" Maps the % to jump back and forth indentations in Python, almost like jumping
" between brackets in C and Java.
" This might or might not work.
" Antti Kuntsi for the ViM community
"

fun! MoveBackwards(linenum, delta)
	let linenum=a:linenum
	while (getline(linenum)=~"^\s*#")
		let linenum=linenum-a:delta
	endwhile
	return linenum
endfun

fun! FindIndentChange(delta)
	let linenum=nextnonblank(line("."))
	let cind=indent(linenum)
	if (cind==-1)
		return -1
	endif
	while indent(linenum)==cind
		let linenum=linenum+a:delta
		while nextnonblank(linenum)!=linenum || getline(linenum)=~"^\s*#"
			let linenum=linenum+a:delta
			if (linenum>=line("$"))
				return MoveBackwards(line("$"), a:delta)
			endif
		endwhile
	endwhile
	return MoveBackwards(linenum, a:delta)
endfun

fun! FindIndentReduce(delta)
	let linenum=nextnonblank(line("."))
	let cind=indent(linenum)
	if (cind==-1)
		return -1
	endif
	while indent(linenum)>=cind
		let linenum=linenum+a:delta
		while nextnonblank(linenum)!=linenum || getline(linenum)=~"^\s*#"
			let linenum=linenum+a:delta
			if (linenum>=line("$"))
				return MoveBackwards(line("$"), a:delta)
			endif
		endwhile
	endwhile
	return MoveBackwards(linenum-a:delta, a:delta)
endfun

fun! IndentJump()
	let change_line=FindIndentChange(1)
	if (change_line<0)
		return
	endif
	let changed_indent=indent(change_line)
	let new_line=line(".")
	let current_indent=indent(new_line)
	if (changed_indent>current_indent)
		let bytenmbr = line2byte(change_line)
		execute bytenmbr . "goto"
		let new_line=FindIndentReduce(1)
	else
		let new_line=FindIndentReduce(-1)-1
	endif
	if (new_line<0)
		return
	endif
	let bytenmbr = line2byte(prevnonblank(new_line))
	execute bytenmbr . "goto"
	execute "normal _"
endfun

au BufEnter *.py noremap % :call IndentJump()<cr>
au BufLeave *.py unmap %