module Rfm
  # The Layout object represents a single FileMaker Pro layout. You use it to interact with 
  # records in FileMaker. *All* access to FileMaker data is done through a layout, and this
  # layout determines which _table_ you actually hit (since every layout is explicitly associated
  # with a particular table -- see FileMakers Layout->Layout Setup dialog box). You never specify
  # _table_ information directly in RFM.
  #
  # Also, the layout determines which _fields_ will be returned. If a layout contains only three
  # fields from a large table, only those three fields are returned. If a layout includes related
  # fields from another table, they are returned as well. And if the layout includes portals, all
  # data in the portals is returned (see Record::portal for details).
  #
  # As such, you can _significantly_ improve performance by limiting what you put on the layout.
  #
  # =Using Layouts
  #
  # The Layout object is where you get most of your work done. It includes methods for all
  # FileMaker actions:
  # 
  # * Layout::all
  # * Layout::any
  # * Layout::find
  # * Layout::edit
  # * Layout::create
  # * Layout::delete
  #
  # =Running Scripts
  # 
  # In FileMaker, execution of a script must accompany another action. For example, to run a script
  # called _Remove Duplicates_ with a found set that includes everybody
  # named _Bill_, do this:
  #
  #   myLayout.find({"First Name" => "Bill"}, :post_script => "Remove Duplicates")
  #
  # ==Controlling When the Script Runs
  #
  # When you perform an action in FileMaker, it always executes in this order:
  # 
  # 1. Perform any find
  # 2. Sort the records
  # 3. Return the results
  #
  # You can control when in the process the script runs. Each of these options is available:
  #
  # * *post_script* tells FileMaker to run the script after finding and sorting
  # * *pre_find_script* tells FileMaker to run the script _before_ finding
  # * *pre_sort_script* tells FileMaker to run the script _before_ sorting, but _after_ finding
  #
  # ==Passing Parameters to a Script
  # 
  # If you want to pass a parameter to the script, use the options above, but supply an array value
  # instead of a single string. For example:
  #
  #   myLayout.find({"First Name" => "Bill"}, :post_script => ["Remove Duplicates", 10])
  #
  # This sample runs the script called "Remove Duplicates" and passes it the value +10+ as its 
  # script parameter.
  #
  # =Common Options
  # 
  # Most of the methods on the Layout object accept an optional hash of +options+ to manipulate the
  # action. For example, when you perform a find, you will typiclaly get back _all_ matching records. 
  # If you want to limit the number of records returned, you can do this:
  #
  #   myLayout.find({"First Name" => "Bill"}, :max_records => 100)
  # 
  # The +:max_records+ option tells FileMaker to limit the number of records returned.
  #
  # This is the complete list of available options:
  # 
  # * *max_records* tells FileMaker how many records to return
  #
  # * *skip_records* tells FileMaker how many records in the found set to skip, before
  #   returning results; this is typically combined with +max_records+ to "page" through 
  #   records
  #
  # * *sort_field* tells FileMaker to sort the records by the specified field
  # 
  # * *sort_order* can be +descend+ or +ascend+ and determines the order
  #   of the sort when +sort_field+ is specified
  #
  # * *post_script* tells FileMaker to perform a script after carrying out the action; you 
  #   can pass the script name, or a two-element array, with the script name first, then the
  #   script parameter
  #
  # * *pre_find_script* is like +post_script+ except the script runs before any find is 
  #   performed
  #
  # * *pre_sort_script* is like +pre_find_script+ except the script runs after any find
  #   and before any sort
  # 
  # * *response_layout* tells FileMaker to switch layouts before producing the response; this
  #   is useful when you need a field on a layout to perform a find, edit, or create, but you
  #   want to improve performance by not including the field in the result
  #
  # * *logical_operator* can be +and+ or +or+ and tells FileMaker how to process multiple fields
  #   in a find request
  # 
  # * *modification_id* lets you pass in the modification id from a Record object with the request;
  #   when you do, the action will fail if the record was modified in FileMaker after it was retrieved
  #   by RFM but before the action was run
  #
  #
  # =Attributes
  #
  # The Layout object has a few useful attributes:
  #
  # * +name+ is the name of the layout
  #
  # * +field_controls+ is a hash of FieldControl objects, with the field names as keys. FieldControl's
  #   tell you about the field on the layout: how is it formatted and what value list is assigned
  #
  # Note: It is possible to put the same field on a layout more than once. When this is the case, the
  # value in +field_controls+ for that field is an array with one element representing each instance
  # of the field.
  # 
  # * +value_lists+ is a hash of arrays. The keys are value list names, and the values in the hash
  #   are arrays containing the actual value list items. +value_lists+ will include every value
  #   list that is attached to any field on the layout
  
  class Layout
		
  	include ComplexQuery
    
    # Initialize a layout object. You never really need to do this. Instead, just do this:
    # 
    #   myServer = Rfm::Server.new(...)
    #   myDatabase = myServer["Customers"]
    #   myLayout = myDatabase["Details"]
    #
    # This sample code gets a layout object representing the Details layout in the Customers database
    # on the FileMaker server.
    # 
    # In case it isn't obvious, this is more easily expressed this way:
    #
    #   myServer = Rfm::Server.new(...)
    #   myLayout = myServer["Customers"]["Details"]
    def initialize(name, db_obj)
    	raise Rfm::Error::RfmError.new(0, "New instance of Rfm::Layout has no name.") if name.to_s == ''
      @name = name.to_s
      rfm_metaclass.instance_variable_set :@db, db_obj
      
      @loaded = false
      @field_controls = Rfm::CaseInsensitiveHash.new
      @value_lists = Rfm::CaseInsensitiveHash.new
			#       @portal_meta = nil
			#       @field_names = nil
    end
    
    meta_attr_reader :db
    attr_reader :name #, :db
    attr_writer :field_names, :portal_meta, :table
    def_delegator :db, :server
    alias_method :database, :db
    
    
    # These methods are to be inclulded in Layout and SubLayout, so that
    # they have their own descrete 'self' in the master class and the subclass.
    module LayoutModule
    
	    # Returns a ResultSet object containing _every record_ in the table associated with this layout.
	    def all(options = {})
	      get_records('-findall', {}, options)
	    end
	    
	    # Returns a ResultSet containing a single random record from the table associated with this layout.
	    def any(options = {})
	      get_records('-findany', {}, options)
	    end
	  
	    # Finds a record. Typically you will pass in a hash of field names and values. For example:
	    #
	    #   myLayout.find({"First Name" => "Bill"})
	    #
	    # Values in the hash work just like value in FileMaker's Find mode. You can use any special
	    # symbols (+==+, +...+, +>+, etc...).
	    #
	    # If you pass anything other than a hash as the first parameter, it is converted to a string and
	    # assumed to be FileMaker's internal id for a record (the recid).
	    def find(hash_or_recid, options = {})
	      if hash_or_recid.kind_of? Hash
	        get_records('-find', hash_or_recid, options)
	      else
	        get_records('-find', {'-recid' => hash_or_recid.to_s}, options)
	      end
	    end
	  
	    # Updates the contents of the record whose internal +recid+ is specified. Send in a hash of new
	    # data in the +values+ parameter. Returns a RecordSet containing the modified record. For example:
	    #
	    #   recid = myLayout.find({"First Name" => "Bill"})[0].record_id
	    #   myLayout.edit(recid, {"First Name" => "Steve"})
	    #
	    # The above code would find the first record with _Bill_ in the First Name field and change the 
	    # first name to _Steve_.
	    def edit(recid, values, options = {})
	      get_records('-edit', {'-recid' => recid}.merge(values), options)
	    end
	    
	    # Creates a new record in the table associated with this layout. Pass field data as a hash in the 
	    # +values+ parameter. Returns the newly created record in a RecordSet. You can use the returned
	    # record to, ie, discover the values in auto-enter fields (like serial numbers). 
	    #
	    # For example:
	    #
	    #   result = myLayout.create({"First Name" => "Jerry", "Last Name" => "Robin"})
	    #   id = result[0]["ID"]
	    #
	    # The above code adds a new record with first name _Jerry_ and last name _Robin_. It then
	    # puts the value from the ID field (a serial number) into a ruby variable called +id+.
	    def create(values, options = {})
	      get_records('-new', values, options)
	    end
	    
	    # Deletes the record with the specified internal recid. Returns a ResultSet with the deleted record.
	    #
	    # For example:
	    #
	    #   recid = myLayout.find({"First Name" => "Bill"})[0].record_id
	    #   myLayout.delete(recid)
	    # 
	    # The above code finds every record with _Bill_ in the First Name field, then deletes the first one.
	    def delete(recid, options = {})
	      get_records('-delete', {'-recid' => recid}, options)
	      return nil
	    end
	    
	    def get_records(action, extra_params = {}, options = {})
	      include_portals = options[:include_portals] ? options.delete(:include_portals) : nil
	      xml_response = db.server.connect(db.account_name, db.password, action, params.merge(extra_params), options).body
	      Rfm::Resultset.new(db.server, xml_response, self, include_portals)
	    end
	    
	    def params
	      {"-db" => db.name, "-lay" => self.name}
	    end
	    
	  end # LayoutModule
	  include LayoutModule
    
    
    def field_controls
      load unless @loaded
      @field_controls
    end
    
  	def field_names
  		load unless @field_names
  		@field_names
  	end
  	
  	def field_names_no_load
  		@field_names
  	end
    
    def value_lists
      load unless @loaded
      @value_lists
    end
    
  	def total_count
  		any.total_count
  	end
  	
  	def portal_meta
  		@portal_meta ||= any.portal_meta
  	end
  	
  	def portal_meta_no_load
  		@portal_meta
  	end
  	
  	def portal_names
  		portal_meta.keys
  	end
  	
  	def table
  		@table ||= any.table
  	end
  	
  	def table_no_load
  		@table
  	end
    
    def load
      @loaded = true
      fmpxmllayout = db.server.load_layout(self)
      doc = XmlParser.new(fmpxmllayout.body, :namespace=>false, :parser=>server.state[:parser])
      
      # check for errors
      error = doc['FMPXMLLAYOUT']['ERRORCODE'].to_s.to_i
      raise Rfm::Error::FileMakerError.getError(error) if error != 0
      
      # process valuelists
      vlists = doc['FMPXMLLAYOUT']['VALUELISTS']['VALUELIST']
      if !vlists.nil?    #root.elements['VALUELISTS'].size > 0
        vlists.each {|valuelist|
          name = valuelist['NAME']
          @value_lists[name] = valuelist['VALUE'].collect{|value|
          	Rfm::Metadata::ValueListItem.new(value['__content__'], value['DISPLAY'], name)
          } rescue []
        }
        @value_lists.freeze
      end

      # process field controls
      doc['FMPXMLLAYOUT']['LAYOUT']['FIELD'].each {|field|
        name = field['NAME']
        style = field['STYLE']
        type = style['TYPE']
        value_list_name = style['VALUELIST']
        value_list = @value_lists[value_list_name] if value_list_name != ''
        field_control = Rfm::Metadata::FieldControl.new(name, type, value_list_name, value_list)
        existing = @field_controls[name]
        if existing
          if existing.kind_of?(Array)
            existing << field_control
          else
            @field_controls[name] = Array[existing, field_control]
          end
        else
          @field_controls[name] = field_control
        end
      }
      @field_names ||= @field_controls.collect{|k,v| v.name rescue v[0].name}
      @field_controls.freeze
    end
    
  	private :load, :get_records, :params
      
      
  end # Layout
end # Rfm