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    Types: TextFile
    Names: »B«

└─⟦bfaa708f6⟧ Bits:30000531 8mm tape, Rational 1000, INSIGHT 1_3_0
    └─ ⟦c51948655⟧ »DATA« 
        └─⟦266b31e86⟧ 
            └─⟦this⟧ 

TextFile

with Panel_Interface;
with Client;
with Message_Types;
with Message_Dispatch;
with Message;
with Network;
with Log_Writer;
with Seats;
package body Light_Controller is

    Light_Controller_Id : Client.Id;
    -- Client Id for this module.  There is a dispatcher task handling
    -- requests addressed to this client.

    procedure Start is
    begin
        null; -- Startup automatic during elaboration.
    end Start;


    procedure Shutdown is
    begin
        null; -- no explicit shutdown needed.
    end Shutdown;



    task Dispatcher is
        entry Start;
        -- The client must be registered in elaboration code before this
        -- entry is called.  Once called, begin dispatching requests.
    end Dispatcher;

    task body Dispatcher is
        Packet : Message.Packet;
        -- This packet is allocated by the Message_Dispatch package and must
        -- be explicitly freed here.

        function Get_Seat (Cmd : String) return Seats.Seat_Id is
        begin
            if Cmd'Length >= 2 then
                return Seats.Seat_Id'Value (Cmd (Cmd'First + 1 .. Cmd'Last));
            else
                return 0;
            end if;
        exception
            when others =>
                return 0;
        end Get_Seat;

    begin  
        accept Start;
        loop
            begin
                -- Get a message
                Message_Dispatch.Get_Message (Light_Controller_Id, Packet);

                -- Decode message and process.
                declare
                    Cmd : constant String := Message.Packet_Body (Packet);
                    Seat : Seats.Seat_Id := Get_Seat (Cmd);
                begin
                    -- 1st char T => on F => off, rest of string is seat
                    -- number.
                    case Cmd (Cmd'First) is
                        when 'T' =>
                            Log_Writer.Log_Message
                               ("Light_Controller",
                                "Light ON: " & Seats.Seat_Id'Image (Seat));
                            -- Call physical controller to turn light on
                            Panel_Interface.Light_On (Seat);

                        when 'F' =>
                            Log_Writer.Log_Message
                               ("Light_Controller",
                                "Light OFF:" & Seats.Seat_Id'Image (Seat));
                            -- Call physical controller to turn light off
                            Panel_Interface.Light_Off (Seat);
                        when others =>
                            Log_Writer.Log_Message
                               ("Light_Controller.Dispatcher",
                                "illegal message");
                    end case;
                    Message_Dispatch.Free_Buffer (Packet);
                exception
                    when others =>
                        Log_Writer.Log_Message
                           ("Light_Controller.Dispatcher", "exception");
                        delay 3.0;  -- avoid infinite busy loops
                end;
            end;
        end loop;
    end Dispatcher;

begin
    -- initialization: Register client and start dispatcher task
    Light_Controller_Id := Client.Register ("Light_Controller");
    Dispatcher.Start;
end Light_Controller;