karabiner switch input method

karabiner.json

{
  "description": "Left Command to Switch Input Source",
  "manipulators": [
    {
      "conditions": [
        {
          "type": "input_source_if",
          "input_sources": [
            {
              "language": "en"
            }
          ]
        }
      ],
      "type": "basic",
      "from": {
        "key_code": "left_command",
        "modifiers": {
          "optional": [
            "any"
          ]
        }
      },
      "to": [
        {
          "key_code": "left_command"
        }
      ],
      "to_if_alone": [
        {
          "select_input_source": {
            "language": "zh-Hant",
            "input_source_id": "com.boshiamy.inputmethod.BoshiamyIMK"
          }
        }
      ]
    },
    {
      "conditions": [
        {
          "type": "input_source_unless",
          "input_sources": [
            {
              "language": "en"
            }
          ]
        }
      ],
      "type": "basic",
      "from": {
        "key_code": "left_command",
        "modifiers": {
          "optional": [
            "any"
          ]
        }
      },
      "to": [
        {
          "key_code": "left_command"
        }
      ],
      "to_if_alone": [
        {
          "select_input_source": {
            "language": "en"
          }
        }
      ]
    }
  ]
}