import base64
import requests
import config


def _headers() -> dict:
    return {
        "Authorization": f"token {config.GITEA_TOKEN}",
        "Content-Type": "application/json",
    }


def get_file(owner: str, repo: str, path: str, branch: str) -> tuple[str, str]:
    """Fetch a file's decoded content and its SHA from Gitea.

    Returns:
        (content, sha) where content is the decoded UTF-8 string and sha is
        required for the subsequent update call.
    """
    url = f"{config.GITEA_URL}/api/v1/repos/{owner}/{repo}/contents/{path}"
    response = requests.get(url, headers=_headers(), params={"ref": branch}, timeout=30)
    response.raise_for_status()
    data = response.json()
    content = base64.b64decode(data["content"]).decode("utf-8")
    return content, data["sha"]


def update_file(
    owner: str,
    repo: str,
    path: str,
    content: str,
    sha: str,
    branch: str,
    commit_message: str | None = None,
) -> None:
    """Write updated file content back to Gitea."""
    url = f"{config.GITEA_URL}/api/v1/repos/{owner}/{repo}/contents/{path}"
    payload = {
        "message": commit_message or f"BLIGHT: process triggers in {path}",
        "content": base64.b64encode(content.encode("utf-8")).decode("ascii"),
        "sha": sha,
        "branch": branch,
    }
    response = requests.put(url, headers=_headers(), json=payload, timeout=30)
    response.raise_for_status()