import json
import logging
import uuid
from datetime import datetime, UTC

from yuxi.channel.extensions.minecraft.dedupe import is_duplicate as check_dedup
from yuxi.channel.extensions.minecraft.protocol import (
    read_string,
    read_uuid,
    read_varint,
    read_bool,
    read_varint_at,
    read_string_at,
)
from yuxi.channel.extensions.minecraft.format import strip_mc_format_codes, json_chat_to_plain
from yuxi.channel.extensions.minecraft.types import McPacket, ResolvedMcAccount
from yuxi.channel.message.models import GroupContext, MessageType, PeerInfo, UnifiedMessage
from yuxi.channel.routing.models import PeerKind

logger = logging.getLogger(__name__)


def mc_packet_to_unified(
    packet: McPacket,
    account: ResolvedMcAccount,
) -> UnifiedMessage | None:
    if packet.packet_id == 0x37:
        return _parse_player_chat_1214(packet, account)
    if packet.packet_id == 0x38:
        return _parse_player_chat_1204(packet, account)
    if packet.packet_id in (0x6B, 0x64):
        return _parse_system_chat(packet, account)
    return None


def _parse_player_chat_1214(packet: McPacket, account: ResolvedMcAccount) -> UnifiedMessage | None:
    try:
        offset = 0
        sender_uuid, consumed = read_uuid(packet.data, offset)
        offset += consumed
        msg_index, consumed = read_varint(packet.data, offset)
        offset += consumed
        _sig_present, consumed = read_bool(packet.data, offset)
        offset += consumed
        sender_name_len, consumed = read_varint(packet.data, offset)
        offset += consumed
        sender_name_bytes = packet.data[offset : offset + sender_name_len]
        sender_name = sender_name_bytes.decode("utf-8", errors="replace")
        offset += sender_name_len

        if check_dedup(msg_index):
            return None

        content = _extract_chat_content_1214(packet.data, offset)
        content = strip_mc_format_codes(content).strip()
        if not content:
            return None

        group_id = f"mc:{account.host}:{account.port}"
        bot_username = account.username

        was_mentioned = bot_username.lower() in content.lower() if bot_username else False

        return UnifiedMessage(
            msg_id=f"mc:chat:{msg_index}:{uuid.uuid4().hex[:8]}",
            channel_type="minecraft",
            account_id=account.account_id,
            content=content,
            sender=PeerInfo(
                kind=PeerKind.USER,
                id=sender_uuid,
                display_name=sender_name,
                username=sender_name,
            ),
            message_type=MessageType.TEXT,
            group=GroupContext(
                id=group_id,
                name=account.host,
            ),
            timestamp=datetime.now(UTC),
            raw_payload={
                "sender_uuid": sender_uuid,
                "sender_name": sender_name,
                "message_index": msg_index,
                "world": account.default_dimension,
            },
            metadata={
                "minecraft_server": account.host,
                "minecraft_port": account.port,
                "minecraft_world": account.default_dimension,
                "minecraft_message_index": msg_index,
            },
            surface="minecraft",
            originating_channel="minecraft",
            conversation_label=group_id,
            was_mentioned=was_mentioned,
            explicitly_mentioned_bot=was_mentioned,
        )
    except Exception:
        logger.exception("Failed to parse MC 1.21.4 player chat packet")
        return None


def _parse_player_chat_1204(packet: McPacket, account: ResolvedMcAccount) -> UnifiedMessage | None:
    try:
        offset = 0

        sender_uuid_bytes = packet.data[offset : offset + 16]
        offset += 16
        sender_uuid = str(uuid.UUID(bytes=sender_uuid_bytes))

        index, offset = read_varint_at(packet.data, offset)

        has_signature = bool(packet.data[offset])
        offset += 1
        if has_signature:
            sig_len, offset = read_varint_at(packet.data, offset)
            offset += sig_len

        sender_name, offset = read_string_at(packet.data, offset)

        content = _extract_chat_content_1204_at(packet.data, offset)
        content = strip_mc_format_codes(content).strip()
        if not content:
            return None

        if check_dedup(index):
            return None

        group_id = f"mc:{account.host}:{account.port}"
        bot_username = account.username

        was_mentioned = bot_username.lower() in content.lower() if bot_username else False

        return UnifiedMessage(
            msg_id=f"mc:chat:{index}:{uuid.uuid4().hex[:8]}",
            channel_type="minecraft",
            account_id=account.account_id,
            content=content,
            sender=PeerInfo(
                kind=PeerKind.USER,
                id=sender_uuid,
                display_name=sender_name,
                username=sender_name,
            ),
            message_type=MessageType.TEXT,
            group=GroupContext(
                id=group_id,
                name=account.host,
            ),
            timestamp=datetime.now(UTC),
            raw_payload={
                "sender_uuid": sender_uuid,
                "sender_name": sender_name,
                "message_index": index,
                "world": account.default_dimension,
            },
            metadata={
                "minecraft_server": account.host,
                "minecraft_port": account.port,
                "minecraft_world": account.default_dimension,
                "minecraft_message_index": index,
            },
            surface="minecraft",
            originating_channel="minecraft",
            conversation_label=group_id,
            was_mentioned=was_mentioned,
            explicitly_mentioned_bot=was_mentioned,
        )
    except Exception:
        logger.exception("Failed to parse MC 1.20.4 player chat packet")
        return None


def _parse_system_chat(packet: McPacket, account: ResolvedMcAccount) -> UnifiedMessage | None:
    try:
        content, _ = read_string(packet.data, 0)
        try:
            parsed = json.loads(content)
            plain_text = json_chat_to_plain(parsed)
        except json.JSONDecodeError:
            plain_text = content

        plain_text = strip_mc_format_codes(plain_text).strip()
        if not plain_text:
            return None

        group_id = f"mc:{account.host}:{account.port}"

        return UnifiedMessage(
            msg_id=f"mc:system:{uuid.uuid4().hex}",
            channel_type="minecraft",
            account_id=account.account_id,
            content=plain_text,
            sender=PeerInfo(
                kind=PeerKind.USER,
                id="system",
                display_name="[Minecraft]",
                username="system",
                is_bot=True,
            ),
            message_type=MessageType.EVENT,
            group=GroupContext(
                id=group_id,
                name=account.host,
            ),
            timestamp=datetime.now(UTC),
            metadata={
                "minecraft_server": account.host,
                "minecraft_system_message": True,
            },
            surface="minecraft",
            originating_channel="minecraft",
            conversation_label=group_id,
        )
    except Exception:
        logger.exception("Failed to parse MC system chat packet")
        return None


def _extract_chat_content_1204(data: bytes) -> str:
    content = read_string(data, 0)[0]
    try:
        parsed = json.loads(content)
        return json_chat_to_plain(parsed)
    except (json.JSONDecodeError, TypeError):
        return content


def _extract_chat_content_1204_at(data: bytes, offset: int) -> str:
    content = read_string(data, offset)[0]
    try:
        parsed = json.loads(content)
        return json_chat_to_plain(parsed)
    except (json.JSONDecodeError, TypeError):
        return content


def _extract_chat_content_1214(data: bytes, offset: int) -> str:
    content = read_string(data, offset)[0]
    try:
        parsed = json.loads(content)
        return json_chat_to_plain(parsed)
    except (json.JSONDecodeError, TypeError):
        return content