-- This file is part of Liberty Eiffel.
--
-- Liberty Eiffel is free software: you can redistribute it and/or modify
-- it under the terms of the GNU General Public License as published by
-- the Free Software Foundation, version 3 of the License.
--
-- Liberty Eiffel 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 General Public License for more details.
--
-- You should have received a copy of the GNU General Public License
-- along with Liberty Eiffel.  If not, see <http://www.gnu.org/licenses/>.
--
class LIBERTY_ETC_CLUSTER
   --
   -- A cluster from the master configuration, to be imported if not overridden by the local loadpath.
   --

inherit
   HASHABLE
      redefine
         out_in_tagged_out_memory
      end

insert
   LOGGING
      redefine
         out_in_tagged_out_memory, is_equal
      end

create {LIBERTY_ETC_VISITOR_IMPL}
   make

feature {ANY}
   name: FIXED_STRING
   locations: TRAVERSABLE[FIXED_STRING]
   version: FIXED_STRING
   depth: INTEGER
   cluster: LIBERTY_CLUSTER

   is_equal (other: like Current): BOOLEAN is
      do
         Result := Current = other
      end

   needs: TRAVERSABLE[LIBERTY_ETC_NEEDS] is
      do
         Result := needs_memory
      ensure
         Result /= Void
      end

   hash_code: INTEGER is
      do
         Result := name.hash_code
      end

   out_in_tagged_out_memory is
      local
         i: INTEGER
      do
         tagged_out_memory.append(once "Master cluster %"")
         tagged_out_memory.append(name)
         tagged_out_memory.extend('"')
         if version /= Void then
            tagged_out_memory.append(once " (version ")
            tagged_out_memory.append(version)
            tagged_out_memory.extend(')')
         end
         tagged_out_memory.append(once ": {")
         from
            i := locations.lower
         until
            i > locations.upper
         loop
            if i > locations.lower then
               tagged_out_memory.append(once ", ")
            end
            tagged_out_memory.append(locations.item(i))
            i := i + 1
         end
         tagged_out_memory.append(once "} (depth: ")
         depth.append_in(tagged_out_memory)
         tagged_out_memory.extend(')')
      end

feature {LIBERTY_ETC_VISITOR_IMPL}
   set_version (a_version: like version) is
      require
         version = Void
         a_version /= Void
      do
         version := a_version
      ensure
         version = a_version
      end

   add_needs (a_needs: LIBERTY_ETC_NEEDS) is
      require
         a_needs /= Void
      do
         needs_memory.add_last(a_needs)
      ensure
         needs_memory.fast_has(a_needs)
      end

   check_validity (all_clusters: MAP[LIBERTY_ETC_CLUSTER, FIXED_STRING]) is
      require
         all_clusters /= Void
      do
         needs_memory.do_all(agent {LIBERTY_ETC_NEEDS}.check_validity(all_clusters))
      end

   check_cycles is
      do
         needs_memory.do_all(agent (n: LIBERTY_ETC_NEEDS) is do n.cluster.check_cycle(Current, n) end)
      end

feature {LIBERTY_ETC_CLUSTER}
   check_cycle (a_origin: LIBERTY_ETC_CLUSTER; a_needs: LIBERTY_ETC_NEEDS) is
      require
         a_needs.cluster = Current
      do
         if find_needs_cycle(a_needs, a_origin, Current) then
            log.trace.put_new_line
         end
         clear_cycle_mark
      end

   find_cycle (origin, start: LIBERTY_ETC_CLUSTER): BOOLEAN is
      do
         if mark = 1 then
            Result := start = Current
            if Result then
               if log.is_trace then
                  log.trace.put_string(once "Cycle in ")
                  log.trace.put_string(origin.name)
                  log.trace.put_string(once ": ")
                  log.trace.put_string(name)
               end
            end
         else
            mark := 1
            Result := needs_memory.exists(agent find_needs_cycle(?, origin, start))
            if Result then
               if log.is_trace then
                  log.trace.put_string(once " -> ")
                  log.trace.put_string(name)
               end
            end
         end
         mark := 0
      end

   clear_cycle_mark is
      do
         if mark /= 0 then
            mark := 0
            needs_memory.do_all(agent clear_needs_cycle)
         end
      end

feature {}
   find_needs_cycle (a_needs: LIBERTY_ETC_NEEDS; origin, start: LIBERTY_ETC_CLUSTER): BOOLEAN is
      do
         Result := a_needs.cluster.find_cycle(origin, start)
         if Result then
            a_needs.set_in_cycle
         end
      end

   clear_needs_cycle (a_needs: LIBERTY_ETC_NEEDS) is
      do
         a_needs.cluster.clear_cycle_mark
      end

feature {LIBERTY_ETC_VISITOR_IMPL, LIBERTY_ETC_CLUSTER}
   fix_depth (a_mark: like mark): BOOLEAN is
      require
         a_mark >= mark
      do
         if mark < a_mark then
            mark := a_mark
            if deepen_needs then
               Result := fix_needs_depth
            end
         end
      ensure
         mark = a_mark
      end

   mark: INTEGER

feature {}
   deepen_needs: BOOLEAN is
      local
         i: INTEGER; need: LIBERTY_ETC_NEEDS
      do
         from
            i := needs_memory.lower
         until
            i > needs_memory.upper
         loop
            need := needs_memory.item(i)
            if need.in_cycle then
               if need.cluster.depth < depth then
                  need.cluster.set_depth(depth)
                  Result := True
               end
            elseif need.cluster.depth <= depth then
               need.cluster.set_depth(depth + 1)
               Result := True
            end
            i := i + 1
         end
      end

   fix_needs_depth: BOOLEAN is
      local
         i: INTEGER
      do
         from
            i := needs_memory.lower
         until
            i > needs_memory.upper
         loop
            if needs_memory.item(i).cluster.fix_depth(mark) then
               Result := True
            end
            i := i + 1
         end
      end

feature {LIBERTY_ETC_CLUSTER}
   set_depth (a_depth: like depth) is
      require
         a_depth > depth
      do
         if log.is_trace then
            log.trace.put_string(name)
            log.trace.put_string(once " (mark=")
            log.trace.put_integer(mark)
            log.trace.put_string(once "): depth from ")
            log.trace.put_integer(depth)
            log.trace.put_string(once " to ")
            log.trace.put_integer(a_depth)
            log.trace.put_new_line
         end
         depth := a_depth
      ensure
         depth = a_depth
      end

feature {LIBERTY_CLUSTER}
   set_cluster (a_cluster: like cluster) is
      require
         cluster = Void
         a_cluster /= Void
      do
         cluster := a_cluster
      ensure
         cluster = a_cluster
      end

feature {}
   make (a_name: like name; a_locations: like locations) is
      require
         not a_name.is_empty
         not a_locations.is_empty
      do
         name := a_name
         locations := a_locations
         create needs_memory.with_capacity(2)
         if log.is_trace then
            log.trace.put_string(once "Master cluster definition: ")
            log.trace.put_string(name)
            log.trace.put_string(once " -> ")
            log.trace.put_line(a_locations.out)
         end
      ensure
         name = a_name
         locations = a_locations
      end

   needs_memory: FAST_ARRAY[LIBERTY_ETC_NEEDS]

invariant
   name /= Void
   not locations.is_empty
   needs_memory /= Void

end -- class LIBERTY_ETC_CLUSTER