Replace Text after, before and between Commas

Please help me. I really need this!!
Text replace after, before and between the commas


AFTER the comma
When i replace Horse, i want to replace just the text after, before and between the commas
Filename: Dog, White Horse, Horse
New Filename: Dog, White Horse, New

BEFORE the comma
When i replace Apple, i want to replace just the text after, before and between the commas
Filename: Apple, Premium, Good Apple Tree
New Filename: New, Premium, Good Apple Tree

BETWEEN the commas
When i replace Succes, i want to replace just the text after, before and between the commas
Filename: Office Jobs, Succes, Succes Jobs
New Filename: Office Jobs, New, Succes Jobs

OTHER example
When i replace White Horse, i want to replace just the text after, before and between the commas
Filename: Beautiful White Horse, Animals, White Horse
New Filename: Beautiful White Horse, Animals, New

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