coding style PSR-12

encapsulate functions into Classes

class FulltextSearch
class MetaSearch

make Doku_Indexer singleton

encapsulate wordlen() in the Indexer

encapsulate idx_get_stopwords()

encapsulate idx_get_version()

encapsulate idx_addPage()

Note: idx_listIndexLengths() is used in iinc/TaskRunner.php and inc/Remote/ApiCore.php file

Also used in _test files.

deprecated idx_lookup()

This function is not called from elsewhere.

deprecated idx_tokenizer()

This function is not called from elsewhere.

deprecated idx_getIndex()

Note: idx_getIndex() is used in inc/infoutils.php file

encapsulate idx_listIndexLengths()

Note: idx_listIndexLengths() is used in inc/infoutils.php file

deprecated idx_indexLengths()

This function is not called from elsewhere.

encapsulate idx_cleanName()

idx_cleanName() was called only from Doku_Indexer::addMetaKeys(), lookupKey(), getPages(), histogram()

coding style

change default of passcrypt to bcrypt #2936

PHP8 fix: string offset out of range due to null

PHP8 fix: Array to string conversion for array_diff_key/assoc

PHP8 fix part 5: Trying to access array offset on value of type bool/null

PHP8 fix part 4: Trying to access array offset on value of type bool/null

PHP8 fix part 3: Trying to access array offset on value of type bool/null

PHP8 fix part 2: Trying to access array offset on value of type bool/null

PHP8 fix part 1: Trying to access array offset on value of type bool/null

Update year 2019 to 2020

Update license links to HTTPS

If the website provides a secure connection, it is better not to rely on correct permanent redirect (HTTP 301) from the insecure one.

Update link to https in welcome message