from dataclasses import dataclass
from pathlib import Path


class Plugin:

    REQUIRED_CONFIGS = []

    def __init__(self, bot):
        self.bot = bot
        self.name = self.__class__.__name__.lower()[:-6]  # Remove "Plugin".
        self.config = self._get_config()
        self.is_ready = self._check_config()

    @property
    def callbacks(self):
        """List of callback types available for this plugin."""
        return {
            cb[3:]: getattr(self, cb)
            for cb in dir(self)
            if cb.startswith("on_") and callable(getattr(self, cb))
        }

    def _get_config(self):
        """Return the plugin section from the bot config, plus common values."""
        plugins_configs = self.bot.config["plugins"]
        config = plugins_configs["common"].copy()
        config.update(plugins_configs.get(self.name, {}))
        # Load resources as config values.
        resources_dir = self.bot.config["resources_dir"]
        for key, resource_path in config.get("resources", {}).items():
            resource_path = Path(resources_dir) / resource_path
            try:
                with open(resource_path, "rt") as resource_file:
                    config[key] = [l.strip() for l in resource_file.readlines()]
            except OSError:
                self.bot.log_e(f"Could not load resource at {resource_path}.")
        return config

    def _check_config(self):
        """Return True if the plugin config is properly setup."""
        missing = False
        for key in self.REQUIRED_CONFIGS:
            if key not in self.config:
                self.bot.log_e(f"Missing '{key}' in {self.name} configuration.")
                missing = True
        return not missing

    def get_runtime_value(self, key, default=None, ns=None):
        """Get a value from the plugin runtime dict.

        This will get the value from the plugin namespace, but it is possible to
        get runtime values from other plugins using their name as `ns`.
        """
        if ns is None:
            ns = self.name
        return self.bot.values[ns].get(key, default)

    def set_runtime_value(self, key, value):
        """Set a value in the plugin runtime dict."""
        self.bot.values[self.name][key] = value

    def get_storage_value(self, key, default=None):
        """Get a value from the plugin persistent storage."""
        return self.bot.storage.get(self.name, {}).get(key, default)

    def set_storage_value(self, key, value):
        """Set a value in the plugin persistent storage."""
        if self.name not in self.bot.storage:
            self.bot.storage[self.name] = {key: value}
        else:
            self.bot.storage[self.name][key] = value

    def append_storage_list_value(self, key, value):
        """Append a value to a list in the plugin persistent storage."""
        if self.name not in self.bot.storage:
            self.bot.storage[self.name] = {key: [value]}
        elif key not in self.bot.storage[self.name]:
            self.bot.storage[self.name][key] = [value]
        else:
            self.bot.storage[self.name][key].append(value)

    def remove_storage_list_value(self, key, value):
        if self.name in self.bot.storage and key in self.bot.storage[self.name]:
            self.bot.storage[self.name][key].remove(value)

    def should_answer_question(self, message):
        """Store Question in object and return True if it should answer it."""
        words = message.split()
        if words[0].lower() not in self.bot.names:
            return False
        question = message[len(words[0]):].strip()

        for q in self.config.get("questions", []):
            if question.startswith(q):
                self.question = Question(q, question[len(q):].strip())
                self.bot.log_d(f"Answering question from plugin {self.name}.")
                return True
        return False

    def should_handle_command(self, message, no_content=False):
        """Store Command in object and return True if it should handle it."""
        command = self.parse_command(message, no_content=no_content)
        commands = self.config.get("commands", [])
        if (
            any(command.ident == c for c in commands) or
            (no_content and any(command.ident.startswith(c) for c in commands))
        ):
            self.command = command
            self.bot.log_d(f"Processing command from plugin {self.name}.")
            return True
        return False

    def parse_command(self, message, no_content=False):
        """Return a command ID if this message is a command."""
        words = message.split()
        command_suffix = self.config["command_suffix"]
        if words[0].lower() in self.bot.names and words[-1] == command_suffix:
            if no_content:
                ident = " ".join(words[1:-1])
                content = ""
            else:
                ident = words[1]
                content = " ".join(words[2:-1])
            return Command(ident, content)

    def signal_failure(self, target):
        """Signal a plugin failure to target."""
        self.bot.say(target, self.bot.config["error_message"])


@dataclass
class Question:
    preambule: str
    content: str


@dataclass
class Command:
    ident: str
    content: str