import difflib

from textual.containers import Horizontal
from textual.css.query import NoMatches
from textual.message import Message
from textual.widget import Widget
from textual.widgets import Button, SelectionList, Static, Switch, TextArea


class MultiAgentSelector(Widget):
    class AgentsSelected(Message):
        def __init__(self, selected_agents):
            super().__init__()
            self.selected_agents = selected_agents

    def __init__(self, all_agents: list[dict]):
        super().__init__()
        self.all_agents = all_agents
        self._match_type = "fuzzy"

    @property
    def match_type(self):
        return self._match_type

    @match_type.setter
    def match_type(self, value):
        self._match_type = value

    def compose(self):
        yield Static("🔍 Multi-Agent Selector", id="selector_title")
        text_area = TextArea(
            id="device_input",
            placeholder="Paste device names here (one per line)",
        )
        text_area.styles.height = 10
        text_area.styles.overflow_y = "auto"
        yield text_area

        with Horizontal() as switch_container:
            switch_container.styles.height = "auto"
            switch_container.styles.align = ("left", "middle")
            switch_label = Static("Match Type: Fuzzy", id="match_switch_label")
            switch_label.styles.width = "auto"
            switch_label.styles.padding = (0, 1)
            yield switch_label

            switch = Switch(value=False, id="match_switch")
            switch.styles.width = "auto"
            yield switch

        yield Button("Search", id="search_button")

        yield SelectionList(id="match_results")
        yield Static(id="unmatched_label")

        yield Horizontal(
            Button("Select All", id="select_all"),
            Button("Select None", id="select_none"),
        )

        yield Button("Continue with Selected", id="submit_selection", variant="primary")

    def on_switch_changed(self, event: Switch.Changed):
        self.match_type = "exact" if event.value else "fuzzy"
        self.query_one("#match_switch_label", Static).update(
            f"Match Type: {self.match_type.capitalize()}"
        )

    def on_button_pressed(self, event: Button.Pressed):
        btn_id = event.button.id  # can be None for internal buttons

        # Only query when needed
        try:
            match_list = self.query_one("#match_results", SelectionList)
        except NoMatches:
            # UI not mounted yet or id changed—just ignore gracefully
            return

        if btn_id == "select_all":
            match_list.select_all()
            event.stop()
        elif btn_id == "select_none":
            match_list.deselect_all()
            event.stop()
        elif btn_id == "submit_selection":
            selected = list(match_list.selected)
            self.post_message(self.AgentsSelected(selected))
            event.stop()
        elif btn_id == "search_button":
            self.update_matches()
            event.stop()

    def update_matches(self):
        raw_input = self.query_one("#device_input", TextArea).text.strip()
        device_names = [line.strip() for line in raw_input.split("\n") if line.strip()]
        matched, unmatched = self.match_devices(device_names)
        match_list = self.query_one("#match_results", SelectionList)
        match_list.clear_options()
        for name in matched:
            match_list.add_option((name, name))
        unmatched_label = self.query_one("#unmatched_label", Static)
        if unmatched:
            unmatched_label.update(f"⚠️ No matches for: {', '.join(unmatched)}")
        else:
            unmatched_label.update("")

    def match_devices(self, device_names: list[str]) -> tuple[list[str], list[str]]:
        if not self.all_agents or not device_names:
            return [], device_names
        agent_names = [agent["hostname"] for agent in self.all_agents]
        matched = set()
        unmatched = []
        for name in device_names:
            if self.match_type == "exact":
                # Case-insensitive exact match
                name_lower = name.lower()
                exact_match = None
                for agent_name in agent_names:
                    if agent_name.lower() == name_lower:
                        exact_match = agent_name
                        break
                if exact_match:
                    matched.add(exact_match)
                else:
                    unmatched.append(name)
            else:
                # Fuzzy match
                matches = difflib.get_close_matches(name, agent_names, n=5, cutoff=0.5)
                if matches:
                    matched.update(matches)
                else:
                    unmatched.append(name)
        return sorted(matched), unmatched