Firebase companies and employees data structure

gistfile1.json

{
  companies: {
    cmp0001: {
      name: "Happy company"
      employees: {
        u0001: "admin",
        u0002: "manager"
      }
    },
    cmp0002: {
      name: "Happy company"
      employees: {
        u0001: "assistant",
        u0002: "admin"
      }
    }
  },
  users: {
    u0001: {
      name: "Happy admin"
      companies: {
        cmp0001: "admin",
        cmp0002: "assistant"
      }
    },
    u0002: {
      name: "Happy admin"
      companies: {
        cmp0001: "manager",
        cmp0002: "admin"
      }
    }
  }
}