POC entries

To tell the truth, there are many ledgers like expenses, COGS, payables, Inventory, Purchases, Sales etc, and lots of entries for this. Sometimes if a company has subsidiaries, they use control accounts as well. If you follow cost accountants material, in that, apart from branch entries, most of the control account entries can be used to perfectly represent transactions related to COGS and WIP   

ok, first purchsed raw matrial

Purchases a/c

To Creditor a/c

then raw material is debited to inventory a/c and from there taken to WIP again. 

WIP a/c

To Raw material Inventory a/c

once production is complete and WIP is transfered to Finished goods a/c

By Finished Goods a/c

By Closing WIP a/c

To WIP a/c

closing WIP is added to closing inventory again and this will be again used in the next periods WIP. (Closing WIP is unprocessed WIP)

Then to offset purchases with finished goods in COGS a/c

By COS a/c 

To Inventory a/c 

here COGS will reduce to closing inventory.

No problem. By the way I meant purchases set off with ending inventOry because it holds WIP as well.