help strings for commands

[saartuer.git] / tyshell

diff --git a/tyshell b/tyshell
index 0b9b94361fde70972e65c48a897716e7ee8f9316..f30b9d797928f06d10dda8c3638480c04df70d11 100755 (executable)
--- a/tyshell
+++ b/tyshell
@@ -5,6 +5,8 @@ import shlex
 import sys
 import subprocess
 import socket
+import pwd
+import grp
 
 tuerSock = "/run/tuer.sock"
 
@@ -16,11 +18,14 @@ except IOError:
     pass
 import atexit
 atexit.register(readline.write_history_file, histfile)
-atexit.register(print, "Bye")
 
 # available commands
 def helpcmd(c):
-       print("Available commands: %s" % ", ".join(sorted(longcommands.keys())))
+       if (len(c) > 1):
+               print(commands.get(c[1],(None,'Can\'t find help for command %s'%(c[1])))[1])
+       else:
+               print("Available commands: %s" % ", ".join(sorted(commands.keys())))
+               print("Use 'help command' to get more information on the command 'command'")
 
 def extcmd(cmd):
        def run(c):
@@ -31,60 +36,46 @@ def extcmd(cmd):
 
 def sendcmd(addr, cmd):
        def run(c):
-               print("Running %s..." % (cmd))
+               print("206 Sending command %s..." % (cmd))
                s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
                s.connect(addr)
+               s.settimeout(60.0)
                s.send(cmd.encode())
-               data = s.recv(4)
+               data = s.recv(256)
                s.close()
-               print("...done")
-               if data != b'1':
-                       print("Received unexpected answer %s" % str(data))
+               print(data.decode('utf-8'))
        return run
 
 def exitcmd(c):
-       sys.exit(0)
-
-commands = {
-       'exit': exitcmd,
-       'help': helpcmd,
-       'open': sendcmd(tuerSock, 'open'),
-       'close': sendcmd(tuerSock, 'close'),
-       'buzz': sendcmd(tuerSock, 'buzz'),
-}
+       print("Bye")
+       return True
 
-# command convenience shortcuts
-def filterCommonPrefix (strings, length):
-       # ignores duplicates in the string list "strings"
-       toremove=[]
-       for a in strings:
-               for b in strings:
-                       if a != b:
-                               if a[:length] == b[:length]:
-                                       toremove.append(a)
-                                       toremove.append(b)
-       ret = list(strings) # copy
-       for x in toremove:
-               try:
-                       ret.remove(x)
-               except ValueError:
-                       pass
-       return ret
+def whocmd(c):
+       for n in grp.getgrnam("tuer").gr_mem:
+               p = pwd.getpwnam(n)
+               print (p.pw_name, " - ", p.pw_gecos)
 
-def shortcutify (dic):
-       maxlen = 0
-       for x in dic.keys():
-               if len(x) > maxlen:
-                       maxlen = len(x)
-       for i in range(maxlen):
-               shortable = filterCommonPrefix (dic.keys(), i)
-               for x in shortable:
-                       dic[x[:i]] = dic[x]
-       return dic # only for convenience, as dic is passed by reference
+def alias (cmds, aliases):
+       for newname, oldname in aliases.items():
+               cmds[newname] = cmds[oldname]
+       return cmds
 
-longcommands = commands.copy()
-shortcutify (commands)
+commands = alias({
+       'exit': (exitcmd, 'Quits this shell'),
+       'help': (helpcmd, 'Helps you getting to know the available commands'),
+       'open': (sendcmd(tuerSock, 'unlock'), 'Will try to unlock the apartment door'),
+       'buzz': (sendcmd(tuerSock, 'buzz'), 'Will buzz the buzzer for the street door'),
+       'who': (whocmd, 'Shows the list of people, who are allowed to control this system'),
+},{
+       # aliases
+       'unlock': 'open',
+})
 
+def complete_command(cmd):
+       '''returns a list of commands (as strings) starting with cmd'''
+       return list(filter(lambda x: x.startswith(cmd), commands.keys()))
+readline.set_completer(lambda cmd, num: (complete_command(cmd)+[None])[num]) # wrap complete_command for readline's weird completer API
+readline.parse_and_bind("tab: complete") # run completion on tab
 
 # input loop
 print("Welcome to tyshell. Use help to see what you can do.")
@@ -96,12 +87,22 @@ while True:
                break
        command = shlex.split(command)
        if not len(command): continue
-       # execute command
-       if command[0] in commands:
+       # find suiting commands
+       if command[0] in commands: # needed in case a complete command is a prefix of another one
+               cmdoptions = [command[0]]
+       else:
+               cmdoptions = complete_command(command[0])
+       # check how many we found
+       if len(cmdoptions) == 0: # no commands fit prefix
+               print("Command %s not found. Use help." % command[0])
+       elif len(cmdoptions) == 1: # exactly one command fits (prefix)
                try:
-                       commands[command[0]](command)
+                       res = commands[cmdoptions[0]][0](command)
+                       if res: break
                except Exception as e:
                        print("Error while executing %s: %s" % (command[0], str(e)))
-       else:
-               print("Command %s not found. Use help." % command[0])
+       else: # multiple commands fit the prefix
+               print("Ambiguous command prefix, please choose one of the following:")
+               print("\t", " ".join(cmdoptions))
+               # TODO: put current "command[0]" into the shell for the next command, but such that it is deletable with backspace