#! /usr/bin/env ruby
# -*- coding: UTF-8 -*-
#
# Copyright 2012 Jérémy Zurcher <jeremy@asynk.ch>
#
# This file is part of iotas.
#
# iotas is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# iotas is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with iotas.  If not, see <http://www.gnu.org/licenses/>.

#
module Iotas
    #
    class Spin < Room
        #
        def initialize n, o={}
            super n, nil
            #
            @pool       = {}    # per particle class free list
            @world      = {}    # global iotas index
            @sys_fifo   = []    # system particles fifo list
            @app_fifo   = []    # application particles fifo list
            #
            @run = false
            @hibernation    = o['hibernation']||false
            @hibernate_path = 'iotas-hibernate-'+n+'.json'
            @debug_errors   = o[:debug_errors]||o['debug_errors']||false
            @debug_routing  = o[:debug_routing]||o['debug_routing']||false
            #
            if not o.empty?
                o['iotas'].each do |name,iota|
                    Iotas::Room.json_create(iota.merge!('parent'=>self))
                end if o['iotas']
                o['app_fifo'].each do |particle|
                    @app_fifo << Iotas::Particle.json_create(particle.merge!('spin'=>self))
                end if o['app_fifo']
                o['sys_fifo'].each do |particle|
                    @sys_fifo <<  Iotas::Particle.json_create(particle.merge!('spin'=>self))
                end if o['sys_fifo']
            end
        end
        #
        attr_accessor :run, :hibernate_path, :debug_errors, :debug_routing
        #
        def to_json *a
            {
                'kls'           => self.class.name,
                'timestamp'     => Time.now,
                'name'          => @name,
                'hibernation'   => @hibernation,
                'iotas'         => @iotas,
                'sys_fifo'      => @sys_fifo,
                'app_fifo'      => @app_fifo,
                'debug_errors'  => @debug_errors,
                'debug_routing' => @debug_routing
            }.to_json(*a)
        end
        #
        def self.json_create o
            raise Iotas::Exception.new "JSON #{o['kls']} != #{self.name}" if o['kls'] != self.name
            self.new o['name'], o
        end
        #
        def add_to_world iota
            @world[iota.path] = iota
        end
        #
        def search_world path
            @world[path]
        end
        #
        def clear!
            @iotas.clear
            @pool.clear
            @sys_fifo.clear
            @app_fifo.clear
        end
        #
        #
        def release_p p
            # hope there is no circular loop
            while p2=p.merged_shift
                release_p p2
            end
            p.reset!
            ( @pool[p.class] ||= [] ) << p
        end
        #
        def require_p p_kls
            l = @pool[p_kls]
            return p_kls.new if l.nil?
            p = l.pop
            return p_kls.new if p.nil?
            p
        end
        #
        def post_p p
            @app_fifo << p
        end
        #
        def post_sys_p p
            @sys_fifo << p
        end
        #
        def process_sys_p p
            if p.action==Iotas::SYS_ACT_HIBERNATE
                stop!
                hibernate! p[FIELD_HIBERNATE_PATH]
            else
                super p
            end
        end
        #
        def spin!
            @iotas.values.each do |iota| iota.start! end unless @hibernation
            @run = true
            @hibernation = false
            while @run and (@sys_fifo.length>0 or @app_fifo.length>0)
                while @run and @sys_fifo.length>0
                    p = @sys_fifo.shift
                    p.dst.process_sys_p p
                end
                while @run and @app_fifo.length>0
                    p = @app_fifo.shift
                    p.dst.process_p p
                    break
                end
            end
            @iotas.values.each do |iota| iota.stop! end unless @hibernation
        end
        #
        def stop!
            @run=false
        end
        #
        def hibernate! path=nil
            @hibernation = true
            File.open(path||@hibernate_path,'w') do |f| f << JSON.pretty_generate(self) end
        end
        #
        def self.resume! path
            self.json_create JSON.load File.open(path,'r') { |f| f.read }
        end
        #
    end
    #
end
#
# EOF