[LEDGER] Improve readability of HandleChaincodeDeploy

[cendhu]

Type of change

• Improvement (improvement to code)

Description

The following are good examples of avoid disinformation, i.e., context should be explicit in the code itself mentioned in the coding guidelines.

1. if directoryPathArray[3] == "indexes" {
2. if directoryPathArray[3] == "collections" && directoryPathArray[5] == "indexes" {
3. collectionName := directoryPathArray[4]

What is 3, 4, and 5? Hence, we replace the above lines with the following

 indexInfo := getIndexInfo(directoryPath)
 switch {
	case indexInfo.hasIndexForChaincode:
	case indexInfo.hasIndexForCollection:
 }

and followed the most important concept first and the low-level details in the bottom. as per the formatting rules specified in the above coding guidelines. The following may not be a perfect one. However, we try to avoid large code refactoring and restrict ourselves to the ledger package.

        chaincodeIndexDirDepth    = 3
	collectionDirDepth        = 3
	collectionNameDepth       = 4
	collectionIndexDirDepth   = 5

Additional details

These changes were initially part of #966 but we decided to push a separate PR (this one) for the readability related changes.

Related issues

FAB-17739

[manish-sethi]

@cendhu - left you a comment (https://github.com/hyperledger/fabric/pull/1080/files#r409108625)

[manish-sethi]

Merging this one. However, I would like to see two improvements. That can be done in a separate PR

1. Move the constants related to new function, just above the function.
2. Though, not introduced in the PR but just noticed that array element access without checking lengths. A wrong input could cause panic. I recall that you mentioned that you had added that check but not included finally. But, it would be good to check for safety against a bad input.