#!/usr/bin/env lua
require"lib/tokenizer/default"
require"lib/parser/default"
require"lib/deparser"
require"lib/backend/default"

local input,finaloutput,mode,cppopts
mode = {"preprocess","compile","assemble"}
cppopts = "-P -nostdinc -isystem include -traditional-cpp "
local argn = 1
while arg[argn] do
	if arg[argn]:sub(1,1) == "-" then
		-- parse as an option
		local rem = arg[argn]:sub(2)
		while true do
			if rem:sub(1,1) == "E" then		-- preprocess only
				mode = {"preprocess"}
			elseif rem:sub(1,1) == "S" then		-- compile only
				mode = {"preprocess","compile"}
			elseif rem:sub(1,1) == "c" then		-- compile and assemble
				mode = {"preprocess","compile","assemble"}
			elseif rem:sub(1,1) == "o" then		-- output
				if finaloutput then
					print("jwcc: -o can only be specified once")
					os.exit(254)
				end
				if rem:len() > 1 then
					finaloutput = rem:sub(2)
					break
				else
					if not arg[argn+1] then
						print("jwcc: -o requires an option")
						os.exit(254)
					end
					finaloutput = arg[argn+1]
					argn = argn + 1
				end
			elseif rem:sub(1,1) == "D" then
				if rem:lem() > 1 then
					cppopts = cppopts .. "-D "..rem:sub(2).." "
					break
				else
					if not arg[argn+1] then
						print("jwcc: -D requires an option")
						os.exit(254)
					end
					cppopts = cppopts .. "-D "..arg[argn+1].." "
					argn = argn + 1
				end
			elseif rem:sub(1,1) == "I" then
				if rem:lem() > 1 then
					cppopts = cppopts .. "-I "..rem:sub(2).." "
					break
				else
					if not arg[argn+1] then
						print("jwcc: -I requires an option")
						os.exit(254)
					end
					cppopts = cppopts .. "-I "..arg[argn+1].." "
					argn = argn + 1
				end
			elseif rem:len() == 0 then
				break
			else
				print("jwcc: unknown option \""..rem:sub(1,1).."\"")
				os.exit(254)
			end
			rem = rem:sub(2)
		end
	else
		if input then
			print("jwcc: input can only be specified once")
			os.exit(254)
		end
		input = arg[argn]
	end
	argn = argn + 1
end

if not input then
	print("jwcc: no input specified")
	os.exit(254)
end

local output
for k,v in pairs(mode) do
	if v == "preprocess" then
		if input:match("%.c$") then
			if not mode[k+1] and finaloutput then
				output = finaloutput
			else
				output = input:gsub("%.c$", ".i")
			end
			-- do preprocessing
			if os.execute("cpp "..cppopts.." "..input.." "..output) ~= 0 then
				os.exit(1)
			end
			input = output
		end
	elseif v == "compile" then
		if input:match("%.i$") then
			if not mode[k+1] and finaloutput then
				output = finaloutput
			else
				output = input:gsub("%.i$", ".s")
			end
			local f = assert(io.open(input, "r"))
			local insrc = f:read("*all")
			f:close()
			tokenlist = tokenize(insrc)
			parsetree = parse(tokenlist)
			--deparse(parsetree)
			if backend(parsetree, output) then
				os.exit(1)
			end
			input = output
		end
	elseif v == "assemble" then
		if input:match("%.s$") then
			if not mode[k+1] and finaloutput then
				output = finaloutput
			else
				output = input:gsub("%.o$", ".s")
			end
			if os.execute("blarg-elf-as --fatal-warnings -o "..output.." "..input) ~= 0 then
				os.exit(1)
			end
			input = output
		end
	end
end