=head1 NAME

Net::Hotline::Client - Perl library for the Hotline internet client

=head1 SYNOPSIS

    use Net::Hotline::Client;

    $hlc = new Net::Hotline::Client;
    $hlc->connect("127.0.0.1")

    $hlc->chat_handler(\&Chat_Handler);
    $hlc->msg_handler(\&Msg_Handler);

    $hlc->login(Login    => "Steve",
                Password => "xyzzy",
                Nickname => "Jobs",
                Icon     => 128);

    $hlc->run();
    ...

=head1 DESCRIPTION

Net::Hotline::Client is a class implementing a Hotline internet client in
Perl.  It was specifically developed to aid in the creation of Hotline
"bots," although it's suitable for most other tasks as well. Hotline is an
internet client/server system that's sort of a cross between IRC and a BBS.
See http://www.hotlinesw.com/ for more information.

This document assumes you have some knowledge of the Hotline client. If
not, I suggest downloading it from the URL above.  (It's shareware. Mac and
PC versions are available)

=head1 CAVEATS

The Hotline protocol is not public. (An RFC?  I wish!)  This module got its
start with the aid of the C source code from the Unix "hx" Hotline client
written by Ryan Nielsen, the beginnings of a Java Hotline bot written by Gary
Wong, and many hours spent staring at hexdumps of network data. Some features
are still not implemented, the most notable being user administration
capabilities.  Finally, I'm sure all hell will break loose with the next major
revision of Hotline.  Such is life.

=head1 GETTING STARTED

Before delving into the nitty-gritty details, it's important to understand
the philosophy behind design of this module.  If you do not read this
section first, you will probably be confused by the rest of the
documentation. Take the time now and save yourself headaches later.

Hotline is an event-driven protocol.  A Hotline client receives packets
each time something interesting occurs on the server--a new user joins,
someone says something in chat, someone goes idle, etc.  The client
receives these packets whether it's ready for them or not.  This type of
interaction lends itself to an event-loop/callback-routine design,
which is how this module was originally implemented.  Handler routines are
set for the events you're interested in, and then the event loop is started.

In this model, client actions are also treated as events.  To retrieve the
news, for example, the client calls a function that sends a news request to
the server and returns a task ID number.  The client then returns to the
event loop and watches the incoming packet stream for a packet with the
same task ID (it will be either a packet containing the news or a task
error packet).  In the time between when the news request was sent and the
response is received from the server, many other unrelated events can (and
probably will) occur.

This system works great for things like bots that want to deal with events
in a non-linear fashion, but what about when you want to do things in a
more deterministic manner?  For example, imagine trying to implement a
command line FTP-like Hotline client using the event loop model.  Sure,
it's possible, but it's not pretty!  I found this out the hard way.  What's
needed are what I'm going to call "blocking tasks."  That is, function
calls that don't return until their work is done.  In this new model, the
news request function would not merely return a task ID number, it would
return the news itself (or an error, of course).

To accomplish this, the "blocking task" version of the news retrieval
function has to do everything that you'd do in the event loop model: send a
request for the news and watch the incoming packet stream for the task
results.  There's no magic here.  Of course, the question of what to do
with those "unrelated" packets presents itself.  They can't just be ignored
because they may be telling the client something important like "you've
just been disconnected."  On the other hand, allowing them to invoke
handler routines might spin us off into another section of the code
indefinitely.

The solution I came up with is to let the user decide.  All unrelated
events that occur during blocking tasks are subject to the bare minimum
processing needed to keep the internal state of the client object
consistent (tracking joining and leaving users, disconnect messages, etc.).
Going further, handler routines can indeed be called.  The behavior is
controlled by the client object's attributes.

These two modes of operation are called "event loop mode" and "blocking
task mode" in the rest of the documentation. It's important to decide which
model suits your particular needs before starting your Hotline client code.
Blindly mixing and matching these techniques will get you nowhere fast.
Now, on to the good stuff...

=head1 METHODS

=head2 CONNECTING

=over 4

=item connect ADDRESS

Opens a network connection to ADDRESS, which can be an IP address or
hostname optionally followed by a space or a colon and a port number. If no
port is given, it defaults to 5500 (Hotline standard port)

Examples:

    $hlc->connect("127.0.0.1:1234");
    $hlc->connect("hostname.com 5678");

Returns 1 if successful, undef otherwise.

=item disconnect

Closes the network connection.  Returns 1 if a connection was closed, undef
if the connection wasn't open to begin with.

=item login PARAMETERS

Logs into a Hotline server opened via C<connect()>, and requests the news
and the userlist (unless overridden by the "NoNews" and "NoUserList"
parameters).  Arguments are in a "named parameter" format, and are
case-sensitive.  The parameters are:

    Nickname    Your nickname (default: guest)
    Login       Your account name (default: guest)
    Password    Your account password (default: <none>)
    Icon        Your icon number (default: 410, the big red "H")
    NoNews      If true, do not request the news.
    NoUserList  If true, do not request the userlist.

Example of use:

    $hlc->login(Login    => "Steve",
                Password => "xyzzy",
                Nickname => "Jobs",
                Icon     => 128,
                NoNews   => 1);

If omitted, all parameters except Password will default to some sane (if
not necessarily "sensible") value.  The news and userlist will be requested
unless NoNews and/or NoUserList are explicitly set by the user.  Keep in
mind that client functions like the tracking of connected users will not
work properly without the userlist.

In blocking task mode, login() returns 1 on success, undef if an error
occurred, and "zero but true" ("0E-0") if the login was successful, but the
news and/or userlist retrieval failed.

In event loop mode, login() returns the task number if the login request was
sent successfully, undef otherwise.

=item run

Starts the event loop.  Returns when the connection has to the server has
been closed.

=back

=head2 SETTINGS

=over 4

=item blocking EXPR

Turns blocking network i/o on or off depending on how EXPR evaluates (true
turns blocking i/o on).  Returns the current setting.  Blocking i/o is on by
default.  In this mode, the event loop will cycle each time data of any
kind comes from the server.  This means that your hotline client may spend
a lot of its time blocked (and therefore unable to do anything interesting)
waiting for something to happen on the server.  Using non-blocking i/o will
cycle through the event loop more frequently (see C<event_timing()> below)
regardless of server activity.

=item blocking_tasks EXPR

With no arguments, returns the blocking task status.  With one argument,
blocking tasks will be turned on or off depending on how EXPR evaluates
(true means blocking task mode is active).  Blocking tasks are off by
default.

=item clear_error

Clears the error message text available via C<last_error()>. 
C<last_error()> is not cleared by the client object, so you may need to
explicitly clear it before running a blocking task to prevent it from
containing an old, unrelated error message if the blocking task somehow
failed without setting C<last_error()>.  (This should not happen, but
you never know...)

=item connect_timeout SECS

Sets the connection timeout to SECS seconds (if present).  Returns
the current connection timeout.

=item data_fork_extension TEXT

Sets the data fork filename extension for downloads to TEXT (if present).
Returns the current data fork filename extension.  The default setting
is ".data"

=item downloads_dir PATH

Sets the directory where downloaded files are placed to PATH (if present).
Returns the current setting.

=item event_timing SECS

Sets the event loop timing to SECS seconds (if present).  Fractional
seconds are allowed. The default setting is 1 second.  This option only has
an effect when non-blocking i/o is active (see C<blocking()>).  Returns the
current event timing setting.

=item handlers_during_blocking_tasks EXPR

Allows handlers to run during blocking tasks if EXPR is present and
evaluates to true.  Returns the current setting.  The default setting is
off.

=item path_separator CHARACTER

Sets the path separator to CHARACTER (if present).  The default setting is
the Mac OS path separator ":".  Returns the current value of the path
separator.  Note that this is the path separator used when sending commands
to the server and has no bearing on what the path separator is on the local
system.  You should not need to change this, since all current Hotline
servers use ":" regardless of the platform they're running on.

=item rsrc_fork_extension TEXT

Sets the resource fork filename extension for downloads to TEXT (if
present). Returns the current resource fork filename extension.  The
default setting is ".rsrc"

=item tracker ADDR

Sets the tracker address to ADDR (if present), where ADDR is an IP address
or hostname, optionally followed by a colon and a port number.  Returns the
current tracker address.

=item xfer_bufsize BYTES

Sets the file transfer buffer size to BYTES.  Returns the current buffer
size.  The default is 4096 bytes.

=back

=head2 COMMANDS

Unless otherwise specified, the methods in this section are treated as "tasks"
by Hotline. Their status (start time, finish time, error state, etc.) is
tracked internally by task number.  In event mode, they return a task number
if the request was sent successfully, and undef or an empty list if an error
occurred.  In blocking task mode, the return values vary.

Some commands (like C<chat()> and C<pchat()>, for example) are not treated as
"tasks" by Hotline. They always return 1 on success, rather than a task
number.  The actual completion of a such commands can only be determined by
examining the resulting data from the server.  For example, if you
C<chat("hello")>, you can look for that line of chat in your chat handler.
(This is rarely necessary since the failure of such a command usually means
that you have much bigger problems.)

=over 4

=item ban USER

=item ban SOCKET

Bans the user specified by a Net::Hotline::User object or a user socket
number.

In blocking task mode, returns 1 on success or undef if an error occurred.
In event loop mode, returns a task number if the request was sent
successfully, or undef if an error occurred.

=item chat LIST

Sends the text formed by the concatenation of LIST to the server as "chat."
Perl newlines ("\n") are translated to Net::Hotline::Constants::HTLC_NEWLINE,
which is Hotline's native newline character.

Not treated as a task: returns 1 on success, undef or an empty list on failure.

=item chat_action LIST

Sends the text formed by the concatenation of LIST to the server as a "chat
action."  Perl newlines ("\n") are translated to
Net::Hotline::Constants::HTLC_NEWLINE, which is Hotline's native newline
character.

Not treated as a task: returns 1 on success, undef or an empty list on failure.

=item comment PATH, TEXT

Sets the comments for the file or folder located at PATH to TEXT. If TEXT
is undef or an empty string, the comments for the file or folder will be
removed.

In blocking task mode, returns 1 on success or undef if an error occurred.
In event loop mode, returns a task number if the request was sent
successfully, or undef if an error occurred.

=item delete_file PATH

Deletes the file or folder located at located at PATH.

In blocking task mode, returns 1 on success or undef if an error occurred.
In event loop mode, returns a task number if the request was sent
successfully, or undef if an error occurred.

=item get_file PATH

Download the file on the server located at PATH to the local directory
set via C<downloads_dir()>.  In Mac OS, file names longer than 31
characters are truncated, preserving the filename extension (i.e. ".jpg")
if possible.

In blocking task mode, returns either an array (in array context) or a
reference to an array (in scalar context) containing a Net::Hotline::Task
object, a download reference number, and the size of the download on
success, an undef or an empty list if an error occurred.  Those return
values are meant to be fed to C<recv_file()> like this (error handling
omitted):

	($task, $ref, $size) = $hlc->get_file("Folder1:file.sit");

	$hlc->recv_file($task, $ref, $size);

In event loop mode, returns a task number if the request was sent
successfully, and undef or an empty list if an error occurred.

=item get_file_resume PATH

Resume downloading the file on the server located at PATH to the local
directory set via C<downloads_dir()>.  The partially downloaded file(s)
must exist in the local download directory, and (on non-Mac OS systems)
must have filename extensions matching the current settings of
C<data_fork_extension()> and C<rsrc_fork_extensions()>.

In blocking task mode, returns either an array (in array context) or a
reference to an array (in scalar context) containing a Net::Hotline::Task
object, a download reference number, and the size of the download on
success, and undef or an empty list if an error occurred.  Those return
values are meant to be fed to C<recv_file()> like this (error handling
omitted):

	($task, $ref, $size) = $hlc->get_file_resume("Folder1:file.sit");

	$hlc->recv_file($task, $ref, $size);

In event loop mode, returns a task number if the request was sent
successfully, and undef or an empty list if an error occurred.

=item get_fileinfo PATH

Returns a Net::Hotline::FileInfoItem object corresponding to the file
specified by PATH, or undef if an error occurred. Should only be used in
blocking task mode.

=item get_filelist PATH

Returns an array (in array context) or a reference to an array (in scalar
context) of Net::Hotline::FileListItem objects corresponding to the
contents of the server directory PATH, and the scalar value 0 if an error
occurred (in order to distinguish between an empty directory and an error:
an empty directory will return an empty list in array context and undef in
scalar context). Should only be used in blocking task mode.

=item get_news

Get the news from the server.

Returns an array containing the new posts (in array context) or the news as
a string (in scalar context) on success, and undef if an error occurred.
Note that successful retrieval of an empty news file will return an empty
string ("") or an empty list. Should only be used in blocking task mode.

=item get_userinfo SOCKET

Returns information about the user specified by SOCKET as a string, or
undef if there was an error.  Will not work unless the userlist has been
retrieved from the server.  Should only be used in blocking task mode.

=item get_userlist

Returns a reference to a hash keyed by socket number containing
Net::Hotline::User objects for all users currently logged on. Should only
be used in blocking task mode.

=item icon ICON

Sets your icon in the userlist to ICON, where ICON is an icon ID number.

=item kick USER

=item kick SOCKET

Disconnects the user specified by a Net::Hotline::User object or a user
socket number.

In blocking task mode, returns 1 on success or undef if an error occurred.
In event loop mode, returns a task number if the request was sent
successfully, or undef if an error occurred.

=item macbinary MACBIN_FILE, DATA_FILE, DATA_LEN, RSRC_FILE, RSRC_LEN BUF_SIZE, TYPE, CREATOR, COMMENTS, CREATED, MODIFIED, FINDER_FLAGS

Creates a MacBinary II file at the path designated by MACBIN_FILE based on
the file paths and other information supplied as arguments (see the
C<recv_file()> method for a description of the other arguments).  If
MACBIN_FILE is undefined, it defaults to DATA_FILE with ".bin" tacked onto
the end.  It returns 1 on success, and undef if MACBIN_FILE already exists
or can't be created, if DATA_LEN is greater than zero and DATA_FILE can't
be opened, or if RSRC_LEN is greater than zero and RSRC_FILE can't be
opened.  The error condition is available via both C<last_error()> and
$! because macbinary() can be called as a method or as a function.  Example:

    # As a method
    unless($hlc->macbinary(@args))
    {
      die "macbinary: ", $hlc->last_error();
    }

    # As a function
    unless(macbinary(@args))
    {
      die "macbinary: $!";
    }

=item move SRC, DEST

Moves the file or folder located at the path SRC to the directory located
at the path DEST.  SRC should be the full path to the file or folder you
want to move, and DEST should be the full path to the B<directory> you want
to move SRC too.  The file or folder name should only appear in the SRC
path, never in the DEST path.  As a consequence, renaming files or folders
must be done through C<rename()> and cannot be rolled into a C<move()> call. 
Here's an example of a valid call to C<move()>:

    $hlc->move("Folder1:file1", "Folder2:");

This moves the "file1" from "Folder1" to "Folder2"

In blocking task mode, returns 1 on success or undef if an error occurred.
In event loop mode, returns a task number if the request was sent
successfully, or undef if an error occurred.

=item msg USER, LIST

=item msg SOCKET, LIST

Sends the text formed by the concatenation of LIST as a private message to
the user specified by a Net::Hotline::User object or a user socket number.

In blocking task mode, returns 1 on success or undef if an error occurred.
In event loop mode, returns a task number if the request was sent
successfully, or undef if an error occurred.

=item new_folder PATH

Create a new folder located at PATH.

In blocking task mode, returns 1 on success or undef if an error occurred.
In event loop mode, returns a task number if the request was sent
successfully, or undef if an error occurred.

=item nick TEXT

Sets your nickname in the userlist to TEXT.

=item pchat REF, LIST

Sends the text formed by the concatenation of LIST to the private chat window
specified by REF.  Perl newlines ("\n") are translated to
Net::Hotline::Constants::HTLC_NEWLINE, which is Hotline's native newline
character.

Not treated as a task: returns 1 on success, undef or an empty list on failure.

=item pchat_action REF, LIST

Sends the text formed by the concatenation of LIST to the private chat window
specified by REF as a "chat action".  Perl newlines ("\n") are translated to
Net::Hotline::Constants::HTLC_NEWLINE, which is Hotline's native newline
character.

Not treated as a task: returns 1 on success, undef or an empty list on failure.

=item pchat_accept REF

Accepts an invitaton to the private chat sepcified by REF.

In blocking task mode, returns 1 on success.  In event loop mode, returns a
task number if the request was sent successfully.  In both modes, it returns
undef or an empty list if an error occurred.

=item pchat_decline REF

Declines an invitaton to the private chat sepcified by REF.

Not treated as a task: returns 1 on success, undef or an empty list on failure.

=item pchat_invite SOCKET, REF

Invite the user specified by SOCKET to an existing private chat specfied by
REF, or create a new private chat if REF is not given.  There is no
C<pchat_create()> command.  To create a new private chat, you must invite
someone.  Call C<pchat_invite()> with your own socket number and no REF
argument to create a new private chat with only yourself in it (you will 
not have to explicitly accept this invitation).

In blocking task mode, returns 1 on success, and undef or an empty list
if an error occurred.

In event mode, it returns a task number if it had to create a new private chat
(i.e. if no REF argument was given) or 1 (if inviting to an existing private
chat) on success, and undef or an empty list if an error occurred.

=item pchat_leave REF

Leave the private chat specified by REF.

Not treated as a task: returns 1 on success, undef or an empty list on failure.

=item pchat_subject REF, TEXT

Sets the subject of the private chat specified by REF to TEXT.

Not treated as a task: returns 1 on success, undef or an empty list on failure.

=item post_news LIST

Sends the text formed by the concatenation of LIST to the server as a
news post.

In blocking task mode, returns 1 on success.  In event loop mode, returns a
task number if the request was sent successfully.  In both modes, it returns
undef or an empty list if an error occurred.

=item put_file SRC_PATH, DEST_PATH, COMMENT

Upload the file located at SRC_PATH to the server directory DEST_PATH, with
the file comments COMMENT.  SRC_PATH must be in the native path format of
the local system (i.e. using ":" as the path separator on Mac OS, and "/"
on most other OSes).  DEST_PATH must be in Hotline's native path format
(":" as the path separator). If COMMENT is omitted, the actual Finder
comments will be read from the file to be uploaded if running on Mac OS. 
Otherwise, the comments will be blank.  C<put_file()> tries to upload a new
file. If you are resuming a file upload, you must call
C<send_file_resume()> instead.

In blocking task mode, returns an array (in array context) or a reference
to an array (in scalar context) containing a Net::Hotline::Task object, an
upload reference number, and the size of the upload, and undef or an empty
list if an error occurred.  Those return values are meant to be fed to
C<send_file()> like this (error handling omitted):

	($task, $ref, $size) = $hlc->put_file("/home/john/file.gz",
	                                      "Folder1:Folder2"
	                                      "A fun file!");

	$hlc->send_file($task, $ref, $size);

In event loop mode, returns a task number if the request was sent
successfully, and undef or an empty list if an error occurred.

=item put_file_resume SRC_PATH, DEST_PATH, COMMENT

Resume uploading the file located at SRC_PATH to the server directory
DEST_PATH, with the file comments COMMENT.  SRC_PATH must be in the native
path format of the local system (i.e. using ":" as the path separator on
Mac OS, and "/" on most other OSes).  DEST_PATH must be in Hotline's native
path format (":" as the path separator). If COMMENT is omitted, the actual
Finder comments will be read from the file to be uploaded if running on Mac
OS. Otherwise, the comments will be blank.  Use C<put_file()> to upload a
new file.

In blocking task mode, returns an array (in array context) or a reference
to an array (in scalar context) containing a Net::Hotline::Task object, an
upload reference number, the size of the upload, and additional information
needed to resume the upload, and undef or an empty list if an error
occurred. Those return values are meant to be fed to C<send_file()> like
this (error handling omitted):

	($task, $ref, $size, $rflt) = 
	  $hlc->put_file_resume("/home/john/file.gz",
	                        "Folder1:Folder2"
	                        "A fun file!");

	$hlc->send_file($task, $ref, $size, $rflt);

In event loop mode, returns a task number if the request was sent
successfully, and undef or an empty list if an error occurred.

=item recv_file TASK, REF, SIZE

Starts receiving the file designated by the Net::Hotline::Task object TASK,
the download reference number REF, and the size in bytes SIZE returned by
C<get_file()> (in blocking task mode) or supplied to the C<get_file()>
handler routine (in event loop mode).  When the download is complete,
C<recv_file()> returns  a reference to an array containing the following
values:

    DATA_FILE      Path to the file containing the data fork.
    DATA_LEN       Length of the data fork.
    RSRC_FILE      Path to the file containing the Mac resource fork.
    RSRC_LEN       Length of the resource fork.
    BUFSIZE        Buffer size that was used during the download.
    TYPE           Four-letter Mac file type code.
    CREATOR        Four-letter Mac file creator code.
    COMMENTS       Mac Finder comments.
    CREATED        Date created (in Mac time format)
    MODIFIED       Date modified (in Mac time format)
    FINDER_FLAGS   Mac finder flags packed in two bytes.

which are typically fed to the C<macbinary()> method to create a single
MacBinary II file from the separate resource fork and data fork files. (On
Mac OS systems, a single Mac OS-native two-forked file is created, so
there's no need to call C<macbinary()>)  Here's an example of typical usage
(error checking omitted):

    # Event loop mode:
    # (Inside your get_file() handler subroutine)
    ...
    $ret = $hlc->recv_file($task, $ref, $size);
    $hlc->macbinary(undef, $ret);
    ...

or

    # Blocking task mode:
    ...
    ($task, $ref, $size) = $hlc->get_file($path);
    $ret = $hlc->recv_file($task, $ref, $size);
    $hlc->macbinary(undef, $ret)
    ...

See C<macbinary()> for more details on its usage.  If either the data fork
or resource fork is empty, the fork length returned by C<recv_file()> will
be zero and the file path returned will be undef.

=item rename PATH, NAME

Renames the file or folder located at PATH to NAME.  Note that PATH
is the full path to the target, but NAME is just the new name without
any path specification.  Example:

    $hlc->rename("Pets:cat", "dog");

This changes the name of the file "cat" in the folder "Pets" to "dog"

In blocking task mode, returns 1 on success or undef if an error occurred.
In event loop mode, returns a task number if the request was sent
successfully, or undef if an error occurred.

=item send_file TASK, REF, SIZE, RFLT

Starts sending the file designated by the Net::Hotline::Task object TASK,
the upload reference number REF, the size in bytes SIZE, and the resume
information RFLT returned by C<put_file()> (in blocking task mode) or
supplied to the C<put_file()> handler routine (in event loop mode). Returns
1 if the upload completed successfully, or undef if there was an error.

=item tracker_list TIMEOUT

Connects to the server set via the C<tracker()> method and retrieves the
list of servers tracked by that tracker.  Returns an array (in array
context) or a reference to an array (in scalar context) of
Net::Hotline::TrackerListItem objects on success, and undef or an empty
list on failure, with the error condition available via C<last_error()>.

The initial connection to the tracker will timeout after TIMEOUT seconds,
or the current value set via C<connection_timeout()> if TIMEOUT is omitted.
A TIMEOUT value of zero will disable the timeout.

Note that this method does not return until it has retrieved the list of
tracked servers, and that the timeout applies B<only> to the initial
connection to the tracker.  It is often the case with overloaded trackers
that this method will hang when writing to or reading from the tracker
(regardless of the timeout value), many times resulting in a C<die> with a
broken pipe error in one of the network I/O functions.  To avoid this,
either try a more responsive tracker and/or wrap your C<tracker_list()>
call in an C<eval> block and check C<$@>.

=back

=head2 REQUESTS

All the methods in this section are treated as "tasks" by Hotline. Their
status (start time, finish time, error state, etc.) is tracked internally
by task number.  They return a task number if the request was sent
successfully, undef otherwise.

When a tasks completes, the data is stored in the appropriate
Net::Hotline::Client attribute.  For example, when a C<req_news()> task
completes, the data is available via the news() method.

=over 4

=item req_filelist PATH

Requests the file listing for the folder specified by PATH, or the root
directory if PATH is omitted.

=item req_fileinfo PATH

Requests the file information for the file or folder specified by PATH.

=item req_news

Requests the news from the server.

=item req_userinfo SOCKET

Requests user information for the user specified by SOCKET.

=item req_userlist

Request the list of users currently logged on.

=back

=head2 ATTRIBUTES

The methods in this section return data or references to data structures
in the Net::Hotline::Client object.  Some data structures contain references to
objects.  For details on those objects, see their respective documentation
(i.e. perldoc Net::Hotline::User)

=over 4

=item agreement

Returns a reference to the server's user agreement text, or undef if there
is none.

=item connected

Returns true if a network connection to a server is open.

=item files

Returns a reference to a hash of arrays containing Net::Hotline::FileListItem
objects, keyed by directory path.  Here's some sample code that prints the
entire file tree:

    $files = $hlc->files();              # Get reference to the file tree

    foreach $directory (keys(%{$files}))
    {
      print "$directory\n";              # Ex: "Uploads:Pictures"

      foreach $file (@{$files->{$directory}})
      {
        print "\t", $file->name(), "\n"; # Ex: "Picture.jpg"
      }
    }

=item last_activity

Returns the time the last packet was received from the server in the
system's native C<time()> format. (Usually seconds since the Unix epoch.
MacPerl is probably the only odd-ball)

=item last_error

Returns a text error message detailing the last error that occurred.  Use this
method to determine the cause of failure when a blocking task returns undef.
Example:

	...
	$hlc->blocking_tasks(1);
	...
	$hlc->get_filelist("Folder1") || die $hlc->last_error();

Don't rely on C<last_error()> unless you're in blocking task mode.  In
event loop mode, set a handler routine via C<task_error_handler()> and deal
with errors there via the task object's C<error()> and C<error_text()>
methods.

=item logged_in

Returns true if currently logged into a server.

=item news

Returns a reference to an array of news posts, or undef if the news has not
yet been requested or is empty.

=item pchats

Returns a reference to a hash of Net::Hotline::PrivateChat objects, keyed by
reference number, that represent all the private chats that the client is
currently engaged in, or undef or an empty list if not in any private chats.

=item server

Returns the address of the server currently connected to as a hostname or
IP address, depending on what the actual argument to C<connect()> was.  If
the port connected to is anything other than the standard Hotline port
(5500), then a colon and the port number are tacked onto the end of the
server name.  If not connected at all, undef is returned.

=item userlist

Returns a reference to a hash of Net::Hotline::User objects keyed by socket
number, or undef if the userlist has not yet been received.

=item user_by_nick REGEX

Returns reference(s) to user objects with nicknames matching REGEX, and
undef or an empty list if there are no matches.  Also returns undef or an
empty list if called before the userlist has been retrieved from the
server. REGEX is treated as a case-sensitive anchored regular expression
internally (i.e. C</^REGEX$/>). If your regex matches more than one user's
nickname, and C<user_by_nick()> was called in array context, an array of
references to user objects will be returned. Otherwise, the first user
object that matched will be returned (as ordered by socket number, from low
to high).

=item user_by_socket SOCKET

Returns the user object whose socket number is equal to SOCKET, or undef if
there is no user at that socket.

=back

=head2 HANDLERS

The methods in this section deal with getting and setting the handler
routines for events and tasks.  If you do not set your own handler for an
event, the default handler (usually just a print to STDOUT) will be used.
You can enable and disable the default handlers with the
C<default_handlers()> method.  They are disabled by default.

=over 4

=item default_handlers EXPR

If EXPR is omitted, it returns the default handler setting.  Otherwise, it 
sets the default handler setting to EXPR (anything that evaluates to true 
is considered "on").  Default handlers are disabled by default.

=item handlers

Returns a reference to a hash, keyed by event type strings (the strings in
CAPS below).  The values associated with the keys are either code
references or undef.  Event types are as follows:

    Events:

    AGREEMENT      User agreement text received.
    CHAT           New chat appeared.
    CHAT_ACTION    A new chat "action" appeared.
    COLOR          A user changed color in the userlist.
    EVENT          Next cycle in the event loop.
    ICON           A user changed icon in the userlist.
    JOIN           A user joined the server.
    LEAVE          A user left the server.
    MSG            A private message arrived.
    NEWS           News received.
    NEWS_POSTED    A news post was made by another user.
    NICK           A user changed nickname in the userlist.
    PCHAT_CHAT     New private chat appeared.
    PCHAT_ACTION   A new private chat action appeared.
    PCHAT_INVITE   An invitation to private chat arrived.
    PCHAT_JOIN     A user joined a private chat.
    PCHAT_LEAVE    A user left a private chat.
    PCHAT_SUBJECT  Private chat subject changed.
    QUIT           The server was shutdown politely.
    SERVER_MSG     A server message arrived.

    Tasks:

    BAN            Ban user task completed.
    FILE_DELETE    A file or folder was deleted.
    FILE_GET       A file download is ready to begin.
    FILE_PUT       A file upload is ready to begin.
    FILE_GET_INFO  File information received.
    FILE_SET_INFO  File information set.
    FILE_LIST      File list received.
    FILE_MKDIR     New folder created.
    FILE_MOVE      A file or folder was moved.
    KICK           Disconnect user task completed.
    LOGIN          Login task completed.
    NEWS_POST      News post task completed.
    PCHAT_ACCEPT   You have joined a private chat.
    PCHAT_CREATE   New private chat created.
    SEND_MSG       Private message sent.
    TASK_ERROR     A task error ocurred.
    USER_GETINFO   User information received.
    USER_LIST      User list received.

=back

=head2 SET/GET HANDLERS

The methods in this section expect either one code reference argument, or no
arguments at all.  With one argument, the handler is set to the given code
reference.  The return value is always the current value of the handler
(should be either undef or a code reference).

The code reference should point to a subroutine that expects at least one
argument: the Net::Hotline::Client object itself (listed as "SELF" below). 
Other arguments vary according to the event being handled. In this section,
only the varying arguments to the handler subroutine are described.

Also note that you don't have to do the "obvious" tasks associated with
each handler.  For example, in the "leave" handler, you don't have to
remove the user from the userlist.  That will be done for you by the
Net::Hotline::Client object.

=head3 EVENTS

=over 4

=item agreement_handler CODE (SELF, TEXT)

User agreement text received.

    TEXT        Reference to the agreement text.

=item chat_handler CODE (SELF, TEXT)

New chat appeared.

    TEXT        Reference to the chat text.

=item chat_action_handler CODE (SELF, TEXT)

A new chat "action" appeared.

    TEXT        Reference to the chat action text.

=item color_handler CODE (SELF, USER, OLD_COLOR, NEW_COLOR)

A user changed color in the userlist.

    USER        A Net::Hotline::User object.
    OLD_COLOR   The user's previous color.
    NEW_COLOR   The user's new color.

Valid colors:

    1    Black  Active normal user.  
    2    Red    Active admin user.
    3    Gray   Inactive normal user.
    4    Pink   Inactive admin user.

The hash C<%Net::Hotline::Constants::HTLC_COLORS> contains color
number-to-name mappings.

=item event_loop_handler CODE (SELF, IDLE)

Next cycle in the event loop.  Idle events only occur when non-blocking i/o
is active.

    IDLE        True if the event is an idle event.

=item icon_handler CODE (SELF, USER, OLD_ICON, NEW_ICON)

A user changed icon in the userlist.

    USER        A Net::Hotline::User object.
    OLD_ICON    The user's previous icon number.
    NEW_ICON    The user's new icon number.

=item join_handler CODE (SELF, USER)

A user joined the server.

    USER        A Net::Hotline::User object.

=item leave_handler CODE (SELF, USER)

A user left the server.

    USER        A Net::Hotline::User object.

=item msg_handler CODE (SELF, USER, TEXT, REPLY-TO)

A private message arrived.

    USER        Reference to the sender's Net::Hotline::User object.
    TEXT        Reference to the message text.
    REPLY-TO    Reference to the text to which this is a reply (if any)   

=item news_posted_handler CODE (SELF, TEXT)

A news post was made by another user.

    TEXT        Reference to the news post text.

=item nick_handler CODE (SELF, USER, OLD_NICK, NEW_NICK)

A user changed nickname in the userlist.

    USER        A Net::Hotline::User object.
    OLD_NICK    The user's previous nickname.
    NEW_NICK    The user's new nickname.

=item pchat_action_handler (SELF, REF, TEXT)

A new private chat action appeared.

    REF         Private chat reference number.
    TEXT        Reference to the chat action text.

=item pchat_chat_handler (SELF, REF, TEXT)

New private chat appeared.

    REF         Private chat reference number.
    TEXT        Reference to the chat text.

=item pchat_invite_handler (SELF, REF, SOCKET, NICK)

An invitation to private chat arrived.

    REF         Private chat reference number.
    SOCKET      Socket number of the inviting user.
    NICK        Nick of the inviting user.

=item pchat_join_handler (SELF, PCHAT, SOCKET)

A user joined a private chat.

    PCHAT       A Net::Hotline::PrivateChat object.
    SOCKET      Socket number of the joining user.

=item pchat_leave_handler (SELF, PCHAT, SOCKET)

A user left a private chat.

    PCHAT       A Net::Hotline::PrivateChat object.
    SOCKET      Socket number of the leaving user.

Note that the user who left will no longer be in the private chat object's
userlist.

=item pchat_subject_handler (SELF, REF, TEXT)

Private chat subject changed.

    REF         Private chat reference number.
    TEXT        Reference to the subject text.

=item quit_handler CODE (SELF, TEXT)

The server was shutdown politely.

    TEXT        Reference to shutdown message text.

=item server_msg_handler CODE (SELF, TEXT)

A server message arrived.

    TEXT        Reference to the message text.

=back

=head3 TASKS

=over 4

=item ban_handler CODE (SELF, TASK)

Ban user task completed.

    TASK        A Net::Hotline::Task object.

=item delete_file_handler CODE (SELF, TASK)

A file or folder was deleted.

    TASK        A Net::Hotline::Task object.

=item file_info_handler CODE (SELF, TASK, INFO)

File information received.

    TASK        A Net::Hotline::Task object.
    INFO        A Net::Hotline::FileInfoItem object.

=item file_list_handler CODE (SELF, TASK)

File list received.

    TASK        A Net::Hotline::Task object.

=item get_file_handler CODE (SELF, TASK, REF, SIZE)

A file download is ready to begin.

    TASK        A Net::Hotline::Task object.
    REF         Download reference number.
    SIZE        Size of download in bytes.

If you do not set a handler for C<get_file()>, a default handler will be
used regardless of your C<default_handlers()> setting.  The default handler
simply does:

    SELF->recv_file(TASK, REF, SIZE);

which initiates the file download and does not return until the download
has completed.  If you want to download in the background, call C<fork()>
(or something similar) in your handler routine.

=item kick_handler CODE (SELF, TASK)

Disconnect user task completed.

    TASK        A Net::Hotline::Task object.

=item login_handler CODE (SELF, TASK)

Login task completed.

    TASK        A Net::Hotline::Task object.

=item move_file CODE (SELF, TASK)

A file or folder was moved.

    TASK        A Net::Hotline::Task object.

=item new_folder CODE (SELF, TASK)

New folder created.

    TASK        A Net::Hotline::Task object.

=item news_handler CODE (SELF, TASK)

The news has arrived and is now available via the C<news()> method.

    TASK        A Net::Hotline::Task object.

=item pchat_accept_handler (SELF, TASK, PCHAT)

You have joined a private chat.

    TASK        A Net::Hotline::Task object.
    PCHAT       A Net::Hotline::PrivateChat object.

=item pchat_create (SELF, TASK, PCHAT)

New private chat created.

    TASK        A Net::Hotline::Task object.
    PCHAT       A Net::Hotline::PrivateChat object.

Note that you do not have to save the private chat object yourself.  The
client object keeps track of all private chats it is currently engaged in (the
list is accessible via the C<pchats()> method), updates the userlists as users
join and leave, and deletes the objects when you leave the private chat.

=item post_news_handler CODE (SELF, TASK)

News post task completed.

    TASK        A Net::Hotline::Task object.

=item put_file_handler CODE (SELF, TASK, REF, SIZE, RFLT)

A file upload is ready to begin.

    TASK        A Net::Hotline::Task object.
    REF         Download reference number.
    SIZE        Size of the upload in bytes.
    RFLT        Data needed to resume an upload.

If you do not set a handler for C<put_file()>, a default handler will be
used regardless of your C<default_handlers()> setting.  The default handler
simply does:

    SELF->send_file(TASK, REF, SIZE, RFLT);

which initiates the file upload and does not return until the upload has
completed.  If you want to upload in the background, call C<fork()> (or
something similar) in your handler routine.

=item send_msg_handler CODE (SELF, TASK)

Private message sent.

    TASK        A Net::Hotline::Task object.

=item set_file_info_handler CODE (SELF, TASK)

File information set (this includes both renaming and setting file
comments).

    TASK        A Net::Hotline::Task object.

=item task_error_handler CODE (SELF, TASK)

A task error ocurred.

    TASK        A Net::Hotline::Task object.

=item user_info_handler CODE (SELF, TASK)

User information received.

    TASK        A Net::Hotline::Task object.

=item user_list_handler CODE (SELF, TASK)

User list received.

    TASK        A Net::Hotline::Task object.

=back

=head2 MISCELLANEOUS

=over 4

=item debug EXPR

If EXPR is omitted, returns the debugging status (off by default),
otherwise sets debugging status to EXPR (true means debugging is on).

=item version

Returns the Net::Hotline::Client version string.

=back

=head1 TO DO

=over 4

=item *

User administration.

=back

=head1 BUGS

Please send bug reports to siracusa@mindspring.com.

=head1 AUTHOR

John C. Siracusa (siracusa@mindspring.com)

=head1 COPYRIGHT

Copyright(c) 1999 by John C. Siracusa.  All rights reserved.  This program is
free software; you can redistribute it and/or modify it under the same terms
as Perl itself.
