"""Unit tests for core client.py functions.

Tests the parsing, header building, media extraction, Chrome target detection,
and feature flag update logic — all without requiring network access.
"""

from __future__ import annotations

import copy
from unittest.mock import MagicMock, patch


from twitter_cli.client import (
    FEATURES,
    _best_chrome_target,
    _build_graphql_url,
    _deep_get,
    _extract_cursor,
    _extract_media,
    _parse_int,
    _update_features_from_html,
    TwitterAPIError,
    TwitterClient,
)


# ── _deep_get ────────────────────────────────────────────────────────────

class TestDeepGet:
    def test_nested_dict(self):
        data = {"a": {"b": {"c": 42}}}
        assert _deep_get(data, "a", "b", "c") == 42

    def test_missing_key(self):
        assert _deep_get({"a": 1}, "b") is None

    def test_deeply_missing(self):
        assert _deep_get({"a": {"b": 1}}, "a", "c", "d") is None

    def test_list_access(self):
        data = {"items": [10, 20, 30]}
        assert _deep_get(data, "items", 1) == 20

    def test_list_out_of_bounds(self):
        data = {"items": [10]}
        assert _deep_get(data, "items", 5) is None

    def test_none_input(self):
        assert _deep_get(None, "a") is None

    def test_empty_keys(self):
        data = {"x": 1}
        assert _deep_get(data) == data


# ── _parse_int ───────────────────────────────────────────────────────────

class TestParseInt:
    def test_normal_int(self):
        assert _parse_int(42, 0) == 42

    def test_string_int(self):
        assert _parse_int("123", 0) == 123

    def test_float_string(self):
        assert _parse_int("99.9", 0) == 99

    def test_comma_separated(self):
        assert _parse_int("1,234", 0) == 1234

    def test_empty_string(self):
        assert _parse_int("", 0) == 0

    def test_none(self):
        assert _parse_int(None, -1) == -1

    def test_invalid(self):
        assert _parse_int("abc", 5) == 5


# ── _extract_cursor ──────────────────────────────────────────────────────

class TestExtractCursor:
    def test_bottom_cursor(self):
        content = {"cursorType": "Bottom", "value": "cursor_abc"}
        assert _extract_cursor(content) == "cursor_abc"

    def test_top_cursor_ignored(self):
        content = {"cursorType": "Top", "value": "cursor_top"}
        assert _extract_cursor(content) is None

    def test_no_cursor(self):
        assert _extract_cursor({}) is None


# ── _extract_media ───────────────────────────────────────────────────────

class TestExtractMedia:
    def test_photo(self):
        legacy = {
            "extended_entities": {
                "media": [
                    {
                        "type": "photo",
                        "media_url_https": "https://pbs.twimg.com/img.jpg",
                        "original_info": {"width": 1200, "height": 800},
                    }
                ]
            }
        }
        media = _extract_media(legacy)
        assert len(media) == 1
        assert media[0].type == "photo"
        assert media[0].url == "https://pbs.twimg.com/img.jpg"
        assert media[0].width == 1200

    def test_video_picks_highest_bitrate(self):
        legacy = {
            "extended_entities": {
                "media": [
                    {
                        "type": "video",
                        "media_url_https": "https://pbs.twimg.com/thumb.jpg",
                        "original_info": {"width": 1920, "height": 1080},
                        "video_info": {
                            "variants": [
                                {"content_type": "video/mp4", "bitrate": 832000, "url": "https://low.mp4"},
                                {"content_type": "video/mp4", "bitrate": 2176000, "url": "https://high.mp4"},
                                {"content_type": "application/x-mpegURL", "url": "https://stream.m3u8"},
                            ]
                        },
                    }
                ]
            }
        }
        media = _extract_media(legacy)
        assert len(media) == 1
        assert media[0].type == "video"
        assert media[0].url == "https://high.mp4"

    def test_no_media(self):
        assert _extract_media({}) == []

    def test_animated_gif(self):
        legacy = {
            "extended_entities": {
                "media": [
                    {
                        "type": "animated_gif",
                        "media_url_https": "https://pbs.twimg.com/gif.mp4",
                        "original_info": {"width": 480, "height": 270},
                        "video_info": {
                            "variants": [
                                {"content_type": "video/mp4", "bitrate": 0, "url": "https://gif.mp4"},
                            ]
                        },
                    }
                ]
            }
        }
        media = _extract_media(legacy)
        assert len(media) == 1
        assert media[0].type == "animated_gif"


# ── _build_graphql_url ───────────────────────────────────────────────────

class TestBuildGraphqlUrl:
    def test_basic_url(self):
        url = _build_graphql_url("abc123", "HomeTimeline", {"count": 20}, {"f1": True})
        assert "graphql/abc123/HomeTimeline" in url
        assert "variables=" in url
        assert "features=" in url

    def test_field_toggles(self):
        url = _build_graphql_url("x", "Op", {}, {}, {"toggle": True})
        assert "fieldToggles=" in url

    def test_false_features_omitted_from_url(self):
        """False-valued features should be omitted to keep URL short (avoid 414)."""
        features = {"enabled_flag": True, "disabled_flag": False, "another_enabled": True}
        url = _build_graphql_url("q", "Op", {}, features)
        assert "enabled_flag" in url
        assert "another_enabled" in url
        assert "disabled_flag" not in url

    def test_url_length_with_full_features(self):
        """URL with full FEATURES dict should stay under 8000 chars (server limit)."""
        url = _build_graphql_url(
            "abc123", "SearchTimeline",
            {"rawQuery": "AI agent", "querySource": "typed_query", "product": "Latest", "count": 50},
            FEATURES,
        )
        assert len(url) < 8000, f"URL too long: {len(url)} chars"


# ── _best_chrome_target ──────────────────────────────────────────────────

class TestBestChromeTarget:
    def test_returns_string(self):
        target = _best_chrome_target()
        assert isinstance(target, str)
        assert "chrome" in target

    def test_fallback_when_no_browser_type(self):
        with patch.dict("sys.modules", {"curl_cffi.requests": MagicMock(BrowserType=MagicMock(side_effect=TypeError))}):
            # Force re-evaluation by clearing cached result
            # When BrowserType iteration fails, should still return a fallback
            target = _best_chrome_target()
            assert isinstance(target, str)


# ── _update_features_from_html ───────────────────────────────────────────

class TestUpdateFeaturesFromHtml:
    def test_updates_existing_feature_flags(self):
        """Should update existing FEATURES keys, not add new ones."""
        original = dict(FEATURES)
        try:
            # Use a key that exists in FEATURES
            existing_key = list(FEATURES.keys())[0]
            original_value = FEATURES[existing_key]
            opposite = "false" if original_value else "true"
            html = '"%s":{"value":%s}' % (existing_key, opposite)
            _update_features_from_html(html)
            assert FEATURES[existing_key] != original_value
        finally:
            FEATURES.clear()
            FEATURES.update(original)

    def test_does_not_add_new_keys(self):
        """Should never add keys not already in FEATURES (prevents URL bloat)."""
        original = dict(FEATURES)
        try:
            html = '"responsive_web_brand_new_feature":{"value":true}'
            _update_features_from_html(html)
            assert "responsive_web_brand_new_feature" not in FEATURES
        finally:
            FEATURES.clear()
            FEATURES.update(original)

    def test_handles_empty_html(self):
        _update_features_from_html("")

    def test_handles_malformed_html(self):
        _update_features_from_html("not json at all {{{")


# ── TwitterClient._build_headers ─────────────────────────────────────────

class TestBuildHeaders:
    @patch("twitter_cli.client._get_cffi_session")
    @patch("twitter_cli.client._gen_ct_headers", return_value={})
    def test_required_headers_present(self, mock_ct_headers, mock_session):
        mock_session.return_value = MagicMock()
        mock_session.return_value.get = MagicMock(side_effect=Exception("skip init"))

        client = TwitterClient.__new__(TwitterClient)
        client._auth_token = "test_token"
        client._ct0 = "test_ct0"
        client._cookie_string = None
        client._request_delay = 2.5
        client._max_retries = 3
        client._retry_base_delay = 5.0
        client._max_count = 200
        client._client_transaction = None
        client._ct_init_attempted = True

        headers = client._build_headers("https://x.com/i/api/graphql/test", "GET")

        assert "Authorization" in headers
        assert "Bearer" in headers["Authorization"]
        assert headers["X-Csrf-Token"] == "test_ct0"
        assert headers["X-Twitter-Auth-Type"] == "OAuth2Session"
        assert "User-Agent" in headers
        assert "sec-ch-ua" in headers

    @patch("twitter_cli.client.get_sec_ch_ua_platform", return_value='"Linux"')
    @patch("twitter_cli.client.get_accept_language", return_value="zh-CN,zh;q=0.9,en;q=0.8")
    @patch("twitter_cli.client.get_twitter_client_language", return_value="zh")
    @patch("twitter_cli.client._get_cffi_session")
    @patch("twitter_cli.client._gen_ct_headers", return_value={})
    def test_cookie_string_used_when_available(
        self,
        mock_ct_headers,
        mock_session,
        mock_client_language,
        mock_accept_language,
        mock_platform,
    ):
        mock_session.return_value = MagicMock()
        mock_session.return_value.get = MagicMock(side_effect=Exception("skip"))

        client = TwitterClient.__new__(TwitterClient)
        client._auth_token = "token"
        client._ct0 = "ct0"
        client._cookie_string = "auth_token=x; ct0=y; other=z"
        client._request_delay = 2.5
        client._max_retries = 3
        client._retry_base_delay = 5.0
        client._max_count = 200
        client._client_transaction = None
        client._ct_init_attempted = True

        headers = client._build_headers()
        assert headers["Cookie"] == "auth_token=x; ct0=y; other=z"
        assert headers["X-Twitter-Client-Language"] == "zh"
        assert headers["Accept-Language"] == "zh-CN,zh;q=0.9,en;q=0.8"
        assert headers["sec-ch-ua-platform"] == '"Linux"'


class TestPaginationBehavior:
    def test_continues_when_cursor_advances_without_new_tweets(self):
        client = TwitterClient.__new__(TwitterClient)
        client._request_delay = 0.0
        client._max_count = 200

        responses = iter(
            [
                {"page": 1},
                {"page": 2},
            ]
        )

        def _graphql_get(operation_name, variables, features, field_toggles=None):
            return next(responses)

        def _parse_timeline_response(data, get_instructions):
            if data["page"] == 1:
                return [], "cursor-2"
            return [MagicMock(id="tweet-1")], None

        client._graphql_get = _graphql_get
        client._parse_timeline_response = _parse_timeline_response

        tweets = client._fetch_timeline("HomeTimeline", 1, lambda data: data)

        assert [tweet.id for tweet in tweets] == ["tweet-1"]

    def test_stops_when_cursor_does_not_advance(self):
        client = TwitterClient.__new__(TwitterClient)
        client._request_delay = 0.0
        client._max_count = 200

        calls = []

        def _graphql_get(operation_name, variables, features, field_toggles=None):
            calls.append(variables.get("cursor"))
            return {"page": len(calls)}

        client._graphql_get = _graphql_get
        client._parse_timeline_response = lambda data, get_instructions: ([], "cursor-same")

        tweets = client._fetch_timeline("HomeTimeline", 1, lambda data: data)

        assert tweets == []
        assert calls == [None, "cursor-same"]


# ── TwitterClient._parse_tweet_result ─────────────────────────────────────

class TestParseTweetResult:
    SAMPLE_TWEET_RESULT = {
        "__typename": "Tweet",
        "rest_id": "1234567890",
        "core": {
            "user_results": {
                "result": {
                    "rest_id": "user123",
                    "core": {"name": "Test User", "screen_name": "testuser"},
                    "legacy": {
                        "name": "Test User",
                        "screen_name": "testuser",
                        "verified": False,
                        "profile_image_url_https": "https://img.com/avatar.jpg",
                    },
                    "is_blue_verified": True,
                }
            }
        },
        "legacy": {
            "full_text": "Hello world! This is a test tweet.",
            "created_at": "Sat Mar 08 12:00:00 +0000 2026",
            "favorite_count": 100,
            "retweet_count": 25,
            "reply_count": 5,
            "quote_count": 3,
            "bookmark_count": 10,
            "lang": "en",
            "entities": {"urls": []},
        },
        "views": {"count": "5000"},
    }

    @patch("twitter_cli.client._get_cffi_session")
    @patch("twitter_cli.client._gen_ct_headers", return_value={})
    def test_parses_basic_tweet(self, mock_ct_headers, mock_session):
        mock_session.return_value = MagicMock()
        mock_session.return_value.get = MagicMock(side_effect=Exception("skip"))

        client = TwitterClient.__new__(TwitterClient)
        client._ct_init_attempted = True
        client._client_transaction = None

        tweet = client._parse_tweet_result(copy.deepcopy(self.SAMPLE_TWEET_RESULT))
        assert tweet is not None
        assert tweet.id == "1234567890"
        assert tweet.text == "Hello world! This is a test tweet."
        assert tweet.author.screen_name == "testuser"
        assert tweet.author.verified is True  # is_blue_verified
        assert tweet.metrics.likes == 100
        assert tweet.metrics.views == 5000
        assert tweet.lang == "en"
        assert tweet.is_retweet is False

    @patch("twitter_cli.client._get_cffi_session")
    @patch("twitter_cli.client._gen_ct_headers", return_value={})
    def test_parses_tombstone_returns_none(self, mock_ct_headers, mock_session):
        mock_session.return_value = MagicMock()
        mock_session.return_value.get = MagicMock(side_effect=Exception("skip"))

        client = TwitterClient.__new__(TwitterClient)
        client._ct_init_attempted = True
        client._client_transaction = None

        result = {"__typename": "TweetTombstone"}
        assert client._parse_tweet_result(result) is None

    @patch("twitter_cli.client._get_cffi_session")
    @patch("twitter_cli.client._gen_ct_headers", return_value={})
    def test_parses_visibility_wrapper(self, mock_ct_headers, mock_session):
        mock_session.return_value = MagicMock()
        mock_session.return_value.get = MagicMock(side_effect=Exception("skip"))

        client = TwitterClient.__new__(TwitterClient)
        client._ct_init_attempted = True
        client._client_transaction = None

        wrapped = {
            "__typename": "TweetWithVisibilityResults",
            "tweet": copy.deepcopy(self.SAMPLE_TWEET_RESULT),
        }
        tweet = client._parse_tweet_result(wrapped)
        assert tweet is not None
        assert tweet.id == "1234567890"

    @patch("twitter_cli.client._get_cffi_session")
    @patch("twitter_cli.client._gen_ct_headers", return_value={})
    def test_depth_limit(self, mock_ct_headers, mock_session):
        mock_session.return_value = MagicMock()
        mock_session.return_value.get = MagicMock(side_effect=Exception("skip"))

        client = TwitterClient.__new__(TwitterClient)
        client._ct_init_attempted = True
        client._client_transaction = None

        assert client._parse_tweet_result(self.SAMPLE_TWEET_RESULT, depth=3) is None


# ── TwitterAPIError ──────────────────────────────────────────────────────

class TestTwitterAPIError:
    def test_stores_status_code(self):
        err = TwitterAPIError(429, "Rate limited")
        assert err.status_code == 429
        assert "Rate limited" in str(err)

    def test_is_runtime_error(self):
        err = TwitterAPIError(500, "Server error")
        assert isinstance(err, RuntimeError)


class TestParseUserResult:
    def test_coerces_count_fields_to_int(self):
        user = TwitterClient._parse_user_result(
            {
                "rest_id": "user-1",
                "legacy": {
                    "name": "Alice",
                    "screen_name": "alice",
                    "followers_count": "1,234",
                    "friends_count": "56",
                    "statuses_count": "78.9",
                    "favourites_count": None,
                },
            }
        )

        assert user is not None
        assert user.followers_count == 1234
        assert user.following_count == 56
        assert user.tweets_count == 78
        assert user.likes_count == 0