#!/usr/bin/perl
# $Id$
$VERSION{'PUBLIC'} = '2.000';
$VERSION{''.__FILE__} = '$Revision$';
#
# >>Title::     SDF Tuning File Generator
#
# >>Copyright::
# Copyright (c) 1992-1997, Ian Clatworthy (ianc@mincom.com).
# You may distribute under the terms specified in the LICENSE file.
#
# >>History::
# -----------------------------------------------------------------------
# Date      Who     Change
# 18-Jan-97 ianc    SDF 2.000
# -----------------------------------------------------------------------
#
# >>Purpose::
# {{CMD:sdngen}} extracts SDF template information from a [[FrameMaker]]
# template.
#
# >>Description::
# !SDF_OPT_STD
#
# The -p option can be used to specify the root paragraph format from
# which others are derived. The default paragraph root is {{Body}}.
#
# The -f option can be used to specify the root font (i.e. phrase) format
# from which others are derived. The default font root is {{Emphasis}}.
#
# The -t option can be used to specify the root table format from
# which others are derived. The default table root is {{Format A}}.
#
# As formats often appear in families (e.g. Heading1, Heading2,
# etc.), {{sdngen}} will use the (alphabetically) previous format as
# the parent if it makes a better parent (i.e. there are less differences)
# than the default one.
#
# If a template already exists, it can be specified using the -e option.
# In this case, {{sdngen}} will get as much information as it can from
# that file including:
#
# * the root format for each type
# * the order of formats within a type
# * the parent for each format.
#
# Within each type, formats which are unknown in the existing template
# are output after those that are known.
#
# >>Examples::
# To generate an SDF tuning file file:
#
# V:     sdngen -osdn mytemplate.mif
#
# This will create a template file called {{FILE:mytemplate.sdn}}.
#
# >>Limitations::
#

require "sdf/app.pl";
require "sdf/parse.pl";
require "sdf/tomif.pl";

########## Initialisation ##########

# define configuration
%app_config = (
    'libdir',   'sdf/home',
);

# define options
push(@app_option, (
    #'Name|Spec|Help',
    'para_root|STR;Body|default parent for a paragraph format',
    'font_root|STR;Emphasis|default parent for a font format',
    'tbl_root|STR;Format A|default parent for a table format',
    'existing_template|STR|existing template file',
));

# handle options
&AppInit('file ...', 'generate an SDF template from a Frame one', 'SDF') ||
  &AppExit();

# initialise the lookup tables loaded when a template already exists
%objects = ();
%parents = ();

# if a template already exists, get as many details as we can from it
if ($existing_template ne '') {

    # Open the file
    unless(open(EXISTING, $existing_template)) {
        &AppExit("fatal", "unable to open existing template '$existing_template'");
    }

    # Scan the template for useful information
    while (<EXISTING>) {
        next unless /^\s*\!targetobject\s+/;
        ($type, $name, $parent) = split(/\s*\;\s*/, $');
        $type =~ s/^\s*["']//;
        $type =~ s/["']\s*$//;
        $name =~ s/^\s*["']//;
        $name =~ s/["']\s*$//;
        $parent =~ s/^\s*["']//;
        $parent =~ s/["']\s*$//;

        # Save the information
        $parents{$type,$name} = $parent;
        if ($objects{$type} eq '') {
            $objects{$type} = $name;
            $para_root = $name if $type eq 'Para';
            $font_root = $name if $type eq 'Phrase';
            $tbl_root  = $name if $type eq 'Table';
        }
        else {
            $objects{$type} .= "\000$name";
        }
    }
    close(EXISTING);
}


########## Support routines ##########

sub ConvertCatalogToSdf {
    local($type, $root, *catalog, *known_objects, *known_parents, *my_attr_list) = @_;
#   local();
    local(@names, @known_names, %known, @ordered_names);
    local(@attr_list);
    local(%root_attrs);
    local($name, $parent, %attrs, %parent_attrs);
    local($prev, %prev_attrs);
    local(%prev_diff, %root_diff, %this_diff);
    local($prev_diff_cnt, $root_diff_cnt);
    local($obj_cnt, $attr_cnt, $diff_cnt, $diff_avg);

    # Check that the catalog is not empty
    @names = sort keys %catalog;
    $obj_cnt = scalar(@names);
    unless ($obj_cnt) {
        &AppMsg("object", "NO $type formats found");
        return;
    }

    # Check that the root object exists
    if (!defined($catalog{$root})) {
        &AppMsg("warning", "root $type '$root' not found (using '$names[0]' instead)");
        $root = shift(@names);
    }

    # Get the attributes of the root object
    %root_attrs = &_MifAttrSplit($catalog{$root});

    # Output the root
    print "# Define the root '$type' format\n";
    &OutputTargetObject($type, $root, '', *root_attrs);

    # Decide on the attribute list to use
    @attr_list = @my_attr_list ? @my_attr_list : sort keys %root_attrs;

    # If there are known objects, output them first
    @known_names = split(/\000/, $known_objects{$type});
    if (@known_names) {
        %known = ();
        grep($known{$_}++, @known_names);
        @ordered_names = @known_names;
        for $name (@names) {
            push(@ordered_names, $name) unless $known{$name};
        }
    }
    else {
        @ordered_names = @names;
    }

    # Analyse and output the non-root formats
    print "\n# Define the other '$type' formats\n";
    %prev_attrs = ();
    $prev = '';
    $diff_cnt = 0;
    for $name (@ordered_names) {

        # Skip the root
        next if $name eq $root;

        # If the list includes names from an existing template,
        # the object might not exist in the catalog, so skip it
        next if $catalog{$name} eq '';

        # Get the attributes
        %attrs = &_MifAttrSplit($catalog{$name});

        # Get the parent and the attribute differences
        $parent = $known_parents{$type,$name};
        if ($parent ne '') {
            %parent_attrs = &_MifAttrSplit($catalog{$parent});
            %this_diff = &DiffAttrs(*attrs, *parent_attrs, *attr_list);
        }
        else {
            # Decide on the best parent
            %root_diff = &DiffAttrs(*attrs, *root_attrs, *attr_list);
            %prev_diff = &DiffAttrs(*attrs, *prev_attrs, *attr_list);
            $root_diff_cnt = scalar(keys %root_diff);
            $prev_diff_cnt = scalar(keys %prev_diff);
            if ($root_diff_cnt < $prev_diff_cnt) {
                $parent = $root;
                %this_diff = %root_diff;
            }
            else {
                $parent = $prev;
                %this_diff = %prev_diff;
            }
        }
        
        # Output the object
        &OutputTargetObject($type, $name, $parent, *this_diff);

        # Collect some stats
        $diff_cnt += scalar(keys %this_diff);
    }
    continue {
        # Save away the previous attributes and name
        %prev_attrs = %attrs;
        $prev = $name;
    }

    # Output some basic stats
    $attr_cnt = scalar(@attr_list);
    $diff_avg = sprintf("%.1f", $diff_cnt/($obj_cnt - 1));
    &AppMsg("object", "$obj_cnt $type formats, $attr_cnt attrs each," .
      " average difference is $diff_avg");
}

sub OutputTargetObject {
    local($type, $name, $parent, *attrs) = @_;
#   local();
    local($attr, $value);

    # Print the macro header
    $parent = " \"$parent\"" if $parent ne '';
    print "!targetobject \"$type\"; \"$name\";$parent";
    
    # Print the attributes, if any
    for $attr (sort keys %attrs) {
        $value = &FormatValue($attrs{$attr});
        print "; \\\n  $attr=$value";
    }
    print "\n\n";
}

sub FormatValue {
    local($value) = @_;
    local($result);

    # Integers and enumerated values are fine as is
    # Values with " are enclosed in '', otherwise
    # the value is enclosed in "".
    if ($value =~ /^\d+$/ || $value =~ /^[A-Z][a-z]+$/) {
        return $value;
    }
    elsif ($value =~ /["\\]/) {
        return "'$value'";
    }
    else {
        return '"' . $value . '"';
    }
}

sub DiffAttrs {
    local(*nv1, *nv2, *name_list) = @_;
    local(%diff);
    local($name);

    # Check the empty set first
    return %nv1 unless %nv2;

    # Find the differences
    %diff = ();
    for $name (@name_list) {
        $diff{$name} = $nv1{$name} unless $nv1{$name} eq $nv2{$name};
    }

    # Return result
    return %diff;
}

########## Processing ##########

sub argProcess {
    local($ARGV) = @_;
#   local();

    # Fetch the template
    unless (&_MifFetchTemplate($ARGV)) {
        &AppMsg("abort", "unable to fetch MIF template '$ARGV'");
        return;
    }

    # Convert the MIF catalogs into an SDF template
    &ConvertCatalogToSdf('Para',   $para_root, *_mif_tpl_paras, *objects,
      *parents, *MIF_PARA_ATTRS);
    &ConvertCatalogToSdf('Phrase', $font_root, *_mif_tpl_fonts, *objects,
      *parents, *MIF_FONT_ATTRS);
    &ConvertCatalogToSdf('Table',  $tbl_root,  *_mif_tpl_tbls, *objects,
      *parents);
}

&AppProcess('argProcess');
&AppExit();