fish-shell/share/completions/schtasks.fish

function __schtasks_list_tasks --description 'Helper function to list tasks'
  schtasks | awk '/^=/ { show = 1; next } show { print $1 }'
end

function __schtasks_change_generate_args --argument-names previous_token
  if test "$previous_token" = '/tn'
    __schtasks_list_tasks
    return
  end

  if string match --regex --quiet -- "$previous_token" '^/r?u$'
    wmic useraccount get name | tail +2
    return
  end

  if test "$previous_token" = '/rp'
    __fish_generate_password
    return
  end

  if not __fish_seen_argument --windows 'et' --windows 'du'
    echo -e '/et\tSpecify the end time for the task
/du\tA value that specifies the duration to run the task'
  end

  if not __fish_seen_argument --windows 'ENABLE' --windows 'DISABLE'
    echo -e '/ENABLE\tSpecify to enable the scheduled task
/DISABLE\tSpecify to disable the scheduled task'
  end

  echo -e '/tn\tIdentify the task to be changed
/s\tSpecify the name or IP address of a remote computer
/u\tRun this command with the permissions of the specified user account
/p\tSpecify the password of the user account specified in the /u parameter
/ru\tChange the user name under which the scheduled task has to run
/rp\tSpecify a new password for the existing user account, or the user account specified by /ru
/tr\tChange the program that the task runs
/st\tSpecify the start time for the task
/ri\tSpecify the repetition interval for the scheduled task
/k\tStop the program that the task runs at the time specified by /et or /du
/sd\tSpecify the first date on which the task should be run
/ed\tSpecify the last date on which the task should be run
/it\tSpecify to run the scheduled task only when the run as user is logged on to the computer
/z\tSpecify to delete the task upon the completion of its schedule
/?\tShow help'
end

function __schtasks_create_generate_args --argument-names previous_token
  if test "$previous_token" = '/sc'
    echo -e 'MINUTE\tSpecify the number of minutes before the task should run
HOURLY\tSpecify the number of hours before the task should run
DAILY\tSpecify the number of days before the task should run
WEEKLY\tSpecify the number of weeks before the task should run
MONTHLY\tSpecify the number of months before the task should run
ONCE\tSpecify that that task runs once at a specified date and time
ONSTART\tSpecify that the task runs every time the system starts
ONLOGON\tSpecify that the task runs whenever a user logs on
ONIDLE\tSpecify that the task runs whenever the system is idle for a specified period of time'
    return
  end

  if string match --regex --quiet -- "$previous_token" '^/r?u$'
    wmic useraccount get name | tail +2
    return
  end

  if test "$previous_token" = '/rp'
    __fish_generate_password
    return
  end

  if test "$previous_token" = '/mo'
    echo -e 'MINUTE\tSpecify that the task runs every n minutes
HOURLY\tSpecify that the task runs every n hours
DAILY\tSpecify that the task runs every n days
WEEKLY\tSpecify that the task runs every n weeks
MONTHLY\tSpecify that the task runs every n months
ONCE\tSpecify that the task runs once
ONSTART\tSpecify that the task runs at startup
ONLOGON\tSpecify that the task runs when the user specified by the /u parameter logs on
ONIDLE\tSpecify that the task runs after the system is idle for the number of minutes specified by /i'
    return
  end

  if not __fish_seen_argument --windows 'et' --windows 'du'
    echo -e '/et\tSpecify the time of day that a minute or hourly task schedule ends
/du\tSpecify a maximum length of time for a minute or hourly schedule'
  end

  echo -e '/sc\tSpecify the schedule type
/tn\tSpecify a name for the task
/tr\tSpecify the program or command that the task runs
/s\tSpecify the name or IP address of a remote computer
/u\tRun this command with the permissions of the specified user account
/p\tSpecify the password of the user account specified in the /u parameter
/ru\tRun the task with permissions of the specified user account
/rp\tSpecify a the password for the existing user account, or the user account specified by /ru
/mo\tSpecify how often the task runs within its schedule type
/d\tSpecify how often the task runs within its schedule type
/m\tSpecify a month or months of the year during which the scheduled task should run
/i\tSpecify how many minutes the computer is idle before the task starts
/st\tSpecify the start time for the task
/ri\tSpecify the repetition interval for the scheduled task
/k\tStop the program that the task runs at the time specified by /et or /du
/sd\tSpecify the date on which the task schedule starts
/ed\tSpecify the date on which the schedule ends
/it\tSpecify to run the scheduled task only when the run as user is logged on to the computer
/z\tSpecify to delete the task upon the completion of its schedule
/f\tSpecify to create the task and suppress warnings if the specified task already exists
/?\tShow help'
end

function __schtasks_delete_generate_args --argument-names previous_token
  if test "$previous_token" = '/tn'
    __schtasks_list_tasks
    return
  end

  if test "$previous_token" = '/u'
    wmic useraccount get name | tail +2
    return
  end

  echo -e '/tn\tIdentify the task to be deleted
/f\tSuppress the confirmation message
/s\tSpecify the name or IP address of a remote computer
/u\tRun this command with the permissions of the specified user account
/p\tSpecify the password of the user account specified in the /u parameter
/?\tShow help'
end

function __schtasks_end_generate_args --argument-names previous_token
  if test "$previous_token" = '/tn'
    __schtasks_list_tasks
    return
  end

  if test "$previous_token" = '/u'
    wmic useraccount get name | tail +2
    return
  end

  echo -e '/tn\tIdentify the task that started the program
/s\tSpecify the name or IP address of a remote computer
/u\tRun this command with the permissions of the specified user account
/p\tSpecify the password of the user account specified in the /u parameter
/?\tShow help'
end

function __schtasks_query_generate_args --argument-names previous_token
  if test "$previous_token" = '/fo'
    echo -e 'TABLE
LIST
CSV'
    return
  end

  if test "$previous_token" = '/u'
    wmic useraccount get name | tail +2
    return
  end

  echo -e '/fo\tSpecify the output format
/nh\tRemove column headings from the table display
/v\tAdd the advanced properties of the task to the display
/s\tSpecify the name or IP address of a remote computer
/u\tRun this command with the permissions of the specified user account
/p\tSpecify the password of the user account specified in the /u parameter
/?\tShow help'
end

function __schtasks_run_generate_args --argument-names previous_token
  if test "$previous_token" = '/tn'
    __schtasks_list_tasks
    return
  end

  if test "$previous_token" = '/u'
    wmic useraccount get name | tail +2
    return
  end

  echo -e '/tn\tIdentify the task to start
/s\tSpecify the name or IP address of a remote computer
/u\tRun this command with the permissions of the specified user account
/p\tSpecify the password of the user account specified in the /u parameter
/?\tShow help'
end

function __schtasks_generate_args --description 'Function to generate args'
  if not __fish_seen_argument --windows change --windows create --windows delete --windows end \
    --windows query --windows run
    echo -e '/change\tChange one or more properties of a task
/create\tSchedule a new task
/delete\tDelete a scheduled task
/end\tStop a program started by a task
/query\tDisplay tasks scheduled to run on the computer
/run\tStart a scheduled task immediately'
    return
  end

  set --local previous_token (commandline --tokenize --cut-at-cursor)[-1]
  
  if __fish_seen_argument --windows change
    __schtasks_change_generate_args "$previous_token"
  else if __fish_seen_argument --windows create
    __schtasks_create_generate_args "$previous_token"
  else if __fish_seen_argument --windows delete
    __schtasks_delete_generate_args "$previous_token"
  else if __fish_seen_argument --windows end
    __schtasks_end_generate_args "$previous_token"
  else if __fish_seen_argument --windows query
    __schtasks_query_generate_args "$previous_token"
  else if __fish_seen_argument --windows run
    __schtasks_run_generate_args "$previous_token"
  end
end

complete --command schtasks --no-files --arguments '(__schtasks_generate_args)'