"""Shared helpers for the Windows installer trio (Setup.exe / service host /
Uninstall.exe). Kept dependency-light (stdlib + httpx only) so each frozen
binary stays small and self-contained; the DPAPI credential write reuses the
agent's `gti_fiscal_agent.credential_store` module.

Policy enforced here (mirrors CLAUDE.md):
- `agent.env` NEVER holds AGENT_TOKEN or any secret — only non-secret config.
- `credentials.bin` is DPAPI LocalMachine-encrypted with a
  SYSTEM/Administrators-only ACL (fail closed if DPAPI/icacls is unavailable).
- FIREBIRD_WRITES=0 and FISCAL_MODE=DRY_RUN are always written; no UI or flag
  ever enables writes or AI write.
- The install code is sent once to the Hub and is never persisted locally.
"""
from __future__ import annotations

import os
import subprocess
import sys
import winreg
from pathlib import Path

import httpx

PROD_HUB_URL = "https://gtifiscal.gtigrupo.com.br"
SERVICE_NAME = "GTIFiscalAgent"
SERVICE_DISPLAY = "GTI Fiscal Agent"
SERVICE_FAILURE = "restart/60000/restart/60000/restart/60000"
UNINSTALL_KEY = r"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\GTI Fiscal Agent"


def install_dir() -> Path:
    override = os.environ.get("GTI_INSTALL_DIR")
    if override:
        return Path(override).resolve()
    return Path(os.environ.get("PROGRAMFILES", r"C:\Program Files")) / "GTI" / "FiscalAgent"


def hub_url() -> str:
    return (os.environ.get("GTI_HUB_URL") or PROD_HUB_URL).rstrip("/")


def machine_fingerprint(max_len: int = 128) -> str:
    try:
        with winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, r"SOFTWARE\Microsoft\Cryptography") as key:
            value, _ = winreg.QueryValueEx(key, "MachineGuid")
        return str(value)[:max_len]
    except OSError:
        return os.environ.get("COMPUTERNAME", "")[:max_len]


def enroll(install_code: str, *, hub: str | None = None) -> dict:
    """POST /v1/agents/enroll with the standalone install code. Returns the
    parsed JSON on success; raises httpx.HTTPStatusError with the Hub's reason
    in the response body otherwise."""
    url = (hub or hub_url()).rstrip("/") + "/v1/agents/enroll"
    payload = {
        "install_code": install_code,
        "hostname": os.environ.get("COMPUTERNAME", ""),
        "agent_version": os.environ.get("AGENT_VERSION", ""),
        "machine_fingerprint": machine_fingerprint(),
    }
    response = httpx.post(url, json=payload, timeout=30)
    response.raise_for_status()
    return response.json()


def write_agent_env(install_dir_path: Path, enroll_result: dict) -> None:
    """Write the non-secret agent.env. The permanent credential goes to
    credentials.bin (DPAPI), never here. FIREBIRD_WRITES=0 / DRY_RUN always."""
    from gti_fiscal_agent.runner import REFERENCE_SCHEMA_V1

    install = Path(install_dir_path)
    lines = [
        (f"GTI_HUB_URL={enroll_result.get('hub_url') or hub_url()}"),
        (f"AGENT_ID={enroll_result.get('agent_id') or ''}"),
        (f"INSTALLATION_ID={enroll_result.get('installation_id') or ''}"),
        ("COMPANY_ID="),
        ("COMPANY_UF="),
        ("FIREBIRD_DATABASE_PATH="),
        ("FB_USER="),
        ("FB_PASSWORD="),
        ("FISCAL_MODE=DRY_RUN"),
        ("FIREBIRD_WRITES=0"),
        (f"AGENT_VERSION={os.environ.get('AGENT_VERSION', '')}"),
        ("POLL_INTERVAL_SECONDS=15"),
        (f"AGENT_LOG_PATH={install / 'logs' / 'agent.log'}"),
        (f"AGENT_STATE_DB={install / 'agent_state.sqlite'}"),
        (f"EXPECTED_SCHEMA_FINGERPRINT={REFERENCE_SCHEMA_V1}"),
        (f"GTI_WRITE_EXECUTOR_PATH={install / 'scripts' / 'firebird_write_executor.py'}"),
        (f"AGENT_HOSTNAME={os.environ.get('COMPUTERNAME', '')}"),
        ("AUTHORIZED_WRITE_DATABASE_PATH="),
    ]
    install.mkdir(parents=True, exist_ok=True)
    (install / "agent.env").write_text("\n".join(lines) + "\n", encoding="utf-8")


def write_credential(install_dir_path: Path, agent_token: str) -> None:
    """Write credentials.bin via DPAPI LocalMachine + ACL (fail closed)."""
    from gti_fiscal_agent.credential_store import write_credential as _write

    install = Path(install_dir_path)
    install.mkdir(parents=True, exist_ok=True)
    _write(install / "credentials.bin", agent_token)


def _sc(args: list[str]) -> subprocess.CompletedProcess[str]:
    return subprocess.run(["sc.exe", *args], capture_output=True, text=True)


def install_service(install_dir_path: Path) -> None:
    """Register the service (Delayed Auto) and set its failure-recovery policy.
    The frozen onedir host lives in <install>/GTIFiscalAgentService/ ; SCM's
    binPath points at that executable (its `_internal/` dir travels with it)."""
    exe = Path(install_dir_path) / "GTIFiscalAgentService" / "GTIFiscalAgentService.exe"
    bin_path = f"\"{exe}\""
    result = _sc(["create", SERVICE_NAME, "binPath=", bin_path, "start=", "auto", "DisplayName=", SERVICE_DISPLAY])
    if result.returncode != 0 and "already exists" not in (result.stdout + result.stderr):
        raise RuntimeError(f"sc create failed: {result.stdout} {result.stderr}".strip())
    _sc(["config", SERVICE_NAME, "start=", "delayed-auto"])
    _sc(["config", SERVICE_NAME, "obj=", "LocalSystem"])
    failure = _sc(["failure", SERVICE_NAME, "reset=", "86400", "actions=", SERVICE_FAILURE])
    if failure.returncode != 0:
        raise RuntimeError(f"sc failure failed: {failure.stdout} {failure.stderr}".strip())
    config = _sc(["qc", SERVICE_NAME])
    if "DELAYED" not in (config.stdout + config.stderr).upper() and config.returncode == 0:
        raise RuntimeError("sc config: delayed-auto did not stick")


def service_installed() -> bool:
    result = _sc(["query", SERVICE_NAME])
    return result.returncode == 0 and ("SERVICE_NAME" in result.stdout or "RUNNING" in result.stdout or "STOPPED" in result.stdout)


def service_running() -> bool:
    result = _sc(["query", SERVICE_NAME])
    return "RUNNING" in result.stdout


def start_service() -> None:
    _sc(["start", SERVICE_NAME])


def stop_service() -> None:
    _sc(["stop", SERVICE_NAME])


def remove_service() -> None:
    """Stop then delete the service; both best effort (idempotent)."""
    stop_service()
    _sc(["delete", SERVICE_NAME])


def write_arp_uninstall(install_dir_path: Path) -> None:
    """Write the Add/Remove Programs entry pointing to Uninstall.exe."""
    install = Path(install_dir_path)
    with winreg.CreateKeyEx(winreg.HKEY_LOCAL_MACHINE, UNINSTALL_KEY, 0, winreg.KEY_WRITE) as key:
        winreg.SetValueEx(key, "DisplayName", 0, winreg.REG_SZ, SERVICE_DISPLAY)
        winreg.SetValueEx(key, "DisplayVersion", 0, winreg.REG_SZ, os.environ.get("AGENT_VERSION", ""))
        winreg.SetValueEx(key, "Publisher", 0, winreg.REG_SZ, "GTI Sistemas")
        winreg.SetValueEx(key, "InstallLocation", 0, winreg.REG_SZ, str(install))
        winreg.SetValueEx(key, "UninstallString", 0, winreg.REG_SZ, str(install / "Uninstall.exe"))
        winreg.SetValueEx(key, "DisplayIcon", 0, winreg.REG_SZ, str(install / "GTIFiscalAgentService" / "GTIFiscalAgentService.exe"))
        winreg.SetValueEx(key, "NoModify", 0, winreg.REG_DWORD, 1)
        winreg.SetValueEx(key, "NoRepair", 0, winreg.REG_DWORD, 1)


def remove_arp_entry() -> None:
    try:
        winreg.DeleteKey(winreg.HKEY_LOCAL_MACHINE, UNINSTALL_KEY)
    except OSError:
        pass


def audit_event(agent_token: str, hub: str, event_type: str, message: str) -> None:
    """Best-effort authenticated event POST (WINDOWS_INSTALL_COMPLETED etc.).
    Never sends secrets; ignores failures so a hub hiccup cannot fail an install."""
    try:
        response = httpx.post(
            (hub or hub_url()).rstrip("/") + "/v1/agents/events",
            json={"event_type": event_type, "message": message, "context": {"source": "setup.exe", "agent_version": os.environ.get("AGENT_VERSION", "")}},
            headers={"Authorization": f"Bearer {agent_token}"},
            timeout=15,
        )
        response.raise_for_status()
    except Exception:  # noqa: BLE001 — best effort only
        return