local orig = {}

local function parse(line)
	local prefix, name = line:match('^([| ]*)(.-)%s*$')
	local _, depth = prefix:gsub('|', '')
	return depth, name
end

local function open_entry()
	local buf = vim.api.nvim_get_current_buf()
	local lnum = vim.fn.line('.')
	local depth, name = parse(vim.fn.getline(lnum))

	local function fallback()
		local rhs = orig[buf] and orig[buf].rhs
		if rhs and rhs ~= '' then
			vim.api.nvim_feedkeys(vim.keycode(rhs), 'n', false)
		end
	end

	if name == '' or name:sub(-1) == '/' or depth == 0 then
		return fallback()
	end

	local parts, cur, top = {}, depth, nil
	for l = lnum - 1, 1, -1 do
		local d, n = parse(vim.fn.getline(l))
		if n ~= '' and d < cur and n:sub(-1) == '/' then
			if d == 0 then
				top = n
				break
			end
			table.insert(parts, 1, n)
			cur = d
		end
	end

	if not top or not top:match('^%a+://') then
		return fallback()
	end

	vim.cmd('edit ' .. vim.fn.fnameescape(top .. table.concat(parts) .. name))
end

local function install(buf)
	local m = vim.fn.maparg('<CR>', 'n', false, true)
	if m.callback then return end
	orig[buf] = m
	vim.keymap.set('n', '<CR>', open_entry, { buffer = buf, silent = true })
end

vim.api.nvim_create_autocmd({ 'BufEnter', 'CursorMoved' }, {
	callback = function(a)
		if vim.bo[a.buf].filetype == 'netrw' and vim.g.netrw_liststyle == 3 then
			install(a.buf)
		end
	end,
})