# models/schema/message.py
"""
Pydantic schemas for the messaging system.

Supports three communication channels:
- Admin <-> Vendor
- Vendor <-> Customer
- Admin <-> Customer
"""

from datetime import datetime

from pydantic import BaseModel, ConfigDict, Field

from models.database.message import ConversationType, ParticipantType


# ============================================================================
# Attachment Schemas
# ============================================================================


class AttachmentResponse(BaseModel):
    """Schema for message attachment in responses."""

    model_config = ConfigDict(from_attributes=True)

    id: int
    filename: str
    original_filename: str
    file_size: int
    mime_type: str
    is_image: bool
    image_width: int | None = None
    image_height: int | None = None
    download_url: str | None = None
    thumbnail_url: str | None = None

    @property
    def file_size_display(self) -> str:
        """Human-readable file size."""
        if self.file_size < 1024:
            return f"{self.file_size} B"
        elif self.file_size < 1024 * 1024:
            return f"{self.file_size / 1024:.1f} KB"
        else:
            return f"{self.file_size / 1024 / 1024:.1f} MB"


# ============================================================================
# Message Schemas
# ============================================================================


class MessageCreate(BaseModel):
    """Schema for sending a new message."""

    content: str = Field(..., min_length=1, max_length=10000)


class MessageResponse(BaseModel):
    """Schema for a single message in responses."""

    model_config = ConfigDict(from_attributes=True)

    id: int
    conversation_id: int
    sender_type: ParticipantType
    sender_id: int
    content: str
    is_system_message: bool
    is_deleted: bool
    created_at: datetime

    # Enriched sender info (populated by API)
    sender_name: str | None = None
    sender_email: str | None = None

    # Attachments
    attachments: list[AttachmentResponse] = []


# ============================================================================
# Participant Schemas
# ============================================================================


class ParticipantInfo(BaseModel):
    """Schema for participant information."""

    id: int
    type: ParticipantType
    name: str
    email: str | None = None
    avatar_url: str | None = None


class ParticipantResponse(BaseModel):
    """Schema for conversation participant in responses."""

    model_config = ConfigDict(from_attributes=True)

    id: int
    participant_type: ParticipantType
    participant_id: int
    unread_count: int
    last_read_at: datetime | None
    email_notifications: bool
    muted: bool

    # Enriched info (populated by API)
    participant_info: ParticipantInfo | None = None


# ============================================================================
# Conversation Schemas
# ============================================================================


class ConversationCreate(BaseModel):
    """Schema for creating a new conversation."""

    conversation_type: ConversationType
    subject: str = Field(..., min_length=1, max_length=500)
    recipient_type: ParticipantType
    recipient_id: int
    vendor_id: int | None = None
    initial_message: str | None = Field(None, min_length=1, max_length=10000)


class ConversationSummary(BaseModel):
    """Schema for conversation in list views."""

    model_config = ConfigDict(from_attributes=True)

    id: int
    conversation_type: ConversationType
    subject: str
    vendor_id: int | None = None
    is_closed: bool
    closed_at: datetime | None
    last_message_at: datetime | None
    message_count: int
    created_at: datetime

    # Unread count for current user (from participant)
    unread_count: int = 0

    # Other participant info (enriched by API)
    other_participant: ParticipantInfo | None = None

    # Last message preview
    last_message_preview: str | None = None


class ConversationDetailResponse(BaseModel):
    """Schema for full conversation detail with messages."""

    model_config = ConfigDict(from_attributes=True)

    id: int
    conversation_type: ConversationType
    subject: str
    vendor_id: int | None = None
    is_closed: bool
    closed_at: datetime | None
    closed_by_type: ParticipantType | None = None
    closed_by_id: int | None = None
    last_message_at: datetime | None
    message_count: int
    created_at: datetime
    updated_at: datetime

    # Participants with enriched info
    participants: list[ParticipantResponse] = []

    # Messages ordered by created_at
    messages: list[MessageResponse] = []

    # Current user's unread count
    unread_count: int = 0

    # Vendor info if applicable
    vendor_name: str | None = None


class ConversationListResponse(BaseModel):
    """Schema for paginated conversation list."""

    conversations: list[ConversationSummary]
    total: int
    total_unread: int
    skip: int
    limit: int


# ============================================================================
# Unread Count Schemas
# ============================================================================


class UnreadCountResponse(BaseModel):
    """Schema for unread message count (for header badge)."""

    total_unread: int


# ============================================================================
# Notification Preferences Schemas
# ============================================================================


class NotificationPreferencesUpdate(BaseModel):
    """Schema for updating notification preferences."""

    email_notifications: bool | None = None
    muted: bool | None = None


# ============================================================================
# Conversation Action Schemas
# ============================================================================


class CloseConversationResponse(BaseModel):
    """Response after closing a conversation."""

    success: bool
    message: str
    conversation_id: int


class ReopenConversationResponse(BaseModel):
    """Response after reopening a conversation."""

    success: bool
    message: str
    conversation_id: int


class MarkReadResponse(BaseModel):
    """Response after marking conversation as read."""

    success: bool
    conversation_id: int
    unread_count: int


# ============================================================================
# Recipient Selection Schemas (for compose modal)
# ============================================================================


class RecipientOption(BaseModel):
    """Schema for a selectable recipient in compose modal."""

    id: int
    type: ParticipantType
    name: str
    email: str | None = None
    vendor_id: int | None = None  # For vendor users
    vendor_name: str | None = None


class RecipientListResponse(BaseModel):
    """Schema for list of available recipients."""

    recipients: list[RecipientOption]
    total: int


# ============================================================================
# Admin-specific Schemas
# ============================================================================


class AdminConversationSummary(ConversationSummary):
    """Extended conversation summary with vendor info for admin views."""

    vendor_name: str | None = None
    vendor_code: str | None = None


class AdminConversationListResponse(BaseModel):
    """Schema for admin conversation list with vendor info."""

    conversations: list[AdminConversationSummary]
    total: int
    total_unread: int
    skip: int
    limit: int


class AdminMessageStats(BaseModel):
    """Messaging statistics for admin dashboard."""

    total_conversations: int = 0
    open_conversations: int = 0
    closed_conversations: int = 0
    total_messages: int = 0

    # By type
    admin_vendor_conversations: int = 0
    vendor_customer_conversations: int = 0
    admin_customer_conversations: int = 0

    # Unread
    unread_admin: int = 0