# This has been ripped in part from CouchRest: http://github.com/mattetti/couchrest/tree/master
# License information is in LICENSE_COUCHREST, modifications are covered under the aqua license

module Aqua
  module Store 
    module CouchDB
      class Server
        attr_accessor :uri, :uuid_batch_count, :uuids
        attr_reader :namespace
    
        def initialize(opts={})
          opts = Mash.new(opts) unless opts.empty?
          self.uri =              opts[:server] || 'http://127.0.0.1:5984'
          self.uuid_batch_count = opts[:uuid_batch_count] || 1000 
          self.namespace =        opts[:namespace].to_s 
        end 
    
        def namespace=( name )
          default = 'aqua'
          name ||= default
          name = CouchDB.escape( name )
          name = default if name.empty? 
          @namespace = name
        end
    
        # DATABASE MANAGMENT -----------------
    
        # Lists all database names on the server
        def database_names
          dbs = CouchDB.get( "#{@uri}/_all_dbs" )
          dbs.select{|name| name.match(/\A#{namespace}_?/)}
        end
    
        def databases
          dbs = [] 
          database_names.each do |db_name|
            dbs << Database.new( db_name.gsub(/\A#{namespace}_|\A#{namespace}\z/, '') , :server => self )
          end
          dbs  
        end  
    
        # Deletes all databases named for this namespace (i.e. this server)
        # Use with caution ... it is a permanent and undoable change
        def delete_all! 
          databases.each{ |db| db.delete! }
        end 
        
        # Deletes all database with the less exection raising method: database.delete. This will
        # only raise errors related to request problems, and not errors related to the database not
        # being found for deletion. 
        def delete_all 
          databases.each{ |db| db.delete }
        end 
        
        # Returns a CouchRest::Database for the given name
        def database(name)
          db = Database.new( name, :server => self )
          db.exists? ? db : nil
        end

        # Creates the database if it doesn't exist
        def database!(name)
          Database.create( name, :server => self )  
        end

        # GET the welcome message
        def info
          CouchDB.get "#{uri}/"
        end
    
        # Restart the CouchDB instance
        def restart!
          CouchDB.post "#{uri}/_restart"
        end
    
        # counts the number of uuids available, used by Database to limit bulk save
        def uuid_count
          if uuids 
            uuids.size 
          else
            load_uuids  
            uuid_batch_count
          end  
        end  

        # Retrive an unused UUID from CouchDB. Server instances manage caching a list of unused UUIDs.
        def next_uuid(count = @uuid_batch_count)
          @uuids ||= []
          if uuids.empty?
            load_uuids(count)
          end
          uuids.pop
        end
    
        def load_uuids( count=@uuid_batch_count ) 
          @uuids = CouchDB.get("#{@uri}/_uuids?count=#{count}")["uuids"]
        end  
    
    
      end # Server 
    end # CouchDB 
  end # Store  
end # Aqua