import time
from urllib.parse import urljoin

import requests
from tenacity import retry, stop_after_attempt, wait_fixed, before_sleep_log

from consts.consts import ENV_DEV, ENV_STAGING, ENV_PROD
from errors.errors import BadRequestException
from svc.measuring import EDA_DATAAPI_HISTOGRAM
from utils.logging import logging

logger = logging.getLogger(__name__)

# Cloud provider constant for AliCloud
CLOUD_PROVIDER_ALICLOUD = "alicloud"


def get_global_inner_domain(env: str):
    if env == ENV_DEV:
        return "https://inner-central.dev.tidbcloud.com"
    elif env == ENV_STAGING:
        return "https://inner-central.staging.tidbcloud.com"
    elif env == ENV_PROD:
        return "https://inner-central.prod.tidbcloud.com"
    else:
        raise BadRequestException(f"invalid env: {env}")


def get_o11y_region_inner_domain(env: str, region: str):
    if env == ENV_DEV or env == ENV_STAGING:
        region = "us-west-2"

    return "https://" + region + ".inner-region.o11y." + env + ".tidbcloud.com"


def get_alicloud_region_inner_domain(env: str, region: str):
    """
    Get AliCloud regional inner domain.
    Format: https://regionalsvc01.{region}.{env}.alicloud.tidbcloud.com

    Examples:
    - https://regionalsvc01.ap-southeast-1.prod.alicloud.tidbcloud.com
    - https://regionalsvc01.us-west-2.dev.alicloud.tidbcloud.com
    """
    return f"https://regionalsvc01.{region}.{env}.alicloud.tidbcloud.com"


def get_o11y_region_inner_domain_with_provider(env: str, region: str, provider: str):
    """
    Get regional inner domain based on provider.
    For AliCloud, uses the new AliCloud domain format.
    For others (AWS), uses the existing o11y domain format.
    """
    provider = (provider or "").strip().lower()
    if provider == CLOUD_PROVIDER_ALICLOUD:
        return get_alicloud_region_inner_domain(env, region)
    return get_o11y_region_inner_domain(env, region)


def get_provider_scoped_dataservice_path(provider: str, url: str):
    """
    Get provider-scoped inner dataservice path.
    For AliCloud, adds /dataservice prefix to the path.
    For others, returns the original path.

    Examples:
    - AliCloud: /inner/dataservice/exec/sql -> /dataservice/inner/dataservice/exec/sql
    - AWS: /inner/dataservice/exec/sql -> /inner/dataservice/exec/sql
    """
    provider = (provider or "").strip().lower()
    if provider == CLOUD_PROVIDER_ALICLOUD:
        return "/dataservice" + url
    return url


class CrossRegionClient:
    def __init__(self, env: str, basic_auth_encoded: str, trace_id: str = "") -> None:
        self.env = env

        self.trace_id = trace_id
        self.basic_auth_encoded = basic_auth_encoded

    def request_global(self, method, url, **kwargs):
        s = requests.Session()
        base_url = get_global_inner_domain(self.env)
        full_url = urljoin(base_url, url)
        headers = kwargs.get("headers", {})
        headers["Authorization"] = f"Basic {self.basic_auth_encoded}"
        headers["B3"] = self.trace_id
        kwargs["headers"] = headers

        start = time.time()
        resp = s.request(method, full_url, **kwargs)
        logging.info("request global, url, method, args, resp code, body: %s, %s, %s, %s, %s", full_url, method, kwargs, resp.status_code, resp.text)

        EDA_DATAAPI_HISTOGRAM.labels(region="global", url=url, status=resp.status_code).observe(time.time() - start)
        return resp

    @retry(reraise=True, wait=wait_fixed(3), stop=stop_after_attempt(5), before_sleep=before_sleep_log(logger, logging.INFO))
    def request_o11y(self, region, method, url, **kwargs):
        s = requests.Session()
        base_url = get_o11y_region_inner_domain(self.env, region)
        full_url = urljoin(base_url, url)
        headers = kwargs.get("headers", {})
        headers["Authorization"] = f"Basic {self.basic_auth_encoded}"
        kwargs["headers"] = headers
        headers["B3"] = self.trace_id

        start = time.time()
        resp = s.request(method, full_url, **kwargs)
        logging.info("request o11y, url, region, method, args, resp code, body: %s, %s, %s, %s, %s, %s", full_url, region, method, kwargs, resp.status_code, resp.text)

        EDA_DATAAPI_HISTOGRAM.labels(region=region, url=url, status=resp.status_code).observe(time.time() - start)
        return resp

    @retry(reraise=True, wait=wait_fixed(3), stop=stop_after_attempt(5), before_sleep=before_sleep_log(logger, logging.INFO))
    def request_o11y_with_provider(self, region, provider, method, url, **kwargs):
        """
        Request to o11y regional endpoint with provider support.
        For AliCloud provider:
        - Uses AliCloud domain: https://regionalsvc01.{region}.{env}.alicloud.tidbcloud.com
        - Adds /dataservice prefix to the path

        Args:
            region: The region to send the request to
            provider: Cloud provider (e.g., 'alicloud', 'aws')
            method: HTTP method
            url: API path (e.g., '/inner/dataservice/exec/sql')
            **kwargs: Additional request arguments
        """
        s = requests.Session()
        base_url = get_o11y_region_inner_domain_with_provider(self.env, region, provider)
        scoped_url = get_provider_scoped_dataservice_path(provider, url)
        full_url = urljoin(base_url, scoped_url)
        headers = kwargs.get("headers", {})
        headers["Authorization"] = f"Basic {self.basic_auth_encoded}"
        kwargs["headers"] = headers
        headers["B3"] = self.trace_id

        start = time.time()
        resp = s.request(method, full_url, **kwargs)
        logging.info(
            "request o11y with provider, url, region, provider, method, args, resp code, body: %s, %s, %s, %s, %s, %s, %s",
            full_url, region, provider, method, kwargs, resp.status_code, resp.text
        )

        EDA_DATAAPI_HISTOGRAM.labels(region=region, url=url, status=resp.status_code).observe(time.time() - start)
        return resp