" Return the filename of the note with id `noteId`. If the file is note found,
" then v:false is returned.
function denote#meta#fileFromNoteId(noteId)
	" According to the file-naming scheme, the note id is prefixed with '@@'. If
	" the note id appears at the beginning of the filename, then this prefix is
	" optional. There may exist another field (such as the signature, title, or
	" keywords field) after the note id. These are prefixed with '==', '--', or
	" '__'. If the note id is the last field, then the id is followed by the file
	" extension, e.g., '.md'.
	" (A) First, we get all files that contain the note id as substring.
	" (B) Then we ensure that the note id is followed by another field or by the
	"     file extension.
	let l:files = glob(g:denote_directory .. '/*' .. a:noteId .. '*', 0, v:true)
				\ ->filter('v:val->split("/")[-1] =~ "' .. a:noteId .. '\\(==\\|--\\|__\\|\\.\\)"')
				\ ->filter('v:val->split("/")[-1] =~ "^' .. a:noteId .. '\\|@@' .. a:noteId .. '"')
	return empty(l:files) ? v:false : l:files[0]
endfunction

" Return the note id from the filename. On failure, v:false is returned.
function denote#meta#noteIdFromFile(file)
	return a:file->fnamemodify(':t')->matchstr('@@\zs.\{-\}\ze\(==\|--\|__\|\..\)')
				\ ?? a:file->fnamemodify(':t')->matchstr('^.\{-\}\ze\(==\|--\|__\|\..\)')
				\ ?? v:false
endfunction

" Return the note title from the filename.
function denote#meta#noteTitleFromFile(file)
	return a:file->fnamemodify(':t')->matchstr('--\zs.\{-\}\ze\(==\|@@\|__\|\..\)')->substitute('-', ' ', 'g')
endfunction

" Return the note tags from the filename as a list.
function denote#meta#noteTagsFromFile(file)
	return a:file->fnamemodify(':t')->matchstr('__\zs.\{-\}\ze\(==\|@@\|--\|\..\)')->split('_')
endfunction

" Identifier creation
function denote#meta#identifier_generate()
	return exists('*strftime')
				\ ? strftime('%Y%m%dT%H%M%S')
				\ : rand()
endfunction