Diff

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/util/human/io.lua	Wed Sep 30 09:50:33 2020 +0100
@@ -0,0 +1,161 @@
+local array = require "util.array";
+
+local function getchar(n)
+	local stty_ret = os.execute("stty raw -echo 2>/dev/null");
+	local ok, char;
+	if stty_ret == true or stty_ret == 0 then
+		ok, char = pcall(io.read, n or 1);
+		os.execute("stty sane");
+	else
+		ok, char = pcall(io.read, "*l");
+		if ok then
+			char = char:sub(1, n or 1);
+		end
+	end
+	if ok then
+		return char;
+	end
+end
+
+local function getline()
+	local ok, line = pcall(io.read, "*l");
+	if ok then
+		return line;
+	end
+end
+
+local function getpass()
+	local stty_ret, _, status_code = os.execute("stty -echo 2>/dev/null");
+	if status_code then -- COMPAT w/ Lua 5.1
+		stty_ret = status_code;
+	end
+	if stty_ret ~= 0 then
+		io.write("\027[08m"); -- ANSI 'hidden' text attribute
+	end
+	local ok, pass = pcall(io.read, "*l");
+	if stty_ret == 0 then
+		os.execute("stty sane");
+	else
+		io.write("\027[00m");
+	end
+	io.write("\n");
+	if ok then
+		return pass;
+	end
+end
+
+local function show_yesno(prompt)
+	io.write(prompt, " ");
+	local choice = getchar():lower();
+	io.write("\n");
+	if not choice:match("%a") then
+		choice = prompt:match("%[.-(%U).-%]$");
+		if not choice then return nil; end
+	end
+	return (choice == "y");
+end
+
+local function read_password()
+	local password;
+	while true do
+		io.write("Enter new password: ");
+		password = getpass();
+		if not password then
+			print("No password - cancelled");
+			return;
+		end
+		io.write("Retype new password: ");
+		if getpass() ~= password then
+			if not show_yesno [=[Passwords did not match, try again? [Y/n]]=] then
+				return;
+			end
+		else
+			break;
+		end
+	end
+	return password;
+end
+
+local function show_prompt(prompt)
+	io.write(prompt, " ");
+	local line = getline();
+	line = line and line:gsub("\n$","");
+	return (line and #line > 0) and line or nil;
+end
+
+local function printf(fmt, ...)
+	print(fmt:format(...));
+end
+
+local function padright(s, width)
+	return s..string.rep(" ", width-#s);
+end
+
+local function padleft(s, width)
+	return string.rep(" ", width-#s)..s;
+end
+
+local function new_table(col_specs, max_width)
+	max_width = max_width or tonumber(os.getenv("COLUMNS")) or 80;
+	local separator = " | ";
+
+	local widths = {};
+	local total_width = max_width - #separator * (#col_specs-1);
+	local free_width = total_width;
+	-- Calculate width of fixed-size columns
+	for i = 1, #col_specs do
+		local width = col_specs[i].width or "0";
+		if not(type(width) == "string" and width:sub(-1) == "%") then
+			local title = col_specs[i].title;
+			width = math.max(tonumber(width), title and (#title+1) or 0);
+			widths[i] = width;
+			free_width = free_width - width;
+			if i > 1 then
+				free_width = free_width - #separator;
+			end
+		end
+	end
+	-- Calculate width of %-based columns
+	for i = 1, #col_specs do
+		if not widths[i] then
+			local pc_width = tonumber((col_specs[i].width:gsub("%%$", "")));
+			widths[i] = math.floor(free_width*(pc_width/100));
+		end
+	end
+
+	return function (row)
+		local titles;
+		if not row then
+			titles, row = true, array.pluck(col_specs, "title", "");
+		end
+		local output = {};
+		for i, column in ipairs(col_specs) do
+			local width = widths[i];
+			local v = (not titles and column.mapper or tostring)(row[not titles and column.key or i] or "", row);
+			if #v < width then
+				if column.align == "right" then
+					v = padleft(v, width);
+				else
+					v = padright(v, width);
+				end
+			elseif #v > width then
+				v = v:sub(1, width-1) .. "…";
+			end
+			table.insert(output, v);
+		end
+		return table.concat(output, separator);
+	end;
+end
+
+return {
+	getchar = getchar;
+	getline = getline;
+	getpass = getpass;
+	show_yesno = show_yesno;
+	read_password = read_password;
+	show_prompt = show_prompt;
+	printf = printf;
+	padleft = padleft;
+	padright = padright;
+	table = new_table;
+};