Initially reported by @hotzeplotz in 0030791:0066865.

1. cleanup quotings

• add an external css file, only if process_markdown is enabled.
• remove the "__qoute()"-part from from MantisMarkdown.php
• fix the test to match the new output without inline styles.

see https://github.com/mantisbt/mantisbt/compare/master...grummbeer:mantisbt:markdown-cleanup-01-quotings

This is related to 0022190 and https://github.com/mantisbt/mantisbt/pull/1004 (especially the last comment about emails and inline-styles).

For decades the opening arrow > has been the generally accepted character to mark a quote, mail clients take care of this and apply their own formatting, so there is no need to add inline styles to a quote.

2. cleanup tables

• add note to Test, because the [link](/) thing makes this test highly dependent on "process_urls", which is not recognized at all.
• remove __doTable()- stuff from MantisMarkdown.php

Parsedown provide a helpfull method where all "marked" elements accessible. Use it.

see https://github.com/mantisbt/mantisbt/compare/master...grummbeer:mantisbt:markdown-cleanup-02-tables

3. cleanup table tests

[link] (/) makes this test highly dependent on "process_urls", but this is not recognized here, "MantisMarkdown::convert_text" does not know anything about it. Testing links should have a separate test, because its not part of the "tableClassDefinition".

• reduce the sample to match more the intended purpose of this test

see https://github.com/mantisbt/mantisbt/compare/master...grummbeer:mantisbt:markdown-cleanup-03-table-test

4. cleanup the blockHeader part

The Tests testHashLetters, testHashNumberAny and testHashLettersAny failing.

• invert the logic, do not search for a valid markdown heading, search for a valid "buglink" instead.
• Change regex to be more generous with the use of colons.
• Add test for the regular expression.

The Tests testHashLetters, testHashNumberAny and testHashLettersAny are successfully again afterward.

todo: Clarify what a valid issue mention is.

| input            | is issue mention     |
|------------------|----------------------|
| `#1`          | true                 |
| `#123 `          | true                 |
| ` #123 `         | true                 |
| `#123 `          | true                 |
| `#123 summary`   | true                 |
| `#123: summary`  | true                 |
| `#123:summary`   | true                 |
| `#123:: summary` | true but should not? |
| `#123summary`    | false                |
| `# 123:summary`  | false                |
| `# summary `     | false                |
| `# 123`          | false                |

Modify the regex to meet the mantis requirements.

see https://github.com/mantisbt/mantisbt/compare/master...grummbeer:mantisbt:markdown-cleanup-04-blockheader

5. cleanup formatting process

• Rearrange the processing. Moving the Markdown part before ON == $s_text, return the result and do not doing further processing.
• Make MantisMarkdown know about the plugin config and process the links and mentions within the parser context
• mark all the methods that make use of $this->processAmpersand() as deprecated, because the output is no loger messed up.
• remove all methods which marked as "deprecated"

Parsedown provides a usefull method called unmarkedText, which make all "unmarked" strings accessible. Seems the right place to process the links.

see https://github.com/mantisbt/mantisbt/compare/master...grummbeer:mantisbt:markdown-cleanup-05-formatting

After that and merging all parts together the whole part looks very nice and its a huge impact for user experience.

The branches are all independent but could make it a cascading series. What do you think about? I am not experienced in contributing, so this may look strange to you, but I have no idea what the right approach is.

todo

• the tests are now failing because MantisMarkdown.php is getting the plugin config using plugin_config_get, which is not available inside the unit tests. Make it possible to pass a configuration to the MantisMarkdown?
• emails still not proceed with markdown. hidden deep inside string_insert_hrefs make a new api function to catch them?
• add prism to raise up the user experience.

Fixing this todos would be a really nice finishing point.