"""API routes for chat room management

FastAPI router with all room-related endpoints
"""
from fastapi import APIRouter, Depends, HTTPException, status, Query
from sqlalchemy.orm import Session
from typing import List, Optional
from datetime import datetime

from app.core.database import get_db
from app.modules.auth import get_current_user
from app.modules.chat_room import schemas
from app.modules.chat_room.models import MemberRole, RoomStatus
from app.modules.chat_room.services.room_service import room_service
from app.modules.chat_room.services.membership_service import membership_service
from app.modules.chat_room.dependencies import (
    get_current_room,
    require_room_permission,
    validate_room_owner,
    require_admin,
    get_user_effective_role
)
from app.modules.realtime.websocket_manager import manager as ws_manager

router = APIRouter(prefix="/api/rooms", tags=["Chat Rooms"])


# Room CRUD Endpoints
@router.post("", response_model=schemas.RoomResponse, status_code=status.HTTP_201_CREATED)
async def create_room(
    room_data: schemas.CreateRoomRequest,
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Create a new incident room"""
    user_email = current_user["username"]

    room = room_service.create_room(db, user_email, room_data)

    # Get user role for response
    role = membership_service.get_user_role_in_room(db, room.room_id, user_email)

    return schemas.RoomResponse(
        **room.__dict__,
        current_user_role=role,
        is_member=True  # Creator is always a member
    )


@router.get("", response_model=schemas.RoomListResponse)
async def list_rooms(
    status: Optional[RoomStatus] = None,
    incident_type: Optional[schemas.IncidentType] = None,
    severity: Optional[schemas.SeverityLevel] = None,
    search: Optional[str] = None,
    my_rooms: bool = Query(False, description="Filter to show only rooms where user is a member"),
    limit: int = Query(20, ge=1, le=100),
    offset: int = Query(0, ge=0),
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """List all rooms for authenticated user

    Returns all rooms by default. Use my_rooms=true to filter to only rooms
    where the current user is a member. Each room includes is_member and
    current_user_role fields.
    """
    user_email = current_user["username"]
    is_admin = membership_service.is_system_admin(user_email)

    # Create filter params
    filters = schemas.RoomFilterParams(
        status=status,
        incident_type=incident_type,
        severity=severity,
        search=search,
        my_rooms=my_rooms,
        limit=limit,
        offset=offset
    )

    rooms, total = room_service.list_user_rooms(db, user_email, filters, is_admin)

    # Add user role and membership status to each room
    room_responses = []
    for room in rooms:
        role = membership_service.get_user_role_in_room(db, room.room_id, user_email)
        is_member = role is not None
        room_response = schemas.RoomResponse(
            **room.__dict__,
            current_user_role=role,
            is_member=is_member,
            is_admin_view=is_admin
        )
        room_responses.append(room_response)

    return schemas.RoomListResponse(
        rooms=room_responses,
        total=total,
        limit=limit,
        offset=offset
    )


@router.get("/{room_id}", response_model=schemas.RoomResponse)
async def get_room_details(
    room_id: str,
    room = Depends(get_current_room),
    role: Optional[MemberRole] = Depends(get_user_effective_role),
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Get room details including members"""
    # Load members
    members = membership_service.get_room_members(db, room.room_id)
    member_responses = [schemas.MemberResponse.from_orm(m) for m in members]

    is_admin = membership_service.is_system_admin(current_user["username"])
    is_member = role is not None

    return schemas.RoomResponse(
        **room.__dict__,
        members=member_responses,
        current_user_role=role,
        is_member=is_member,
        is_admin_view=is_admin
    )


@router.patch("/{room_id}", response_model=schemas.RoomResponse)
async def update_room(
    room_id: str,
    updates: schemas.UpdateRoomRequest,
    _: None = Depends(require_room_permission("update_metadata")),
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Update room metadata"""
    try:
        room = room_service.update_room(db, room_id, updates)
        if not room:
            raise HTTPException(
                status_code=status.HTTP_404_NOT_FOUND,
                detail="Room not found"
            )

        role = membership_service.get_user_role_in_room(db, room_id, current_user["username"])
        return schemas.RoomResponse(**room.__dict__, current_user_role=role, is_member=True)

    except ValueError as e:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail=str(e)
        )


@router.delete("/{room_id}", response_model=schemas.SuccessResponse)
async def delete_room(
    room_id: str,
    _: None = Depends(validate_room_owner),
    db: Session = Depends(get_db)
):
    """Soft delete (archive) a room"""
    success = room_service.delete_room(db, room_id)
    if not success:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Room not found"
        )

    return schemas.SuccessResponse(message="Room archived successfully")


@router.delete("/{room_id}/permanent", response_model=schemas.SuccessResponse)
async def permanent_delete_room(
    room_id: str,
    _: None = Depends(require_admin),
    db: Session = Depends(get_db)
):
    """Permanently delete a room and all associated data (admin only)

    This is an irreversible operation that deletes:
    - All room members
    - All messages and reactions
    - All uploaded files (including MinIO storage)
    - All generated reports (including MinIO storage)
    - The room itself

    Only system administrators can perform this operation.
    """
    # Broadcast room_deleted event to all connected users BEFORE deleting
    await ws_manager.broadcast_to_room(room_id, {
        "type": "system",
        "event": "room_deleted",
        "room_id": room_id,
        "timestamp": datetime.utcnow().isoformat()
    })

    success, error = room_service.permanent_delete_room(db, room_id)

    if not success:
        if error == "Room not found":
            raise HTTPException(
                status_code=status.HTTP_404_NOT_FOUND,
                detail="Room not found"
            )
        raise HTTPException(
            status_code=status.HTTP_500_INTERNAL_SERVER_ERROR,
            detail=f"Failed to delete room: {error}"
        )

    return schemas.SuccessResponse(message="Room permanently deleted")


# Self-Join Endpoint
@router.post("/{room_id}/join", response_model=schemas.MemberResponse)
async def join_room(
    room_id: str,
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Self-join a room as a viewer

    Any authenticated user can join any non-archived room.
    User will be added with VIEWER role.
    """
    user_email = current_user["username"]

    member, error_code, existing = membership_service.self_join_room(
        db, room_id, user_email
    )

    if error_code == "room_not_found":
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Room not found"
        )
    elif error_code == "room_archived":
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="Cannot join archived room"
        )
    elif error_code == "already_member":
        raise HTTPException(
            status_code=status.HTTP_409_CONFLICT,
            detail={
                "message": "Already a member of this room",
                "current_role": existing.role.value,
                "added_at": existing.added_at.isoformat()
            }
        )

    return schemas.MemberResponse.from_orm(member)


# Membership Endpoints
@router.get("/{room_id}/members", response_model=List[schemas.MemberResponse])
async def list_room_members(
    room_id: str,
    _ = Depends(get_current_room),
    db: Session = Depends(get_db)
):
    """List all members of a room"""
    members = membership_service.get_room_members(db, room_id)
    return [schemas.MemberResponse.from_orm(m) for m in members]


@router.post("/{room_id}/members", response_model=schemas.MemberResponse)
async def add_member(
    room_id: str,
    request: schemas.AddMemberRequest,
    _: None = Depends(require_room_permission("manage_members")),
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Add a member to the room"""
    member = membership_service.add_member(
        db,
        room_id,
        request.user_id,
        request.role,
        current_user["username"]
    )

    if not member:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="User is already a member"
        )

    # Update room activity
    room_service.update_room_activity(db, room_id)

    return schemas.MemberResponse.from_orm(member)


@router.patch("/{room_id}/members/{user_id}", response_model=schemas.MemberResponse)
async def update_member_role(
    room_id: str,
    user_id: str,
    request: schemas.UpdateMemberRoleRequest,
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Update a member's role

    Permission rules:
    - OWNER can change any role
    - EDITOR can upgrade VIEWER → EDITOR only
    - EDITOR cannot downgrade, remove, or set OWNER role
    """
    changer_id = current_user["username"]

    # Get target member's current role
    current_role = membership_service.get_user_role_in_room(db, room_id, user_id)
    if not current_role:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Member not found"
        )

    # Check permission
    allowed, error_msg = membership_service.can_change_member_role(
        db, room_id, changer_id, user_id, current_role, request.role
    )

    if not allowed:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail=error_msg
        )

    member = membership_service.update_member_role(
        db,
        room_id,
        user_id,
        request.role
    )

    if not member:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Member not found"
        )

    # Update room activity
    room_service.update_room_activity(db, room_id)

    return schemas.MemberResponse.from_orm(member)


@router.delete("/{room_id}/members/{user_id}", response_model=schemas.SuccessResponse)
async def remove_member(
    room_id: str,
    user_id: str,
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Remove a member from the room

    Permission rules:
    - OWNER can remove any member
    - EDITOR cannot remove members (only owner can)
    - Users can remove themselves (leave room) unless they're the only owner
    """
    remover_id = current_user["username"]

    # Check permission
    allowed, error_msg = membership_service.can_remove_member(
        db, room_id, remover_id, user_id
    )

    if not allowed:
        raise HTTPException(
            status_code=status.HTTP_403_FORBIDDEN,
            detail=error_msg
        )

    success = membership_service.remove_member(db, room_id, user_id)
    if not success:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Member not found"
        )

    # Update room activity
    room_service.update_room_activity(db, room_id)

    return schemas.SuccessResponse(message="Member removed successfully")


@router.post("/{room_id}/transfer-ownership", response_model=schemas.SuccessResponse)
async def transfer_ownership(
    room_id: str,
    request: schemas.TransferOwnershipRequest,
    _: None = Depends(validate_room_owner),
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Transfer room ownership to another member"""
    success = membership_service.transfer_ownership(
        db,
        room_id,
        current_user["username"],
        request.new_owner_id
    )

    if not success:
        raise HTTPException(
            status_code=status.HTTP_400_BAD_REQUEST,
            detail="New owner must be an existing room member"
        )

    return schemas.SuccessResponse(message="Ownership transferred successfully")


# Permission Endpoints
@router.get("/{room_id}/permissions", response_model=schemas.PermissionResponse)
async def get_user_permissions(
    room_id: str,
    role: Optional[MemberRole] = Depends(get_user_effective_role),
    db: Session = Depends(get_db),
    current_user: dict = Depends(get_current_user)
):
    """Get current user's permissions in the room"""
    user_email = current_user["username"]
    is_admin = membership_service.is_system_admin(user_email)

    if is_admin:
        # Admin has all permissions
        return schemas.PermissionResponse(
            role=role or MemberRole.OWNER,
            is_admin=True,
            can_read=True,
            can_write=True,
            can_manage_members=True,
            can_transfer_ownership=True,
            can_update_status=True,
            can_delete=True
        )

    if not role:
        # Not a member
        return schemas.PermissionResponse(
            role=None,
            is_admin=False,
            can_read=False,
            can_write=False,
            can_manage_members=False,
            can_transfer_ownership=False,
            can_update_status=False,
            can_delete=False
        )

    # Return permissions based on role
    permissions = {
        MemberRole.OWNER: schemas.PermissionResponse(
            role=role,
            is_admin=False,
            can_read=True,
            can_write=True,
            can_manage_members=True,
            can_transfer_ownership=True,
            can_update_status=True,
            can_delete=True
        ),
        MemberRole.EDITOR: schemas.PermissionResponse(
            role=role,
            is_admin=False,
            can_read=True,
            can_write=True,
            can_manage_members=False,
            can_transfer_ownership=False,
            can_update_status=False,
            can_delete=False
        ),
        MemberRole.VIEWER: schemas.PermissionResponse(
            role=role,
            is_admin=False,
            can_read=True,
            can_write=False,
            can_manage_members=False,
            can_transfer_ownership=False,
            can_update_status=False,
            can_delete=False
        )
    }

    return permissions[role]


# LOT Endpoints
@router.post("/{room_id}/lots", response_model=List[str])
async def add_lot(
    room_id: str,
    request: schemas.AddLotRequest,
    _: None = Depends(require_room_permission("update_metadata")),
    db: Session = Depends(get_db)
):
    """Add a LOT batch number to the room"""
    from app.modules.chat_room.models import IncidentRoom

    room = db.query(IncidentRoom).filter(IncidentRoom.room_id == room_id).first()
    if not room:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Room not found")

    # Get current lots or initialize empty list
    current_lots = room.lots or []

    # Prevent duplicates
    if request.lot not in current_lots:
        current_lots.append(request.lot)
        room.lots = current_lots
        room.last_updated_at = datetime.utcnow()
        db.commit()
        db.refresh(room)

    return room.lots


@router.delete("/{room_id}/lots/{lot}", response_model=List[str])
async def remove_lot(
    room_id: str,
    lot: str,
    _: None = Depends(require_room_permission("update_metadata")),
    db: Session = Depends(get_db)
):
    """Remove a LOT batch number from the room"""
    from app.modules.chat_room.models import IncidentRoom

    room = db.query(IncidentRoom).filter(IncidentRoom.room_id == room_id).first()
    if not room:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Room not found")

    current_lots = room.lots or []

    if lot in current_lots:
        current_lots.remove(lot)
        room.lots = current_lots
        room.last_updated_at = datetime.utcnow()
        db.commit()
        db.refresh(room)

    return room.lots