from __future__ import annotations

import time
from datetime import datetime, timezone
from typing import Any

from .db import read_sys_config_value, write_sys_config_value
from .http_client import request_json


PROJECTS_CONFIG_KEY = "mcp_data_collector_projects"
PROJECT_TOKEN_CONFIG_KEY_PREFIX = "mcp_data_collector_token_"
PROJECT_AUTH_LOGIN_PATH = "/api/ai/auth/password_login"


def _to_iso_utc(timestamp: float) -> str:
    return datetime.fromtimestamp(timestamp, tz=timezone.utc).isoformat().replace("+00:00", "Z")


def _normalize_project_key(raw_value: Any) -> str:
    project_key = str(raw_value or "").strip()
    if not project_key:
        raise ValueError("project_key is required")
    return project_key


def _normalize_base_url(raw_value: Any, field_name: str) -> str:
    base_url = str(raw_value or "").strip().rstrip("/")
    if not base_url:
        raise ValueError(f"{field_name} is required")
    return base_url


def _coerce_bool(raw_value: Any, default: bool) -> bool:
    if raw_value is None:
        return default
    if isinstance(raw_value, bool):
        return raw_value
    text = str(raw_value).strip().lower()
    if text in {"1", "true", "yes", "y", "on"}:
        return True
    if text in {"0", "false", "no", "n", "off"}:
        return False
    return default


def _safe_int(raw_value: Any, field_name: str) -> int:
    try:
        return int(str(raw_value).strip())
    except Exception as exc:
        raise ValueError(f"invalid {field_name}: {raw_value}") from exc


def _project_token_config_key(project_key: str) -> str:
    return f"{PROJECT_TOKEN_CONFIG_KEY_PREFIX}{project_key}"


def load_projects_config() -> list[dict[str, Any]]:
    raw_value = read_sys_config_value(PROJECTS_CONFIG_KEY)
    if raw_value is None:
        raise ValueError(f"missing sys_config key: {PROJECTS_CONFIG_KEY}")
    if not isinstance(raw_value, list):
        raise ValueError(f"sys_config {PROJECTS_CONFIG_KEY} must be a JSON array")

    latest_by_key: dict[str, dict[str, Any]] = {}
    for item in raw_value:
        if not isinstance(item, dict):
            continue

        project_key = _normalize_project_key(item.get("project_key"))
        project_name = str(item.get("project_name") or project_key).strip() or project_key
        base_url = _normalize_base_url(item.get("base_url"), "base_url")
        data_collector_base_url = _normalize_base_url(
            item.get("data_collector_base_url"),
            "data_collector_base_url",
        )
        username = str(item.get("username") or "").strip()
        password = str(item.get("password") or "").strip()
        enabled = _coerce_bool(item.get("enabled"), True)

        latest_by_key[project_key] = {
            "project_key": project_key,
            "project_name": project_name,
            "base_url": base_url,
            "data_collector_base_url": data_collector_base_url,
            "username": username,
            "password": password,
            "enabled": enabled,
        }

    projects = list(latest_by_key.values())
    if not projects:
        raise ValueError(f"{PROJECTS_CONFIG_KEY} has no valid project entries")
    return projects


def find_project_config(project_key: str) -> dict[str, Any]:
    expected = _normalize_project_key(project_key)
    for item in load_projects_config():
        if item["project_key"] != expected:
            continue
        if not item["enabled"]:
            raise ValueError(f"project '{expected}' is disabled")
        if not item["username"]:
            raise ValueError(f"project '{expected}' missing username")
        if not item["password"]:
            raise ValueError(f"project '{expected}' missing password")
        return item
    raise ValueError(f"project_key not found: {expected}")


def _read_project_token_cache(project_key: str) -> dict[str, Any] | None:
    raw_value = read_sys_config_value(_project_token_config_key(project_key))
    if not isinstance(raw_value, dict):
        return None
    return raw_value


def _write_project_token_cache(project_key: str, *, auth_token: str, expire_at: int) -> None:
    write_sys_config_value(
        _project_token_config_key(project_key),
        {
            "auth_token": auth_token,
            "expire_at": expire_at,
            "updated_at": _to_iso_utc(time.time()),
        },
    )


def _login_project(project_cfg: dict[str, Any]) -> tuple[str, int]:
    payload = request_json(
        "POST",
        f"{project_cfg['base_url']}{PROJECT_AUTH_LOGIN_PATH}",
        json_payload={
            "username": project_cfg["username"],
            "password": project_cfg["password"],
        },
    )
    if not isinstance(payload, dict):
        raise ValueError("login failed: invalid response payload")

    errcode = payload.get("errcode")
    if str(errcode) not in {"0", "0.0"}:
        message = str(payload.get("msg") or payload.get("message") or "").strip()
        raise ValueError(f"login failed: {message or payload}")

    auth_token = str(payload.get("token") or "").strip()
    if not auth_token:
        raise ValueError("login failed: missing token")

    expire_raw = payload.get("token_expire_time")
    if expire_raw is None:
        expire_at = int(time.time()) + 3600
    else:
        expire_at = _safe_int(expire_raw, "token_expire_time")
        if expire_at <= int(time.time()):
            expire_at = int(time.time()) + 3600

    return auth_token, expire_at


def resolve_project_token(project_cfg: dict[str, Any]) -> str:
    project_key = project_cfg["project_key"]
    cached = _read_project_token_cache(project_key)
    if isinstance(cached, dict):
        token = str(cached.get("auth_token") or "").strip()
        expire_raw = cached.get("expire_at")
        if token and expire_raw is not None:
            try:
                if int(time.time()) < int(str(expire_raw).strip()):
                    return token
            except (TypeError, ValueError):
                pass

    auth_token, expire_at = _login_project(project_cfg)
    _write_project_token_cache(project_key, auth_token=auth_token, expire_at=expire_at)
    return auth_token