from __future__ import annotations

import os
import pwd
import subprocess
from pathlib import Path

from .config import Settings


class AiderAgent:
    def __init__(self, settings: Settings) -> None:
        self.settings = settings

    def run(self, workspace: Path, task: str) -> str:
        task_file = workspace / ".git" / "failure-task.txt"
        task_file.write_text(task)
        task_file.chmod(0o600)
        command = [
            self.settings.agent_command,
            "--model",
            self.settings.agent_model,
            "--message-file",
            str(task_file),
            "--yes",
            "--no-auto-commits",
            "--no-dirty-commits",
            "--no-stream",
        ]
        coder = pwd.getpwnam("coder")
        os.chown(task_file, coder.pw_uid, coder.pw_gid)
        for path in workspace.rglob("*"):
            if ".git" not in path.parts:
                os.chown(path, coder.pw_uid, coder.pw_gid, follow_symlinks=False)
        os.chown(workspace, coder.pw_uid, coder.pw_gid, follow_symlinks=False)

        environment = {
            "HOME": coder.pw_dir,
            "PATH": os.environ.get("PATH", "/usr/local/bin:/usr/bin:/bin"),
        }
        for name in ("MISTRAL_API_KEY", "OPENAI_API_KEY", "ANTHROPIC_API_KEY"):
            if os.getenv(name):
                environment[name] = os.environ[name]

        def drop_privileges() -> None:
            os.setgroups([])
            os.setgid(coder.pw_gid)
            os.setuid(coder.pw_uid)

        result = subprocess.run(
            command,
            cwd=workspace,
            env=environment,
            text=True,
            capture_output=True,
            check=False,
            preexec_fn=drop_privileges,
            timeout=3600,
        )
        if result.returncode != 0:
            raise RuntimeError(f"Aider failed ({result.returncode}): {result.stderr[-4000:]}")
        return result.stdout[-12_000:]