from src.profile.schemas import UpdateProfileRequest
from uuid import UUID
from src.core.models import Assets
from src.profile.schemas import AssetResponse
from src.profile.schemas import LeaveDetailResponse
from src.core.database import get_async_session
from src.auth.utils import get_current_user
from src.notifications.service import get_user_device_tokens
from src.notifications.fcm import send_fcm
from src.profile.models import Leave, LeaveType, LeaveStatus
from src.auth.schemas import BaseResponse
from sqlalchemy import desc
from sqlalchemy.ext.asyncio.session import AsyncSession
from fastapi.params import Depends
from src.core.models import Users, Teams, Roles, UserTeamsRole
from fastapi import APIRouter, Query, HTTPException, BackgroundTasks
from fastapi.responses import RedirectResponse, JSONResponse
from fastapi import APIRouter, Depends, HTTPException, status
from sqlmodel.ext.asyncio.session import AsyncSession
from src.auth.utils import get_current_user  # adjust path
from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.ext.asyncio import AsyncSession
from sqlmodel import select
import uuid
from src.core.models import Users
from src.profile.schemas import (
    CreateLeaveRequest,
    LeaveResponse,
    ApproveRejectRequest,
)
from sqlalchemy import desc

from datetime import datetime
from src.profile.service import create_leave, mentor_decide_leave


router = APIRouter(prefix="/profile", tags=["Profile"])


@router.post("/request", response_model=LeaveResponse)
async def request_leave_route(
    body: CreateLeaveRequest,
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):
    # convert user_id string -> UUID if needed
    try:
        user_uuid = uuid.UUID(user_id)
    except ValueError:
        raise HTTPException(status_code=400, detail="Invalid user id format")

    leave = await create_leave(session, user_uuid, body)

    return LeaveResponse(
        id=str(leave.id),
        leave_type=leave.leave_type,
        from_date=leave.from_date,
        to_date=leave.to_date,
        days=leave.days,
        reason=leave.reason,
        status=leave.status,
        mentor_id=str(leave.mentor_id),
        lead_id=str(leave.lead_id),
    )


@router.post("/{leave_id}/mentor-decision", response_model=LeaveResponse)
async def mentor_decision_route(
    leave_id: str,
    body: ApproveRejectRequest,
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):
    # validate leave_id + user_id UUIDs
    try:
        leave_uuid = uuid.UUID(leave_id)
        mentor_uuid = uuid.UUID(user_id)
    except ValueError:
        raise HTTPException(status_code=400, detail="Invalid UUID")

    # If rejected, comment must be provided
    if body.status == LeaveStatus.REJECTED and not body.comment:
        raise HTTPException(
            status_code=400,
            detail="Comment is required when rejecting leave",
        )

    try:
        leave = await mentor_decide_leave(session, mentor_uuid, leave_uuid, body)
    except PermissionError as e:
        raise HTTPException(status_code=403, detail=str(e))
    except ValueError as e:
        raise HTTPException(status_code=404, detail=str(e))

    return LeaveResponse(
        id=str(leave.id),
        leave_type=leave.leave_type,
        from_date=leave.from_date,
        to_date=leave.to_date,
        days=leave.days,
        reason=leave.reason,
        status=leave.status,
        mentor_id=str(leave.mentor_id),
        lead_id=str(leave.lead_id),
    )


SICK_LIMIT = 10
CASUAL_LIMIT = 10


@router.get("/balance")
async def get_leave_balance(
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):
    stmt = select(Leave).where(
        Leave.user_id == user_id, Leave.status == LeaveStatus.APPROVED
    )
    results = (await session.exec(stmt)).all()

    sick_used = sum(1 for l in results if l.leave_type == LeaveType.SICK)
    casual_used = sum(1 for l in results if l.leave_type == LeaveType.CASUAL)

    sick_remaining = SICK_LIMIT - sick_used
    casual_remaining = CASUAL_LIMIT - casual_used

    return {
        "code": 200,
        "message": "success",
        "data": {
            "sick_remaining": sick_remaining,
            "casual_remaining": casual_remaining,
        },
    }


@router.get("/balance/{user_id}")
async def get_leave_balance_for_user(
    user_id: str,
    session: AsyncSession = Depends(get_async_session),
):
    stmt = select(Leave).where(
        Leave.user_id == user_id, Leave.status == LeaveStatus.APPROVED
    )
    results = (await session.exec(stmt)).all()

    sick_used = sum(1 for l in results if l.leave_type == LeaveType.SICK)
    casual_used = sum(1 for l in results if l.leave_type == LeaveType.CASUAL)

    sick_remaining = SICK_LIMIT - sick_used
    casual_remaining = CASUAL_LIMIT - casual_used

    return {
        "code": 200,
        "message": "success",
        "data": {
            "sick_remaining": sick_remaining,
            "casual_remaining": casual_remaining,
        },
    }


@router.get("/notifications")
async def list_notifications(
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):

    stmt = (
        select(Leave)
        .where(
            (Leave.user_id == user_id)
            | (Leave.mentor_id == user_id)
            | (Leave.lead_id == user_id)
        )
        .order_by(desc(Leave.updated_at))
    )

    results = (await session.exec(stmt)).all()

    notifications = []

    for leave in results:
        if leave.user_id == user_id:
            # user = leave owner
            title = f"Your leave was {leave.status}"
            body = f"{leave.leave_type} from {leave.from_date} to {leave.to_date}"
        elif leave.mentor_id == user_id:
            # mentor receives new leave request
            title = "New Leave Request"
            body = f"{leave.leave_type} requested by user"
        elif leave.lead_id == user_id:
            # lead receives updates
            title = f"Leave {leave.status}"
            body = f"{leave.leave_type} for user updated"
        else:
            title = "Leave Update"
            body = leave.reason or ""

        notifications.append(
            {
                "id": str(leave.id),
                "mentor_id": str(leave.mentor_id),
                "lead_id": str(leave.lead_id),
                "title": title,
                "body": body,
                "type": leave.status,
                "updated_at": leave.updated_at.isoformat(),
                "leave_type": leave.leave_type,
                "from_date": str(leave.from_date),
                "to_date": str(leave.to_date),
                "reject_reason": leave.reject_reason,
                "reason": leave.reason,
                "is_read": leave.is_read,
            }
        )

    return {"code": 200, "data": notifications}


@router.get("/leave/{leave_id}", response_model=LeaveDetailResponse)
async def get_leave_details(
    leave_id: str,
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):
    # Join Leave + Users table to get user_name
    stmt = (
        select(Leave, Users.user_name)
        .join(Users, Users.id == Leave.user_id)
        .where(Leave.id == uuid.UUID(leave_id))
    )

    row = (await session.exec(stmt)).first()

    if not row:
        raise HTTPException(status_code=404, detail="Leave not found")

    leave, user_name = row

    return {
        "code": 200,
        "data": {
            "id": str(leave.id),
            "user_id": str(leave.user_id),
            "user_name": user_name,
            "mentor_id": str(leave.mentor_id),
            "lead_id": str(leave.lead_id),
            "leave_type": leave.leave_type,
            "from_date": leave.from_date.isoformat(),
            "to_date": leave.to_date.isoformat(),
            "days": leave.days,
            "reason": leave.reason,
            "status": leave.status,
            "reject_reason": leave.reject_reason,
            "updated_at": leave.updated_at.isoformat() if leave.updated_at else None,
        },
    }


@router.get("/mentor/pending")
async def mentor_pending_leaves(
    session: AsyncSession = Depends(get_async_session),
    mentor_id: str = Depends(get_current_user),
):
    mentor_uuid = uuid.UUID(mentor_id)

    print("🔥 mentor pending called for:", mentor_id)

    mentor_team = (
        await session.exec(
            select(UserTeamsRole).where(UserTeamsRole.user_id == mentor_uuid)
        )
    ).first()

    if not mentor_team:
        raise HTTPException(404, "Mentor has no team")

    team_users = (
        await session.exec(
            select(UserTeamsRole.user_id).where(
                UserTeamsRole.team_id == mentor_team.team_id
            )
        )
    ).all()

    team_user_ids = [u for u in team_users]

    stmt = (
        select(Leave, Users.user_name)
        .join(Users, Users.id == Leave.user_id)
        .where(
            Leave.user_id.in_(team_user_ids),
            Leave.status == LeaveStatus.PENDING,
        )
        .order_by(desc(Leave.updated_at))
    )

    rows = (await session.exec(stmt)).all()

    result = []

    for leave, user_name in rows:
        result.append(
            LeaveResponse(
                id=str(leave.id),
                leave_type=leave.leave_type,
                from_date=leave.from_date.isoformat(),
                to_date=leave.to_date.isoformat(),
                days=leave.days,
                reason=leave.reason,
                status=(
                    leave.status.value
                    if hasattr(leave.status, "value")
                    else leave.status
                ),
                mentor_id=str(leave.mentor_id),
                lead_id=str(leave.lead_id),
                user_name=user_name,
                updated_at=(leave.updated_at.isoformat() if leave.updated_at else None),
            )
        )

    return {"code": 200, "data": result}


@router.get("/my-leaves")
async def my_leave_history(
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):
    stmt = (
        select(Leave, Users.user_name, Users.email_id)
        .join(Users, Users.id == Leave.mentor_id, isouter=True)
        .where(Leave.user_id == uuid.UUID(user_id))
        .order_by(desc(Leave.updated_at))
    )

    rows = (await session.exec(stmt)).all()

    result = []
    for leave, mentor_name, mentor_email in rows:
        result.append(
            {
                "id": str(leave.id),
                "leave_type": leave.leave_type,
                "from_date": leave.from_date.isoformat(),
                "to_date": leave.to_date.isoformat(),
                "days": leave.days,
                "reason": leave.reason,
                "status": leave.status,
                "mentor_name": mentor_name,
                "updated_at": (
                    leave.updated_at.isoformat() if leave.updated_at else None
                ),
            }
        )

    return {"code": 200, "data": result}


@router.get("/mentor/team-leaves")
async def team_leave_history(
    session: AsyncSession = Depends(get_async_session),
    mentor_id: str = Depends(get_current_user),
):
    stmt = (
        select(Leave, Users.user_name)
        .join(Users, Users.id == Leave.user_id)
        .where(Leave.mentor_id == uuid.UUID(mentor_id))
        .order_by(desc(Leave.updated_at))
    )

    rows = (await session.exec(stmt)).all()

    result = []
    for leave, username in rows:
        result.append(
            {
                "id": str(leave.id),
                "user_name": username,
                "leave_type": leave.leave_type,
                "from_date": leave.from_date.isoformat(),
                "to_date": leave.to_date.isoformat(),
                "days": leave.days,
                "reason": leave.reason,
                "status": leave.status,
                "updated_at": (
                    leave.updated_at.isoformat() if leave.updated_at else None
                ),
            }
        )

    return {"code": 200, "data": result}


@router.get("/contacts", response_model=BaseResponse)
async def get_leave_contacts(
    current_user=Depends(get_current_user),
    session: AsyncSession = Depends(get_async_session),
):
    # get_current_user returns a STRING user_id
    user_id = current_user

    if not user_id:
        raise HTTPException(status_code=400, detail="Invalid user token")

    # 1) Get user's team
    stmt = select(UserTeamsRole).where(UserTeamsRole.user_id == user_id)
    ut = (await session.exec(stmt)).first()

    if not ut:
        raise HTTPException(status_code=404, detail="User-Team mapping not found")

    # 2) Get Team Lead role
    lead_role = (
        await session.exec(select(Roles).where(Roles.name == "Team Lead"))
    ).first()

    if not lead_role:
        raise HTTPException(status_code=500, detail="Team Lead role not found")

    # 3) Find Team Lead user in same team
    lead_user = (
        await session.exec(
            select(Users)
            .join(UserTeamsRole)
            .where(UserTeamsRole.team_id == ut.team_id)
            .where(UserTeamsRole.role_id == lead_role.id)
        )
    ).all()

    if not lead_user:
        raise HTTPException(status_code=404, detail="Team lead not found")

    to_email = ", ".join([u.email_id for u in lead_user])

    # 4) HR CC emails
    hr_team = (await session.exec(select(Teams).where(Teams.name == "HR Team"))).first()

    cc = []
    if hr_team:
        hr_users = (
            await session.exec(
                select(Users)
                .join(UserTeamsRole)
                .where(UserTeamsRole.team_id == hr_team.id)
            )
        ).all()

        cc = [str(row.email_id) for row in hr_users]

    return BaseResponse(code=200, message="success", data={"to": to_email, "cc": cc})


@router.get("/details", response_model=BaseResponse)
async def get_profile_details(
    current_user=Depends(get_current_user),
    session: AsyncSession = Depends(get_async_session),
):
    user_id = current_user

    # 1) Get the user
    user = await session.get(Users, user_id)
    if not user:
        raise HTTPException(status_code=404, detail="User not found")

    # 2) Get user's team mapping
    user_team = (
        await session.exec(
            select(UserTeamsRole).where(UserTeamsRole.user_id == user_id)
        )
    ).first()

    if not user_team:
        raise HTTPException(status_code=404, detail="User does not belong to any team")

    # 3) Get team name
    team = await session.get(Teams, user_team.team_id)

    # 4) Find mentor (team lead)
    lead_role = (
        await session.exec(select(Roles).where(Roles.name == "Mentor"))
    ).first()

    mentor_users = (
        await session.exec(
            select(Users)
            .join(UserTeamsRole)
            .where(UserTeamsRole.team_id == user_team.team_id)
            .where(UserTeamsRole.role_id == lead_role.id)
        )
    ).all()

    mentor_names = [u.user_name for u in mentor_users]
    mentor_emails = [u.email_id for u in mentor_users]

    return BaseResponse(
        code=200,
        message="success",
        data={
            "name": user.user_name,
            "email": user.email_id,
            "team_name": team.name,
            "mentor_name": ", ".join(mentor_names),
            "mentor_email": ", ".join(mentor_emails),
            "join_date": user.join_date,
        },
    )


@router.post("/leave/{leave_id}/cancel")
async def cancel_leave(
    leave_id: str,
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):
    leave = await session.get(Leave, uuid.UUID(leave_id))

    if not leave:
        raise HTTPException(status_code=404, detail="Leave not found")

    # User must own this leave
    if str(leave.user_id) != user_id:
        raise HTTPException(status_code=403, detail="Not your leave")

    # Only approved leaves can be cancelled
    if leave.status not in [LeaveStatus.APPROVED, LeaveStatus.PENDING]:
        raise HTTPException(
            status_code=400,
            detail="Only pending or approved leaves can be cancelled",
        )

    # Check if leave date is future
    from datetime import date

    if leave.from_date <= date.today():
        raise HTTPException(
            status_code=400,
            detail="Past or current day leaves cannot be cancelled",
        )

    # Update leave status
    leave.status = LeaveStatus.CANCELLED
    leave.updated_at = datetime.utcnow()
    await session.commit()

    user = await session.get(Users, leave.user_id)

    # Notify mentor
    mentor_tokens = await get_user_device_tokens(session, leave.mentor_id)
    await send_fcm(
        mentor_tokens,
        "Leave Cancelled",
        f"{user.user_name} cancelled their approved leave.",
        {"type": "leave_cancel", "leave_id": str(leave.id)},
    )

    # Notify Team Lead
    lead_tokens = await get_user_device_tokens(session, leave.lead_id)
    await send_fcm(
        lead_tokens,
        "Leave Cancelled",
        f"User {user.user_name} cancelled their approved leave.",
        {"type": "leave_cancel", "leave_id": str(leave.id)},
    )

    return {
        "code": 200,
        "message": "Leave cancelled successfully",
        "data": {
            "id": str(leave.id),
            "status": leave.status,
        },
    }


@router.get("/assets", response_model=BaseResponse)
async def get_profile(
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):
    # Fetch User
    result = await session.exec(select(Users).where(Users.id == UUID(user_id)))
    user = result.first()

    if not user:
        raise HTTPException(status_code=404, detail="User not found")

    # Fetch Assets for logged-in user
    assets_result = await session.exec(select(Assets).where(Assets.user_id == user.id))
    assets = assets_result.all()

    # Convert SQL rows → Pydantic
    assets_dto = [
        AssetResponse(
            id=a.id,
            user_id=a.user_id,
            name=a.name,
            type=a.type,
            status=a.status,
        )
        for a in assets
    ]

    return BaseResponse(
        code=200,
        data={
            "user_id": str(user.id),
            "email": user.email_id,
            "name": user.user_name,
            "assets": assets_dto,
        },
    )


@router.put("/update-profile", response_model=BaseResponse)
async def update_profile(
    body: UpdateProfileRequest,
    session: AsyncSession = Depends(get_async_session),
    user_id: str = Depends(get_current_user),
):
    # Get logged-in user
    user = await session.get(Users, user_id)
    if not user:
        raise HTTPException(status_code=404, detail="User not found")

    # --- Update basic profile fields ---
    if body.name is not None:
        user.user_name = body.name

    if body.email is not None:
        user.email_id = body.email

    if body.dob is not None:
        dob_str = body.dob.replace(".", "-")  # convert dots to dashes
        try:
            user.dob = datetime.strptime(dob_str, "%Y-%m-%d").date()
        except ValueError:
            raise HTTPException(
                status_code=400, detail="DOB must be YYYY-MM-DD or YYYY.MM.DD"
            )

    if body.address is not None:
        user.address = body.address  # ensure DB has this column

    # --- Handle password update ---
    if body.current_password and body.new_password:
        # Check current password matches
        from src.auth.utils import verify_password, hash_password

        if not verify_password(body.current_password, user.password):
            raise HTTPException(
                status_code=400,
                detail="Current password is incorrect",
            )

        # update password
        user.password = hash_password(body.new_password)

    elif body.new_password and not body.current_password:
        raise HTTPException(
            status_code=400,
            detail="Current password is required to set new password",
        )

    # Save
    await session.commit()
    await session.refresh(user)

    # Response matches frontend expectation
    return BaseResponse(
        code=200,
        data={
            "user": {
                "id": str(user.id),
                "name": user.user_name,
                "email": user.email_id,
                "dob": getattr(user, "dob", None),
                "address": getattr(user, "address", None),
            }
        },
    )