Subject: RFC 8621 Section 4.1.4 test
Content-Type: multipart/mixed; boundary="1"

--1
Content-Type: text/plain
Content-Disposition: inline

A
--1  
Content-Type: multipart/mixed; boundary="2"

--2
Content-Type: multipart/alternative; boundary="3"

--3
Content-Type: multipart/mixed; boundary="4"

--4
Content-Type: text/plain
Content-Disposition: inline

B
--4  
Content-Type: image/jpeg
Content-Disposition: inline

C
--4  
Content-Type: text/plain
Content-Disposition: inline

D
--4--

--3 
Content-Type: multipart/related; boundary="5"

--5
Content-Type: text/html

<html>E</html>
--5  
Content-Type: image/jpeg

F
--5--  

--3-- 

--2   
Content-Type: image/jpeg
Content-Disposition: attachment

G
--2  
Content-Type: application/x-excel

H
--2  
Content-Type: message/rfc822

Subject: J

J
--2--

--1  
Content-Type: text/plain
Content-Disposition: inline

K
--1--

---- EXPECTED STRUCTURE ----{
  "headers_rfc": {
    "subject": {
      "Text": "RFC 8621 Section 4.1.4 test"
    },
    "content_type": {
      "ContentType": {
        "c_type": "multipart",
        "c_subtype": "mixed",
        "attributes": {
          "boundary": "1"
        }
      }
    }
  },
  "html_body": [
    0,
    8,
    13
  ],
  "text_body": [
    0,
    4,
    5,
    6,
    13
  ],
  "attachments": [
    5,
    9,
    10,
    11,
    12
  ],
  "parts": [
    {
      "Text": {
        "headers_rfc": {
          "content_disposition": {
            "ContentType": {
              "c_type": "inline",
              "c_subtype": null,
              "attributes": null
            }
          },
          "content_type": {
            "ContentType": {
              "c_type": "text",
              "c_subtype": "plain",
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": "A"
      }
    },
    {
      "Multipart": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "multipart",
              "c_subtype": "mixed",
              "attributes": {
                "boundary": "2"
              }
            }
          }
        }
      }
    },
    {
      "Multipart": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "multipart",
              "c_subtype": "alternative",
              "attributes": {
                "boundary": "3"
              }
            }
          }
        }
      }
    },
    {
      "Multipart": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "multipart",
              "c_subtype": "mixed",
              "attributes": {
                "boundary": "4"
              }
            }
          }
        }
      }
    },
    {
      "Text": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "text",
              "c_subtype": "plain",
              "attributes": null
            }
          },
          "content_disposition": {
            "ContentType": {
              "c_type": "inline",
              "c_subtype": null,
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": "B"
      }
    },
    {
      "InlineBinary": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "image",
              "c_subtype": "jpeg",
              "attributes": null
            }
          },
          "content_disposition": {
            "ContentType": {
              "c_type": "inline",
              "c_subtype": null,
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": [
          67
        ]
      }
    },
    {
      "Text": {
        "headers_rfc": {
          "content_disposition": {
            "ContentType": {
              "c_type": "inline",
              "c_subtype": null,
              "attributes": null
            }
          },
          "content_type": {
            "ContentType": {
              "c_type": "text",
              "c_subtype": "plain",
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": "D"
      }
    },
    {
      "Multipart": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "multipart",
              "c_subtype": "related",
              "attributes": {
                "boundary": "5"
              }
            }
          }
        }
      }
    },
    {
      "Html": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "text",
              "c_subtype": "html",
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": "<html>E</html>"
      }
    },
    {
      "Binary": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "image",
              "c_subtype": "jpeg",
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": [
          70
        ]
      }
    },
    {
      "Binary": {
        "headers_rfc": {
          "content_disposition": {
            "ContentType": {
              "c_type": "attachment",
              "c_subtype": null,
              "attributes": null
            }
          },
          "content_type": {
            "ContentType": {
              "c_type": "image",
              "c_subtype": "jpeg",
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": [
          71
        ]
      }
    },
    {
      "Binary": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "application",
              "c_subtype": "x-excel",
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": [
          72
        ]
      }
    },
    {
      "Message": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "message",
              "c_subtype": "rfc822",
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": {
          "headers_rfc": {
            "subject": {
              "Text": "J"
            }
          },
          "html_body": [
            0
          ],
          "text_body": [
            0
          ],
          "attachments": [],
          "parts": [
            {
              "Text": {
                "headers_rfc": {
                  "content_type": {
                    "ContentType": {
                      "c_type": "text",
                      "c_subtype": "plain",
                      "attributes": null
                    }
                  }
                },
                "is_encoding_problem": false,
                "body": "J"
              }
            }
          ],
          "structure": {
            "Part": 0
          },
          "offset_header": 781,
          "offset_body": 793,
          "offset_end": 798
        }
      }
    },
    {
      "Text": {
        "headers_rfc": {
          "content_type": {
            "ContentType": {
              "c_type": "text",
              "c_subtype": "plain",
              "attributes": null
            }
          },
          "content_disposition": {
            "ContentType": {
              "c_type": "inline",
              "c_subtype": null,
              "attributes": null
            }
          }
        },
        "is_encoding_problem": false,
        "body": "K"
      }
    }
  ],
  "structure": {
    "List": [
      {
        "Part": 0
      },
      {
        "MultiPart": [
          1,
          [
            {
              "MultiPart": [
                2,
                [
                  {
                    "MultiPart": [
                      3,
                      [
                        {
                          "Part": 4
                        },
                        {
                          "Part": 5
                        },
                        {
                          "Part": 6
                        }
                      ]
                    ]
                  },
                  {
                    "MultiPart": [
                      7,
                      [
                        {
                          "Part": 8
                        },
                        {
                          "Part": 9
                        }
                      ]
                    ]
                  }
                ]
              ]
            },
            {
              "Part": 10
            },
            {
              "Part": 11
            },
            {
              "Part": 12
            }
          ]
        ]
      },
      {
        "Part": 13
      }
    ]
  },
  "offset_header": 0,
  "offset_body": 82,
  "offset_end": 869
}