import requests
import json
import warnings
import os
import sys
import libyang
import re
import time

from requests.auth import HTTPBasicAuth
from urllib3.exceptions import InsecureRequestWarning
from dataclasses import dataclass
from infamy.transport import Transport, infer_put_dict
from . import env

# We know we have a self-signed certificate, silence warning about it
warnings.simplefilter('ignore', InsecureRequestWarning)

@dataclass
class Location:
    interface: str
    host: str
    username: str
    password: str
    port: int = 443

def xpath_to_uri(xpath, extra=None):
    """Convert xpath to HTTP URI"""
    pattern = r'\[(.*?)=["\'](.*?)["\']\]'
    matches = re.findall(pattern, xpath)

    uri_path = xpath
    if matches:
        for key, value in matches:
            # replace [key=value] with =value
            uri_path = re.sub(rf'\[{re.escape(key)}=["\']{re.escape(value)}["\']\]', f'={value}', uri_path)

    # Append extra if provided
    if extra is not None:
        uri_path = f"{uri_path}/{extra}"

    return uri_path


# Workaround for bug in requests 2.32.x: https://github.com/psf/requests/issues/6735
def requests_workaround(method, url, json, headers, auth, verify=False, retry=0):
    # Create a session
    session = requests.Session()

    # Prepare the request
    request = requests.Request(method, url, json=json, headers=headers,
                               auth=auth)
    prepared_request = session.prepare_request(request)
    prepared_request.url = prepared_request.url.replace('%25', '%')
    prepared_request.url = prepared_request.url.replace('%3A', ':')
    response = session.send(prepared_request, verify=verify)
    try:
        # Raise exceptions for HTTP errors
        response.raise_for_status()
    except Exception as e:
        # most likely caused by nginx up, but not yet rousette
        if e.response.status_code == 502 and retry < 10:
            retry = retry + 1
            print(f"{method} {url}: HTTP error 502, retrying({retry})")
            time.sleep(1)
            response = requests_workaround(method, url, json, headers, auth,
                                           verify, retry)
        else:
            raise e

    return response


def requests_workaround_put(url, json, headers, auth, verify=False):
    return requests_workaround('PUT', url, json, headers, auth, verify=False)


def requests_workaround_delete(url, headers, auth, verify=False):
    return requests_workaround('DELETE', url, None, headers, auth, verify=False)


def requests_workaround_post(url, json, headers, auth, verify=False):
    return requests_workaround('POST', url, json, headers, auth, verify=False)


def requests_workaround_get(url, headers, auth, verify=False):
    return requests_workaround('GET', url, None, headers, auth, verify=False)


def restconf_reachable(neigh, password):
    try:
        headers = {
            'Content-Type': 'application/yang-data+json',
            'Accept': 'application/yang-data+json'
        }
        url = f"https://[{neigh}]/restconf/data/ietf-system:system/hostname"
        auth = HTTPBasicAuth("admin", password)

        response = requests_workaround_get(url, headers=headers, auth=auth,
                                           verify=False)
        if response.status_code == 200:
            return True
    except:
        return False

    return False


class Device(Transport):
    def __init__(self,
                 name: str,
                 location: Location,
                 mapping: dict,
                 yangdir: None | str = None):
        print("Testing using RESTCONF")

        self.name = name
        self.location = location
        self.mapping = mapping
        self.url_base = f"https://[{location.host}]:{location.port}"
        self.restconf_url = f"{self.url_base}/restconf"
        self.yang_url = f"{self.url_base}/yang"
        self.rpc_url = f"{self.url_base}/restconf/operations"
        self.headers = {
            'Content-Type': 'application/yang-data+json',
            'Accept': 'application/yang-data+json'
        }
        self.auth = HTTPBasicAuth(location.username, location.password)
        self.modules = {}

        self.lyctx = libyang.Context(yangdir)
        self._ly_bootstrap(yangdir)
        self._ly_init(yangdir)

    def __str__(self):
        nm = f"{self.name}"
        if env.ENV.ltop:
            nm += f"({env.ENV.ltop.xlate(self.name)})"
        return nm + " [RESTCONF]"

    def get_schemas_list(self):
        modules = self.get_operational("/ietf-yang-library:modules-state")
        data = modules.print_dict()
        return data["modules-state"]["module"]

    def get_schema(self, name, revision, yangdir):
        schema_name = f"{name}@{revision}.yang"
        url = f"{self.yang_url}/{schema_name}"
        data = self._get_raw(url=url, parse=False)

        data = data.decode('utf-8')
        with open(f"{yangdir}/{schema_name}", 'w') as json_file:
            json_file.write(data)

    def schema_exist(self, name, revision, yangdir):
        schema_name = f"{name}@{revision}.yang"
        schema_path = f"{yangdir}/{schema_name}"
        return os.path.exists(schema_path)

    def _ly_bootstrap(self, yangdir):
        schemas = self.get_schemas_list()
        for schema in schemas:
            if not self.schema_exist(schema["name"], schema["revision"], yangdir):
                self.get_schema(schema["name"], schema["revision"], yangdir)
            if schema.get("submodule"):
                for submodule in schema["submodule"]:
                    if not self.schema_exist(submodule["name"], submodule["revision"], yangdir):
                        self.get_schema(submodule["name"], submodule["revision"], yangdir)

            if not any("submodule" in x and schema["name"] in x["submodule"] for x in schemas):
                self.modules.update({schema["name"]: schema})

        print("YANG models downloaded.")

    def _ly_init(self, yangdir):
        for ms in self.modules.values():
            if ms["conformance-type"] != "implement":
                continue

            mod = self.lyctx.load_module(ms["name"])

            # TODO: ms["feature"] contains the list of enabled
            # features, so ideally we should only enable the supported"
            # ones. However, features can depend on each other, so the
            # naïve looping approach doesn't work.
            mod.feature_enable_all()

    def _get_raw(self, url, parse=True):
        """Actually send a GET to RESTCONF server"""
        response = requests_workaround_get(url, headers=self.headers,
                                           auth=self.auth, verify=False)
        # Raise exceptions for HTTP errors
        response.raise_for_status()
        if parse:
            data = response.json()
            data = self.lyctx.parse_data_mem(json.dumps(data), "json",
                                             parse_only=True)
            return data
        return response.content

    def get_datastore(self, datastore="operational", path="", parse=True):
        """Get a datastore"""
        dspath = f"/ds/ietf-datastores:{datastore}"
        if path is not None:
            dspath = f"{dspath}{path}"

        url = f"{self.restconf_url}{dspath}"
        try:
            return self._get_raw(url, parse)
        except requests.exceptions.HTTPError as e:
            if e.response.status_code == 404:
                return None
            else:
                raise e

    def get_running(self, path=None):
        """Wrapper function to get running datastore"""
        return self.get_datastore("running", path)

    def get_operational(self, path=None, parse=True):
        """Wrapper function to get operational datastore"""
        return self.get_datastore("operational", path, parse)

    def get_factory(self, path=None):
        """Wrapper function to get factory defaults"""
        return self.get_datastore("factory-default", path)

    def post_datastore(self, datastore, data):
        """Actually send a POST to RESTCONF server"""
        url = f"{self.restconf_url}/ds/ietf-datastores:{datastore}"
        # Directly pass the dictionary without using json.dumps
        response = requests_workaround_post(url,
                                            json=data,
                                            headers=self.headers,
                                            auth=self.auth,
                                            verify=False)
        # Raise exceptions for HTTP errors
        response.raise_for_status()

    def put_datastore(self, datastore, data):
        """Actually send a PUT to RESTCONF server"""

        # Directly pass the dictionary without using json.dumps
        response = requests_workaround_put(
            f"{self.restconf_url}/ds/ietf-datastores:{datastore}",
            json=data,
            headers=self.headers,
            auth=self.auth,
            verify=False
        )

        # Raise exceptions for HTTP errors
        response.raise_for_status()

    def get_config_dict(self, modname):
        """Get all configuration for module @modname as dictionary"""
        ds = self.get_running(modname)
        ds = json.loads(ds.print_mem("json", with_siblings=True, pretty=False))
        model, container = modname.split(":")
        for k, v in ds.items():
            return {container: v}

    def put_config_dicts(self, models):
        """PUT full configuration of all models to running-config"""
        infer_put_dict(self.name, models)
        running = self.get_running()

        for model in models.keys():
            mod = self.lyctx.get_module(model)
            lyd = mod.parse_data_dict(models[model], no_state=True, validate=False)
            running.merge(lyd)

        cfg = running.print_mem("json", with_siblings=True, pretty=True)
        # print(f"PUT new running-config: {cfg}")
        return self.put_datastore("running", json.loads(cfg))

    def put_config_dict(self, modname, edit):
        """Add @edit to running config and put the whole configuration"""

        # This is hacky, refactor when rousette have PATCH support.
        running = self.get_running()
        mod = self.lyctx.get_module(modname)

        for k, _ in edit.items():
            module = modname + ":" + k
            break

        # Ugly hack, but this function should be refactored when patch
        # is available in rousette anyway.
        rundict = json.loads(running.print_mem("json", with_siblings=True,
                                               pretty=False))
        if rundict.get(module) is None:
            rundict[module] = {}
            running = self.lyctx.parse_data_mem(json.dumps(rundict), "json",
                                                parse_only=True)

        change = mod.parse_data_dict(edit, no_state=True, validate=False)
        running.merge_module(change)
        cfg = running.print_mem("json", with_siblings=True, pretty=False)
        # print(f"PUT new running-config: {cfg}")
        data = json.loads(cfg)

        return self.put_datastore("running", data)

    def call_dict(self, model, call):
        pass # Need implementation

    def call_rpc(self, rpc):
        """Actually send a POST to RESTCONF server"""
        url = f"{self.rpc_url}/{rpc}"
        response = requests_workaround_post(
            url,
            json=None,
            headers=self.headers,
            auth=self.auth,
            verify=False
        )
        response.raise_for_status()  # Raise an exception for HTTP errors

    def get_dict(self, xpath=None, parse=True):
        """NETCONF compat function, just wraps get_data"""
        return self.get_data(xpath, parse)

    def get_data(self, xpath=None, parse=True):
        """Get operational data"""
        uri = xpath_to_uri(xpath) if xpath is not None else None
        data = self.get_operational(uri, parse)

        if parse and data:
            return data.print_dict()

        return data

    def copy(self, source, target):
        factory = self.get_datastore(source)
        data = factory.print_mem("json", with_siblings=True, pretty=False)
        self.put_datastore(target, json.loads(data))

    def reboot(self):
        self.call_rpc("ietf-system:system-restart")

    def call_action(self, xpath):
        path = xpath_to_uri(xpath)
        url = f"{self.restconf_url}/data{path}"
        response = requests_workaround_post(
            url,
            json=None,
            headers=self.headers,
            auth=self.auth,
            verify=False
        )

        # Raise exceptions for HTTP errors
        response.raise_for_status()

        return response.content

    def delete_xpath(self, xpath):
        """Delete XPath from running config"""
        path = f"/ds/ietf-datastores:running{xpath_to_uri(xpath)}"
        url = f"{self.restconf_url}{path}"
        response = requests_workaround_delete(url, headers=self.headers,
                                              auth=self.auth, verify=False)

        # Raise exceptions for HTTP errors
        response.raise_for_status()

        return True