from __future__ import annotations

import json
import re
from dataclasses import dataclass
from datetime import datetime, time, timezone
from urllib.parse import urljoin

from bs4 import BeautifulSoup, Tag


class CommunityParseError(ValueError):
    pass


@dataclass(frozen=True, slots=True)
class ExternalCatch:
    source_system: str
    source_external_id: str
    source_url: str
    fish: str
    fish_external_id: str | None
    waterbody: str
    waterbody_external_id: str | None
    x: int | None
    y: int | None
    weight_g: int | None
    bait: str | None
    rig_type: str | None
    game_time: time | None
    published_at: datetime | None
    player_name: str | None
    weather: str | None
    water_temperature_c: float | None
    clip: str | None
    fishing_style: str | None
    evidence_urls: tuple[str, ...]
    coordinate_raw: str | None = None


@dataclass(frozen=True, slots=True)
class EquipmentItem:
    kind: str
    name: str
    external_id: str | None


@dataclass(frozen=True, slots=True)
class RF4DBCatchDetail:
    source_external_id: str
    source_url: str
    wind: str | None
    line_release_m: float | None
    clip_m: float | None
    cast_direction_deg: float | None
    equipment: tuple[EquipmentItem, ...]


@dataclass(frozen=True, slots=True)
class RF4DBWaterbody:
    source_system: str
    source_external_id: str
    source_url: str
    name: str
    unlock_level: int | None
    unlock_label: str
    fish_species_count: int
    image_url: str | None


@dataclass(frozen=True, slots=True)
class RF4DBWaterbodyDetail:
    source_system: str
    source_external_id: str
    source_url: str
    name: str
    description: str | None
    aliases: tuple[str, ...]
    fish_species: tuple[str, ...]
    fish_external_ids: tuple[str | None, ...]
    image_urls: tuple[str, ...]
    point_urls: tuple[str, ...]


def _text(node: Tag | None) -> str:
    return " ".join(node.get_text(" ", strip=True).split()) if node else ""


def _fish_name(node: Tag) -> str:
    """Read a fish label while dropping the optional trophy weight suffix."""
    return re.sub(r"\s*\d+(?:[.,]\d+)?\s*(?:кг|kg|г|g)\s*$", "", _text(node), flags=re.I).strip()


def _key(href: str | None) -> str | None:
    if not href:
        return None
    return href.rstrip("/").rsplit("/", 1)[-1]


def _coordinates(raw: str) -> tuple[int | None, int | None]:
    match = re.fullmatch(r"\s*(-?\d{1,5}):(-?\d{1,5})\s*", raw)
    return (int(match.group(1)), int(match.group(2))) if match else (None, None)


def _game_time(raw: str) -> time | None:
    match = re.search(r"Игровое время\s*(\d{1,2}):(\d{2})", raw)
    return time(int(match.group(1)), int(match.group(2))) if match else None


def _weight(raw: str) -> int | None:
    match = re.search(r"([\d\s.,]+)\s*(кг|kg|г|g)\b", raw.casefold())
    if not match:
        return None
    number, unit = match.groups()
    compact = number.replace(" ", "").replace(",", ".")
    return round(float(compact) * 1000) if unit in {"кг", "kg"} else int(compact.replace(".", ""))


def _next_payloads(html: str) -> list[str]:
    """Decode the string payloads emitted by Next.js' server components."""
    soup = BeautifulSoup(html, "html.parser")
    result: list[str] = []
    pattern = re.compile(r'^self\.__next_f\.push\(\[1,("(?:\\.|[^"\\])*")\]\)$', re.DOTALL)
    for script in soup.find_all("script"):
        raw = script.string or ""
        match = pattern.fullmatch(raw.strip())
        if not match:
            continue
        try:
            result.append(json.loads(match.group(1)))
        except json.JSONDecodeError:
            continue
    return result


def _json_after_marker(
    payloads: list[str], marker: str, *, required_key: str | None = None,
) -> dict[str, object] | None:
    decoder = json.JSONDecoder()
    for payload in payloads:
        offset = 0
        while (start := payload.find(marker, offset)) >= 0:
            offset = start + len(marker)
            try:
                value, _ = decoder.raw_decode(payload[offset:])
            except json.JSONDecodeError:
                continue
            if isinstance(value, dict) and (required_key is None or required_key in value):
                return value
    return None


def _datetime(raw: object) -> datetime | None:
    if not isinstance(raw, str):
        return None
    try:
        return datetime.fromisoformat(raw.replace("Z", "+00:00"))
    except ValueError:
        return None


def parse_rf4db_waterbodies(
    html: str, *, source_url: str = "https://rf4db.com/ru/maps", expected_count: int = 19,
) -> list[RF4DBWaterbody]:
    """Parse the public RF4DB waterbody index without assigning image roles."""
    soup = BeautifulSoup(html, "html.parser")
    result: list[RF4DBWaterbody] = []
    seen: set[str] = set()
    for link in soup.select('a[href*="/ru/maps/level_"]'):
        href = link.get("href")
        if not isinstance(href, str):
            continue
        external_id = _key(href)
        if not external_id or external_id in seen:
            continue
        name = _text(link)
        if not name:
            continue
        card = link.find_parent(["article", "li"])
        if card is None:
            card = link.find_parent("div")
        card_text = _text(card)
        level_match = re.search(r"(?:Уровень|Level)\s*(?:Lv\.?\s*)?(Старт|Start|\d+)", card_text, re.I)
        fish_match = re.search(r"(?:Рыбы|Fish(?:es)?)\s*(\d+)", card_text, re.I)
        if not level_match or not fish_match:
            continue
        unlock_label = level_match.group(1)
        unlock_level = int(unlock_label) if unlock_label.isdigit() else None
        image = card.select_one("img[src], img[data-src]") if card else None
        image_raw = image.get("src") or image.get("data-src") if image else None
        image_url = urljoin(source_url, str(image_raw)) if image_raw else None
        result.append(RF4DBWaterbody(
            source_system="rf4db",
            source_external_id=external_id,
            source_url=urljoin(source_url, href),
            name=name,
            unlock_level=unlock_level,
            unlock_label=unlock_label,
            fish_species_count=int(fish_match.group(1)),
            image_url=image_url,
        ))
        seen.add(external_id)
    if not result:
        raise CommunityParseError("RF4DB waterbody cards not found")
    if len(result) != expected_count:
        raise CommunityParseError(
            f"RF4DB waterbody catalog is incomplete: expected {expected_count}, got {len(result)}"
        )
    return result


def parse_rf4db_waterbody_detail(
    html: str, *, source_url: str,
) -> RF4DBWaterbodyDetail:
    """Parse one RF4DB waterbody page without assigning media or coordinates.

    The detail page is accepted only when its localized heading and fish list
    are present. Images and point links remain source candidates; review and
    canonical crosswalks happen in later pipeline stages.
    """
    soup = BeautifulSoup(html, "html.parser")
    root = soup.select_one("article.waterbody-detail, main[data-waterbody-detail]") or soup
    external_id = _key(source_url)
    name = _text(root.select_one("h1"))
    fish_nodes = root.select(".waterbody-fish a[href], [data-fish-list] a[href], a[href*='/fishes/']")
    if not fish_nodes:
        fish_nodes = root.select(".fish-list a[href], ul.fish a[href]")
    fish_species: list[str] = []
    fish_external_ids: list[str | None] = []
    seen_fish: set[str] = set()
    for node in fish_nodes:
        fish_name = _fish_name(node)
        fish_id = _key(node.get("href"))
        identity = fish_id or fish_name.casefold()
        if not fish_name or identity in seen_fish:
            continue
        fish_species.append(fish_name)
        fish_external_ids.append(fish_id)
        seen_fish.add(identity)
    if not external_id or not name or not fish_species:
        raise CommunityParseError("RF4DB waterbody detail not found or incomplete")

    description_node = root.select_one("[data-description], .waterbody-description, .description")
    description = _text(description_node) or None
    aliases = tuple(dict.fromkeys(
        _text(node) for node in root.select("[data-alias], .waterbody-aliases li, .aliases li")
        if _text(node) and _text(node) != name
    ))
    image_urls = tuple(dict.fromkeys(
        urljoin(source_url, str(node.get("src") or node.get("data-src")))
        for node in root.select("img[src], img[data-src]")
        if (node.get("src") or node.get("data-src"))
        and "/fish/" not in str(node.get("src") or node.get("data-src"))
    ))
    point_urls = tuple(dict.fromkeys(
        urljoin(source_url, str(node.get("href")))
        for node in root.select('a[href*="/spots/"], a[href*="/points/"]')
        if node.get("href")
    ))
    return RF4DBWaterbodyDetail(
        source_system="rf4db", source_external_id=external_id,
        source_url=source_url, name=name, description=description,
        aliases=aliases, fish_species=tuple(fish_species),
        fish_external_ids=tuple(fish_external_ids), image_urls=image_urls,
        point_urls=point_urls,
    )


def parse_rf4db_catches(html: str, *, base_url: str = "https://rf4db.com") -> list[ExternalCatch]:
    soup = BeautifulSoup(html, "html.parser")
    result: list[ExternalCatch] = []
    for card in soup.select("article.catch-card"):
        detail = card.select_one('a.catch-card__time[href*="/catches/"]')
        fish_link = card.select_one("h2 a")
        map_link = card.select_one('.catch-card__place a[href*="/maps/"]')
        if not detail or not fish_link or not map_link:
            continue
        external_id = _key(detail.get("href"))
        if not external_id:
            continue
        coordinate_raw = _text(card.select_one(".catch-card__place b")) or None
        x, y = _coordinates(coordinate_raw or "")
        bait_link = card.select_one('.catch-card__place a[href*="/wiki/baits/"]')
        badges = card.select(".catch-badge")
        weather = next((_text(b.select_one("b")) for b in badges if _text(b).startswith("Погода")), None)
        temperature_text = next((_text(b.select_one("b")) for b in badges if _text(b).startswith("Темп. воды")), "")
        temperature_match = re.search(r"-?\d+(?:[.,]\d+)?", temperature_text)
        rig = card.select_one(".catch-badge--rig")
        result.append(ExternalCatch(
            source_system="rf4db", source_external_id=external_id,
            source_url=urljoin(base_url, str(detail.get("href"))),
            fish=_text(fish_link), fish_external_id=_key(fish_link.get("href")),
            waterbody=_text(map_link), waterbody_external_id=_key(map_link.get("href")),
            x=x, y=y, weight_g=None, bait=_text(bait_link) or None,
            rig_type=_text(rig) or None,
            game_time=_game_time(_text(card.select_one(".catch-card__place"))),
            published_at=None, player_name=None, weather=weather or None,
            water_temperature_c=float(temperature_match.group().replace(",", ".")) if temperature_match else None,
            clip=None, fishing_style=None, evidence_urls=(), coordinate_raw=coordinate_raw,
        ))
    if not result:
        raise CommunityParseError("RF4DB catch cards not found")
    return result


def parse_rf4db_detail(html: str, *, source_url: str) -> RF4DBCatchDetail:
    soup = BeautifulSoup(html, "html.parser")
    root = soup.select_one("article.catch-detail")
    if root is None:
        raise CommunityParseError("RF4DB catch detail not found")
    external_id = _key(source_url)
    if not external_id:
        raise CommunityParseError("RF4DB catch detail URL has no ID")
    facts = {_text(row.select_one("dt")): _text(row.select_one("dd")) for row in root.select(".catch-facts > div")}

    def number(label: str) -> float | None:
        match = re.search(r"-?\d+(?:[.,]\d+)?", facts.get(label, ""))
        return float(match.group().replace(",", ".")) if match else None

    equipment: list[EquipmentItem] = []
    for item in root.select(".catch-equipment article"):
        link = item.select_one("a[href]")
        name = _text(link)
        if not name:
            continue
        equipment.append(EquipmentItem(
            kind=_text(item.select_one("small")) or "Снаряжение",
            name=name,
            external_id=_key(link.get("href")) if link else None,
        ))
    return RF4DBCatchDetail(
        source_external_id=external_id,
        source_url=source_url,
        wind=facts.get("Ветер") or None,
        line_release_m=number("Выпуск лески"),
        clip_m=number("Клипса"),
        cast_direction_deg=number("Направление заброса"),
        equipment=tuple(equipment),
    )


def _rf4stat_date(raw_date: str, raw_time: str, *, now: datetime) -> datetime | None:
    try:
        day, month = (int(part) for part in raw_date.split("."))
        hour, minute = (int(part) for part in raw_time.split(":"))
        value = datetime(now.year, month, day, hour, minute, tzinfo=timezone.utc)
        if value > now:
            value = value.replace(year=value.year - 1)
        return value
    except (TypeError, ValueError):
        return None


def parse_rf4stat_fishing(
    html: str, *, base_url: str = "https://rf4-stat.ru/", now: datetime | None = None,
) -> list[ExternalCatch]:
    soup = BeautifulSoup(html, "html.parser")
    now = now or datetime.now(timezone.utc)
    result: list[ExternalCatch] = []
    for row in soup.select("tr.load-row"):
        id_link = row.select_one('a.share[href^="fishing/"]:not(.hide-print)')
        fish_link = row.select_one('.fish-icon a[href^="fish/"]')
        if not id_link or not fish_link:
            continue
        external_id = _key(id_link.get("href"))
        if not external_id:
            continue
        position = row.select_one(".list-position .position:not(.position-locked)")
        coordinate_raw = _text(row.select_one(".list-position .position")) or None
        x, y = _coordinates(_text(position))
        style = row.select_one(".post-style-icon[title]")
        style_text = str(style.get("title", "")) if style else ""
        result.append(ExternalCatch(
            source_system="rf4stat-fishing", source_external_id=external_id,
            source_url=urljoin(base_url, str(id_link.get("href"))),
            fish=_text(row.select_one("td.fish a")), fish_external_id=_key(fish_link.get("href")),
            waterbody=_text(row.select_one("td.mobile-location")), waterbody_external_id=None,
            x=x, y=y, weight_g=_weight(_text(row.select_one("td.fish small"))),
            bait=_text(row.select_one('[data-filter="bait"]')) or None,
            rig_type=None, game_time=None,
            published_at=_rf4stat_date(_text(row.select_one("td.time small")), _text(row.select_one("td.time > div")), now=now),
            player_name=_text(row.select_one("td.list-gamer a")) or None,
            weather=None, water_temperature_c=None,
            clip=_text(row.select_one(".clip")) or None,
            fishing_style=style_text.removeprefix("Вид ловли:").strip() or None,
            evidence_urls=(urljoin(base_url, str(row.select_one("a.share.hide-print").get("href"))),) if row.select_one("a.share.hide-print") else (),
            coordinate_raw=coordinate_raw,
        ))
    if not result:
        raise CommunityParseError("RF4-STAT fishing rows not found")
    return result


def parse_rf4stat_posts(
    html: str, *, base_url: str = "https://rf4-stat.ru/",
) -> list[ExternalCatch]:
    soup = BeautifulSoup(html, "html.parser")
    result: list[ExternalCatch] = []
    for post in soup.select(".post-item.load-row"):
        post_id = str(post.get("data-post-id", "")).strip()
        if not post_id:
            continue
        published_raw = str(post.get("data-published-at", ""))
        published_at = datetime.fromtimestamp(int(published_raw), tz=timezone.utc) if published_raw.isdigit() else None
        position = post.select_one(".spot-col .position:not(.position-locked)")
        coordinate_raw = _text(post.select_one(".spot-col .position")) or None
        x, y = _coordinates(_text(position))
        style = post.select_one(".post-style-icon[title]")
        style_text = str(style.get("title", "")) if style else ""
        evidence = tuple(urljoin(base_url, str(image.get("src"))) for image in post.select(".screen-file-slot img[src]"))
        baits = _text(post.select_one(".bait-text")) or None
        for index, fish in enumerate(post.select(".fish-icon")):
            fish_link = fish.select_one('a[href^="fish/"]')
            fish_name = _text(fish.select_one(".fish-name"))
            if not fish_name:
                continue
            result.append(ExternalCatch(
                source_system="rf4stat-post", source_external_id=f"{post_id}:{index}",
                source_url=urljoin(base_url, f"posts/{post_id}"),
                fish=fish_name, fish_external_id=_key(fish_link.get("href")) if fish_link else None,
                waterbody=_text(post.select_one(".location")), waterbody_external_id=None,
                x=x, y=y, weight_g=_weight(_text(fish.select_one(".weight"))),
                bait=baits, rig_type=None, game_time=None, published_at=published_at,
                player_name=_text(post.select_one(".player")) or None,
                weather=None, water_temperature_c=None,
                clip=_text(post.select_one(".clip")) or None,
                fishing_style=style_text.removeprefix("Вид ловли:").strip() or None,
                evidence_urls=evidence, coordinate_raw=coordinate_raw,
            ))
    if not result:
        raise CommunityParseError("RF4-STAT posts not found")
    return result


def parse_rf4map_point(html: str, *, source_url: str) -> list[ExternalCatch]:
    soup = BeautifulSoup(html, "html.parser")
    lake_link = soup.select_one('a[href^="/lakes/"]')
    waterbody = _text(lake_link)
    waterbody_id = _key(lake_link.get("href")) if lake_link else None
    points = _json_after_marker(_next_payloads(html), '"points":')
    items = points.get("items") if points else None
    if not waterbody or not waterbody_id or not isinstance(items, list):
        raise CommunityParseError("RF4MAP point payload not found")

    result: list[ExternalCatch] = []
    for item in items:
        if not isinstance(item, dict) or not isinstance(item.get("id"), int):
            continue
        fish = item.get("fish")
        bait = item.get("bait")
        evidence = item.get("imageUrls")
        if not isinstance(fish, dict) or not isinstance(fish.get("name"), str):
            continue
        if not isinstance(evidence, list):
            evidence = []
        result.append(ExternalCatch(
            source_system="rf4map", source_external_id=str(item["id"]), source_url=source_url,
            fish=str(fish["name"]), fish_external_id=str(fish["id"]) if isinstance(fish.get("id"), int) else None,
            waterbody=waterbody, waterbody_external_id=waterbody_id,
            x=item.get("positionX") if isinstance(item.get("positionX"), int) else None,
            y=item.get("positionY") if isinstance(item.get("positionY"), int) else None,
            weight_g=None,
            bait=str(bait["name"]) if isinstance(bait, dict) and isinstance(bait.get("name"), str) else None,
            rig_type=None, game_time=None, published_at=_datetime(item.get("createdAt")),
            player_name=item.get("authorName") if isinstance(item.get("authorName"), str) else None,
            weather=None, water_temperature_c=None,
            clip=str(item["clip"]) if isinstance(item.get("clip"), (int, float)) else None,
            fishing_style=None,
            evidence_urls=tuple(url for url in evidence or [] if isinstance(url, str)),
            coordinate_raw=f"{item['positionX']}:{item['positionY']}" if isinstance(item.get("positionX"), int) and isinstance(item.get("positionY"), int) else None,
        ))
    if not result:
        raise CommunityParseError("RF4MAP point observations not found")
    return result


def parse_rf4posts_spot(html: str, *, source_url: str) -> list[ExternalCatch]:
    soup = BeautifulSoup(html, "html.parser")
    spot = _json_after_marker(_next_payloads(html), '"spot":', required_key="id")
    species = spot.get("fishSpecies") if spot else None
    spot_id = spot.get("id") if spot else None
    if not isinstance(spot_id, str) or not isinstance(species, list) or not species:
        raise CommunityParseError("RF4 Posts spot payload not found")

    waterbody = _text(soup.select_one("h1"))
    fish_list = soup.select_one('[role="list"][aria-label]')
    fish_names = [_text(node) for node in fish_list.select('[role="listitem"]')] if fish_list else []
    if not waterbody or len(fish_names) != len(species):
        raise CommunityParseError("RF4 Posts localized spot labels not found")
    x, y = _coordinates(str(spot.get("coordinates", "")))
    screenshots = spot.get("screenshots")
    if not isinstance(screenshots, list):
        screenshots = []
    evidence = tuple(
        str(item["url"]) for item in screenshots or []
        if isinstance(item, dict) and isinstance(item.get("url"), str)
    )
    result: list[ExternalCatch] = []
    for fish_id, fish_name in zip(species, fish_names, strict=True):
        if not isinstance(fish_id, str):
            continue
        result.append(ExternalCatch(
            source_system="rf4posts-spot", source_external_id=f"{spot_id}:{fish_id}", source_url=source_url,
            fish=fish_name, fish_external_id=fish_id,
            waterbody=waterbody,
            waterbody_external_id=str(spot["waterBody"]) if isinstance(spot.get("waterBody"), str) else None,
            x=x, y=y, weight_g=None, bait=None,
            rig_type=str(spot["bottomRigType"]) if isinstance(spot.get("bottomRigType"), str) else None,
            game_time=None, published_at=_datetime(spot.get("createdAt")), player_name=None,
            weather=None, water_temperature_c=None,
            clip=str(spot["clip"]) if isinstance(spot.get("clip"), (int, float)) else None,
            fishing_style=str(spot["tackleType"]) if isinstance(spot.get("tackleType"), str) else None,
            evidence_urls=evidence, coordinate_raw=str(spot["coordinates"]) if isinstance(spot.get("coordinates"), str) else None,
        ))
    if not result:
        raise CommunityParseError("RF4 Posts fish species not found")
    return result