added header navigation mappings

diff --git a/ftplugin/mkd.vim b/ftplugin/mkd.vim
new file mode 100644 (file)
index 0000000..0f5d82d
--- /dev/null
+++ b/ftplugin/mkd.vim
@@ -0,0 +1,166 @@
+"TODO get working on visual mode
+
+"- if inside a header
+"    goes to the nearest head before current position
+"    returns its initial hashes (#)
+"- else
+"    goes to beginning of document
+"    returns ''
+fu! b:Markdown_GoCurHeader()
+    if search( '^#', 'bcW' ) != 0
+        return matchstr( getline('.'), '\v^#+' )
+    el
+        norm! gg
+        ec 'outside any header'
+        return ''
+    en
+endf
+
+"same as `b:Markdown_GoCurHeader`:function: but does not change cursor position
+fu! b:Markdown_GetHashesCurHeader()
+    let line = search( '\v^#', 'nW' ) != 0
+    retu matchstr( getline(line) '\v^#+' )
+endf
+
+"goes to next header of any level
+"returns its hashes
+fu! b:Markdown_GoNextHeader()
+    if search( '\v^#', 'W' ) != 0
+        return matchstr( getline('.'), '\v^#+' )
+    el
+        "norm! G
+        ec 'no more headers'
+        return ''
+    en
+endf
+
+"goes to previous header of any level
+"
+"if there is no previous header, only print a warning
+"
+"if the cursor is not exactly at the header,
+"it goes to exactly the header. So this could be used
+"if you want to go to the current header line.
+fu! b:Markdown_GoPreviousHeader()
+    if search( '^#', 'bW' ) != 0
+        return matchstr( getline('.'), '\v^#+' )
+    el
+        "norm! gg
+        ec 'no more headers'
+        return ''
+    en
+endf
+
+"if already at top level, go to beginning of buffer
+fu! b:Markdown_GoHeaderUp()
+    let l:hashes = b:Markdown_GoCurHeader()
+    if len( l:hashes ) > 1
+        cal search( '^' . l:hashes[1:] . '[^#]', 'b' )
+    el
+        norm! gg
+    en
+endf
+
+fu! b:Markdown_GoNextHeaderSameLevel()
+
+    let l:hashes = b:Markdown_GoCurHeader()
+    
+    "go to next occurrence of that number of hashes
+    cal search( '^' . l:hashes . '[^#]', 'W' )
+
+endf
+
+"if no more next siblings, print error message and do nothing.
+fu! b:Markdown_GoNextSiblingHeader()
+
+    let l:hashes = b:Markdown_GoCurHeader()
+
+    if l:hashes ==# ''
+        retu
+    en
+
+    let l:nhashes = len(l:hashes)
+    if l:nhashes == 1
+        "special case, just add the largest possible value
+        let l:nextLowerLevelLine  = line('$') + 1
+    el
+        let l:nextLowerLevelLine  = search( '\v^#{1,' . ( l:nhashes - 1 ) . '}[^#]' , 'nW' )
+    en
+
+    let l:nextSameLevelLine   = search( '\v^' . l:hashes . '[^#]', 'nW' )
+
+    if (
+            \ l:nextSameLevelLine > 0
+            \ &&
+            \ (
+            \   l:nextLowerLevelLine == 0
+            \   ||
+            \   l:nextLowerLevelLine > l:nextSameLevelLine
+            \ )
+        \ )
+        cal cursor( l:nextSameLevelLine, 0 )
+    el
+        ec 'no more siblings'
+    en
+
+endf
+
+fu! b:Markdown_GoPreviousHeaderSameLevel()
+
+    let l:hashes = b:Markdown_GoCurHeader()
+
+    "go to next occurrence of that number of hashes
+    cal search( '^' . l:hashes . '[^#]', 'bW' )
+
+endf
+
+"if no more next siblings, print error message and do nothing.
+fu! b:Markdown_GoPreviousSiblingHeader()
+
+    let l:hashes = b:Markdown_GoCurHeader()
+
+    if l:hashes ==# ''
+        retu
+    en
+
+    let l:nhashes = len(l:hashes)
+    if l:nhashes == 1
+        "special case, just add the largest possible value
+        let l:prevLowerLevelLine  = -1
+    el
+        let l:prevLowerLevelLine  = search( '\v^#{1,' . ( l:nhashes - 1 ) . '}[^#]' , 'bnW' )
+    en
+
+    let l:prevSameLevelLine   = search( '\v^' . l:hashes . '[^#]', 'bnW' )
+
+    if (
+            \ l:prevSameLevelLine > 0
+            \ &&
+            \ (
+            \   l:prevLowerLevelLine == 0
+            \   ||
+            \   l:prevLowerLevelLine < l:prevSameLevelLine
+            \ )
+        \ )
+        cal cursor( l:prevSameLevelLine, 0 )
+    el
+        ec 'no more siblings'
+    en
+
+endf
+
+"mnemonics: ']' next (like a right arrow)
+nn <buffer><silent> ]] :cal b:Markdown_GoNextHeader()<cr>
+"vnoremap <buffer><silent> ]] /^#<cr><esc>:nohl<cr>gv
+
+"mnemonics: '[' next (like a left arrow)
+nn <buffer><silent> ][ :cal b:Markdown_GoNextSiblingHeader()<cr>
+"vnoremap <buffer><silent> ][ <esc>:cal b:Markdown_GoNextHeaderSameLevel()<cr>
+
+nn <buffer><silent> [] :cal b:Markdown_GoPreviousSiblingHeader()<cr>
+
+nn <buffer><silent> [[ :cal b:Markdown_GoPreviousHeader()<cr>
+"vnoremap <buffer><silent> [[ ?^#<cr><esc>:nohl<cr>gv
+
+"go up one level. Menmonic: Up.
+nn <buffer><silent> ]u :cal b:Markdown_GoHeaderUp()<cr>