Insert image as 'Place in cell'

[jdugh]

Hi @optilude, nice to retalk with you.

Place in cell features proposal

I have a new PR proposal to propose: Insert image as 'Place in cell', instead of 'Place over cell' as currently proposed with ${image:...}.

The Place in cell allow to place a picture directly 'in the cell' and the image respects the dimensions (and centering) of the cell (without dimension calculation as in the 'over cell'):
https://support.microsoft.com/en-gb/office/insert-picture-in-cell-in-excel-e9317aee-4294-49a3-875c-9dd95845bab0

this feature 'Place in cell' need the feature 'RichData' of MS Excel, I can't find from which version of Excel this feature is available.

So, I propose to add the substitution keyword 'imageincell' (${imageincell:my_json_key}) to use this new functionality : What do you think about the key 'imageincell' ?

What do you think about this PR ? In any case, I will implement this functionality on my side (I need it). I would just like to have your opinion so that I can then give you the PR.

Some pseudo code

If folder xl/richData does not exist, init it with default value;
rdrichvaluestructure.xml and rdRichValueTypes.xml seams to be 'static' files and never change If there are 1 or 5 images.

• Adding the image in the media folder (already available in code).
• richValueRel.xml.rels : Adding the new Relationship with incremental rId and link to image source

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
    <Relationship Id="rId1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/image" Target="../media/image1.jpeg"/>
</Relationships>

• rdrichvalue.xml : increment the count arg of rvData object; adding a 'rv' object with the first 'v' key which has the value {count-1} (I don't know what the 2nd object v corresponds to)

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>   
<rvData xmlns="http://schemas.microsoft.com/office/spreadsheetml/2017/richdata" count="1">   
    <rv s="0">
        <v>0</v>
        <v>5</v>
    </rv>
</rvData>

• richValueRel.xml : Just add the rId of the rels referring to our picture

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<richValueRels xmlns="http://schemas.microsoft.com/office/spreadsheetml/2022/richvaluerel"
    xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">
    <rel r:id="rId1"/>
</richValueRels>

• xl/metadata.xml
  Can be a little complex to control everything 😁
  Increment the count arg of futureMetadata object; adding a 'kb' object
  Increment the count arg of valueMetadata object and adding a 'bk' objet

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<metadata xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"
    xmlns:xlrd="http://schemas.microsoft.com/office/spreadsheetml/2017/richdata">
    <metadataTypes count="1">
        <metadataType name="XLRICHVALUE" minSupportedVersion="120000" copy="1" pasteAll="1" pasteValues="1" merge="1" splitFirst="1" rowColShift="1" clearFormats="1" clearComments="1" assign="1" coerce="1"/>
    </metadataTypes>
    <futureMetadata name="XLRICHVALUE" count="1">
        <bk>
            <extLst>
                <ext uri="{3e2802c4-a4d2-4d8b-9148-e3be6c30e623}">
                    <xlrd:rvb i="0"/>
                </ext>
            </extLst>
        </bk>
    </futureMetadata>
    <valueMetadata count="1">
        <bk>
            <rc t="1" v="0"/>
        </bk>
    </valueMetadata>
</metadata>

• And make unit test !

[kant2002]

Sounds cool. Given that I'm mostly maintain this library, I'm happy take this change if sufficient tests would be present.

[jdugh]

Close with this PR :
#189
#190
#191