from twisted.protocols import basic
from twisted.internet import defer
import logging


log = logging.getLogger(__name__)


class ConsoleControl(basic.LineReceiver):
    from os import linesep as delimiter

    def __init__(self):
        self.connected = False
        self.buffer = []
        self.command_handlers = {}
        self.current_handler = None

    def start(self, command_handlers):
        self.command_handlers = {h.command: h for h in command_handlers}
        self.current_handler = None
        self.send_initial_prompt()
        return defer.succeed(True)

    def connectionMade(self):
        self.connected = True
        if self.buffer:
            self.send(self.buffer)
            self.buffer = []

    def send_initial_prompt(self):
        self.sendLine("")
        self.sendLine("In this early release of LBRY, some functions will not work\n"
                      "until you have downloaded a full copy of our blockchain. To\n"
                      "check whether you've caught up with the blockchain, use the\n"
                      "command 'get-blockchain-status'.\n\n"
                      "If, for example, you are unable to download some files or\n"
                      "your balance is showing 0 when you know it shouldn't be, it\n"
                      "is likely that the culprit is the blockchain.\n\n"
                      "You should have received 1000 LBC the first time you ran\n"
                      "this program. If you did not, let us know!\n\n"
                      "Welcome to lbrynet-console!")
        self.sendLine("")
        self.sendLine("Enter a command. Try 'get wonderfullife' or 'help' to see more options.")
        self.show_prompt()

    def send(self, s):
        self.transport.write(s)

    def write(self, s):
        if self.connected is False:
            self.buffer.append(s)
        else:
            self.send(s)

    def flush(self):
        if self.connected is True and self.buffer:
            self.send(self.buffer)
            self.buffer = []

    def show_prompt(self):
        self.send("> ")

    def show_quick_help(self):
        self.sendLine("Available commands:")
        self.sendLine("")
        showed_help_all = False
        sorted_handlers = sorted(self.command_handlers.items(), key=lambda x: x[0])
        sorted_handlers = sorted(sorted_handlers, key=lambda x: x[1].priority, reverse=True)
        for command, handler in sorted_handlers:
            if handler.priority > 0:
                if showed_help_all is False and handler.priority < 10:
                    self.sendLine("help-all - Show the full list of available commands")
                    showed_help_all = True
                self.sendLine(command + " - " + handler.short_help)
        self.sendLine("")
        self.sendLine("For more information about any command type 'help <command>'")

    def show_full_help(self):
        self.sendLine("Available commands:")
        self.sendLine("")
        for command, handler in sorted(self.command_handlers.items(), key=lambda x: x[0]):
            self.sendLine(command + " - " + handler.short_help)
        self.sendLine("")
        self.sendLine("For more information about any command type 'help <command>'")

    def handler_done(self):
        self.current_handler = None
        self.show_prompt()

    def handler_failed(self, err):
        self.current_handler = None
        self.sendLine("An error occurred:")
        self.sendLine(err.getTraceback())
        self.show_prompt()

    def lineReceived(self, line):
        if not self.command_handlers:
            return
        if self.current_handler is None:
            words = line.split()
            if len(words) == 0:
                self.show_prompt()
                return
            command, args = words[0], words[1:]
            if command == "help":
                if len(args) == 0:
                    self.show_quick_help()
                    self.show_prompt()
                    return
                if args[0] in self.command_handlers:
                    self.sendLine(self.command_handlers[args[0]].full_help)
                    self.show_prompt()
                    return
                if args[0] == "help-all":
                    self.sendLine("Show the full list of available commands!")
                    self.show_prompt()
                    return
                self.sendLine("Can't help you with '%s'. Sorry!" % args[0])
                self.show_prompt()
                return
            elif command == "help-all":
                self.show_full_help()
                self.show_prompt()
                return
            if command in self.command_handlers:
                command_handler = self.command_handlers[command]
            else:
                candidates = [k for k in self.command_handlers.keys() if k.startswith(command)]
                if len(candidates) == 0:
                    self.sendLine("Unknown command. Type 'help' for a list of commands.")
                    self.show_prompt()
                    return
                if len(candidates) >= 2:
                    l = "Ambiguous command. Matches: "
                    for candidate in candidates:
                        l += candidate
                        l += ", "
                    l = l[:-2]
                    l += l
                    self.sendLine(l)
                    self.show_prompt()
                    return
                else:
                    command_handler = self.command_handlers[candidates[0]]
            try:
                self.current_handler = command_handler.get_handler(self)
            except:
                self.current_handler = None
                import traceback
                self.sendLine(traceback.format_exc())
                log.error(traceback.format_exc())
                self.show_prompt()
                return
            try:
                self.current_handler.start(*args)
            except TypeError:
                self.current_handler = None
                self.sendLine("Invalid arguments. Type 'help <command>' for the argument list.")
                import traceback
                log.error(traceback.format_exc())
                self.show_prompt()
                return
            except:
                self.current_handler = None
                import traceback
                self.sendLine(traceback.format_exc())
                log.error(traceback.format_exc())
                self.show_prompt()
                return
            self.current_handler.finished_deferred.addCallbacks(lambda _: self.handler_done(),
                                                                self.handler_failed)
        else:
            try:
                self.current_handler.handle_line(line)
            except Exception as e:
                self.current_handler = None
                import traceback
                self.sendLine(traceback.format_exc())
                log.error(traceback.format_exc())
                self.show_prompt()
                return