
# @param params  The ns_set id for extra HTML parameters

template_tag content { params } {

  # Get item id/revision_id
  set item_id [publish::get_main_item_id]
  set revision_id [publish::get_main_revision_id]

  # Concatenate all other keys into the extra arguments list
  set extra_args [publish::set_to_pairs $params]

  # Add code to flush the cache

  # Render the item, return the html
  set    command "publish::get_html_body \[publish::handle_item"
  append command " \$::content::item_id"
  append command " -html \{$extra_args\} -no_merge -embed"
  append command " -revision_id \[publish::get_main_revision_id\]\]"

  template::adp_append_code "append __adp_output \[$command\]" 
}

# Include another template in the current template, but make 
# some other chunk dependent on whether or not the included
# template returned something.
#
# This is useful if, say, you want to wrap the template with some HTML,
# for example, a frame in a portal, but if there's nothing to show,
# you don't want to show the frame either.
#
# @author Lars Pind (lars@collaboraid.net)

template_tag include-optional { chunk params } {

  set src [ns_set iget $params src]

  #Start developer support frame around subordinate template.
  if { [llength [info procs ::ds_enabled_p]] && [llength [info procs ::ds_adp_start_box]] } {
      ::ds_adp_start_box -stub "\[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]"
  }

  # pass additional arguments as key-value pairs

  set command "template::adp_parse"
  append command " \[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]"
  append command " \[list"

  for { set i 0 } { $i < [ns_set size $params] } { incr i } {
      set key [ns_set key $params $i]
      if {$key eq "src"} { 
          continue 
      }
      set value [ns_set value $params $i]
      append command " $key \"$value\"";	# is $value quoted sufficiently?
  }
  append command "\]"

  # __adp_include_optional_output is a list that operates like a stack
  # So first we execute the include template, and push the result onto this stack
  # Then, if the output contained anything but whitespace, we also output the 
  # chunk inside the include-optional tag.
  # Finally, we pop the output off of the __adp_include_optional_output stack.

  template::adp_append_code "if { \[catch { ad_try { lappend __adp_include_optional_output \[$command\] } ad_script_abort val { } } errmsg\] } {"
  template::adp_append_code "    global errorInfo"
  template::adp_append_code "    append __adp_output \"Error in include template \\\"\[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]\\\": \$errmsg\""
  template::adp_append_code "    ns_log Error \"Error in include template \\\"\[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]\\\": \$errmsg\n\$errorInfo\""
  template::adp_append_code "} else {"
  template::adp_append_code "if { !\[string equal \[string trim \[lindex \$__adp_include_optional_output end\]\] \"\"] } {"

  template::adp_compile_chunk $chunk

  template::adp_append_code "
    }
    template::util::lpop __adp_include_optional_output
  }
  "

  #End developer support frame around subordinate template.
  if { [llength [info procs ::ds_enabled_p]] && [llength [info procs ::ds_adp_end_box]] } {
      ::ds_adp_end_box -stub "\[template::util::url_to_file \"$src\" \"\$__adp_stub\"\]"
  }

}

# Insert the output from the include-optional tag
#
# @author Lars Pind (lars@collaboraid.net)

template_tag include-output { params } {

  template::adp_append_code "
    if { \[info exists __adp_include_optional_output\] } {
      append __adp_output \[lindex \$__adp_include_optional_output end\]
    }
  "
}

template_tag trn { chunk params } {
  # DRB: we have to do our own variable substitution as the template framework doesn't handle
  # it for us ... being able to use page variables here is consistent with the rest
  # of the templating engine.

  # LARS: Note that this version of the <TRN> tag requires a body, like this:
  # <trn key="...">default</trn>.
  # This is the way to give a default value, and is okay, because we now have the #...# 
  # notation for when there's no default value.
  # Will register the key in the message catalog if it doesn't exist.

  set size [ns_set size $params] 
  for { set i 0 } { $i < $size } { incr i } {
     set [ns_set key $params $i] [ns_set value $params $i]
     # substitute array variables
     regsub {@([a-zA-Z0-9_]+)\.([a-zA-Z0-9_.]+)@} [set [ns_set key $params $i]] {${\1(\2)}} [ns_set key $params $i]
     # substitute regular variables
     regsub {@([a-zA-Z0-9_:]+)@} [set [ns_set key $params $i]] {${\1}} [ns_set key $params $i]
  }

  # And this needs to be executed at page execution time due to interactions with the
  # preferences changing code.  This is consistent with what the way #notation# is handled
  # (the ad_conn call is dumped into the code, not executed on the spot)

  if { ![info exists locale] } {
      # We need this to be executed at template execution time, because the template's
      # compiled code will be cached and reused for many requests.
      set locale "\[ad_conn locale\]"
  } else {
      # Check to see if we should register this into the message catalog
      if { [string length $locale] == 2 } {
          set locale [lang::util::default_locale_from_lang $locale]
      }

      # Check the cache
      if { ![lang::message::message_exists_p $locale $key] } {
          lang::message::register $locale $key $chunk
      }
  } 

  # quote dollar signs, square bracket and quotes
  regsub -all {[\]\[""\\$]} $chunk {\\&} quoted_chunk

  template::adp_append_code "append __adp_output \[_ $locale $key $quoted_chunk\]"
}


# DanW: implements a switch statement just like in tcl
# use as follows:
#
# <switch flag=regexp @some_var@>
#     <case in "foo" "bar" "baz">
#         Foo, Bar or Baz was selected
#     </case>
#     <case value="a.+">
#         A was selected
#     </case>
#     <case value="b.+">
#         B was selected
#     </case>
#     <case value="c.+">
#         C was selected
#     </case>
#     <default>
#         Not a valid selection
#     </default>
# </switch>
#
# The flag switch is optional and it defaults to exact if not specified.
# Valid values are exact, regexp, and glob

template_tag switch { chunk params } {

    set sw ""
    set arg ""
    set size [ns_set size $params]

    # get the switch flags and the switch var

    for { set i 0 } { $i < $size } { incr i } {
        set key [ns_set key $params $i]
        set value [ns_set value $params $i]

        if {$key eq $value} {
            set arg $key
        } elseif {$key eq "flag"} {
            append sw " -$value "            
        }
    }

    # append the switch statement and eval tags in between

    template::adp_append_code "switch $sw -- $arg {"

    template::adp_compile_chunk $chunk

    template::adp_append_code "}"
}


# case statements as part of switch statement as shown above
# 

template_tag case { chunk params } {

    # Scan the parameter stack backward, looking for the tag name

    set tag_id [template::enclosing_tag switch]
    if {$tag_id eq {}} {
        error "No enclosing SWITCH tag for CASE tag on value $value"
    }    

    # get the case value

    set value [ns_set iget $params value]

    # insert the case statement and eval the chunk in between

    if { $value ne "" } {

        # processing <case value= ...> form

        template::adp_append_code "[list $value] {" -nobreak        

        template::adp_compile_chunk $chunk

        template::adp_append_code "}"

    } else {

        # processing <case in ...> form

        set switches ""
        set size [ns_set size $params]
        set size_1 [expr {$size - 1}]

        for { set i 0 } { $i < $size } { incr i } {

            set key [ns_set key $params $i]
            set value [ns_set value $params $i]

            # pass over the first arg (syntax sugar), but check format
            if { $i == 0 } {

                if {$key ne "in" } {
                    error "Format error: should be <case in \"foo\" \"bar\" ...>"
                }

            } else {

                if {$key eq $value} {

                    # last item in list so process the chunk
                    if { $i == $size_1 } {

                        template::adp_append_code "$switches $value {" -nobreak
        
                        template::adp_compile_chunk $chunk

                        template::adp_append_code "}"

                    } else {

                        # previous items default to pass-through
                        append switches " $key - "
                    }
                    
                } else {
                    error "Format error: should be <case in \"foo\" \"bar\" ...>"
                }
            }
        }
    }
}

# default value for case statement which is a sub-tag in switch tag

template_tag default { chunk params } {

    # Scan the parameter stack backward, looking for the tag name

    set tag_id [template::enclosing_tag switch]
    if {$tag_id eq {}} {
        error "No enclosing SWITCH tag for DEFAULT tag"
    }    

    # insert the default value and evaluate the chunk

    template::adp_append_code "default {" -nobreak

    template::adp_compile_chunk $chunk

    template::adp_append_code "}"
}

# contract and comment tags for adding inline
# documentation to adp files.
#
# @author Ben Bytheway (ben@vrusp.com)

template_tag contract { chunk params } {}

template_tag comment { chunk params } {}
