#!/usr/bin/env perl
use strict;
use warnings;

=head1 DESCRIPTION

This is a simple command-line interface to Hiveminder that loosely
emulates the interface of Lifehacker.com's todo.sh script.

=cut

use Encode ();
use YAML ();
use LWP::UserAgent;
use Number::RecordLocator;
use Getopt::Long;
use Pod::Usage;
use Email::Address;
use Fcntl qw(:mode);

our $CONFFILE = "$ENV{HOME}/.hiveminder";
our %config = ();
our $ua = LWP::UserAgent->new;
our $locator = Number::RecordLocator->new();
our $default_query = "not/complete/starts/before/tomorrow/accepted/but_first/nothing";
our $pending_query = "pending/not/complete";
our $requests_query = "requestor/me/not/owner/me/not/complete";
our %args;

$ua->cookie_jar({});

# Load the user's proxy settings from %ENV
$ua->env_proxy;

my $encoding;
eval {
    require Term::Encoding;
    $encoding = Term::Encoding::get_encoding();
};
$encoding ||= "utf-8";

binmode STDOUT, ":encoding($encoding)";

main();

sub main {
    GetOptions(\%args,
               "tags=s",
               "tag=s@", "group=s",
               "priority|pri=s",
               "due=s",
               "hide=s",
               "owner=s",
               "help",
               "config=s",)
      or pod2usage(2);

    $CONFFILE = $args{config} if $args{config};

    pod2usage(0) if $args{help};

    setup_config();

    push @{$args{tag}}, split /\s+/, $args{tags} if $args{tags};

    if($args{priority}) {
        $args{priority} = priority_from_string($args{priority})
          unless $args{priority} =~ /^[1-5]$/;
        die("Invalid priority: $args{priority}")
          unless$args{priority} =~ /^[1-5]$/;
    }

    $args{owner} ||= "me";

    do_login() or die("Bad username/password -- edit $CONFFILE and try again.");

    my %commands = (
        list     => \&list_tasks,
        ls       => \&list_tasks,
        add      => \&add_task,
        do       => \&do_task,
        done     => \&do_task,
        del      => \&del_task,
        rm       => \&del_task,
        edit     => \&edit_task,
        tag      => \&tag_task,
        pending  => sub {list_tasks($pending_query)},
        accept   => \&accept_task,
        decline  => \&decline_task,
        assign   => \&assign_task,
        requests => sub {list_tasks($requests_query)},
        hide     => \&hide_task,
        comment  => \&comment_task,
        dl       => \&download_textfile,
        download => \&download_textfile,
        ul       => \&upload_textfile,
        upload   => \&upload_textfile,
       );
    
    my $command = shift @ARGV || "list";
    $commands{$command} or pod2usage(-message => "Unknown command: $command", -exitval => 2);

    $commands{$command}->();
}


=head1 CONFIG FILE

These methods deal with loading the config file, and populating it
with selections read from the terminal on our first run.

=cut

sub setup_config {
    check_config_perms() unless($^O eq 'MSWin32');
    load_config();
    check_config();

}

sub check_config_perms {
    return unless -e $CONFFILE;
    my @stat = stat($CONFFILE);
    my $mode = $stat[2];
    if($mode & S_IRGRP || $mode & S_IROTH) {
        warn("Config file $CONFFILE is readable by someone other than you, fixing.");
        chmod 0600, $CONFFILE;
    }
}

sub load_config {
    return unless(-e $CONFFILE);
    %config = %{YAML::LoadFile($CONFFILE) || {}};
    my $sid = $config{sid};
    if($sid) {
        my $uri = URI->new($config{site});
        $ua->cookie_jar->set_cookie(0, 'JIFTY_SID_' . $uri->port,
                                    $sid, '/', $uri->host, $uri->port,
                                    0, 0, undef, 1);
    }
    if($config{site}) {
        # Somehow, localhost gets normalized to localhost.localdomain,
        # and messes up HTTP::Cookies when we try to set cookies on
        # localhost, since it doesn't send them to
        # localhost.localdomain.
        $config{site} =~ s/localhost/127.0.0.1/;
    }
}

sub check_config {
    new_config() unless $config{email};
}

sub new_config {
    print <<"END_WELCOME";
Welcome to todo.pl! before we get started, please enter your
Hiveminder username and password so we can access your tasklist.

This information will be stored in $CONFFILE, should you ever need to
change it.

END_WELCOME

    $config{site} ||= 'http://hiveminder.com';

    while (1) {
        print "First, what's your email address? ";
        $config{email} = <stdin>;
        chomp($config{email});

        use Term::ReadKey;
        print "And your password? ";
        ReadMode('noecho');
        $config{password} = <stdin>;
        chomp($config{password});
        ReadMode('restore');

        print "\n";

        last if do_login();
        print "That combination doesn't seem to be correct. Try again?\n";
    }

    save_config();
}

sub save_config {
    YAML::DumpFile($CONFFILE, \%config);
    chmod 0600, $CONFFILE;
}

=head1 TASKS

methods related to manipulating tasks -- the meat of the script.

=cut

sub list_tasks {
    my $query = shift || $default_query;

    my $tag;
    $query .= "/tag/$tag" while $tag = shift @{$args{tag}};

    for my $key qw(group priority due) {
        $query .= "/$key/$args{$key}" if $args{$key};
    }

    $query .= "/owner/$args{owner}";

    my $tasks = download_tasks($query);
    
    for my $t (@$tasks) {
        printf "%4s ", $locator->encode($t->{id});
        print '(' . priority_to_string($t->{priority}) . ') ' if $t->{priority} != 3;
        print "(Due " . $t->{due} . ") " if $t->{due};
        print $t->{summary};
        if($t->{tags}) {
            print ' [' . $t->{tags} . ']';
        }

        $t->{owner} =~ s/<nobody>/<nobody\@localhost>/;
        $t->{requestor} =~ s/<nobody>/<nobody\@localhost>/;
        
        my ($owner) = Email::Address->parse($t->{owner});
        my ($requestor) = Email::Address->parse($t->{requestor});

        my $not_owner = lc $owner->address ne lc $config{email};
        my $not_requestor = lc $requestor->address ne lc $config{email};
        if( $t->{group} || $not_owner || $not_requestor ) {
            print ' (';
            print join(", ",
                       $t->{group} || "personal",
                       $not_requestor ? "for " . $requestor->name : (),
                       $not_owner ? "by " . $owner->name : (),
                      );
            print ')';
        }
        
        print "\n";
    }
}

sub do_task {
    my $task = get_task_id('complete');
    my $result = call(UpdateTask =>
                      id         => $task,
                      complete   => 1);
    result_ok($result, "Completed task");
}

sub add_task {
    my $summary = join(" ",@ARGV) or pod2usage(-message => "Must specify a task description");
    my %task = %{args_to_task()};
    $task{summary} = $summary;

    my $result = call(CreateTask => %task);
    result_ok($result, "Created task");
}

sub edit_task {
    my $task = get_task_id('edit');
    my $summary = join(" ",@ARGV);
    my %task = %{args_to_task()};
    $task{id} = $task;
    $task{summary} = $summary if $summary;

    my $result = call(UpdateTask => %task);
    result_ok($result, "Updated task");
}

sub tag_task {
    my $task = get_task_id('tag');
    my @tags = @ARGV;

    my $tasks = download_tasks("id/$task");
    my $tags = $tasks->[0]{tags};

    my $result = call(UpdateTask =>
                      id      => $task,
                      tags    => $tags . " " . join_tags(@tags));

    result_ok($result, "Tagged task");
}

sub del_task {
    my $task = get_task_id('delete');
    my $result = call(DeleteTask => id => $task);

    result_ok($result, "Deleted task");
}

sub accept_task {
    my $task = get_task_id('accept');
    my $result = call(UpdateTask =>
                      id       => $task,
                      accepted => 'TRUE');
    result_ok($result, "Accepted task");
}


sub decline_task {
    my $task = get_task_id('accept');
    my $result = call(UpdateTask =>
                      id       => $task,
                      accepted => 'FALSE');
    result_ok($result, "Declined task");
}

sub assign_task {
    my $task = get_task_id('assign');
    my $owner = shift @ARGV or die('Need an owner to assign task to');
    my $result = call(UpdateTask => id => $task, owner_id => $owner);
    result_ok($result, "Assigned task to $owner");
}

sub hide_task {
    my $task = get_task_id('hide');
    my $when = join(" ", @ARGV) or die('Need a date to hide the task until');
    my $result = call(UpdateTask =>
                      id         => $task,
                      starts     => $when);
    result_ok($result, "Hid task until $when");
}

sub comment_task {
    my $task = get_task_id('comment on');
    if(-t STDIN) {
        print "Type your comment now. End with end-of-file or a dot on a line by itself.\n";
    }
    my $comment;
    while(<STDIN>) {
        chomp;
        last if $_ eq ".";
        $comment .= "\n$_";
    }

    my $result = call(UpdateTask =>
                      id         => $task,
                      comment    => $comment);
    result_ok($result, "Commented on task");
}

sub get_task_id {
    my $action = shift;
    my $task = shift @ARGV or pod2usage(-message => "Need a task-id to $action.");
    return $locator->decode($task) or die("Invalid task ID");
}

sub download_textfile {
    my $query = shift || $default_query;
    my $filename = shift @ARGV || 'tasks.txt';

    my $tag;
    $query .= "/tag/$tag" while $tag = shift @{$args{tag}};

    for my $key qw(group priority due) {
        $query .= "/$key/$args{$key}" if $args{$key};
    }

    $query .= "/owner/$args{owner}";

    my $result = call(DownloadTasks =>
                      query  => $query,
                      format => 'sync');

    # perl automatically does TRT with $filename eq '-'
    open (my $file, ">:utf8", $filename) || die("Can't open file '$filename': $!");

    print $file $result->{_content}{result};
}

sub upload_textfile {
    my $filename = shift @ARGV;
    pod2usage(-message => "Need to specify a file to upload.",
              -exitval => 1
    ) unless $filename;

    open (my $file, "< $filename"); 

    local $/;
    my $content = <$file>;

    my $result = call(UploadTasks =>
                        content => $content,
                        format => 'sync' );

    print STDOUT $result->{message} . "\n";
}


=head1 BTDT API

These functions deal with calling the BTDT/Jifty api to communicate
with the server.

=cut

sub do_login {
    return 1 if $config{sid};
    my $result = call(Login =>
                      address  => $config{email},
                      password => $config{password});
    if(!$result->{failure}) {
        $config{sid} = get_session_id();
        save_config();
        return 1;
    }
    return;
}

sub get_session_id {
    return undef unless $ua->cookie_jar->as_string =~ /JIFTY_SID_\d+=([^;]+)/;
    return $1;
}

sub download_tasks {
    my $query = shift || $default_query;

    my $result = call(DownloadTasks =>
                      query  => $query,
                      format => 'yaml');
    return YAML::Load($result->{_content}{result});
}

sub call ($@) {
    my $class   = shift;
    my %args    = (@_);
    my $moniker = 'fnord';

    my $res = $ua->post(
        $config{site} . "/__jifty/webservices/yaml",
        {   "J:A-$moniker" => $class,
            map { ( "J:A:F-$_-$moniker" => $args{$_} ) } keys %args
        }
    );

    if ( $res->is_success ) {
        return YAML::Load( Encode::decode_utf8($res->content) )->{$moniker};
    } else {
        die $res->status_line;
    }
}

=head2 result_ok RESULT, MESSAGE

Make sure that a result returned by C<call> indicates success. If so,
print MESSAGE. Otherwise, die with a descriptive error.

=cut

sub result_ok {
    my $result = shift;
    my $message = shift;

    if(!$result->{failure}) {
        print "$message\n";
    } else {
        die(YAML::Dump($result));
    }
    
}

=head2 PRIORITY

Conversions between text priorities ('A' - 'Z'), and the 1-5 integer
scale Hiveminder uses internally.

=cut

sub priority_to_string {
    my $pri = shift;
    return chr(ord('A') + 5 - $pri);
}

sub priority_from_string {
    my $pri = lc shift;
    return 5 + ord('a') - ord($pri) if $pri =~ /^[a-e]$/;
    my %primap = (
        lowest  => 1,
        low     => 2,
        normal  => 3,
        high    => 4,
        highest => 5
       );
    return $primap{$pri} || $pri;
}

=head2 args_to_task

Convert argument passed on the command-line into a hash appropriate
for passing as arguments to BTDT actions.

=cut

sub args_to_task {
    my %task;

    $task{tags} = join_tags(@{$args{tag}}) if $args{tag};
    $task{group_id} = $args{group} if $args{group};
    $task{owner_id} = $config{email};
    $task{priority} = $args{priority} if $args{priority};
    $task{due} = $args{due} if $args{due};
    $task{starts} = $args{hide} if $args{hide};
    
    return \%task;
}

sub join_tags {
    my @tags = @_;
    return join(" ", map {'"' . $_ . '"'} @tags);
}

__END__

=head1 NAME

todo.pl - a command-line interface to Hiveminder

=head1 SYNOPSIS

  todo.pl [options] list
  todo.pl [options] add <summary>
  todo.pl [options] edit <task-id> [summary]

  todo.pl tag <task-id> tag1 tag2

  todo.pl done <task-id>
  todo.pl del|rm <task-id>

  todo.pl [options] pending
  todo.pl accept <task-id>
  todo.pl decline <task-id>

  todo.pl assign <task-id> <email>
  todo.pl [options] requests

  todo.pl hide <task-id> date

  todo.pl comment <task-id>

  todo.pl [options] download [file]
  todo.pl upload <file>

    Options:
       --group                          Operate on tasks in a group
       --tag                            Operate on tasks with a given tag
       --pri                            Operate on tasks with a given priority
       --due                            Operate on tasks due on a given day
       --hide                           Operate on tasks hidden until this day
       --owner                          Operate on tasks with a given owner


  todo.pl list
        List all tasks in your todo list.

  todo.pl --tag home --tag othertag --group personal list
        List all personl tasks (not in a group with tags 'home' and 'othertag'.

  todo.pl --tag cli --group hiveminders edit 3G Implement todo.pl
        Move task 3G into the hiveminders group, set its tags to
        "cli", and change the summary.

  todo.pl --tag "" 4J
        Delete all tags from task 4J

  todo.pl tag 4J home
        Add the tag ``home'' to task 4J

=cut