import { AbstractMesh, Matrix, Vector3, Scene, Engine } from '@babylonjs/core'
import * as statusColors from '../../lib/statusColors'
import { getSensorIdFromMesh } from './sensorHighlight'

export interface SensorOverlayCircle {
  sensorId: string
  left: number
  top: number
  colorHex: string
}

const parseHexColor = (hex: string) => {
  let clean = hex.trim().replace('#', '')
  if (clean.length === 3) {
    clean = clean
      .split('')
      .map(c => c + c)
      .join('')
  }
  const num = parseInt(clean, 16)
  const r = (num >> 16) & 255
  const g = (num >> 8) & 255
  const b = num & 255
  return { r, g, b }
}

export const hexWithAlpha = (hex: string, alpha: number) => {
  const { r, g, b } = parseHexColor(hex)
  return `rgba(${r}, ${g}, ${b}, ${alpha})`
}

export const computeSensorOverlayCircles = (params: {
  scene: Scene
  engine: Engine
  meshes: AbstractMesh[]
  sensorStatusMap?: Record<string, string>
}): SensorOverlayCircle[] => {
  const { scene, engine, meshes, sensorStatusMap } = params
  const camera = scene.activeCamera
  if (!camera) return []
  const viewport = camera.viewport.toGlobal(engine.getRenderWidth(), engine.getRenderHeight())
  const result: SensorOverlayCircle[] = []

  for (const mesh of meshes) {
    const sensorId = getSensorIdFromMesh(mesh)
    if (!sensorId) continue

    const bbox =
      typeof mesh.getHierarchyBoundingVectors === 'function'
        ? mesh.getHierarchyBoundingVectors()
        : {
            min: mesh.getBoundingInfo().boundingBox.minimumWorld,
            max: mesh.getBoundingInfo().boundingBox.maximumWorld,
          }
    const center = bbox.min.add(bbox.max).scale(0.5)

    const projected = Vector3.Project(center, Matrix.Identity(), scene.getTransformMatrix(), viewport)
    if (!projected) continue

    const statusColor = sensorStatusMap?.[sensorId] || statusColors.STATUS_COLOR_NORMAL

    result.push({
      sensorId,
      left: projected.x,
      top: projected.y,
      colorHex: statusColor,
    })
  }

  return result
}