"======================================================================
"
" locator.vim - 
"
" Created by skywind on 2024/02/20
" Last Modified: 2024/02/20 21:02:29
"
"======================================================================


"----------------------------------------------------------------------
" initialize
"----------------------------------------------------------------------
let s:windows = has('win32') || has('win64') || has('win16') || has('win95')


"----------------------------------------------------------------------
" special buffer
"----------------------------------------------------------------------
function! asyncrun#locator#special_buffer_path() abort
	if &bt != ''
		return ''
	endif
	let name = bufname('%')
	if name =~ '\v^fugitive\:[\\\/][\\\/][\\\/]'
		let path = strpart(name, s:windows? 12 : 11)
		let pos = stridx(path, '.git')
		if pos >= 0
			let path = strpart(path, 0, pos)
		endif
		return fnamemodify(path, ':h')
	elseif name =~ '^diffview:\/\/'
		let part = strpart(name, 11)
		let pos = stridx(part, '/.git/:')
		if pos > 0
			return strpart(part, 0, pos)
		endif
	endif
	return ''
endfunc


"----------------------------------------------------------------------
" guess current buffer's directory
"----------------------------------------------------------------------
function! asyncrun#locator#nofile_buffer_path() abort
	if &bt == ''
		return ''
	elseif &bt == 'nofile'
		if &ft == 'floggraph'
			if exists('b:flog_state')
				return get(b:flog_state, 'workdir', '')
			endif
		elseif &ft == 'agit_stat' || &ft == 'agit_diff'
			if exists('t:git')
				if has_key(t:git, 'git_root')
					return t:git['git_root']
				endif
			endif
		elseif &ft == 'magit'
			if exists('b:magit_top_dir')
				return b:magit_top_dir
			endif
		elseif &ft == 'NeogitStatus' && has('nvim')
			try
				let t = luaeval('require("neogit.lib.git").repo.git_root')
				return t
			catch
			endtry
		elseif &ft == 'DiffviewFiles' && has('nvim')
			let t = getline(1)
			if t != '' && isdirectory(t)
				return t
			endif
		elseif &ft == 'tagbar'
			if bufname('%') =~ '\v^__TagBar__\.'
				if exists('t:tagbar_state')
					try
						let t = t:tagbar_state._current.fpath
						return t
					catch
					endtry
				endif
			endif
		elseif &ft == 'vista' || &ft =~ '\v^vista_'
			try
				let t = g:vista.source.fname
				return fnamemodify(t, ':p')
			catch
			endtry
		elseif &ft == 'aerial'
			if exists('b:source_buffer')
				let name = bufname(b:source_buffer)
				return name
			endif
		elseif &ft == 'Outline'
			try
				let t = luaeval("require('outline').current.code.buf")
				return bufname(t)
			catch
				try
					let wid = luaeval("require('symbols-outline').state.code_win")
					let bid = winbufnr(wid)
					return bufname(bid)
				catch
				endtry
			endtry
		elseif &ft == 'NvimTree'
			try
				let t = luaeval('require("nvim-tree.api").tree.get_nodes().absolute_path')
				return t
			catch
			endtry
		elseif &ft == 'defx'
			if exists('b:defx')
				try
					let t = b:defx.paths[0]
					return t
				catch
				endtry
			endif
		elseif &ft == 'fern'
			let t = bufname('%')
			if t =~ '\v^fern\:\/\/\w+\/file\:\/\/'
				let t = matchstr(t, '\v^fern\:\/\/\w+\/file\:\/\/\zs.*\ze\$')
				if t != ''
					return (s:windows)? strpart(t, 1) : t
				endif
			endif
		endif
		if exists('b:git_dir')
			return b:git_dir
		endif
	elseif &bt != ''
		if &ft == 'oil'
			let name = bufname('%')
			if name =~ '\v^oil\:[\\\/][\\\/]'
				let t = strpart(name, s:windows? 7 : 6)
				if s:windows && t =~ '\v^\w[\\\/]'
					let t = strpart(t, 0, 1) . ':' . strpart(t, 1)
				endif
				return t
			endif
		endif
	endif
	return ''
endfunc


"----------------------------------------------------------------------
" root locator
"----------------------------------------------------------------------
function! asyncrun#locator#detect(name)
	if &bt == ''
		return asyncrun#locator#special_buffer_path()
	endif
	let path = asyncrun#locator#nofile_buffer_path()
	if path != '' && (isdirectory(path) || filereadable(path))
		return asyncrun#get_root(path)
	endif
	return ''
endfunc