"""
Project Locations Router

Handles monitoring locations (NRLs for sound, monitoring points for vibration)
and unit assignments within projects.
"""

from fastapi import APIRouter, Request, Depends, HTTPException, Query
from fastapi.templating import Jinja2Templates
from fastapi.responses import HTMLResponse, JSONResponse
from sqlalchemy.orm import Session
from sqlalchemy import and_, or_
from datetime import datetime
from typing import Optional
import uuid
import json

from backend.database import get_db
from backend.models import (
    Project,
    ProjectType,
    MonitoringLocation,
    UnitAssignment,
    RosterUnit,
    RecordingSession,
)

router = APIRouter(prefix="/api/projects/{project_id}", tags=["project-locations"])
templates = Jinja2Templates(directory="templates")


# ============================================================================
# Monitoring Locations CRUD
# ============================================================================

@router.get("/locations", response_class=HTMLResponse)
async def get_project_locations(
    project_id: str,
    request: Request,
    db: Session = Depends(get_db),
    location_type: Optional[str] = Query(None),
):
    """
    Get all monitoring locations for a project.
    Returns HTML partial with location list.
    """
    project = db.query(Project).filter_by(id=project_id).first()
    if not project:
        raise HTTPException(status_code=404, detail="Project not found")

    query = db.query(MonitoringLocation).filter_by(project_id=project_id)

    # Filter by type if provided
    if location_type:
        query = query.filter_by(location_type=location_type)

    locations = query.order_by(MonitoringLocation.name).all()

    # Enrich with assignment info
    locations_data = []
    for location in locations:
        # Get active assignment
        assignment = db.query(UnitAssignment).filter(
            and_(
                UnitAssignment.location_id == location.id,
                UnitAssignment.status == "active",
            )
        ).first()

        assigned_unit = None
        if assignment:
            assigned_unit = db.query(RosterUnit).filter_by(id=assignment.unit_id).first()

        # Count recording sessions
        session_count = db.query(RecordingSession).filter_by(
            location_id=location.id
        ).count()

        locations_data.append({
            "location": location,
            "assignment": assignment,
            "assigned_unit": assigned_unit,
            "session_count": session_count,
        })

    return templates.TemplateResponse("partials/projects/location_list.html", {
        "request": request,
        "project": project,
        "locations": locations_data,
    })


@router.post("/locations/create")
async def create_location(
    project_id: str,
    request: Request,
    db: Session = Depends(get_db),
):
    """
    Create a new monitoring location within a project.
    """
    project = db.query(Project).filter_by(id=project_id).first()
    if not project:
        raise HTTPException(status_code=404, detail="Project not found")

    form_data = await request.form()

    location = MonitoringLocation(
        id=str(uuid.uuid4()),
        project_id=project_id,
        location_type=form_data.get("location_type"),
        name=form_data.get("name"),
        description=form_data.get("description"),
        coordinates=form_data.get("coordinates"),
        address=form_data.get("address"),
        location_metadata=form_data.get("location_metadata"),  # JSON string
    )

    db.add(location)
    db.commit()
    db.refresh(location)

    return JSONResponse({
        "success": True,
        "location_id": location.id,
        "message": f"Location '{location.name}' created successfully",
    })


@router.put("/locations/{location_id}")
async def update_location(
    project_id: str,
    location_id: str,
    request: Request,
    db: Session = Depends(get_db),
):
    """
    Update a monitoring location.
    """
    location = db.query(MonitoringLocation).filter_by(
        id=location_id,
        project_id=project_id,
    ).first()

    if not location:
        raise HTTPException(status_code=404, detail="Location not found")

    data = await request.json()

    # Update fields if provided
    if "name" in data:
        location.name = data["name"]
    if "description" in data:
        location.description = data["description"]
    if "location_type" in data:
        location.location_type = data["location_type"]
    if "coordinates" in data:
        location.coordinates = data["coordinates"]
    if "address" in data:
        location.address = data["address"]
    if "location_metadata" in data:
        location.location_metadata = data["location_metadata"]

    location.updated_at = datetime.utcnow()

    db.commit()

    return {"success": True, "message": "Location updated successfully"}


@router.delete("/locations/{location_id}")
async def delete_location(
    project_id: str,
    location_id: str,
    db: Session = Depends(get_db),
):
    """
    Delete a monitoring location.
    """
    location = db.query(MonitoringLocation).filter_by(
        id=location_id,
        project_id=project_id,
    ).first()

    if not location:
        raise HTTPException(status_code=404, detail="Location not found")

    # Check if location has active assignments
    active_assignments = db.query(UnitAssignment).filter(
        and_(
            UnitAssignment.location_id == location_id,
            UnitAssignment.status == "active",
        )
    ).count()

    if active_assignments > 0:
        raise HTTPException(
            status_code=400,
            detail="Cannot delete location with active unit assignments. Unassign units first.",
        )

    db.delete(location)
    db.commit()

    return {"success": True, "message": "Location deleted successfully"}


# ============================================================================
# Unit Assignments
# ============================================================================

@router.get("/assignments", response_class=HTMLResponse)
async def get_project_assignments(
    project_id: str,
    request: Request,
    db: Session = Depends(get_db),
    status: Optional[str] = Query("active"),
):
    """
    Get all unit assignments for a project.
    Returns HTML partial with assignment list.
    """
    query = db.query(UnitAssignment).filter_by(project_id=project_id)

    if status:
        query = query.filter_by(status=status)

    assignments = query.order_by(UnitAssignment.assigned_at.desc()).all()

    # Enrich with unit and location details
    assignments_data = []
    for assignment in assignments:
        unit = db.query(RosterUnit).filter_by(id=assignment.unit_id).first()
        location = db.query(MonitoringLocation).filter_by(id=assignment.location_id).first()

        assignments_data.append({
            "assignment": assignment,
            "unit": unit,
            "location": location,
        })

    return templates.TemplateResponse("partials/projects/assignment_list.html", {
        "request": request,
        "project_id": project_id,
        "assignments": assignments_data,
    })


@router.post("/locations/{location_id}/assign")
async def assign_unit_to_location(
    project_id: str,
    location_id: str,
    request: Request,
    db: Session = Depends(get_db),
):
    """
    Assign a unit to a monitoring location.
    """
    location = db.query(MonitoringLocation).filter_by(
        id=location_id,
        project_id=project_id,
    ).first()

    if not location:
        raise HTTPException(status_code=404, detail="Location not found")

    form_data = await request.form()
    unit_id = form_data.get("unit_id")

    # Verify unit exists and matches location type
    unit = db.query(RosterUnit).filter_by(id=unit_id).first()
    if not unit:
        raise HTTPException(status_code=404, detail="Unit not found")

    # Check device type matches location type
    expected_device_type = "sound_level_meter" if location.location_type == "sound" else "seismograph"
    if unit.device_type != expected_device_type:
        raise HTTPException(
            status_code=400,
            detail=f"Unit type '{unit.device_type}' does not match location type '{location.location_type}'",
        )

    # Check if location already has an active assignment
    existing_assignment = db.query(UnitAssignment).filter(
        and_(
            UnitAssignment.location_id == location_id,
            UnitAssignment.status == "active",
        )
    ).first()

    if existing_assignment:
        raise HTTPException(
            status_code=400,
            detail=f"Location already has an active unit assignment ({existing_assignment.unit_id}). Unassign first.",
        )

    # Create new assignment
    assigned_until_str = form_data.get("assigned_until")
    assigned_until = datetime.fromisoformat(assigned_until_str) if assigned_until_str else None

    assignment = UnitAssignment(
        id=str(uuid.uuid4()),
        unit_id=unit_id,
        location_id=location_id,
        project_id=project_id,
        device_type=unit.device_type,
        assigned_until=assigned_until,
        status="active",
        notes=form_data.get("notes"),
    )

    db.add(assignment)
    db.commit()
    db.refresh(assignment)

    return JSONResponse({
        "success": True,
        "assignment_id": assignment.id,
        "message": f"Unit '{unit_id}' assigned to '{location.name}'",
    })


@router.post("/assignments/{assignment_id}/unassign")
async def unassign_unit(
    project_id: str,
    assignment_id: str,
    db: Session = Depends(get_db),
):
    """
    Unassign a unit from a location.
    """
    assignment = db.query(UnitAssignment).filter_by(
        id=assignment_id,
        project_id=project_id,
    ).first()

    if not assignment:
        raise HTTPException(status_code=404, detail="Assignment not found")

    # Check if there are active recording sessions
    active_sessions = db.query(RecordingSession).filter(
        and_(
            RecordingSession.location_id == assignment.location_id,
            RecordingSession.unit_id == assignment.unit_id,
            RecordingSession.status == "recording",
        )
    ).count()

    if active_sessions > 0:
        raise HTTPException(
            status_code=400,
            detail="Cannot unassign unit with active recording sessions. Stop recording first.",
        )

    assignment.status = "completed"
    assignment.assigned_until = datetime.utcnow()

    db.commit()

    return {"success": True, "message": "Unit unassigned successfully"}


# ============================================================================
# Available Units for Assignment
# ============================================================================

@router.get("/available-units", response_class=JSONResponse)
async def get_available_units(
    project_id: str,
    location_type: str = Query(...),
    db: Session = Depends(get_db),
):
    """
    Get list of available units for assignment to a location.
    Filters by device type matching the location type.
    """
    # Determine required device type
    required_device_type = "sound_level_meter" if location_type == "sound" else "seismograph"

    # Get all units of the required type that are deployed and not retired
    all_units = db.query(RosterUnit).filter(
        and_(
            RosterUnit.device_type == required_device_type,
            RosterUnit.deployed == True,
            RosterUnit.retired == False,
        )
    ).all()

    # Filter out units that already have active assignments
    assigned_unit_ids = db.query(UnitAssignment.unit_id).filter(
        UnitAssignment.status == "active"
    ).distinct().all()
    assigned_unit_ids = [uid[0] for uid in assigned_unit_ids]

    available_units = [
        {
            "id": unit.id,
            "device_type": unit.device_type,
            "location": unit.address or unit.location,
            "model": unit.slm_model if unit.device_type == "sound_level_meter" else unit.unit_type,
        }
        for unit in all_units
        if unit.id not in assigned_unit_ids
    ]

    return available_units


# ============================================================================
# NRL-specific endpoints for detail page
# ============================================================================

@router.get("/nrl/{location_id}/sessions", response_class=HTMLResponse)
async def get_nrl_sessions(
    project_id: str,
    location_id: str,
    request: Request,
    db: Session = Depends(get_db),
):
    """
    Get recording sessions for a specific NRL.
    Returns HTML partial with session list.
    """
    from backend.models import RecordingSession, RosterUnit

    sessions = db.query(RecordingSession).filter_by(
        location_id=location_id
    ).order_by(RecordingSession.started_at.desc()).all()

    # Enrich with unit details
    sessions_data = []
    for session in sessions:
        unit = None
        if session.unit_id:
            unit = db.query(RosterUnit).filter_by(id=session.unit_id).first()

        sessions_data.append({
            "session": session,
            "unit": unit,
        })

    return templates.TemplateResponse("partials/projects/session_list.html", {
        "request": request,
        "project_id": project_id,
        "location_id": location_id,
        "sessions": sessions_data,
    })


@router.get("/nrl/{location_id}/files", response_class=HTMLResponse)
async def get_nrl_files(
    project_id: str,
    location_id: str,
    request: Request,
    db: Session = Depends(get_db),
):
    """
    Get data files for a specific NRL.
    Returns HTML partial with file list.
    """
    from backend.models import DataFile, RecordingSession

    # Join DataFile with RecordingSession to filter by location_id
    files = db.query(DataFile).join(
        RecordingSession,
        DataFile.session_id == RecordingSession.id
    ).filter(
        RecordingSession.location_id == location_id
    ).order_by(DataFile.created_at.desc()).all()

    # Enrich with session details
    files_data = []
    for file in files:
        session = None
        if file.session_id:
            session = db.query(RecordingSession).filter_by(id=file.session_id).first()

        files_data.append({
            "file": file,
            "session": session,
        })

    return templates.TemplateResponse("partials/projects/file_list.html", {
        "request": request,
        "project_id": project_id,
        "location_id": location_id,
        "files": files_data,
    })