#!/usr/bin/env ruby
## Distributed under the CC0 public domain license.
## By Alison Watson. Attribution is encouraged, though not required.
## <https://creativecommons.org/publicdomain/zero/1.0/legalcode>
## ZSClassTree: Generates a class tree from ZScript files.
## Example usage:
## tools/zsclasstree.rb \
## '/mnt/g/Archive/gzdoom-g4.1.0/wadsrc/static/zscript/**/*.zs' \
## > trees/tree_g4.1.0.txt

require 'set'

class ClassSiphon
	attr_reader :structs, :classes, :clstree, :strtree, :caps

	def initialize dirs
		@subcls  = {}
		@classes = Set[]
		@structs = Set[]
		@caps    = {}

		Dir.glob dirs do |f| proc_file File.read f end

		@clstree = make_tree "OBJECT", @subcls["OBJECT"]
		@strtree = @structs.map {|type| [type, nil]}

		@classes.freeze
		@structs.freeze
		@clstree.freeze
		@strtree.freeze
		@caps.freeze
	end

	def print_classes out, filter = []
		print_tree out, filter, "OBJECT", clstree
	end

	def print_structs out, filter = []
		print_tree out, filter, "STRUCT", strtree
	end

	private
	def add_class m
		ctype =  m[0]             .strip
		cbase = (m[1] or "Object").strip
		type = ctype.upcase
		base = cbase.upcase
		@caps[type] = ctype
		@caps[base] = cbase

		if base != type
			if @subcls[base]
				@subcls[base] << type
			else
				@subcls[base] = [type]
			end
			raise "duplicate class #{type}" if @classes === type
			@classes << type
		end
	end

	def add_struct m
		ctype = m[0]
		type = ctype.upcase
		@caps[type] = ctype
		@structs << type
	end

	def proc_file f
		f.gsub! /\/\*(?!\*\/)+\*\//m, ""
		f.gsub! /\/\/.+/, ""
		f.scan(/^class\s*(\w*)[\s\w]+(?::\s+(\w*))?/).each {|m| add_class  m}
		f.scan(/^struct\s*(\w*)/)                    .each {|m| add_struct m}
	end

	# work our way down the subclasses recursively, making them into a tree structure
	def make_tree bcl, subs
		return nil unless subs
		node = {}
		subs.each do |cl| node[cl] = make_tree cl, @subcls[cl] end
		node
	end

	def print_tree out, filter, base, tree, tab = ""
		return if !tree or filter.include? base

		tree = tree.map do |type, base| [type, base] end
		tree.sort!

		for type, base in tree
			last = type == tree[-1][0]
			sep = last ? "└ " : "├ "
			nxt = last ? "  " : "│ "

			out.puts tab + sep + @caps[type]

			print_tree out, filter, type, base, tab + nxt
		end
	end
end

if __FILE__ == $0
	in_dirs = ARGV.shift
	filters = ARGV

	si = ClassSiphon.new in_dirs
	puts "Object"; si.print_classes STDOUT, filters
	puts "Struct"; si.print_structs STDOUT, filters
end

## EOF