#!/bin/lua
local candran = require("candran")
local cmdline = require("lib.cmdline")
local parse = require("lib.lua-parser.parser").parse
local pp = require("lib.lua-parser.pp")

if #arg < 1 then
	print("Candran "..candran.VERSION.." compiler by Reuh")
	print("Usage: "..arg[0].." [options] filenames...")
	print("Use - instead of filenames to read from the standard input. The output file will be named stdin.lua by default.")
	print("Compiler options:")
	print("  dest=\"directory\"  where compiled files should be written")
	print("  out=\"name.lua\"    output filename. By default, will use the same name as the input file with a .lua extension.")
	print("  -print            write to the standard output instead of creating files")
	print("  -preprocess       only run the preprocessor")
	print("  -compile          only run the compiler")
	print("  -parse            only parse the file and prints errors to stdout")
	print("  -ast              (for debugging purposes) only parse the files and dump the AST to stdout")
	print("Default options:")
	for opt, val in pairs(candran.default) do
		if type(val) == "string" then val = val:gsub("\n", "\\n") end
		print(("  %s=%q"):format(opt, val))
	end
	return
end

local args = cmdline(arg)

if arg[#arg] == "-" then
	table.insert(args, io.stdin)
end

for _, file in ipairs(args) do
	-- Read
	local dest, input
	if file == io.stdin then
		dest = args.out or "stdin.lua"

		input = io.read("*a")

		args.chunkname = "stdin"
	else
		dest = args.out or (file:gsub("%.can$", "")..".lua")

		local inputFile, err = io.open(file, "r")
		if not inputFile then
			io.stderr:write("canc: cannot open "..file..": "..err)
			os.exit(1)
		end
		input = inputFile:read("*a")
		inputFile:close()

		args.chunkname = file
	end

	-- Parse-only situations
	if args.parse or args.ast then
		local ast, err = parse(input, args.chunkname)
		if not ast then
			io.stderr:write("canc: "..err.."\n")
			os.exit(1)
		end
		if args.ast then
			pp.dump(ast)
		end
		return
	end

	-- Compile and output
	if args.dest then
		dest = args.dest .. "/" .. dest
	end

	if not args.print then
		print("Compiling "..args.chunkname.." in "..dest)
	end

	local out = input
	if args.preprocess then
		out = candran.preprocess(out, args)
	end
	if args.compile then
		out = candran.compile(out, args)
	end
	if args.compile == nil and args.preprocess == nil then
		out = candran.make(input, args)
	end

	if args.print then
		print(out)
	else
		local outFile, err = io.open(dest, "w")
		if not outFile then
			os.execute("mkdir -p "..dest:gsub("[^/]+%.lua$", ""))
			outFile, err = io.open(dest, "w")
			if not outFile then
				io.stderr:write("canc: cannot open "..dest..": "..err)
				os.exit(1)
			end
		end
		outFile:write(out)
		outFile:close()
	end
end