"""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 json
import os
import subprocess
import sys
import time
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, firebird_path: str = "") -> 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="),
        (f"FIREBIRD_DATABASE_PATH={firebird_path}"),
        # Firebird user/password live ONLY in the DPAPI-protected firebird.bin (never here, never sent to the Hub).
        ("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 write_firebird_credential(install_dir_path: Path, user: str, password: str) -> None:
    """Firebird user/password -> firebird.bin via DPAPI LocalMachine + ACL (fail closed).
    Local only: this never reaches the Hub and never lands in agent.env."""
    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 / "firebird.bin", json.dumps({"user": user, "password": password}))


def detect_existing(install_dir_path: Path) -> dict | None:
    """An already-enrolled installation (identity + DPAPI credential present)."""
    install = Path(install_dir_path)
    env_file, cred = install / "agent.env", install / "credentials.bin"
    if not env_file.exists() or not cred.exists():
        return None
    values = {}
    for line in env_file.read_text(encoding="utf-8", errors="replace").splitlines():
        if "=" in line and not line.lstrip().startswith("#"):
            key, _, value = line.partition("=")
            values[key.strip()] = value.strip()
    if not values.get("AGENT_ID"):
        return None
    return {"agent_id": values["AGENT_ID"], "installation_id": values.get("INSTALLATION_ID"), "hub_url": values.get("GTI_HUB_URL") or hub_url(), "env": values}


def upgrade_agent_env(install_dir_path: Path, agent_version: str) -> None:
    """Migrate an existing agent.env to the central-control model: drop the legacy local
    AGENT_JOBS_ENABLED toggle, refresh AGENT_VERSION, keep every other value (identity, Firebird path...)."""
    env_file = Path(install_dir_path) / "agent.env"
    kept, seen_version = [], False
    for line in env_file.read_text(encoding="utf-8", errors="replace").splitlines():
        key = line.partition("=")[0].strip()
        if key == "AGENT_JOBS_ENABLED":
            continue
        if key == "AGENT_VERSION":
            line, seen_version = f"AGENT_VERSION={agent_version}", True
        kept.append(line)
    if not seen_version:
        kept.append(f"AGENT_VERSION={agent_version}")
    env_file.write_text(chr(10).join(kept) + chr(10), encoding="utf-8")


def wait_service_state(wanted: str, timeout: float = 45.0) -> bool:
    deadline = time.time() + timeout
    while time.time() < deadline:
        if wanted in _sc(["query", SERVICE_NAME]).stdout:
            return True
        time.sleep(1.5)
    return False


def wait_for_heartbeat(agent_token: str, hub: str, timeout: float = 120.0) -> bool:
    """True once the Hub sees this Agent ONLINE (first heartbeat after the service started)."""
    deadline = time.time() + timeout
    while time.time() < deadline:
        try:
            response = httpx.get((hub or hub_url()).rstrip("/") + "/v1/agents/me", headers={"Authorization": f"Bearer {agent_token}"}, timeout=10)
            if response.status_code == 200 and response.json().get("status") == "ONLINE":
                return True
        except Exception:  # noqa: BLE001
            pass
        time.sleep(4)
    return False


def log_path() -> Path:
    return Path(os.environ.get("GTI_LOG_DIR") or os.path.join(os.environ.get("PROGRAMDATA", r"C:\ProgramData"), "GTI", "FiscalAgent")) / "installer.log"


def ilog(message: str) -> None:
    """Append one timestamped line to installer.log (best effort, never raises, never holds a secret)."""
    try:
        path = log_path()
        path.parent.mkdir(parents=True, exist_ok=True)
        with path.open("a", encoding="utf-8") as fh:
            fh.write(time.strftime("%Y-%m-%d %H:%M:%S ") + " ".join(message.split()) + chr(10))
    except Exception:  # noqa: BLE001
        pass


def _sc(args: list[str]) -> subprocess.CompletedProcess[str]:
    result = subprocess.run(["sc.exe", *args], capture_output=True, text=True)
    text = " ".join((result.stdout + " " + result.stderr).split())
    ilog(f"sc {' '.join(a for a in args if not a.lower().startswith('binpath'))} -> rc={result.returncode} {text[:300]}")
    return result


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])
    # 1073 = ERROR_SERVICE_EXISTS. Match the code, never the message: the text is localized (pt-BR: "já existe").
    if result.returncode not in (0, 1073) 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 service_state() -> str:
    out = subprocess.run(["sc.exe", "query", SERVICE_NAME], capture_output=True, text=True).stdout
    for name in ("RUNNING", "START_PENDING", "STOP_PENDING", "STOPPED", "PAUSED"):
        if name in out:
            return name
    return "UNKNOWN"


def service_process_alive() -> bool:
    out = subprocess.run(["sc.exe", "queryex", SERVICE_NAME], capture_output=True, text=True).stdout
    for line in out.splitlines():
        if line.strip().upper().startswith("PID"):
            pid = line.split(":", 1)[1].strip()
            if pid.isdigit() and int(pid) > 0:
                tl = subprocess.run(["tasklist", "/FI", f"PID eq {pid}", "/NH"], capture_output=True, text=True).stdout
                return pid in tl
    return False


def start_and_verify(attempts: int = 4, per_attempt: float = 60.0) -> tuple[bool, str]:
    """Start the service and prove it: RUNNING for a few seconds AND a live host process.
    The first start after fresh files often exceeds the SCM's 30 s limit (error 1053: antivirus scans the
    new onedir), so a failed attempt is diagnosed into installer.log and retried; the second start is fast."""
    detail = "not started"
    for attempt in range(1, attempts + 1):
        ilog(f"start attempt {attempt}/{attempts}; state={service_state()}")
        if service_state() != "RUNNING":
            _sc(["start", SERVICE_NAME])
        deadline = time.time() + per_attempt
        while time.time() < deadline and service_state() in ("START_PENDING", "STOP_PENDING", "UNKNOWN"):
            time.sleep(1.5)
        if service_state() == "RUNNING":
            time.sleep(6)  # must survive its own startup (preflight) rather than crash right after RUNNING
            if service_state() == "RUNNING" and service_process_alive():
                ilog("service RUNNING and host process alive")
                return True, "RUNNING"
        state = service_state()
        query = subprocess.run(["sc.exe", "query", SERVICE_NAME], capture_output=True, text=True).stdout
        exit_codes = " ".join(line.strip() for line in query.splitlines() if "EXIT_CODE" in line.upper())
        detail = f"attempt {attempt}: state={state} {exit_codes}".strip()
        ilog(detail)
        try:
            tail = (install_dir() / "logs" / "agent.log").read_text(encoding="utf-8", errors="replace").splitlines()[-3:]
            ilog("agent.log tail: " + " | ".join(tail)[:400])
        except Exception:  # noqa: BLE001
            pass
        time.sleep(5)
    ilog(f"service did NOT start: {detail}")
    return False, detail


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


def ensure_service_stopped(timeout: float = 45.0) -> None:
    """Stop the service and make sure its host process is really gone (an upgrade must be able
    to overwrite the executable): SCM stop, wait, then kill any leftover host process."""
    stop_service()
    if not wait_service_state("STOPPED", timeout=timeout):
        subprocess.run(["taskkill", "/F", "/IM", "GTIFiscalAgentService.exe"], capture_output=True, text=True)
        wait_service_state("STOPPED", timeout=15)
    time.sleep(2)


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