#!/usr/bin/env lua
local lapp = require "pl.lapp"
local dir = require "pl.dir"
local path = require "pl.path"
local pretty = require "pl.pretty"
local lpeg = require "lpeg"
local args = lapp [[
Finds dependencies from .SRCINFO files and lists them in buildable stages.
]]
local identifier = lpeg.R"az" + lpeg.R"09" + lpeg.S"@+_"
identifier =  identifier * (identifier + lpeg.S".-")^0
local whitespace = lpeg.S" \t"^1
local rest = (1 - lpeg.S"\n")^0
local definition = lpeg.C(identifier) * whitespace * "=" * whitespace * lpeg.C(rest) * "\n"
local subdefinition = whitespace * definition
local emptylines = (whitespace * "\n")^1
local block = lpeg.Ct(lpeg.Ct(definition) * lpeg.Ct(subdefinition)^0)
local thing = block * (emptylines * block)^0
local capture = lpeg.Ct(thing)
for root, dirs, files in dir.walk(".") do
	for _, file in pairs(files) do
		if file == ".SRCINFO" then
			local pathname = path.normpath(path.join(root, file))
			local srcinfo<close> = io.open(pathname)
			local content = srcinfo:read("a") 
			io.write(pathname, " ")
			pretty.dump(capture:match(content))
			print()
			-- From this, find {,make,check}depends and group packages into stages.
		end
	end
end