"""
User accounts and settings serializers for ThrillWiki API v1.

This module contains all serializers related to user account management,
profile settings, preferences, privacy, notifications, and security.
"""

from rest_framework import serializers
from django.contrib.auth import get_user_model
from drf_spectacular.utils import (
    extend_schema_serializer,
    OpenApiExample,
)
from apps.accounts.models import (
    User,
    UserProfile,
    TopList,
    UserNotification,
    NotificationPreference,
)

UserModel = get_user_model()


# === USER PROFILE SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "User Profile Example",
            summary="Complete user profile",
            description="Full user profile with all fields",
            value={
                "user_id": "1234",
                "username": "thrillseeker",
                "email": "user@example.com",
                "first_name": "John",
                "last_name": "Doe",
                "is_active": True,
                "date_joined": "2024-01-01T00:00:00Z",
                "role": "USER",
                "theme_preference": "dark",
                "profile": {
                    "profile_id": "5678",
                    "display_name": "Thrill Seeker",
                    "avatar": "https://example.com/avatars/user.jpg",
                    "pronouns": "they/them",
                    "bio": "Love roller coasters and theme parks!",
                    "twitter": "https://twitter.com/thrillseeker",
                    "instagram": "https://instagram.com/thrillseeker",
                    "youtube": "https://youtube.com/thrillseeker",
                    "discord": "thrillseeker#1234",
                    "coaster_credits": 150,
                    "dark_ride_credits": 45,
                    "flat_ride_credits": 89,
                    "water_ride_credits": 23,
                },
            },
        )
    ]
)
class UserProfileSerializer(serializers.ModelSerializer):
    """Serializer for user profile data."""

    avatar_url = serializers.SerializerMethodField()
    avatar_variants = serializers.SerializerMethodField()

    class Meta:
        model = UserProfile
        fields = [
            "profile_id",
            "display_name",
            "avatar",
            "avatar_url",
            "avatar_variants",
            "pronouns",
            "bio",
            "twitter",
            "instagram",
            "youtube",
            "discord",
            "coaster_credits",
            "dark_ride_credits",
            "flat_ride_credits",
            "water_ride_credits",
        ]
        read_only_fields = ["profile_id", "avatar_url", "avatar_variants"]

    def get_avatar_url(self, obj):
        """Get the avatar URL with fallback to default letter-based avatar."""
        return obj.get_avatar_url()

    def get_avatar_variants(self, obj):
        """Get avatar variants for different use cases."""
        return obj.get_avatar_variants()

    def validate_display_name(self, value):
        """Validate display name uniqueness - now checks User model first."""
        user = self.context["request"].user
        # Check User model for display_name uniqueness (primary location)
        if User.objects.filter(display_name=value).exclude(id=user.id).exists():
            raise serializers.ValidationError("Display name already taken")
        # Also check UserProfile for backward compatibility during transition
        if UserProfile.objects.filter(display_name=value).exclude(user=user).exists():
            raise serializers.ValidationError("Display name already taken")
        return value


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Complete User Example",
            summary="Complete user with profile",
            description="Full user object with embedded profile",
            value={
                "user_id": "1234",
                "username": "thrillseeker",
                "email": "user@example.com",
                "first_name": "John",
                "last_name": "Doe",
                "is_active": True,
                "date_joined": "2024-01-01T00:00:00Z",
                "role": "USER",
                "theme_preference": "dark",
                "profile": {
                    "profile_id": "5678",
                    "display_name": "Thrill Seeker",
                    "avatar": "https://example.com/avatars/user.jpg",
                    "pronouns": "they/them",
                    "bio": "Love roller coasters and theme parks!",
                    "twitter": "https://twitter.com/thrillseeker",
                    "instagram": "https://instagram.com/thrillseeker",
                    "youtube": "https://youtube.com/thrillseeker",
                    "discord": "thrillseeker#1234",
                    "coaster_credits": 150,
                    "dark_ride_credits": 45,
                    "flat_ride_credits": 89,
                    "water_ride_credits": 23,
                },
            },
        )
    ]
)
class CompleteUserSerializer(serializers.ModelSerializer):
    """Complete user serializer with profile data."""

    profile = UserProfileSerializer(read_only=True)

    class Meta:
        model = User
        fields = [
            "user_id",
            "username",
            "email",
            "first_name",
            "last_name",
            "is_active",
            "date_joined",
            "role",
            "theme_preference",
            "profile",
        ]
        read_only_fields = ["user_id", "date_joined", "role"]


# === USER SETTINGS SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "User Preferences Example",
            summary="User preferences and settings",
            description="User's preference settings",
            value={
                "theme_preference": "dark",
                "email_notifications": True,
                "push_notifications": False,
                "privacy_level": "public",
                "show_email": False,
                "show_real_name": True,
                "show_statistics": True,
                "allow_friend_requests": True,
                "allow_messages": True,
            },
        )
    ]
)
class UserPreferencesSerializer(serializers.Serializer):
    """Serializer for user preferences and settings."""

    theme_preference = serializers.ChoiceField(
        choices=User.ThemePreference.choices, help_text="User's theme preference"
    )
    email_notifications = serializers.BooleanField(
        default=True, help_text="Whether to receive email notifications"
    )
    push_notifications = serializers.BooleanField(
        default=False, help_text="Whether to receive push notifications"
    )
    privacy_level = serializers.ChoiceField(
        choices=[
            ("public", "Public"),
            ("friends", "Friends Only"),
            ("private", "Private"),
        ],
        default="public",
        help_text="Profile visibility level",
    )
    show_email = serializers.BooleanField(
        default=False, help_text="Whether to show email on profile"
    )
    show_real_name = serializers.BooleanField(
        default=True, help_text="Whether to show real name on profile"
    )
    show_statistics = serializers.BooleanField(
        default=True, help_text="Whether to show ride statistics on profile"
    )
    allow_friend_requests = serializers.BooleanField(
        default=True, help_text="Whether to allow friend requests"
    )
    allow_messages = serializers.BooleanField(
        default=True, help_text="Whether to allow direct messages"
    )


# === NOTIFICATION SETTINGS SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Notification Settings Example",
            summary="User notification preferences",
            description="Detailed notification settings",
            value={
                "email_notifications": {
                    "new_reviews": True,
                    "review_replies": True,
                    "friend_requests": True,
                    "messages": True,
                    "weekly_digest": False,
                    "new_features": True,
                    "security_alerts": True,
                },
                "push_notifications": {
                    "new_reviews": False,
                    "review_replies": True,
                    "friend_requests": True,
                    "messages": True,
                },
                "in_app_notifications": {
                    "new_reviews": True,
                    "review_replies": True,
                    "friend_requests": True,
                    "messages": True,
                    "system_announcements": True,
                },
            },
        )
    ]
)
class NotificationSettingsSerializer(serializers.Serializer):
    """Serializer for detailed notification settings."""

    class EmailNotificationsSerializer(serializers.Serializer):
        new_reviews = serializers.BooleanField(default=True)
        review_replies = serializers.BooleanField(default=True)
        friend_requests = serializers.BooleanField(default=True)
        messages = serializers.BooleanField(default=True)
        weekly_digest = serializers.BooleanField(default=False)
        new_features = serializers.BooleanField(default=True)
        security_alerts = serializers.BooleanField(default=True)

    class PushNotificationsSerializer(serializers.Serializer):
        new_reviews = serializers.BooleanField(default=False)
        review_replies = serializers.BooleanField(default=True)
        friend_requests = serializers.BooleanField(default=True)
        messages = serializers.BooleanField(default=True)

    class InAppNotificationsSerializer(serializers.Serializer):
        new_reviews = serializers.BooleanField(default=True)
        review_replies = serializers.BooleanField(default=True)
        friend_requests = serializers.BooleanField(default=True)
        messages = serializers.BooleanField(default=True)
        system_announcements = serializers.BooleanField(default=True)

    email_notifications = EmailNotificationsSerializer()
    push_notifications = PushNotificationsSerializer()
    in_app_notifications = InAppNotificationsSerializer()


# === PRIVACY SETTINGS SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Privacy Settings Example",
            summary="User privacy settings",
            description="Detailed privacy and visibility settings",
            value={
                "profile_visibility": "public",
                "show_email": False,
                "show_real_name": True,
                "show_join_date": True,
                "show_statistics": True,
                "show_reviews": True,
                "show_photos": True,
                "show_top_lists": True,
                "allow_friend_requests": True,
                "allow_messages": True,
                "allow_profile_comments": False,
                "search_visibility": True,
                "activity_visibility": "friends",
            },
        )
    ]
)
class PrivacySettingsSerializer(serializers.Serializer):
    """Serializer for privacy and visibility settings."""

    profile_visibility = serializers.ChoiceField(
        choices=[
            ("public", "Public"),
            ("friends", "Friends Only"),
            ("private", "Private"),
        ],
        default="public",
        help_text="Overall profile visibility",
    )
    show_email = serializers.BooleanField(
        default=False, help_text="Show email address on profile"
    )
    show_real_name = serializers.BooleanField(
        default=True, help_text="Show real name on profile"
    )
    show_join_date = serializers.BooleanField(
        default=True, help_text="Show join date on profile"
    )
    show_statistics = serializers.BooleanField(
        default=True, help_text="Show ride statistics on profile"
    )
    show_reviews = serializers.BooleanField(
        default=True, help_text="Show reviews on profile"
    )
    show_photos = serializers.BooleanField(
        default=True, help_text="Show uploaded photos on profile"
    )
    show_top_lists = serializers.BooleanField(
        default=True, help_text="Show top lists on profile"
    )
    allow_friend_requests = serializers.BooleanField(
        default=True, help_text="Allow others to send friend requests"
    )
    allow_messages = serializers.BooleanField(
        default=True, help_text="Allow others to send direct messages"
    )
    allow_profile_comments = serializers.BooleanField(
        default=False, help_text="Allow others to comment on profile"
    )
    search_visibility = serializers.BooleanField(
        default=True, help_text="Allow profile to appear in search results"
    )
    activity_visibility = serializers.ChoiceField(
        choices=[
            ("public", "Public"),
            ("friends", "Friends Only"),
            ("private", "Private"),
        ],
        default="friends",
        help_text="Who can see your activity feed",
    )


# === SECURITY SETTINGS SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Security Settings Example",
            summary="User security settings",
            description="Account security and authentication settings",
            value={
                "two_factor_enabled": False,
                "login_notifications": True,
                "session_timeout": 30,
                "require_password_change": False,
                "last_password_change": "2024-01-01T00:00:00Z",
                "active_sessions": 2,
                "login_history_retention": 90,
            },
        )
    ]
)
class SecuritySettingsSerializer(serializers.Serializer):
    """Serializer for security settings."""

    two_factor_enabled = serializers.BooleanField(
        default=False, help_text="Whether two-factor authentication is enabled"
    )
    login_notifications = serializers.BooleanField(
        default=True, help_text="Send notifications for new logins"
    )
    session_timeout = serializers.IntegerField(
        default=30, min_value=5, max_value=180, help_text="Session timeout in days"
    )
    require_password_change = serializers.BooleanField(
        default=False, help_text="Whether password change is required"
    )
    last_password_change = serializers.DateTimeField(
        read_only=True, help_text="When password was last changed"
    )
    active_sessions = serializers.IntegerField(
        read_only=True, help_text="Number of active sessions"
    )
    login_history_retention = serializers.IntegerField(
        default=90,
        min_value=30,
        max_value=365,
        help_text="How long to keep login history (days)",
    )


# === USER STATISTICS SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "User Statistics Example",
            summary="User activity statistics",
            description="Comprehensive user activity and contribution statistics",
            value={
                "ride_credits": {
                    "coaster_credits": 150,
                    "dark_ride_credits": 45,
                    "flat_ride_credits": 89,
                    "water_ride_credits": 23,
                    "total_credits": 307,
                },
                "contributions": {
                    "park_reviews": 25,
                    "ride_reviews": 87,
                    "photos_uploaded": 156,
                    "top_lists_created": 8,
                    "helpful_votes_received": 342,
                },
                "activity": {
                    "days_active": 45,
                    "last_active": "2024-01-15T10:30:00Z",
                    "average_review_rating": 4.2,
                    "most_reviewed_park": "Cedar Point",
                    "favorite_ride_type": "Roller Coaster",
                },
                "achievements": {
                    "first_review": True,
                    "photo_contributor": True,
                    "top_reviewer": False,
                    "park_explorer": True,
                    "coaster_enthusiast": True,
                },
            },
        )
    ]
)
class UserStatisticsSerializer(serializers.Serializer):
    """Serializer for user statistics and achievements."""

    class RideCreditsSerializer(serializers.Serializer):
        coaster_credits = serializers.IntegerField()
        dark_ride_credits = serializers.IntegerField()
        flat_ride_credits = serializers.IntegerField()
        water_ride_credits = serializers.IntegerField()
        total_credits = serializers.IntegerField()

    class ContributionsSerializer(serializers.Serializer):
        park_reviews = serializers.IntegerField()
        ride_reviews = serializers.IntegerField()
        photos_uploaded = serializers.IntegerField()
        top_lists_created = serializers.IntegerField()
        helpful_votes_received = serializers.IntegerField()

    class ActivitySerializer(serializers.Serializer):
        days_active = serializers.IntegerField()
        last_active = serializers.DateTimeField()
        average_review_rating = serializers.FloatField()
        most_reviewed_park = serializers.CharField()
        favorite_ride_type = serializers.CharField()

    class AchievementsSerializer(serializers.Serializer):
        first_review = serializers.BooleanField()
        photo_contributor = serializers.BooleanField()
        top_reviewer = serializers.BooleanField()
        park_explorer = serializers.BooleanField()
        coaster_enthusiast = serializers.BooleanField()

    ride_credits = RideCreditsSerializer()
    contributions = ContributionsSerializer()
    activity = ActivitySerializer()
    achievements = AchievementsSerializer()


# === TOP LISTS SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Top List Example",
            summary="User's top list",
            description="A user's ranked list of rides or parks",
            value={
                "id": 1,
                "title": "My Top 10 Roller Coasters",
                "category": "RC",
                "description": "My favorite roller coasters from around the world",
                "created_at": "2024-01-01T00:00:00Z",
                "updated_at": "2024-01-15T10:30:00Z",
                "items_count": 10,
            },
        )
    ]
)
class TopListSerializer(serializers.ModelSerializer):
    """Serializer for user's top lists."""

    items_count = serializers.SerializerMethodField()

    class Meta:
        model = TopList
        fields = [
            "id",
            "title",
            "category",
            "description",
            "created_at",
            "updated_at",
            "items_count",
        ]
        read_only_fields = ["id", "created_at", "updated_at"]

    def get_items_count(self, obj):
        """Get the number of items in the list."""
        return obj.items.count()


# === ACCOUNT UPDATE SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Account Update Example",
            summary="Update account information",
            description="Update basic account information",
            value={
                "first_name": "John",
                "last_name": "Doe",
                "email": "newemail@example.com",
            },
        )
    ]
)
class AccountUpdateSerializer(serializers.ModelSerializer):
    """Serializer for updating account information."""

    class Meta:
        model = User
        fields = [
            "first_name",
            "last_name",
            "email",
        ]

    def validate_email(self, value):
        """Validate email uniqueness."""
        user = self.context["request"].user
        if User.objects.filter(email=value).exclude(id=user.id).exists():
            raise serializers.ValidationError("Email already in use")
        return value


# === PROFILE UPDATE SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Profile Update Example",
            summary="Update profile information",
            description="Update profile information and social links",
            value={
                "display_name": "New Display Name",
                "pronouns": "they/them",
                "bio": "Updated bio text",
                "twitter": "https://twitter.com/newhandle",
                "instagram": "",
                "youtube": "https://youtube.com/newchannel",
                "discord": "newhandle#5678",
            },
        )
    ]
)
class ProfileUpdateSerializer(serializers.ModelSerializer):
    """Serializer for updating profile information."""

    class Meta:
        model = UserProfile
        fields = [
            "display_name",
            "pronouns",
            "bio",
            "twitter",
            "instagram",
            "youtube",
            "discord",
        ]

    def validate_display_name(self, value):
        """Validate display name uniqueness - now checks User model first."""
        user = self.context["request"].user
        # Check User model for display_name uniqueness (primary location)
        if User.objects.filter(display_name=value).exclude(id=user.id).exists():
            raise serializers.ValidationError("Display name already taken")
        # Also check UserProfile for backward compatibility during transition
        if UserProfile.objects.filter(display_name=value).exclude(user=user).exists():
            raise serializers.ValidationError("Display name already taken")
        return value


# === THEME PREFERENCE SERIALIZER ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Theme Update Example",
            summary="Update theme preference",
            description="Update user's theme preference",
            value={
                "theme_preference": "dark",
            },
        )
    ]
)
class ThemePreferenceSerializer(serializers.ModelSerializer):
    """Serializer for updating theme preference."""

    class Meta:
        model = User
        fields = ["theme_preference"]


# === NOTIFICATION SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "User Notification Example",
            summary="User notification",
            description="A notification sent to a user",
            value={
                "id": 1,
                "notification_type": "submission_approved",
                "title": "Your submission has been approved!",
                "message": "Your photo submission for Cedar Point has been approved and is now live on the site.",
                "priority": "normal",
                "is_read": False,
                "read_at": None,
                "created_at": "2024-01-15T10:30:00Z",
                "expires_at": None,
                "extra_data": {"submission_id": 123, "park_name": "Cedar Point"},
            },
        )
    ]
)
class UserNotificationSerializer(serializers.ModelSerializer):
    """Serializer for user notifications."""

    class Meta:
        model = UserNotification
        fields = [
            "id",
            "notification_type",
            "title",
            "message",
            "priority",
            "is_read",
            "read_at",
            "created_at",
            "expires_at",
            "extra_data",
        ]
        read_only_fields = [
            "id",
            "notification_type",
            "title",
            "message",
            "priority",
            "created_at",
            "expires_at",
            "extra_data",
        ]


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Notification Preferences Example",
            summary="User notification preferences",
            description="Comprehensive notification preferences for all channels",
            value={
                "submission_approved_email": True,
                "submission_approved_push": True,
                "submission_approved_inapp": True,
                "submission_rejected_email": True,
                "submission_rejected_push": True,
                "submission_rejected_inapp": True,
                "submission_pending_email": False,
                "submission_pending_push": False,
                "submission_pending_inapp": True,
                "review_reply_email": True,
                "review_reply_push": True,
                "review_reply_inapp": True,
                "review_helpful_email": False,
                "review_helpful_push": True,
                "review_helpful_inapp": True,
                "friend_request_email": True,
                "friend_request_push": True,
                "friend_request_inapp": True,
                "friend_accepted_email": False,
                "friend_accepted_push": True,
                "friend_accepted_inapp": True,
                "message_received_email": True,
                "message_received_push": True,
                "message_received_inapp": True,
                "system_announcement_email": True,
                "system_announcement_push": False,
                "system_announcement_inapp": True,
                "account_security_email": True,
                "account_security_push": True,
                "account_security_inapp": True,
                "feature_update_email": True,
                "feature_update_push": False,
                "feature_update_inapp": True,
                "achievement_unlocked_email": False,
                "achievement_unlocked_push": True,
                "achievement_unlocked_inapp": True,
                "milestone_reached_email": False,
                "milestone_reached_push": True,
                "milestone_reached_inapp": True,
            },
        )
    ]
)
class NotificationPreferenceSerializer(serializers.ModelSerializer):
    """Serializer for notification preferences."""

    class Meta:
        model = NotificationPreference
        fields = [
            # Submission notifications
            "submission_approved_email",
            "submission_approved_push",
            "submission_approved_inapp",
            "submission_rejected_email",
            "submission_rejected_push",
            "submission_rejected_inapp",
            "submission_pending_email",
            "submission_pending_push",
            "submission_pending_inapp",
            # Review notifications
            "review_reply_email",
            "review_reply_push",
            "review_reply_inapp",
            "review_helpful_email",
            "review_helpful_push",
            "review_helpful_inapp",
            # Social notifications
            "friend_request_email",
            "friend_request_push",
            "friend_request_inapp",
            "friend_accepted_email",
            "friend_accepted_push",
            "friend_accepted_inapp",
            "message_received_email",
            "message_received_push",
            "message_received_inapp",
            # System notifications
            "system_announcement_email",
            "system_announcement_push",
            "system_announcement_inapp",
            "account_security_email",
            "account_security_push",
            "account_security_inapp",
            "feature_update_email",
            "feature_update_push",
            "feature_update_inapp",
            # Achievement notifications
            "achievement_unlocked_email",
            "achievement_unlocked_push",
            "achievement_unlocked_inapp",
            "milestone_reached_email",
            "milestone_reached_push",
            "milestone_reached_inapp",
        ]


# === NOTIFICATION ACTIONS SERIALIZERS ===


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Mark Notifications Read Example",
            summary="Mark notifications as read",
            description="Mark specific notifications as read",
            value={"notification_ids": [1, 2, 3, 4, 5]},
        )
    ]
)
class MarkNotificationsReadSerializer(serializers.Serializer):
    """Serializer for marking notifications as read."""

    notification_ids = serializers.ListField(
        child=serializers.IntegerField(),
        help_text="List of notification IDs to mark as read",
    )

    def validate_notification_ids(self, value):
        """Validate that all notification IDs belong to the requesting user."""
        user = self.context["request"].user
        valid_ids = UserNotification.objects.filter(
            id__in=value, user=user
        ).values_list("id", flat=True)

        invalid_ids = set(value) - set(valid_ids)
        if invalid_ids:
            raise serializers.ValidationError(
                f"Invalid notification IDs: {list(invalid_ids)}"
            )

        return value


@extend_schema_serializer(
    examples=[
        OpenApiExample(
            "Avatar Upload Example",
            summary="Upload user avatar",
            description="Upload a new avatar image",
            value={"avatar": "base64_encoded_image_data_or_file_upload"},
        )
    ]
)
class AvatarUploadSerializer(serializers.Serializer):
    """Serializer for uploading user avatar."""

    # Use FileField instead of ImageField to bypass Django's image validation
    avatar = serializers.FileField()

    def validate_avatar(self, value):
        """Validate avatar file."""
        if not value:
            raise serializers.ValidationError("No file provided")

        # Check file size constraints (max 10MB for Cloudflare Images)
        if hasattr(value, 'size') and value.size > 10 * 1024 * 1024:
            raise serializers.ValidationError(
                "Image file too large. Maximum size is 10MB.")

        # Try to validate with PIL
        try:
            from PIL import Image
            import io

            value.seek(0)
            image_data = value.read()
            value.seek(0)  # Reset for later use

            if len(image_data) == 0:
                raise serializers.ValidationError("File appears to be empty")

            # Try to open with PIL
            image = Image.open(io.BytesIO(image_data))

            # Verify it's a valid image
            image.verify()

            # Check image dimensions (max 12,000x12,000 for Cloudflare Images)
            if image.size[0] > 12000 or image.size[1] > 12000:
                raise serializers.ValidationError(
                    "Image dimensions too large. Maximum is 12,000x12,000 pixels.")

            # Check if it's a supported format
            if image.format not in ['JPEG', 'PNG', 'GIF', 'WEBP']:
                raise serializers.ValidationError(
                    f"Unsupported image format: {image.format}. Supported formats: JPEG, PNG, GIF, WebP.")

        except serializers.ValidationError:
            raise  # Re-raise validation errors
        except Exception:
            # PIL validation failed, but let Cloudflare Images try to process it
            pass

        return value