import asyncio
import json
import os
import re
import time
from http import HTTPStatus
from pathlib import Path

import psutil
import pytest
import requests
from conftest import cleanup_eos_eosdash
from loguru import logger
from pydantic import ValidationError

from akkudoktoreos.config.configabc import is_home_assistant_addon
from akkudoktoreos.core.version import __version__
from akkudoktoreos.server.server import (
    ServerCommonSettings,
    get_default_host,
    get_default_port,
    get_host_ip,
    wait_for_port_free,
)


class TestServer:
    def test_server_setup_for_class(self, server_setup_for_class):
        """Ensure server is started."""
        server = server_setup_for_class["server"]
        eos_dir = server_setup_for_class["eos_dir"]

        # Assure server is running
        result = requests.get(f"{server}/v1/health", timeout=2)
        assert result.status_code == HTTPStatus.OK
        health = result.json()
        assert health["status"] == "alive"
        assert health["version"] == __version__

        result = requests.get(f"{server}/v1/config", timeout=2)
        assert result.status_code == HTTPStatus.OK

        # Get testing config
        config_json = result.json()
        config_folder_path = Path(config_json["general"]["config_folder_path"])
        config_file_path = Path(config_json["general"]["config_file_path"])
        data_folder_path = Path(config_json["general"]["data_folder_path"])
        data_ouput_path = Path(config_json["general"]["data_output_path"])
        # Assure we are working in test environment
        assert str(config_folder_path).startswith(eos_dir)
        assert str(config_file_path).startswith(eos_dir)
        assert str(data_folder_path).startswith(eos_dir)
        assert str(data_ouput_path).startswith(eos_dir)


class TestServerSettingsValidation:
    """Test the port restrictions in ServerCommonSettings when running as HA addon."""

    def test_ha_addon_default_ports_ok(self, config_eos, monkeypatch):
        """Default ports are accepted in HA addon mode."""
        monkeypatch.setattr("akkudoktoreos.server.server.is_home_assistant_addon", lambda: True)
        assert config_eos.server.port == get_default_port()  # 8503
        assert config_eos.server.eosdash_port == get_default_port() + 1  # 8504

    def test_server_port_restriction_in_ha_addon(self, config_eos, monkeypatch):
        """Server port must be the default (8503) in HA addon mode."""
        monkeypatch.setattr("akkudoktoreos.server.server.is_home_assistant_addon", lambda: True)
        with pytest.raises(ValidationError) as excinfo:
            config_eos.server.port = 9000
        assert "Server port number `8503` for Home Assistant add-on can not be changed" in str(
            excinfo.value
        )

    def test_eosdash_port_restriction_in_ha_addon(self, config_eos, monkeypatch):
        """EOSdash port must be the default (8504) in HA addon mode."""
        monkeypatch.setattr("akkudoktoreos.server.server.is_home_assistant_addon", lambda: True)
        with pytest.raises(ValidationError) as excinfo:
            config_eos.server.eosdash_port = 9001
        assert "EOSdash port number `8504` for Home Assistant add-on can not be changed" in str(
            excinfo.value
        )

    def test_ports_allowed_when_not_ha_addon(self, config_eos):
        """Custom ports are allowed when not in HA addon mode."""
        # is_home_assistant_addon() returns False by default in this test environment
        config_eos.server.port = 9000
        config_eos.server.eosdash_port = 9001
        assert config_eos.server.port == 9000
        assert config_eos.server.eosdash_port == 9001


class TestServerStartStop:
    @pytest.mark.asyncio
    async def test_forward_stream_truncates_very_long_line(self, monkeypatch, tmp_path):
        """Test logging from EOSdash can also handle very long lines."""

        eos_dir = tmp_path
        monkeypatch.setenv("EOS_DIR", str(eos_dir))
        monkeypatch.setenv("EOS_CONFIG_DIR", str(eos_dir))

        # Import after env vars are set
        from akkudoktoreos.server.rest.starteosdash import (
            EOSDASH_LOG_MAX_LINE_BYTES,
            _eosdash_log_worker,
            eosdash_log_queue,
            forward_stream,
        )

        # ---- Ensure queue + worker are initialized ----
        if eosdash_log_queue is None:
            from akkudoktoreos.server.rest import starteosdash

            starteosdash.eosdash_log_queue = asyncio.Queue(maxsize=10)
            worker_task = asyncio.create_task(_eosdash_log_worker())
        else:
            worker_task = None

        long_message = "X" * (EOSDASH_LOG_MAX_LINE_BYTES + 10_000)
        raw_line = f"INFO some.module:123 some_func - {long_message}\n"
        raw_bytes = raw_line.encode()

        reader = asyncio.StreamReader()
        reader.feed_data(raw_bytes)
        reader.feed_eof()

        # ---- Capture Loguru output ----
        records = []

        def sink(message):
            records.append(message.record)

        logger_id = logger.add(sink, level="INFO")

        try:
            await forward_stream(reader)

            # Allow log worker to flush queue
            await asyncio.sleep(0)

        finally:
            logger.remove(logger_id)

            # Clean shutdown of worker (important for pytest)
            if worker_task:
                from akkudoktoreos.server.rest import starteosdash

                if starteosdash.eosdash_log_queue:
                    starteosdash.eosdash_log_queue.put_nowait(None)
                await worker_task

        # ---- Assert ----
        assert len(records) == 1, "Expected exactly one log record"

        record = records[0]
        msg = record["message"]

        assert msg.endswith("[TRUNCATED]"), "Expected truncation marker"
        assert len(msg) <= EOSDASH_LOG_MAX_LINE_BYTES + 20

    @pytest.mark.asyncio
    async def test_server_start_eosdash(self, config_eos, monkeypatch, tmp_path):
        """Test the EOSdash server startup from EOS.

        Do not use any fixture as this will make pytest the owner of the EOSdash port.

        Tests that:
        1. EOSdash starts via the supervisor
        2. The /eosdash/health endpoint returns OK
        3. EOSdash reports correct status and version
        4. EOSdash can be terminated cleanly
        """
        eos_dir = tmp_path
        monkeypatch.setenv("EOS_DIR", str(eos_dir))
        monkeypatch.setenv("EOS_CONFIG_DIR", str(eos_dir))

        # Import with environment vars set to prevent creation of EOS.config.json in wrong dir.
        from akkudoktoreos.server.rest import starteosdash

        config_eos.server.host = get_default_host()
        config_eos.server.port = 8503
        config_eos.server.eosdash_host = config_eos.server.host
        config_eos.server.eosdash_port = 8504
        timeout = 120

        eosdash_server = f"http://{config_eos.server.eosdash_host}:{config_eos.server.eosdash_port}"

        # Port may be blocked
        assert wait_for_port_free(
            config_eos.server.eosdash_port, timeout=120, waiting_app_name="EOSdash"
        )

        owned_processes: list[psutil.Process] = []
        try:
            await starteosdash.supervise_eosdash()
            process = starteosdash.eosdash_proc
            assert process is not None, "EOSdash supervisor did not start a process"
            owned_processes.append(psutil.Process(process.pid))

            startup = False
            error = ""
            for _ in range(int(timeout / 3)):
                try:
                    resp = requests.get(f"{eosdash_server}/eosdash/health", timeout=2)
                    if resp.status_code == HTTPStatus.OK:
                        startup = True
                        break
                    error = f"{resp.status_code}, {str(resp.content)}"
                except requests.RequestException as ex:
                    error = str(ex)
                await asyncio.sleep(3)

            assert startup, f"Connection to {eosdash_server}/eosdash/health failed: {error}"
            health = resp.json()
            assert health.get("status") == "alive"
            assert health.get("version") == __version__
            assert health.get("pid") == process.pid

            # Terminate the process started by this test, then reap it via asyncio.
            process.terminate()
            await asyncio.wait_for(process.wait(), timeout=timeout)
            try:
                resp = requests.get(f"{eosdash_server}/eosdash/health", timeout=2)
            except requests.RequestException:
                pass
            else:
                assert resp.status_code != HTTPStatus.OK
        finally:
            cleanup_eos_eosdash(
                host=config_eos.server.host,
                port=config_eos.server.port,
                eosdash_host=config_eos.server.eosdash_host,
                eosdash_port=config_eos.server.eosdash_port,
                server_timeout=timeout,
                owned_processes=owned_processes,
                config_dir=str(config_eos.general.config_folder_path),
            )
            if starteosdash.eosdash_proc is not None:
                await asyncio.wait_for(starteosdash.eosdash_proc.wait(), timeout=timeout)

    @pytest.mark.skipif(os.name == "nt", reason="Server restart not supported on Windows")
    def test_server_restart(self, server_setup_for_function, is_system_test):
        """Test server restart."""
        server = server_setup_for_function["server"]
        eos_dir = server_setup_for_function["eos_dir"]
        timeout = server_setup_for_function["timeout"]

        result = requests.get(f"{server}/v1/config")
        assert result.status_code == HTTPStatus.OK

        # Get testing config
        config_json = result.json()
        config_folder_path = Path(config_json["general"]["config_folder_path"])
        config_file_path = Path(config_json["general"]["config_file_path"])
        data_folder_path = Path(config_json["general"]["data_folder_path"])
        data_ouput_path = Path(config_json["general"]["data_output_path"])
        cache_file_path = data_folder_path.joinpath(config_json["cache"]["subpath"]).joinpath(
            "cachefilestore.json"
        )
        # Assure we are working in test environment
        assert str(config_folder_path).startswith(eos_dir)
        assert str(config_file_path).startswith(eos_dir)
        assert str(data_folder_path).startswith(eos_dir)
        assert str(data_ouput_path).startswith(eos_dir)

        if is_system_test:
            # Prepare cache entry and get cached data
            result = requests.put(f"{server}/v1/config/weather/provider", json="BrightSky")
            assert result.status_code == HTTPStatus.OK

            result = requests.post(f"{server}/v1/prediction/update/BrightSky")
            assert result.status_code == HTTPStatus.OK

            result = requests.get(f"{server}/v1/prediction/series?key=weather_temp_air")
            assert result.status_code == HTTPStatus.OK
            data = result.json()
            assert data["data"] != {}

            result = requests.put(f"{server}/v1/config/file")
            assert result.status_code == HTTPStatus.OK

        # Save cache
        result = requests.post(f"{server}/v1/admin/cache/save")
        assert result.status_code == HTTPStatus.OK
        cache = result.json()

        assert cache_file_path.exists()

        result = requests.get(f"{server}/v1/admin/cache")
        assert result.status_code == HTTPStatus.OK
        cache = result.json()

        result = requests.get(f"{server}/v1/health")
        assert result.status_code == HTTPStatus.OK
        pid = result.json()["pid"]

        result = requests.post(f"{server}/v1/admin/server/restart")
        assert result.status_code == HTTPStatus.OK
        assert "Restarting EOS.." in result.json()["message"]
        new_pid = result.json()["pid"]

        # Wait for server to shut down
        for retries in range(10):
            try:
                result = requests.get(f"{server}/v1/health", timeout=2)
                if result.status_code == HTTPStatus.OK:
                    pid = result.json()["pid"]
                    if pid == new_pid:
                        # Already started
                        break
                else:
                    break
            except Exception as ex:
                break
            time.sleep(3)

        # Assure EOS is up again
        startup = False
        error = ""
        for retries in range(int(timeout / 5)):
            try:
                result = requests.get(f"{server}/v1/health", timeout=2)
                if result.status_code == HTTPStatus.OK:
                    startup = True
                    break
                error = f"{result.status_code}, {str(result.content)}"
            except Exception as ex:
                error = str(ex)
            time.sleep(5)

        assert startup, f"Connection to {server}/v1/health failed: {error}"
        assert result.json()["status"] == "alive"
        pid = result.json()["pid"]
        assert pid == new_pid

        result = requests.get(f"{server}/v1/admin/cache")
        assert result.status_code == HTTPStatus.OK
        new_cache = result.json()

        assert cache.items() <= new_cache.items()

        if is_system_test:
            result = requests.get(f"{server}/v1/config")
            assert result.status_code == HTTPStatus.OK
            assert result.json()["weather"]["provider"] == "BrightSky"

            # Wait for initialisation task to have finished
            time.sleep(5)

            result = requests.get(f"{server}/v1/prediction/series?key=weather_temp_air")
            assert result.status_code == HTTPStatus.OK
            assert result.json() == data

        # Shutdown the newly created server
        result = requests.post(f"{server}/v1/admin/server/shutdown")
        assert result.status_code == HTTPStatus.OK
        assert "Stopping EOS.." in result.json()["message"]
        new_pid = result.json()["pid"]


class TestServerWithEnv:
    eos_env = {
        "EOS_SERVER__EOSDASH_PORT": "8555",
    }

    def test_server_setup_for_class(self, server_setup_for_class):
        """Ensure server is started with environment passed to configuration."""
        server = server_setup_for_class["server"]

        assert server_setup_for_class["eosdash_port"] == int(
            self.eos_env["EOS_SERVER__EOSDASH_PORT"]
        )

        result = requests.get(f"{server}/v1/config")
        assert result.status_code == HTTPStatus.OK

        # Get testing config
        config_json = result.json()

        # Assure config got configuration from environment
        assert config_json["server"]["eosdash_port"] == int(
            self.eos_env["EOS_SERVER__EOSDASH_PORT"]
        )


class TestEosdashRedirect:
    """Redirects to EOSdash must target an address the client can reach.

    See https://github.com/Akkudoktor-EOS/EOS/issues/1320: the redirect was built from
    the EOSdash bind address, so remote clients were sent to their own localhost.
    """

    @pytest.fixture
    def client(self, config_eos):
        from fastapi.testclient import TestClient

        from akkudoktoreos.server.eos import app

        config_eos.server.eosdash_host = "127.0.0.1"
        config_eos.server.eosdash_port = 8504
        return TestClient(app, follow_redirects=False)

    @pytest.mark.parametrize("host", ["localhost:8503", "127.0.0.1:8503"])
    def test_root_redirect_uses_request_host(self, client, host):
        """The root redirect points to the host the client used, not to the bind address."""
        response = client.get("/", headers={"Host": host})
        assert response.status_code == HTTPStatus.SEE_OTHER
        assert response.headers["location"] == f"http://{host.split(':')[0]}:8504/"

    def test_root_redirect_uses_host_ip_of_the_eos_machine(self, client):
        """Access by the IP address of the EOS machine redirects to that address."""
        host_ip = get_host_ip()
        response = client.get("/", headers={"Host": f"{host_ip}:8503"})
        assert response.status_code == HTTPStatus.SEE_OTHER
        assert response.headers["location"] == f"http://{host_ip}:8504/"

    def test_root_redirect_ignores_untrusted_forwarded_headers(self, client):
        """Raw forwarding headers cannot override the public dashboard address."""
        response = client.get(
            "/",
            headers={
                "Host": "localhost",
                "X-Forwarded-Host": "eos.example.com",
                "X-Forwarded-Proto": "https",
            },
        )
        assert response.status_code == HTTPStatus.SEE_OTHER
        assert response.headers["location"] == "http://localhost:8504/"

    def test_root_redirect_keeps_local_host(self, client):
        """Local access still redirects to the local EOSdash."""
        response = client.get("/", headers={"Host": "127.0.0.1:8503"})
        assert response.status_code == HTTPStatus.SEE_OTHER
        assert response.headers["location"] == "http://127.0.0.1:8504/"

    def test_untrusted_request_host_is_not_reflected(self, client):
        """An unknown Host header must not become the redirect target."""
        response = client.get("/", headers={"Host": "attacker.example"})
        assert response.status_code == HTTPStatus.NOT_FOUND
        assert "attacker.example:8504" not in response.text
        assert "eosdash_public_url" in response.text

    def test_untrusted_request_host_on_unknown_path(self, client):
        """The 404 page offers no link for an unknown Host header."""
        response = client.get("/no-such-page", headers={"Host": "attacker.example"})
        assert response.status_code == HTTPStatus.NOT_FOUND
        assert "attacker.example:8504" not in response.text

    def test_eosdash_path_redirect_keeps_path(self, client):
        """The path is preserved when redirecting to EOSdash."""
        response = client.get("/eosdash/health", headers={"Host": "localhost:8503"})
        assert response.status_code == HTTPStatus.SEE_OTHER
        assert response.headers["location"] == "http://localhost:8504/eosdash/health"

    def test_unknown_path_error_page_links_to_request_host(self, client):
        """The 404 page links to EOSdash on the host the client used."""
        response = client.get("/no-such-page", headers={"Host": "localhost:8503"})
        assert response.status_code == HTTPStatus.NOT_FOUND
        # The link must be real HTML, the error page escapes the message it is given.
        assert "&lt;a href" not in response.text
        # Compare the whole link target, a substring check would also accept a foreign host.
        hrefs = [href for href in re.findall(r'href="([^"]*)"', response.text) if href != "/docs"]
        assert hrefs == ["http://localhost:8504/"]

    def test_error_page_escapes_request_url(self, client):
        """A crafted URL is shown as text, never as markup."""
        response = client.get(
            "/%3Cscript%3Ealert(1)%3C/script%3E", headers={"Host": "localhost:8503"}
        )
        assert response.status_code == HTTPStatus.NOT_FOUND
        assert "<script>alert(1)</script>" not in response.text

    @pytest.mark.parametrize("host", ["[::1]", "[::1]:8503"])
    def test_direct_ipv6_preserves_address(self, client, host):
        """An IPv6 address keeps its brackets in the redirect."""
        response = client.get("/", headers={"Host": host})
        assert response.headers["location"] == "http://[::1]:8504/"

    def test_untrusted_ipv6_host_is_not_reflected(self, client):
        """An IPv6 address that the configuration does not know is not reflected."""
        response = client.get("/", headers={"Host": "[2001:db8::1234]:8503"})
        assert response.status_code == HTTPStatus.NOT_FOUND
        assert "2001:db8::1234" not in response.headers.get("location", "")

    @pytest.mark.parametrize(
        "public_url",
        [
            "https://energy.example.com",
            "https://energy.example.com:443",
            "https://energy.example.com:9443/dashboard",
            "https://[2001:db8::1234]/dashboard",
        ],
    )
    def test_public_url_preserves_proxy_port_and_prefix(self, client, config_eos, public_url):
        config_eos.server.eosdash_public_url = public_url + "/"
        headers = {"Host": "internal:8503", "X-Forwarded-Host": "wrong.example"}
        response = client.get("/", headers=headers)
        assert response.headers["location"] == public_url + "/"
        response = client.get("/eosdash/health", headers=headers)
        assert response.headers["location"] == public_url + "/eosdash/health"
        response = client.get("/missing", headers=headers)
        hrefs = [href for href in re.findall(r'href="([^"]*)"', response.text) if href != "/docs"]
        assert hrefs == [public_url + "/"]

    @pytest.mark.parametrize(
        "value",
        [
            "",
            "/dashboard",
            "//example.com",
            "ftp://example.com",
            "https://user:password@example.com",
            "https://example.com?token=a",
            "https://example.com#fragment",
            "https://example.com:99999",
            "https://example.com:0",
            "https://example.com\\evil",
            "https://example.com/\nheader",
            "https://example.com/a b",
        ],
    )
    def test_invalid_public_url_rejected(self, config_eos, value):
        with pytest.raises(ValueError):
            config_eos.server.eosdash_public_url = value