from __future__ import annotations

from dataclasses import dataclass, field
from pathlib import Path
from typing import Dict, List

from .models import FileState


@dataclass
class FakeFile:
    torrent_hash: str
    torrent_name: str
    file_index: int
    name: str
    size: int
    downloaded: int
    priority: int = 0
    save_path: Path = Path("/downloads")

    def to_state(self) -> FileState:
        downloaded = min(self.downloaded, self.size)
        remaining = max(self.size - downloaded, 0)
        progress = downloaded / self.size if self.size else 1.0
        return FileState(
            torrent_hash=self.torrent_hash,
            torrent_name=self.torrent_name,
            file_index=self.file_index,
            name=self.name,
            size=self.size,
            downloaded=downloaded,
            progress=progress,
            priority=self.priority,
            remaining=remaining,
            save_path=self.save_path,
        )

    def clone(self) -> FakeFile:
        return FakeFile(
            torrent_hash=self.torrent_hash,
            torrent_name=self.torrent_name,
            file_index=self.file_index,
            name=self.name,
            size=self.size,
            downloaded=self.downloaded,
            priority=self.priority,
            save_path=self.save_path,
        )


@dataclass
class FakeTorrent:
    torrent_hash: str
    name: str
    files: List[FakeFile]
    sequential: bool = True


class FakeQBClient:
    """In-memory emulator that mimics the parts of qBittorrent the scheduler needs."""

    def __init__(self, torrents: List[FakeTorrent]):
        self.torrents: Dict[str, FakeTorrent] = {t.torrent_hash: t for t in torrents}
        self.priority_calls: List[Dict] = []
        self.sequential_calls: List[Dict] = []

    def fetch_file_states(self) -> List[FileState]:
        states: List[FileState] = []
        for torrent in self.torrents.values():
            for file in torrent.files:
                states.append(file.to_state())
        return states

    def set_priority(self, torrent_hash: str, file_ids: List[int], priority: int) -> None:
        torrent = self.torrents[torrent_hash]
        for file_id in file_ids:
            for file in torrent.files:
                if file.file_index == file_id:
                    file.priority = priority
                    break
        self.priority_calls.append(
            {"hash": torrent_hash, "file_ids": list(file_ids), "priority": priority}
        )

    def set_sequential(self, torrent_hashes: List[str], value: bool) -> None:
        for torrent_hash in torrent_hashes:
            torrent = self.torrents[torrent_hash]
            torrent.sequential = value
        self.sequential_calls.append({"hashes": list(torrent_hashes), "value": value})