import argparse
import inspect
import json
import os
import sys
from pathlib import Path
from urllib.parse import urlsplit

from dotenv import load_dotenv
from ddgs import DDGS
import requests


def _load_env() -> None:
    cwd_env = Path.cwd() / ".env"
    if cwd_env.exists():
        load_dotenv(dotenv_path=cwd_env)
    else:
        repo_env = Path(__file__).resolve().parents[0] / ".env"
        if repo_env.exists():
            load_dotenv(dotenv_path=repo_env)

    if os.getenv("DDGS_PROXY", "") == "":
        os.environ.pop("DDGS_PROXY", None)


def _env_int(name: str, fallback: int | None) -> int | None:
    value = os.getenv(name)
    if value is None or value == "":
        return fallback
    try:
        return int(value)
    except ValueError:
        return fallback


def _env_str(name: str, fallback: str | None) -> str | None:
    value = os.getenv(name)
    if value is None or value == "":
        return fallback
    return value


def _build_parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(
        prog="ddgs-search",
        description="CLI scaffold for DuckDuckGo Search (DDGS) text search",
    )
    parser.add_argument(
        "query",
        nargs="+",
        help="Search query text",
    )
    parser.add_argument(
        "--region",
        default=_env_str("DDGS_REGION", "us-en"),
        help="Region code (default: DDGS_REGION or us-en)",
    )
    parser.add_argument(
        "--safesearch",
        choices=["on", "moderate", "off"],
        default=_env_str("DDGS_SAFESEARCH", "moderate"),
        help="Safe search level (default: DDGS_SAFESEARCH or moderate)",
    )
    parser.add_argument(
        "--timelimit",
        choices=["d", "w", "m", "y"],
        default=_env_str("DDGS_TIMELIMIT", None),
        help="Time limit: d/w/m/y (default: DDGS_TIMELIMIT)",
    )
    parser.add_argument(
        "--max-results",
        type=int,
        default=_env_int("DDGS_MAX_RESULTS", 10),
        help="Maximum number of results (default: DDGS_MAX_RESULTS or 10)",
    )
    parser.add_argument(
        "--backend",
        default=_env_str("DDGS_BACKEND", "auto"),
        help="Backend to use (default: DDGS_BACKEND or auto)",
    )
    parser.add_argument(
        "--proxy",
        default=_env_str("DDGS_PROXY", None),
        help="Proxy URL (default: DDGS_PROXY)",
    )
    parser.add_argument(
        "--timeout",
        type=int,
        default=_env_int("DDGS_TIMEOUT", 30),
        help="Request timeout seconds (default: DDGS_TIMEOUT or 30)",
    )
    verify_default = _env_str("DDGS_VERIFY", "true").lower() != "false"
    parser.add_argument(
        "--verify",
        dest="verify",
        action="store_true",
        default=verify_default,
        help="Enable SSL verification (default: DDGS_VERIFY or true)",
    )
    parser.add_argument(
        "--no-verify",
        dest="verify",
        action="store_false",
        help="Disable SSL verification (not recommended)",
    )
    parser.add_argument(
        "--format",
        choices=["json", "jsonl", "text"],
        default=_env_str("DDGS_OUTPUT", "json"),
        help="Output format: json, jsonl, text (default: DDGS_OUTPUT or json)",
    )
    return parser


def _print_text(results: list[dict]) -> None:
    for idx, item in enumerate(results, start=1):
        sys.stdout.write(f"[{idx}]\n")
        for key in sorted(item.keys()):
            value = item.get(key, "")
            sys.stdout.write(f"{key}: {value}\n")
        sys.stdout.write("\n")


def _print_json(results: list[dict], jsonl: bool) -> None:
    if jsonl:
        for item in results:
            sys.stdout.write(json.dumps(item, ensure_ascii=True) + "\n")
        return
    sys.stdout.write(json.dumps(results, ensure_ascii=True, indent=2) + "\n")


def _resolve_verify(verify_flag: bool) -> bool | str:
    if not verify_flag:
        return False
    ca_bundle = os.getenv("SSL_CERT_FILE") or os.getenv("REQUESTS_CA_BUNDLE")
    return ca_bundle or True


def _is_pdf_url(url: str) -> bool:
    try:
        path = urlsplit(url).path.lower()
    except ValueError:
        path = url.lower()
    return path.endswith(".pdf")


def _get_markdown_converter():
    try:
        from markitdown import MarkItDown
    except ImportError:
        return None
    session = requests.Session()
    session.headers.update(
        {
            "User-Agent": (
                "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) "
                "AppleWebKit/537.36 (KHTML, like Gecko) "
                "Chrome/122.0.0.0 Safari/537.36"
            ),
            "Accept": (
                "text/html,application/xhtml+xml,application/xml;q=0.9,"
                "application/json;q=0.8,*/*;q=0.7"
            ),
            "Accept-Language": "en-US,en;q=0.9",
            "DNT": "1",
            "Upgrade-Insecure-Requests": "1",
        }
    )
    return MarkItDown(requests_session=session)


def _convert_url_to_markdown(converter, url: str) -> str:
    if hasattr(converter, "convert_uri"):
        result = converter.convert_uri(url)
    elif hasattr(converter, "convert_url"):
        result = converter.convert_url(url)
    else:
        result = converter.convert(url)

    text = getattr(result, "markdown", None)
    if text is None:
        text = getattr(result, "text_content", None)
    if text is None:
        raise ValueError("MarkItDown result missing markdown content")
    return text


def _attach_markdown(results: list[dict]) -> None:
    converter = _get_markdown_converter()
    for item in results:
        url = item.get("href") or item.get("url")
        if not url or _is_pdf_url(url):
            item["markdown"] = None
            continue
        if converter is None:
            item["markdown"] = None
            item["markdown_error"] = "markitdown_not_installed"
            continue
        try:
            item["markdown"] = _convert_url_to_markdown(converter, url)
        except Exception as exc:  # noqa: BLE001 - surface conversion errors in response
            item["markdown"] = None
            item["markdown_error"] = str(exc)


def ddgs_search(
    query: str,
    *,
    region: str,
    safesearch: str,
    timelimit: str | None,
    max_results: int,
    backend: str | None,
    proxy: str | None,
    timeout: int,
    verify: bool,
) -> list[dict]:
    ddgs_kwargs: dict[str, object] = {
        "region": region,
        "safesearch": safesearch,
        "max_results": max_results,
    }
    if timelimit:
        ddgs_kwargs["timelimit"] = timelimit
    if backend:
        ddgs_kwargs["backend"] = backend

    ddgs_init_kwargs: dict[str, object] = {"timeout": timeout, "verify": _resolve_verify(verify)}
    if proxy:
        ddgs_params = inspect.signature(DDGS).parameters
        if "proxies" in ddgs_params:
            ddgs_init_kwargs["proxies"] = proxy
        elif "proxy" in ddgs_params:
            ddgs_init_kwargs["proxy"] = proxy

    with DDGS(**ddgs_init_kwargs) as ddgs:
        results = list(ddgs.text(query, **ddgs_kwargs))

    _attach_markdown(results)
    return results


def main(argv: list[str] | None = None) -> int:
    _load_env()
    parser = _build_parser()
    args = parser.parse_args(argv)

    query = " ".join(args.query)

    try:
        results = ddgs_search(
            query,
            region=args.region,
            safesearch=args.safesearch,
            timelimit=args.timelimit,
            max_results=args.max_results,
            backend=args.backend,
            proxy=args.proxy,
            timeout=args.timeout,
            verify=args.verify,
        )
    except Exception as exc:  # noqa: BLE001 - CLI should show all errors
        sys.stderr.write(f"Error: {exc}\n")
        return 1

    if args.format == "text":
        _print_text(results)
    elif args.format == "jsonl":
        _print_json(results, jsonl=True)
    else:
        _print_json(results, jsonl=False)

    return 0


if __name__ == "__main__":
    raise SystemExit(main())