-- Run this explicitly through -*- Lua -*-

local lua_bin, inst_share_path, inst_bin_path, inst_mod_path, input_name, output_name = ...

local input_fh = assert(io.open(input_name, "r"))
local output_fh = assert(io.open(output_name, "w"))

local line = input_fh:read "*l"

if not inst_mod_path:match("%?") then
   inst_mod_path = inst_mod_path .. "/?.lua"
   inst_mod_path = inst_mod_path:gsub("/+", "/")
end

local mod_path_present = false
for path_elem in package.path:gmatch("([^;]+)") do
   if path_elem == inst_mod_path then
      mod_path_present = true
      break
   end
end

while line do
   local token = line:match("^%-%- @@(.+)$")
   if token then
      if token == "SHEBANG" then
	 output_fh:write(("#!%s\n"):format(lua_bin))
      elseif token == "GITANO_LUA_PATH" then
	 if not mod_path_present then
	    output_fh:write(("package.path = ('%%s;%%s'):" ..
			     "format(%q, package.path)" ..
				"\n"):format(inst_mod_path))
	 else
	    output_fh:write("-- Gitano modules installed into " ..
			    inst_mod_path .. "\n")
	 end
      elseif token == "GITANO_BIN_PATH" then
	 output_fh:write(("gitano.config.lib_bin_path(%q)\n"):format(inst_bin_path))
      elseif token == "GITANO_SHARE_PATH" then
	 output_fh:write(("gitano.config.share_path(%q)\n"):format(inst_share_path))
      else
	 output_fh:write("-- Unknown token: " .. token .. "\n")
      end
   else
      output_fh:write(line .. "\n")
   end
   line = input_fh:read "*l"
end