////////////////////////////////////////////////
////s~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~s////
////s           www.testbench.in           s////
////s                                      s////
////s        SystemVerilog Tutorial        s////
////s           gopi@testbench.in          s////
////s~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~s////
////////////////////////////////////////////////
`ifndef GUARD_ENV
`define GUARD_ENV

class Environment ;

  virtual mem_interface.MEM    mem_intf       ;
  virtual input_interface.IP  input_intf     ;
  virtual output_interface.OP output_intf[4] ;

function new(virtual mem_interface.MEM    mem_intf_new       ,
             virtual input_interface.IP  input_intf_new     ,
             virtual output_interface.OP output_intf_new[4] );

  this.mem_intf      = mem_intf_new    ;
  this.input_intf    = input_intf_new  ;
  this.output_intf   = output_intf_new ;

  $display(" 0 : Environemnt : created env object",$time);
endfunction : new

function void build();
  $display(" 0 : Environemnt : start of build() method",$time);
  $display(" 0 : Environemnt : end of build() method",$time);
endfunction : build

task reset();
  $display(" 0 : Environemnt : start of reset() method",$time);
  // Drive all DUT inputs to a known state
  mem_intf.cb.mem_data      <= 0;
  mem_intf.cb.mem_add       <= 0;
  mem_intf.cb.mem_en        <= 0;
  mem_intf.cb.mem_rd_wr     <= 0;
  input_intf.cb.data_in     <= 0;
  input_intf.cb.data_status <= 0;
  output_intf[0].cb.read    <= 0;
  output_intf[1].cb.read    <= 0;
  output_intf[2].cb.read    <= 0;
  output_intf[3].cb.read    <= 0;

  // Reset the DUT
  input_intf.reset       <= 1;
  repeat (4) @ input_intf.clock;
  input_intf.reset       <= 0;

  $display(" 0 : Environemnt : end of reset() method",$time);
endtask : reset

task cfg_dut();
  $display(" 0 : Environemnt : start of cfg_dut() method",$time);

  mem_intf.cb.mem_en <= 1;
  @(posedge mem_intf.clock);
  mem_intf.cb.mem_rd_wr <= 1;

  @(posedge mem_intf.clock);
  mem_intf.cb.mem_add  <= 8'h0;
  mem_intf.cb.mem_data <= `P0;
  $display(" 0 : Environemnt : Port 0 Address %h ",$time,`P0);

  @(posedge mem_intf.clock);
  mem_intf.cb.mem_add  <= 8'h1;
  mem_intf.cb.mem_data <= `P1;
  $display(" 0 : Environemnt : Port 1 Address %h ",$time,`P1);

  @(posedge mem_intf.clock);
  mem_intf.cb.mem_add  <= 8'h2;
  mem_intf.cb.mem_data <= `P2;
  $display(" 0 : Environemnt : Port 2 Address %h ",$time,`P2);

  @(posedge mem_intf.clock);
  mem_intf.cb.mem_add  <= 8'h3;
  mem_intf.cb.mem_data <= `P3;
  $display(" 0 : Environemnt : Port 3 Address %h ",$time,`P3);

  @(posedge mem_intf.clock);
  mem_intf.cb.mem_en    <=0;
  mem_intf.cb.mem_rd_wr <= 0;
  mem_intf.cb.mem_add   <= 0;
  mem_intf.cb.mem_data  <= 0;


  $display(" 0 : Environemnt : end of cfg_dut() method",$time);
endtask : cfg_dut

task start();
  $display(" 0 : Environemnt : start of start() method",$time);
  $display(" 0 : Environemnt : end of start() method",$time);
endtask : start

task wait_for_end();
  $display(" 0 : Environemnt : start of wait_for_end() method",$time);
  repeat(10000) @(input_intf.clock);
  $display(" 0 : Environemnt : end of wait_for_end() method",$time);
endtask : wait_for_end

task run();
  $display(" 0 : Environemnt : start of run() method",$time);
  build();
  reset();
  cfg_dut();
  start();
  wait_for_end();
  report();
  $display(" 0 : Environemnt : end of run() method",$time);
endtask : run

task report();
endtask : report

endclass

`endif