path: root/Functions/MIME/zsh-mime-setup

emulate -L zsh
setopt extendedglob cbases

local opt o_verbose o_list

autoload -U zsh-mime-handler

while getopts "flv" opt; do
  case $opt in
    # List: show existing suffixes and their handlers then exit.
    (l)
    o_list=1
    ;;

    # Verbose; print diagnostics to stdout.
    (v)
    o_verbose=1
    ;;

    # Force; discard any existing settings before reading.
    (f)
    unset -m zsh_mime_\*
    ;;

    (*)
    [[ $opt = \? ]] || print -r "Option $opt not handled, complain" >&2
    return 1
    ;;
  esac
done
(( OPTIND > 1 )) && shift $(( OPTIND - 1 ))


if [[ -n $o_list ]]; then
  # List and return.
  for suffix in ${(ko)zsh_mime_handlers}; do
      print ${(r.10.)suffix}${zsh_mime_handlers[$suffix]}
      if [[ -n ${zsh_mime_flags[$suffix]} ]]; then
	print "  flags: ${zsh_mime_flags[$suffix]}"
      fi
  done
  return 0
fi


# Handler for each suffix.
(( ${+zsh_mime_handlers} )) || typeset -gA zsh_mime_handlers
# Corresponding flags, if any, for handler
(( ${+zsh_mime_flags} )) || typeset -gA zsh_mime_flags

# Internal maps read from MIME configuration files.
# Note we don't remember the types, just the mappings from suffixes
# to handlers and their flags.
typeset -A suffix_type_map type_handler_map type_flags_map

local -a type_files cap_files array match mbegin mend
local file line type suffix exts elt flags line2

# Customizable list of files to examine.
zstyle -a :mime: mime-types type_files ||
  type_files=(~/.mime.types /etc/mime.types)
zstyle -a :mime: mailcap cap_files ||
  cap_files=(~/.mailcap /etc/mailcap)

TRAPEXIT() { unfunction mime-setup-add-type >&/dev/null; return 0; }

mime-setup-add-type() {
    local type suffix
    local -a array

    type=$1
    shift

    while (( $# )); do
	# `.ps' instead of `ps' has been noted
	suffix=${1##.}
	shift

	if [[ -z $suffix_type_map[$suffix] ]]; then
	    [[ -n $o_verbose ]] && 
	    print -r "Adding type $type for $suffix" >&2
	    suffix_type_map[$suffix]=$type
	else
	    # Skip duplicates.
	    array=(${=suffix_type_map[$suffix]})
	    if [[ ${array[(I)$type]} -eq 0 ]]; then
		[[ -n $o_verbose ]] &&
		print -r "Appending type $type for already defined $suffix" >&2
		suffix_type_map[$suffix]+=" $type"
	    fi
	fi
    done
}

# Loop through files to find suffixes for MIME types.
# Earlier entries take precedence, so the files need to be listed
# with the user's own first.  This also means pre-existing
# values in suffix_type_map are respected.
for file in $type_files; do
    [[ -r $file ]] || continue

    # For once we rely on the fact that read handles continuation
    # lines ending in backslashes, i.e. there's no -r.
    while read line; do
	# Skip blank or comment lines.
	[[ $line = [[:space:]]#(\#*|) ]] && continue

	# There are two types of line you find in MIME type files.
	# The original simple sort contains the type name then suffixes
	# separated by whitespace.  However, Netscape insists
	# on adding lines with backslash continuation with
	# key="value" pairs.  So we'd better handle both.
	if [[ $line = *=* ]]; then
	    # Gory.
	    # This relies on the fact that a typical entry:
	    #   type=video/x-mpeg2 desc="MPEG2 Video" exts="mpv2,mp2v"
	    # looks like a parameter assignment.  However, we really
	    # don't want to be screwed up by future extensions,
	    # so we split the elements to an array and pick out the
	    # ones we're interested in.
	    type= exts=

	    # Syntactically split line to preserve quoted words.
	    array=(${(z)line})
	    for elt in $array; do
		if [[ $elt = (type|exts)=* ]]; then
		    eval $elt
		fi
	    done

	    # Get extensions by splitting on comma
	    array=(${(s.,.)exts})

	    [[ -n $type ]] && mime-setup-add-type $type $array
	else
	    # Simple.
	    mime-setup-add-type ${=line}
	fi
    done <$file
done


# Loop through files to find handlers for types.
for file in $cap_files; do
    [[ -r $file ]] || continue

    # Oh, great.  We need to preserve backslashes inside the line,
    # but need to manage continuation lines.
    while read -r line; do
	# Skip blank or comment lines.
	[[ $line = [[:space:]]#(\#*|) ]] && continue

	while [[ $line = (#b)(*)\\ ]]; do
	    line=$match[1]
	    read -r line2 || break
	    line+=$line2
	done

	# Guess what, this file has a completely different format.
	# See mailcap(4).
	# The biggest unpleasantness here is that the fields are
	# delimited by semicolons, but the command field, which
	# is the one we want to extract, may itself contain backslashed
	# semicolons.
	if [[ $line = (#b)[[:space:]]#([^[:space:]\;]##)[[:space:]]#\;(*) ]]
	then
	    # this is the only form we can handle, but there's no point
	    # issuing a warning for other forms.
	    type=$match[1]
            line=$match[2]
	    # See if it has flags after the command.
	    if [[ $line = (#b)(([^\;\\]|\\\;|\\[^\;])#)\;(*) ]]; then
		line=$match[1]
		flags=$match[3]
	    else
		flags=
	    fi
	    # Remove quotes from semicolons
	    line=${line//\\\;/\;}
	    # and remove any surrounding white space --- this might
	    # make the handler empty.
	    line=${${line##[[:space:]]#}%%[[:space:]]}
	    if [[ -z $type_handler_map[$type] ]]; then
		if [[ -n $o_verbose ]]; then
		    print -r "Adding handler for type $type:
  $line" >&2
		fi
		type_handler_map[$type]=$line
		type_flags_map[$type]=$flags
		if [[ -n $flags && -n $o_verbose ]]; then
		    print -r "  with flags $flags" >&2
		fi
	    elif [[ -n $o_verbose ]]; then
		print -r "Skipping handler for already defined type $type:
  $line" >&2
		if [[ -n $flags ]]; then
		    print -r " with flags $flags" >&2
		fi
	    fi
	fi
    done <$file
done


# Check for styles which override whatever is in the file.
# We need to make sure there is a handler set up; for some
# uses we may need to defer checking styles until zsh-mime-handler.
# How much we need to do here is a moot point.
zstyle -L | while read line; do
  array=(${(Q)${(z)line}})
  if [[ $array[3] = (handler|flags) && \
        $array[2] = (#b):mime:.([^:]##):(*) ]]; then
    suffix=$match[1]
    # Make sure there is a suffix alias set up for this.
    alias -s $suffix >&/dev/null || alias -s $suffix=zsh-mime-handler
  fi
done

# Now associate the suffixes directly with handlers.
# We just look for the first one with a handler.
# If there is no handler, we don't bother registering an alias
# for the suffix.

for suffix line in ${(kv)suffix_type_map}; do
  # Skip if we already have a handler.
  [[ -n $zsh_mime_handlers[$suffix] ]] && continue

  # Split the space-separated list of types.
  array=(${=line})

  # Find the first type with a handler.
  line2=
  for type in $array; do
    line2=${type_handler_map[$type]}
    [[ -n $line2 ]] && break
  done

  # See if there is a generic type/* handler.
  # TODO: do we need to consider other forms of wildcard?
  if [[ -z $line2 ]]; then
    for type in $array; do
      type="${type%%/*}/*"
      line2=${type_handler_map[$type]}
      [[ -n $line2 ]] && break
    done
  fi

  if [[ -n $line2 ]]; then
    # Found a type with a handler.
    # Install the zsh handler as an alias, but never override
    # existing suffix handling.
    alias -s $suffix >&/dev/null || alias -s $suffix=zsh-mime-handler

    zsh_mime_handlers[$suffix]=$line2
    zsh_mime_flags[$suffix]=$type_flags_map[$type]
  fi
done

true