"""
Shared Gitea REST helpers (stdlib). Used by gitea_api.py CLI and mcp_server_gitea.py.
"""
from __future__ import annotations

import json
import os
import urllib.error
import urllib.request
from pathlib import Path
from typing import Any


def load_dotenv(repo_root: Path) -> None:
    env_path = repo_root / ".env"
    if not env_path.is_file():
        return
    for line in env_path.read_text(encoding="utf-8", errors="replace").splitlines():
        line = line.strip()
        if not line or line.startswith("#"):
            continue
        if "=" not in line:
            continue
        k, _, v = line.partition("=")
        k, v = k.strip(), v.strip().strip('"').strip("'")
        if k and k not in os.environ:
            os.environ[k] = v


def repo_root() -> Path:
    return Path(__file__).resolve().parents[2]


def get_config() -> tuple[str, str, str, str]:
    base = os.getenv("GITEA_BASE_URL", "").rstrip("/")
    token = os.getenv("GITEA_TOKEN", "")
    owner = os.getenv("GITEA_OWNER", "")
    reponame = os.getenv("GITEA_REPO", "")
    return base, token, owner, reponame


def require_config() -> tuple[str, str, str, str]:
    base, token, owner, reponame = get_config()
    missing = [n for n, v in (
        ("GITEA_BASE_URL", base),
        ("GITEA_TOKEN", token),
        ("GITEA_OWNER", owner),
        ("GITEA_REPO", reponame),
    ) if not v]
    if missing:
        raise RuntimeError(
            "Fehlende Umgebungsvariablen: " + ", ".join(missing)
            + " — setze sie in .env im Repo-Root oder in der MCP-env."
        )
    return base, token, owner, reponame


def request_json(
    method: str,
    url: str,
    token: str,
    data: dict | None = None,
) -> tuple[int, Any]:
    body = None if data is None else json.dumps(data).encode("utf-8")
    req = urllib.request.Request(url, data=body, method=method)
    req.add_header("Authorization", f"token {token}")
    req.add_header("Accept", "application/json")
    if body is not None:
        req.add_header("Content-Type", "application/json")
    try:
        with urllib.request.urlopen(req, timeout=120) as resp:
            raw = resp.read().decode("utf-8", errors="replace")
            status = resp.status
    except urllib.error.HTTPError as e:
        raw = e.read().decode("utf-8", errors="replace")
        try:
            return e.code, json.loads(raw) if raw else {}
        except json.JSONDecodeError:
            return e.code, {"message": raw or str(e)}
    if not raw:
        return status, {}
    try:
        return status, json.loads(raw)
    except json.JSONDecodeError:
        return status, raw


def issues_list_page(
    base: str,
    token: str,
    owner: str,
    repo: str,
    *,
    state: str = "open",
    page: int = 1,
    limit: int = 50,
) -> tuple[int, list]:
    if state == "all":
        open_st, open_i = issues_list_page(
            base, token, owner, repo, state="open", page=page, limit=limit
        )
        closed_st, closed_i = issues_list_page(
            base, token, owner, repo, state="closed", page=page, limit=limit
        )
        merged = (open_i or []) + (closed_i or [])
        st = max(open_st, closed_st) if open_st >= 400 or closed_st >= 400 else 200
        return st, merged[:limit]
    q = f"?state={state}&page={page}&limit={limit}"
    url = f"{base}/api/v1/repos/{owner}/{repo}/issues{q}"
    status, payload = request_json("GET", url, token)
    if status >= 400:
        return status, []
    if not isinstance(payload, list):
        return status, []
    return status, payload


def issues_list_all(
    base: str,
    token: str,
    owner: str,
    repo: str,
    *,
    state: str = "open",
    limit: int = 50,
) -> list[dict]:
    if state == "all":
        o = issues_list_all(
            base, token, owner, repo, state="open", limit=limit
        )
        c = issues_list_all(
            base, token, owner, repo, state="closed", limit=limit
        )
        return o + c
    out: list[dict] = []
    page = 1
    while True:
        _, batch = issues_list_page(
            base, token, owner, repo, state=state, page=page, limit=limit
        )
        if not batch:
            break
        out.extend(batch)
        if len(batch) < limit:
            break
        page += 1
    return out


def issues_get(
    base: str, token: str, owner: str, repo: str, number: int
) -> tuple[int, Any]:
    url = f"{base}/api/v1/repos/{owner}/{repo}/issues/{number}"
    return request_json("GET", url, token)


def issues_create(
    base: str,
    token: str,
    owner: str,
    repo: str,
    *,
    title: str,
    body: str = "",
    labels: list[str] | None = None,
) -> tuple[int, Any]:
    url = f"{base}/api/v1/repos/{owner}/{repo}/issues"
    return request_json(
        "POST",
        url,
        token,
        {"title": title, "body": body, "labels": labels or []},
    )


def issues_comment(
    base: str,
    token: str,
    owner: str,
    repo: str,
    number: int,
    body: str,
) -> tuple[int, Any]:
    url = f"{base}/api/v1/repos/{owner}/{repo}/issues/{number}/comments"
    return request_json("POST", url, token, {"body": body})


def issues_patch(
    base: str,
    token: str,
    owner: str,
    repo: str,
    number: int,
    fields: dict,
) -> tuple[int, Any]:
    """Gitea: PATCH issue (state, title, body, …)."""
    url = f"{base}/api/v1/repos/{owner}/{repo}/issues/{number}"
    return request_json("PATCH", url, token, fields)


def repo_file_content(
    base: str,
    token: str,
    owner: str,
    repo: str,
    path: str,
    ref: str = "",
) -> tuple[int, Any]:
    from urllib.parse import quote
    from base64 import b64decode

    p = quote(path, safe="/")
    r = f"?ref={ref}" if ref else ""
    url = f"{base}/api/v1/repos/{owner}/{repo}/contents/{p}{r}"
    st, payload = request_json("GET", url, token)
    if st >= 400:
        return st, payload
    if isinstance(payload, dict) and payload.get("type") == "file" and payload.get(
        "content"
    ):
        try:
            text = b64decode(payload["content"]).decode("utf-8", errors="replace")
            return st, {"path": path, "encoding": "text", "content": text}
        except Exception:
            return st, payload
    return st, payload