Can mongo go driver marshal/unmarshal common key with value of different formats, string and slice of string?

Working with Data Drivers
,
1

I currently have mongo data stored in two forms (specifically for content key) in a collection. Partial sample data shown below:

Format 1.

{
    "type": "text",
    "content": "foobar",
    "extraTextData": "hello text"
}

Format 2

{
    "type": "group",
    "content": [
        {
            "type": "text",
            "content": "grouped-foobar"
        },
        {
            "type": "image",
            "url": "https://abc.jpg"
        },
    ],
    "extraGroupData": "hello group"
}

My attempt to structure this in golang is below.

type C struct {
    Type string `json:"type" bson:"type"`
    Content ???
    *TextC 
    *GroupC
}
type TextC struct {
    ExtraTextData `json:"extraTextData" bson:"extraTextData"`
}
type GroupC struct {
    ExtraGroupData `json:"extraGroupData" bson:"extraGroupData"`
}

I am having issues on how to setup the structure for “content” field that works for both the formats, TextC and GroupC.

Content for GroupC can be array of C like - Content []C
Content for TextC can also be string type.

Can someone please help & give an example on how to tackle this situation?

Apologies in advance, if this is not a place for such questions, I will delete it if that is the case.