#!/usr/bin/env python3
import os
import pathlib
import re
import subprocess
from enum import Enum, unique

import click
import yaml

try:
    from latex2mathml.converter import convert as latex_to_mathml
except ImportError:
    latex_to_mathml = None

__version__ = "2.0.0"  # new version

CFG_PATH = pathlib.Path("./config.yml")
STATE_PATH = pathlib.Path("./state.yml")

TC_DIR = pathlib.Path("./_testcases")
TEMPLATES_DIR = pathlib.Path("./templates")
SRC_SPACE_DIR = pathlib.Path("./space")
STORAGE_DIR = pathlib.Path("./storage")
BUILD_DIR = pathlib.Path("./build")


# ======
# Helper Functions
# ======


def _natural_sort_key(s: str):
    """Natural sort key: splits string into text/number chunks for proper ordering."""
    return [int(c) if c.isdigit() else c.lower() for c in re.split(r"(\d+)", s)]


def _parse_range_string(range_str: str) -> list[int]:
    """
    범위 문자열을 정수 리스트로 변환.
    * ..N: 1부터 N까지
    * M..N: M부터 N까지
    * N: 단일 숫자
    """
    if range_str.startswith(".."):
        end_str = range_str[2:]
        if not end_str.isdigit():
            raise ValueError("Invalid range format")
        return list(range(1, int(end_str) + 1))

    parts = range_str.split("..")
    if len(parts) == 1:
        if not parts[0].isdigit():
            raise ValueError("Invalid range format")
        return [int(parts[0])]
    elif len(parts) == 2:
        if not parts[0].isdigit() or not parts[1].isdigit():
            raise ValueError("Invalid range format")
        return list(range(int(parts[0]), int(parts[1]) + 1))
    else:
        raise ValueError("Invalid range format")


def _parse_range_string_list(str_list: list[str]) -> list[int]:
    """
    여러 범위 문자열을 정수 리스트로 변환하는 함수; 이때 중복은 제거함.
        * e.g. ["1..3", "5", "7..9"] -> [1, 2, 3, 5, 7, 8, 9]
    """
    result = set()
    for s in str_list:
        result.update(_parse_range_string(s))
    return list(result)


@unique
class Language(Enum):
    """
    실행 가능한 언어(Language)를 정의하는 클래스입니다. 각 언어는 고유 문자열 값을 가짐.
    - Python: py
    - C: c
    - C++: cpp
    - Rust: rs
    - Kotlin: kt
    - Lua: lua
    """

    PYTHON = "py"
    C = "c"
    CPP = "cpp"
    RUST = "rs"
    KOTLIN = "kt"
    LUA = "lua"

    UNDEFINED = "undefined"

    @property
    def build_command(self):
        """
        각 언어에 대한 빌드 명령어.
        """
        return {
            Language.PYTHON: [
                "python",
                "./make.py",
                "build",
            ],
            Language.C: [
                "make",
                "build",
            ],
            Language.CPP: [
                "make",
                "build",
            ],
            Language.RUST: [
                "make",
                "build",
            ],
            Language.KOTLIN: [
                "./gradlew",
                "jar",
            ],
            Language.LUA: [
                "make",
                "build",
            ],
        }[self]

    @property
    def working_dir(self):
        """
        각 언어의 작업 디렉토리
        """
        return f"{SRC_SPACE_DIR}/src-{self.value}"

    @property
    def build_executable(self):
        """
        각 언어의 빌드 후 생성되는 실행 파일의 이름.
        """
        return {
            Language.PYTHON: "py.pyc",
            Language.C: "c.out",
            Language.CPP: "cpp.out",
            Language.RUST: "rs.out",
            Language.KOTLIN: "kt.jar",
            Language.LUA: "lua.luac",
        }[self]

    @property
    def executable_command(self):
        """
        각 언어에 대한 실행 명령어.
        """
        return {
            Language.PYTHON: ["python", f"{BUILD_DIR}/{self.build_executable}"],
            Language.C: [f"{BUILD_DIR}/{self.build_executable}"],
            Language.CPP: [f"{BUILD_DIR}/{self.build_executable}"],
            Language.RUST: [f"{BUILD_DIR}/{self.build_executable}"],
            Language.KOTLIN: ["java", "-jar", f"{BUILD_DIR}/{self.build_executable}"],
            Language.LUA: ["lua", f"{BUILD_DIR}/{self.build_executable}"],
        }[self]

    @staticmethod
    def convert_ext(ext: str):
        """
        확장자를 언어 Enum으로 변환하는 메소드.
        만약 확장자가 정의된 언어에 해당하지 않으면 UNDEFINED를 반환.
        """
        match ext:
            case "py":
                return Language.PYTHON
            case "c":
                return Language.C
            case "cpp":
                return Language.CPP
            case "rs":
                return Language.RUST
            case "kt":
                return Language.KOTLIN
            case "lua":
                return Language.LUA
            case _:
                return Language.UNDEFINED

    @staticmethod
    def convert_name(format_name: str):
        """
        다양한 언어 형식 이름을 언어 Enum으로 변환하는 메소드.
        convert_ext의 Super Set임.
        """
        if Language.convert_ext(format_name) is not Language.UNDEFINED:
            return Language.convert_ext(format_name)
        match format_name.lower():
            case "py" | "py3" | "python" | "python3":
                return Language.PYTHON
            case "c":
                return Language.C
            case "cpp" | "c++":
                return Language.CPP
            case "rust" | "rs":
                return Language.RUST
            case "kt" | "kotlin":
                return Language.KOTLIN
            case "lua":
                return Language.LUA
            case _:
                return Language.UNDEFINED


def _dispatch_target(target: str) -> tuple[str, str, Language]:
    splited = target.split("/")
    if len(splited) != 2:
        raise ValueError(
            "Invalid target format. Expected format: <loc>/<problem>.<lang>"
        )

    prob_parts = splited[1].rsplit(".", 1)
    if len(prob_parts) != 2:
        raise ValueError(
            "Invalid target format. Expected format: <loc>/<problem>.<lang>"
        )

    prob_name, ext = prob_parts
    lang = Language.convert_ext(ext)
    if lang is Language.UNDEFINED:
        raise ValueError(f"Unknown language: {ext}")

    return splited[0], prob_name, lang


class StateManager:
    _instance: "StateManager | None" = None
    _state: dict | None = None

    def __new__(cls) -> "StateManager":
        if cls._instance is None:
            cls._instance = super().__new__(cls)
        return cls._instance

    def _load(self) -> dict:
        if self._state is not None:
            return self._state
        try:
            with open(STATE_PATH, "r", encoding="utf-8") as f:
                self._state = yaml.safe_load(f) or {}
        except FileNotFoundError as exc:
            raise click.ClickException(f"state.yml not found at {STATE_PATH}") from exc
        except yaml.YAMLError as e:
            raise click.ClickException(f"state.yml parse error: {e}") from e
        return self._state  # type: ignore[return-value]

    def save(self) -> None:
        if self._state is None:
            return
        with open(STATE_PATH, "w", encoding="utf-8") as f:
            yaml.safe_dump(self._state, f)

    def check_space(self, lang: Language) -> bool:
        state = self._load()
        return lang.value in state.get("space", {}) and bool(state["space"][lang.value])

    def get_space(self, lang: Language) -> dict:
        state = self._load()
        if not self.check_space(lang):
            raise ValueError(f"No space found for language: {lang}")
        return state["space"][lang.value]

    def add_space(
        self, lang: Language, file: str, location: str, is_completed: bool
    ) -> None:
        state = self._load()
        if "space" not in state:
            state["space"] = {}
        state["space"][lang.value] = {
            "file": file,
            "location": location,
            "is_completed": is_completed,
        }
        self._state = state

    def remove_space(self, lang: Language) -> None:
        state = self._load()
        if "space" in state and lang.value in state["space"]:
            state["space"][lang.value] = {}
            self._state = state

    def clear_space(self, lang: Language) -> None:
        state = self._load()
        if "space" in state and lang.value in state["space"]:
            del state["space"][lang.value]
            self._state = state

    def reload(self) -> None:
        self._state = None


class StorageManager:
    _instance: "StorageManager | None" = None

    def __new__(cls) -> "StorageManager":
        if cls._instance is None:
            cls._instance = super().__new__(cls)
        return cls._instance

    def register_location(self, location: str) -> None:
        path = STORAGE_DIR / location
        os.makedirs(path, exist_ok=True)

    def check_location(self, location: str) -> bool:
        path = STORAGE_DIR / location
        return os.path.isdir(path)

    def register_location_lang(self, location: str, lang: Language) -> None:
        path = STORAGE_DIR / location / lang.value
        os.makedirs(path, exist_ok=True)

    def check_location_lang(self, location: str, lang: Language) -> bool:
        path = STORAGE_DIR / location / lang.value
        return os.path.isdir(path)

    def check_get_file(
        self, location: str, lang: Language, filename: str
    ) -> pathlib.Path | None:
        completed_path = (
            STORAGE_DIR
            / location
            / lang.value
            / "completed"
            / f"{filename}.{lang.value}"
        )
        uncompleted_path = (
            STORAGE_DIR / location / lang.value / f"{filename}.{lang.value}"
        )

        if os.path.isfile(completed_path):
            return completed_path
        elif os.path.isfile(uncompleted_path):
            return uncompleted_path
        else:
            return None

    def save_file(
        self, location: str, lang: Language, filename: str, content: bytes, completed: bool
    ) -> None:
        path = STORAGE_DIR / location / lang.value / ("completed" if completed else "")
        os.makedirs(path, exist_ok=True)
        with open(f"{path}/{filename}", "wb") as f:
            f.write(content)

    def read_file(self, location: str, lang: Language, filename: str) -> bytes:
        path = self.check_get_file(location, lang, filename)
        if path is None:
            raise FileNotFoundError(
                f"File not found in storage: {location}/{filename}.{lang.value}"
            )
        file_path = f"{path}/{filename}"
        if not os.path.isfile(file_path):
            raise FileNotFoundError(f"File not found in storage: {file_path}")
        with open(file_path, "rb") as f:
            return f.read()

    def mark_completed(self, location: str, lang: Language, filename: str) -> None:
        uncompleted_file = (
            STORAGE_DIR / location / lang.value / f"{filename}.{lang.value}"
        )
        completed_file = (
            STORAGE_DIR
            / location
            / lang.value
            / "completed"
            / f"{filename}.{lang.value}"
        )

        os.makedirs(completed_file.parent, exist_ok=True)
        if os.path.isfile(uncompleted_file):
            os.rename(uncompleted_file, completed_file)

    def unmark_completed(self, location: str, lang: Language, filename: str) -> None:
        uncompleted_file = (
            STORAGE_DIR / location / lang.value / f"{filename}.{lang.value}"
        )
        completed_file = (
            STORAGE_DIR
            / location
            / lang.value
            / "completed"
            / f"{filename}.{lang.value}"
        )

        os.makedirs(uncompleted_file.parent, exist_ok=True)
        if os.path.isfile(completed_file):
            os.rename(completed_file, uncompleted_file)


# =======================
# MAIN CLI LOGIC
# =======================


@click.group()
def cli():
    pass


@click.command(name="register")
@click.argument("location", type=str, nargs=1, required=True)
def register(location: str):
    """
    새로운 location을 storage에 등록하는 명령어.
    """
    storage_manager = StorageManager()
    if storage_manager.check_location(location):
        click.secho(
            f"Location '{location}' is already registered.", fg="yellow", bold=True
        )
    else:
        storage_manager.register_location(location)
        click.secho(
            f"Location '{location}' registered successfully.", fg="cyan", bold=True
        )


@click.command(name="create")
@click.argument("target", type=str, nargs=1, required=True)
@click.option(
    "--completed/--no-completed", "-c/-nc", default=False, help="Mark as completed"
)
@click.option(
    "--no-template",
    "-nt",
    is_flag=True,
    help="Do not use template content (create empty file instead)",
)
@click.option(
    "--force", "-f", is_flag=True, help="Overwrite existing file if it already exists"
)
def create(target: str, completed: bool, template: bool, force: bool):
    """
    지정된 location을 storage에 생성하는 명령어
    """
    loc, prob, lang = _dispatch_target(target)

    if not StorageManager().check_location(loc):
        raise click.ClickException(
            f"Location '{loc}' is not registered. Please register it first."
        )

    filename = prob
    existing = StorageManager().check_get_file(loc, lang, filename)
    if existing:
        click.secho(
            f"File '{filename}.{lang.value}' already exists in location '{loc}'",
            fg="yellow",
            bold=True,
        )
        if not force:
            return

    if not template:
        content = b""
    else:
        template_path = TEMPLATES_DIR / f"{lang.value}.txt"
        if template_path.is_file():
            content = template_path.read_bytes()
            click.secho(f"Using template: {template_path}", fg="cyan")
        else:
            content = b""
            click.secho(f"Template not found: {template_path}", fg="yellow")

    StorageManager().save_file(
        loc, lang, f"{filename}.{lang.value}", content, completed
    )
    click.secho(
        f"Created '{filename}.{lang.value}' in location '{loc}'",
        fg="cyan",
        bold=True,
    )


@click.command(name="run")
@click.argument("lang", type=str, nargs=1, required=True)
@click.option("--testcase", "-t", default=["1"], multiple=True)
@click.option("--verbose/--no-verbose", "-v/-nv", default=True)
def run(lang: str, testcase: list[str], verbose: bool):
    """
    지정된 언어로 빌드 및 실행하는 명령어
    """

    # Language 확인
    target_language: Language = Language.convert_name(lang)

    if target_language is Language.UNDEFINED:
        raise click.ClickException("Undefined Language Exception")

    # load된 state가 있는지 확인
    if not StateManager().check_space(target_language):
        raise click.ClickException(
            f"No loaded file for language '{target_language.value}'. Please load a file first."
        )

    # 테케 분석
    tcs: list[int] = _parse_range_string_list(testcase)

    # build
    try:
        s = subprocess.run(
            target_language.build_command,
            check=True,
            capture_output=True,
            text=True,
            cwd=target_language.working_dir,
        )
        print(s.stderr)

    except subprocess.CalledProcessError as e:
        click.secho(">>>>>> [BUILD TIME ERROR] >>>>>>", fg="red", bold=True)
        raise click.ClickException(e.stderr)

    # execution for each test case
    for tc in tcs:
        if not (
            os.path.isfile(f"{TC_DIR}/{tc}.in") and os.path.isfile(f"{TC_DIR}/{tc}.out")
        ):
            click.echo(f"{tc:02d}: {None}")
        else:
            f_in_path = f"{TC_DIR}/{tc}.in"
            f_out_path = f"{TC_DIR}/{tc}.out"

            with (
                open(f_in_path, "r", encoding="utf-8") as f_in,
                open(f_out_path, "r", encoding="utf-8") as f_out,
            ):
                expected = f_out.read().strip()

            proc = subprocess.Popen(
                target_language.executable_command,
                stdin=f_in,
                stdout=subprocess.PIPE,
                stderr=subprocess.PIPE,
                text=True,
            )

            if not verbose:
                for line in proc.stdout:  # type: ignore
                    print(line, end="")

            stdout, stderr = proc.communicate()

            if proc.returncode != 0:
                click.secho(">>>>>> [RUN TIME ERROR] >>>>>>", fg="red", bold=True)
                click.secho(f"{stderr}", fg="red")
                click.secho(f"returncode: {proc.returncode}", fg="red")
                continue

            flag = stdout.strip() == expected
            symbol = (
                click.style("✓", fg="green") if flag else click.style("✗", fg="red")
            )
            click.echo(f"{tc:02d}: {symbol}")

            if verbose:
                click.secho("===" * 3, fg="bright_black")
                click.secho(f"[INPUT]", fg="cyan", bold=True)
                with open(f_in_path, "r") as f:
                    click.echo(f.read())
                click.secho(f"[ACTUAL]", fg="cyan", bold=True)
                click.echo(stdout.strip() if stdout else "(empty)")
                click.secho("===" * 3, fg="bright_black")


@click.command(name="load")
@click.argument("target", type=str, nargs=1, required=True)
@click.option("--force", "-f", is_flag=True)
def load(target: str, force: bool):
    """
    Storage의 파일을 각 언어의 src-space로 이동시키는 명령.
    - force는 src-space에 이미 파일이 존재할 때, 덮어쓸지 결정
    """

    # 파일의 src-space가 어딘지 확인
    loc, prob, lang = _dispatch_target(target)

    if StateManager().check_space(lang):
        if not force:
            raise click.ClickException(
                f"Space for language '{lang.value}' is already occupied."
            )

    path = StorageManager().check_get_file(loc, lang, prob)

    if path is None:
        raise click.ClickException(
            f"File '{prob}.{lang.value}' not found in location '{loc}'. Use 'create' command to create it first."
        )

    dest_path = SRC_SPACE_DIR / f"src-{lang.value}" / "src" / f"main.{lang.value}"

    with open(path, "rb") as f_src, open(dest_path, "wb") as f_dst:
        f_dst.write(f_src.read())
    StateManager().remove_space(lang)
    StateManager().add_space(lang, prob, loc, False)
    click.secho(
        f"Loaded '{prob}.{lang.value}' from location '{loc}' to src-space.",
        fg="cyan",
        bold=True,
    )


@click.command(name="export")
@click.option("--from", "from_", type=str, required=True)
@click.option(
    "--completed/--no-completed", "-c/-nc", is_flag=True, flag_value=False, default=None
)
@click.option("--copy", is_flag=True, help="is copy from state or move")
def export(from_: str, completed: bool, copy: bool):
    # Language 알기
    from_language = Language.convert_name(from_)

    if from_language is Language.UNDEFINED:
        raise click.ClickException("Undefined Language Exception")
    try:
        with open("state.yml", "r", encoding="utf-8") as f:
            state = yaml.safe_load(f)
    except FileNotFoundError as e:
        raise click.ClickException(e)
    except yaml.YAMLError as e:
        raise click.ClickException(e)

    if "space" not in state:
        raise click.ClickException("State(state.yml) Exception")
    elif not state["space"]:
        click.secho("state.space has no member", fg="yellow", bold=True)
        state["space"] = {}

    lang_space_state: dict | None
    if from_language.value not in state["space"]:
        lang_space_state = None
    else:
        lang_space_state = state["space"][from_language.value]

    if lang_space_state is None or not lang_space_state:
        raise click.ClickException("Export Exception: There are no pre-defined state")

    s_file = lang_space_state["file"]
    s_loc = lang_space_state["location"]
    s_is_completed = lang_space_state["is_completed"]

    if not s_file:
        raise click.ClickException(
            f"Export Exception: There is no file in {from_language.value} space"
        )

    if not s_loc:
        raise click.ClickException(f"Export Exception: Location {s_loc} is not defined")

    if completed:
        s_is_completed = True

    dest_path: str = f"{STORAGE_DIR}/{s_loc}/{from_language.value}{'/completed' if s_is_completed else ''}/{s_file}.{from_language.value}"
    source_path: str = (
        f"{SRC_SPACE_DIR}/src-{from_language.value}/src/main.{from_language.value}"
    )

    os.makedirs(os.path.dirname(dest_path), exist_ok=True)

    with open(source_path, "rb") as f_src, open(dest_path, "wb") as f_dst:
        f_dst.write(f_src.read())

    click.echo(f"File {s_file}.{from_language.value} successfully ")

    if not copy:
        with open("state.yml", "w", encoding="utf-8") as f:
            state["space"][from_language.value] = {}
            yaml.safe_dump(state, f)

        os.remove(source_path)


@click.command(name="state")
def state():
    try:
        with open(STATE_PATH, "r", encoding="utf-8") as f_state:
            state = yaml.safe_load(f_state)
    except FileNotFoundError as e:
        raise click.ClickException(e)
    except yaml.YAMLError as e:
        raise click.ClickException(e)

    if "space" not in state:
        raise click.ClickException("state.yml is wrong")
    elif not state["space"]:
        click.secho("state.space has no member", fg="yellow", bold=True)
        state["space"] = {}

    active = sum(1 for v in state["space"].values() if v)
    total = len(state["space"])
    click.secho(f"Space: {active}/{total} active", fg="cyan", bold=True)
    click.echo()

    for k, v in state["space"].items():
        click.secho(f"  {k}/", fg="yellow")
        if not v:
            click.echo(f"    {click.style('—', fg='bright_black')} empty")
        else:
            status = (
                click.style("✓", fg="green")
                if v["is_completed"]
                else click.style("○", fg="white")
            )
            click.echo(f"    {status} {v['file']}.{k} @ {v['location']}")


@click.command(name="init")
@click.argument("count", type=int)
def init(count: int):
    """
    init testcases with initial count and state.yml and config.yml
    """
    if count < 1:
        raise click.UsageError("var count should be greater than 1.")

    if not os.path.exists("./" + TC_DIR):
        os.mkdir(TC_DIR)
    for i in range(1, count + 1):
        default_in_path = "./" + TC_DIR + f"/{i}.in"
        default_out_path = "./" + TC_DIR + f"/{i}.out"
        if not os.path.exists(default_in_path):
            with open(default_in_path, "w", encoding="utf-8") as _:
                pass
        if not os.path.exists(default_out_path):
            with open(default_out_path, "w", encoding="utf-8") as _:
                pass

    click.echo(f"1. Testcases was made with count {count} successfully!")

    if not os.path.isfile("./state.yml"):
        click.echo("2-1. state.yml does not exist, creating...")
        with open("state.yml", "w", encoding="utf-8") as f:
            f.write("space:\n")
        click.echo("2-1. state.yml is created successfully!")
    else:
        click.echo("2-1. state.yml exists")
    if not os.path.isfile("./config.yml"):
        click.echo("2-2. config.yml does not exist, creating...")
        with open("config.yml", "w", encoding="utf-8") as f:
            f.write("space:\n")
        click.echo("2-2. config.yml is created successfully!")
    else:
        click.echo("2-2. config.yml exists")


@click.command(name="show")
@click.argument("filter", type=str, default=None, required=False)
@click.option(
    "--completed/--no-completed",
    "-c/-nc",
    default=False,
    help="Filter by completed status (default: uncompleted only)",
)
@click.option(
    "--all",
    "show_all",
    is_flag=True,
    default=False,
    help="Show all problems regardless of completed status",
)
def show(filter: str | None, completed: bool, show_all: bool):
    """
    Show all stored problems in storage directory.

    \b
    FILTER format (optional):
      location        e.g. zeta
      location/lang   e.g. zeta/rs
      /lang           e.g. /py
    """
    location = None
    lang = None
    if filter:
        parts = filter.split("/", 1)
        if len(parts) == 2:
            location = parts[0] or None
            lang = parts[1] or None
        else:
            location = parts[0]

    storage = pathlib.Path(STORAGE_DIR)
    if not storage.is_dir():
        raise click.ClickException(f"Storage directory '{STORAGE_DIR}' not found")

    # Collect all files
    entries = []  # (location, language, filename, is_completed)

    for loc_dir in sorted(storage.iterdir()):
        if not loc_dir.is_dir():
            continue
        loc_name = loc_dir.name

        if location and loc_name != location:
            continue

        for lang_dir in sorted(loc_dir.iterdir()):
            if not lang_dir.is_dir():
                continue
            lang_name = lang_dir.name

            if (
                lang
                and lang_name != Language.convert_name(lang).value
                and lang_name != lang
            ):
                continue

            # uncompleted files
            for f in sorted(
                lang_dir.iterdir(), key=lambda p: _natural_sort_key(p.stem)
            ):
                if f.is_file():
                    entries.append((loc_name, lang_name, f.stem, False))

            # completed files
            completed_dir = lang_dir / "completed"
            if completed_dir.is_dir():
                for f in sorted(
                    completed_dir.iterdir(), key=lambda p: _natural_sort_key(p.stem)
                ):
                    if f.is_file():
                        entries.append((loc_name, lang_name, f.stem, True))

    # Filter by completed status
    if not show_all:
        entries = [e for e in entries if e[3] == completed]

    if not entries:
        click.echo("No problems found.")
        return

    # Display
    total = len(entries)
    completed_count = sum(1 for e in entries if e[3])
    uncompleted_count = total - completed_count

    click.secho(
        f"Total: {total} (completed: {completed_count}, uncompleted: {uncompleted_count})",
        fg="cyan",
        bold=True,
    )
    click.echo()

    # Group by location
    current_loc = None
    current_lang = None
    for loc_name, lang_name, file_name, is_completed in entries:
        if loc_name != current_loc:
            current_loc = loc_name
            current_lang = None
            click.secho(f"[{loc_name}]", fg="green", bold=True)

        if lang_name != current_lang:
            current_lang = lang_name
            click.secho(f"  {lang_name}/", fg="yellow")

        status = (
            click.style("✓", fg="green")
            if is_completed
            else click.style("○", fg="white")
        )
        click.echo(f"    {status} {file_name}.{lang_name}")


@click.command(name="find")
@click.argument("keyword", type=str)
@click.option(
    "--completed/--no-completed",
    "-c/-nc",
    default=None,
    help="Filter by completed status (default: all)",
)
def find(keyword: str, completed: bool | None):
    """
    Find problems by keyword in storage.

    KEYWORD format:
      keyword              e.g. 2447
      keyword.ext          e.g. 2447.py  (filters by language)
      .ext                 e.g. .py      (all files of a language)
      location/keyword     e.g. zeta/2447
      location/keyword.ext e.g. zeta/2447.py
      location/.ext        e.g. zeta/.py
    """
    location = None
    lang = None
    if "/" in keyword:
        parts = keyword.split("/", 1)
        location = parts[0] or None
        keyword = parts[1]

    # Extract language from extension
    if "." in keyword:
        keyword_base, ext = keyword.rsplit(".", 1)
        lang_candidate = Language.convert_ext(ext)
        if lang_candidate is not Language.UNDEFINED:
            lang = lang_candidate.value
        else:
            keyword_base = keyword
    else:
        keyword_base = keyword

    storage = pathlib.Path(STORAGE_DIR)
    if not storage.is_dir():
        raise click.ClickException(f"Storage directory '{STORAGE_DIR}' not found")

    entries = []  # (location, language, filename, is_completed)

    for loc_dir in sorted(storage.iterdir()):
        if not loc_dir.is_dir():
            continue
        loc_name = loc_dir.name

        if location and loc_name != location:
            continue

        for lang_dir in sorted(loc_dir.iterdir()):
            if not lang_dir.is_dir():
                continue
            lang_name = lang_dir.name

            if lang and lang_name != lang:
                continue

            for f in lang_dir.iterdir():
                if f.is_file() and keyword_base.lower() in f.stem.lower():
                    entries.append((loc_name, lang_name, f.stem, False))

            completed_dir = lang_dir / "completed"
            if completed_dir.is_dir():
                for f in completed_dir.iterdir():
                    if f.is_file() and keyword_base.lower() in f.stem.lower():
                        entries.append((loc_name, lang_name, f.stem, True))

    if completed is not None:
        entries = [e for e in entries if e[3] == completed]

    entries.sort(key=lambda e: (e[0], e[1], _natural_sort_key(e[2])))

    if not entries:
        click.echo("No problems found.")
        return

    total = len(entries)
    completed_count = sum(1 for e in entries if e[3])
    uncompleted_count = total - completed_count

    click.secho(
        f"Found: {total} (completed: {completed_count}, uncompleted: {uncompleted_count})",
        fg="cyan",
        bold=True,
    )
    click.echo()

    current_loc = None
    current_lang = None
    for loc_name, lang_name, file_name, is_completed in entries:
        if loc_name != current_loc:
            current_loc = loc_name
            current_lang = None
            click.secho(f"[{loc_name}]", fg="green", bold=True)

        if lang_name != current_lang:
            current_lang = lang_name
            click.secho(f"  {lang_name}/", fg="yellow")

        status = (
            click.style("✓", fg="green")
            if is_completed
            else click.style("○", fg="white")
        )
        click.echo(f"    {status} {file_name}.{lang_name}")


@click.command(name="fetchprob")
@click.argument("target", type=str, nargs=1, required=True)
@click.option("--force", "-f", is_flag=True, help="Overwrite existing HTML files")
def fetchprob(target: str, force: bool):
    """(disabled) Fetch BOJ problem HTML - BOJ is closing, keeping for future multi-location support."""
    del target, force
    raise click.ClickException("fetchprob is currently disabled (BOJ closing)")


cli.add_command(register)
cli.add_command(create)
cli.add_command(run)
cli.add_command(load)
cli.add_command(init)
cli.add_command(export)
cli.add_command(state)
cli.add_command(show)
cli.add_command(find)
cli.add_command(fetchprob)

if __name__ == "__main__":
    cli()