"""Current weather + daily forecast via Open-Meteo (free, no API key)."""

import logging
import time
from datetime import date

import requests
from PIL import Image, ImageDraw

from screens.base import Screen
from screens.render_utils import load_font, text_width
from screens.weather_icons import WMO_CODES, draw_weather_icon

BLACK = (0, 0, 0)
BLUE = (0, 0, 255)
RED = (200, 0, 0)

logger = logging.getLogger(__name__)

HTTP_TIMEOUT = 10
GEOCODE_URL = "https://geocoding-api.open-meteo.com/v1/search"
FORECAST_DAY_CHOICES = (3, 5, 7)

WEEKDAY_ABBR_DE = ["Mo", "Di", "Mi", "Do", "Fr", "Sa", "So"]


class WeatherScreen(Screen):
    id = "weather"
    display_name = "Weather"
    poll_interval = 1800  # fallback default (30 min) if settings has no update_minutes yet

    def default_settings(self) -> dict:
        return {
            "city": "", "latitude": None, "longitude": None, "forecast_days": 3, "update_minutes": 30,
            "show_feels_like": True,
            "show_high_low": True,
            "show_rain_chance": True,
            "show_hourly_graph": True,
        }

    def get_poll_interval(self, settings: dict) -> int:
        raw = settings.get("update_minutes")
        try:
            # `raw or 30` would also catch a legitimate 0 (falsy) and silently
            # replace it with 30 instead of clamping to the 1-minute floor
            # below -- only fall back to the default when it's genuinely unset.
            minutes = int(raw) if raw is not None else 30
        except (TypeError, ValueError):
            minutes = 30
        return max(1, minutes) * 60

    def geocode(self, city: str):
        """Resolve a city name to coordinates via Open-Meteo's free geocoding
        API (no key needed). Returns {"latitude", "longitude", "label"} or
        None if nothing matched."""
        response = requests.get(
            GEOCODE_URL,
            params={"name": city, "count": 1, "language": "de"},
            timeout=HTTP_TIMEOUT,
        )
        response.raise_for_status()
        results = response.json().get("results") or []
        if not results:
            return None

        top = results[0]
        label_parts = [top.get("name"), top.get("admin1"), top.get("country")]
        return {
            "latitude": top["latitude"],
            "longitude": top["longitude"],
            "label": ", ".join(p for p in label_parts if p),
        }

    def check(self, settings: dict):
        lat = settings.get("latitude")
        lon = settings.get("longitude")
        if lat is None or lon is None:
            logger.warning("Weather screen has no latitude/longitude configured")
            return None

        forecast_days = settings.get("forecast_days", 3)
        if forecast_days not in FORECAST_DAY_CHOICES:
            forecast_days = 3

        response = requests.get(
            "https://api.open-meteo.com/v1/forecast",
            params={
                "latitude": lat,
                "longitude": lon,
                # "current" (not the legacy "current_weather=true") is what
                # exposes apparent_temperature. Confirmed live which fields
                # come back plain-local (no Z suffix) under timezone=auto,
                # same as the "daily" block already relied on below.
                "current": "temperature_2m,apparent_temperature,weather_code",
                "daily": "weather_code,temperature_2m_max,temperature_2m_min,precipitation_probability_max",
                "hourly": "temperature_2m",
                "forecast_days": forecast_days,
                "timezone": "auto",
            },
            timeout=HTTP_TIMEOUT,
        )
        response.raise_for_status()
        payload = response.json()

        current = payload.get("current") or {}
        if "temperature_2m" not in current:
            return None

        code = int(current.get("weather_code", -1))
        description, kind = WMO_CODES.get(code, ("Unbekannt", "clear"))

        days = []
        daily = payload.get("daily") or {}
        for i, date_str in enumerate(daily.get("time", [])):
            try:
                weekday = date.fromisoformat(date_str).weekday()
            except ValueError:
                continue
            day_code = int(daily["weather_code"][i])
            _, day_kind = WMO_CODES.get(day_code, ("Unbekannt", "clear"))
            days.append({
                "label": WEEKDAY_ABBR_DE[weekday],
                "kind": day_kind,
                "high": daily["temperature_2m_max"][i],
                "low": daily["temperature_2m_min"][i],
            })

        rain_chance = None
        probs = daily.get("precipitation_probability_max") or []
        if probs and probs[0] is not None:
            rain_chance = int(probs[0])

        # Today's hourly points, for the day-graph -- "hourly" spans all of
        # forecast_days, filtered down to just today's date string prefix.
        today_str = date.today().isoformat()
        hourly = payload.get("hourly") or {}
        hourly_today = [
            {"hour": int(t[11:13]), "temp": temp}
            for t, temp in zip(hourly.get("time", []), hourly.get("temperature_2m", []))
            if t.startswith(today_str)
        ]

        return {
            "temperature": current["temperature_2m"],
            "feels_like": current.get("apparent_temperature"),
            "description": description,
            "kind": kind,
            "days": days,
            "high_today": days[0]["high"] if days else None,
            "low_today": days[0]["low"] if days else None,
            "rain_chance": rain_chance,
            "hourly_today": hourly_today,
        }

    def render(self, state, settings: dict, resolution: tuple[int, int]) -> Image.Image:
        width, height = resolution
        image = Image.new("RGB", (width, height), "white")
        draw = ImageDraw.Draw(image)
        scale = min(width, height)
        pad = width * 0.06

        if not state:
            font = load_font(size=int(scale * 0.06))
            msg = "Kein Standort konfiguriert" if not (
                settings.get("latitude") and settings.get("longitude")
            ) else "Wetterdaten nicht verfügbar"
            mw = text_width(draw, msg, font)
            draw.text(((width - mw) / 2, height / 2), msg, font=font, fill="black")
            return image

        days = state.get("days") or []
        has_forecast = bool(days)
        hourly = state.get("hourly_today") or []
        show_graph = settings.get("show_hourly_graph", True) and len(hourly) >= 2
        lower_sections = int(has_forecast) + int(show_graph)

        # Current conditions: icon on the left, temp/description/extras
        # stacked on the right -- sized from `scale` and measured via actual
        # text bounding boxes so current_h can be *derived* from what the
        # block actually needs, same principle as the original stacked
        # layout, just laid out horizontally now.
        icon_size = scale * 0.34
        temp_font = load_font(size=int(scale * 0.15), bold=True)
        desc_font = load_font(size=int(scale * 0.055))
        extra_font = load_font(size=int(scale * 0.04))

        temp_str = f"{round(state['temperature'])}°"
        desc = state["description"]

        extra_parts = []
        if settings.get("show_feels_like", True) and state.get("feels_like") is not None:
            extra_parts.append(f"Gefühlt {round(state['feels_like'])}°")
        if (
            settings.get("show_high_low", True)
            and state.get("high_today") is not None
            and state.get("low_today") is not None
        ):
            extra_parts.append(f"H {round(state['high_today'])}° L {round(state['low_today'])}°")
        if settings.get("show_rain_chance", True) and state.get("rain_chance") is not None:
            extra_parts.append(f"{state['rain_chance']}% Regen")
        extra_line = " · ".join(extra_parts)

        temp_left, temp_top, temp_right, temp_bottom = draw.textbbox((0, 0), temp_str, font=temp_font)
        temp_h = temp_bottom - temp_top
        desc_left, desc_top, desc_right, desc_bottom = draw.textbbox((0, 0), desc, font=desc_font)
        desc_h = desc_bottom - desc_top
        extra_top = extra_h = 0
        if extra_line:
            extra_left, extra_top, extra_right, extra_bottom = draw.textbbox((0, 0), extra_line, font=extra_font)
            extra_h = extra_bottom - extra_top

        text_gap = temp_h * 0.22
        text_block_h = temp_h + text_gap + desc_h + ((text_gap + extra_h) if extra_line else 0)
        current_h = max(icon_size, text_block_h)
        top_pad = (height - current_h) / 2 if lower_sections == 0 else height * 0.05
        block_top = top_pad

        icon_cx = pad + icon_size / 2
        icon_cy = block_top + current_h / 2
        draw_weather_icon(draw, state["kind"], icon_cx, icon_cy, icon_size)

        text_x = pad + icon_size + scale * 0.05
        text_top = block_top + (current_h - text_block_h) / 2

        draw.text((text_x, text_top - temp_top), temp_str, font=temp_font, fill="black")

        desc_y = text_top + temp_h + text_gap
        draw.text((text_x, desc_y - desc_top), desc, font=desc_font, fill="black")

        if extra_line:
            extra_y = desc_y + desc_h + text_gap
            draw.text((text_x, extra_y - extra_top), extra_line, font=extra_font, fill="black")

        if lower_sections == 0:
            return image

        current_bottom = block_top + current_h + height * 0.045
        remaining_h = height - current_bottom - height * 0.02
        content_w = width - 2 * pad

        if show_graph and has_forecast:
            graph_h = remaining_h * 0.48
            self._draw_hourly_graph(draw, hourly, pad, current_bottom, content_w, graph_h, scale)
            self._draw_daily_forecast(
                draw, days, pad, current_bottom + graph_h + height * 0.015,
                content_w, remaining_h - graph_h - height * 0.015, scale,
            )
        elif show_graph:
            self._draw_hourly_graph(draw, hourly, pad, current_bottom, content_w, remaining_h, scale)
        elif has_forecast:
            self._draw_daily_forecast(draw, days, pad, current_bottom, content_w, remaining_h, scale)

        return image

    def _draw_daily_forecast(self, draw, days, x, y, w, h, scale):
        draw.rectangle((x, y, x + w, y + 2), fill=BLACK)
        content_top = y + h * 0.1
        content_h = h - h * 0.1

        col_w = w / len(days)
        label_font = load_font(size=int(scale * 0.052), bold=True)
        day_temp_font = load_font(size=int(scale * 0.046), bold=True)
        day_icon_size = min(col_w * 0.75, content_h * 0.48)

        for i, day in enumerate(days):
            cx = x + col_w * i + col_w / 2
            yy = content_top

            label = day["label"]
            lw = text_width(draw, label, label_font)
            draw.text((cx - lw / 2, yy), label, font=label_font, fill="black")
            yy += label_font.size * 1.4

            draw_weather_icon(draw, day["kind"], cx, yy + day_icon_size / 2, day_icon_size)
            yy += day_icon_size * 1.1

            temps = f"{round(day['high'])}°/{round(day['low'])}°"
            dtw = text_width(draw, temps, day_temp_font)
            draw.text((cx - dtw / 2, yy), temps, font=day_temp_font, fill="black")

    def _draw_hourly_graph(self, draw, hourly, x, y, w, h, scale):
        """A simple polyline of today's hourly temps -- min/max labeled at
        their points, a red dot marking the current hour, and a handful of
        evenly-spaced hour labels along the bottom."""
        temps = [pt["temp"] for pt in hourly]
        lo, hi = min(temps), max(temps)
        span = max(hi - lo, 1.0)  # avoid a divide-by-zero on a dead-flat day

        point_font = load_font(size=int(scale * 0.032))
        axis_font = load_font(size=int(scale * 0.028))

        top_margin = point_font.size * 1.5
        bottom_margin = axis_font.size * 1.6
        plot_top = y + top_margin
        plot_h = max(1.0, h - top_margin - bottom_margin)

        n = len(hourly)
        step_x = w / (n - 1)

        def point_xy(i):
            px = x + step_x * i
            py = plot_top + plot_h * (1 - (hourly[i]["temp"] - lo) / span)
            return px, py

        points = [point_xy(i) for i in range(n)]
        draw.line(points, fill=BLUE, width=max(2, int(scale * 0.006)), joint="curve")

        def label_point(i):
            # Always above the point, never below -- a below-point label on
            # a trough sitting right at the plot's left/right edge would
            # otherwise land in the same spot as the hour-axis labels.
            px, py = points[i]
            label = f"{round(hourly[i]['temp'])}°"
            lw = text_width(draw, label, point_font)
            ly = py - point_font.size * 1.25
            lx = min(max(px - lw / 2, x), x + w - lw)
            draw.text((lx, ly), label, font=point_font, fill="black")

        max_i = max(range(n), key=lambda i: hourly[i]["temp"])
        min_i = min(range(n), key=lambda i: hourly[i]["temp"])
        label_point(max_i)
        if min_i != max_i:
            label_point(min_i)

        now_hour = time.localtime().tm_hour
        now_i = next((i for i, pt in enumerate(hourly) if pt["hour"] == now_hour), None)
        if now_i is not None:
            px, py = points[now_i]
            r = max(3, int(scale * 0.011))
            draw.ellipse((px - r, py - r, px + r, py + r), fill=RED)

        axis_y = y + h - axis_font.size
        tick_idxs = sorted(set((0, n // 4, n // 2, (3 * n) // 4, n - 1)))
        for i in tick_idxs:
            label = f"{hourly[i]['hour']:02d}"
            lw = text_width(draw, label, axis_font)
            px, _ = points[i]
            lx = min(max(px - lw / 2, x), x + w - lw)
            draw.text((lx, axis_y), label, font=axis_font, fill="black")