/*=======================================================
 * ForCommand.java 
 *
 * "A Tcl like language implementation in Java named APWTCL
 * ((Java) Arnulf's Preferred Web Tcl)"
 *
 * APWTCL ForCommand class
 *
 * Released under same BSD license as Tcl.
 * (Tcl BSD license found at <http://www.tcl.tk/software/tcltk/license.html>)
 *
 * Copyright 2012 Arnulf P. Wiedemann
 *
 */

package org.apwtcl.lang.cmd;

import java.util.ArrayList;

import org.apwtcl.lang.CallFrame;
import org.apwtcl.lang.Command;
import org.apwtcl.lang.Interp;
import org.apwtcl.lang.ApwtclObj;
import org.apwtcl.lang.Token;

public class ForCommand extends Token {

  /* ==================== ForCommand ================================== */
  public ForCommand() {
  }

  /* ==================== forCmd ================================== */
  public int forCmd(Interp interp, ArrayList<ApwtclObj> args) {
//print("for called!"+args+"!");
    int retval;
    int bool = 1;
    ArrayList<Integer> bool_ptr = new ArrayList<Integer>();
    ApwtclObj var_name_ptr = null;
    ApwtclObj stop_var_name_ptr = null;
    boolean evalstart = false;
    boolean evalnext = false;
    boolean out = false;
    boolean testcond = false;

    if (args.size() != 5) {
      interp.wrongNumArgs(1, args, "start test next body");
      return ERROR;
    }
    /* Do the initialisation */
    if ((retval = interp.eval_statement.evalObj(args.get(1))) != OK) {
      return retval;
    }
    /* And do the first test now. Better for optimisation
     * if we can do next/test at the bottom of the loop
     */
    retval = interp.eval_expression.getBoolFromExpr(args.get(2), bool_ptr);
    bool = bool_ptr.get(0);
    /* Ready to do the body as follows:
     * while (1) {
     *     body // check retcode
     *     next // check retcode
     *     test // check retcode/test bool
     * }
     */

/*
if (false) {
    /* Check if the for is on the form:
     *      for ... {$i < CONST} {incr i}
     *      for ... {$i < $j} {incr i}
     */
/*
    if (retval == interp.OK && bool_ptr) {
      var incr_script;
      var expr;
      var stop = new Array();
      var current_val = new Array();
      var proc_epoch;
      var obj_ptr;
      var cmp_offset;


      /* Do it only if there aren't shared arguments */
/*
      expr = interp.eval_expression.getExpression(args[2]);
      incr_script = interp.script_obj_type.getScript(args[3]);
      /* Ensure proper lengths to start */
/*
      if (incr_script.len != 3 || !expr || expr.len != 3) {
        evalstart = true;
      }
      /* Ensure proper token types. */
/*
      if (!evalstart) {
        if (incr_script.script_object.tokens[1].token != interp.TOKEN_ESC ||
          expr.token_list[0].token != interp.TOKEN_VAR ||
          (expr.token_list[1].token != interp.TOKEN_EXPR_INT && expr.token_list[1].token != interp.TOKEN_VAR)) {
          evalstart = true;
        }
      }
      if (!evalstart) {
        if (expr.token_list[2].token == interp.TOKEN_EXPROP_LT) {
          cmp_offset = 0;
        } else {
          if (expr.token_list[2].token == interp.TOKEN_EXPROP_LTE) {
            cmp_offset = 1;
          } else {
            evalstart = true;
          }
        }
      }
      if (!evalstart) {
        /* Update command must be incr */
/*
        if (!incr_script.script_object.tokens[1].obj_ptr.getString() == "incr") {
          evalstart = true;
        }
      }
        /* incr, expression must be about the same variable */
/*
      if (!evalstart) {
        if (!interp.string_obj_type.stringEqObj(incr_script.script_object.tokens[2].obj_ptr, expr.token_list[0].obj_ptr)) {
          evalstart = true;
        }
      }
        /* Get the stop condition (must be a variable or integer) */
/*
      if (!evalstart) {
        if (expr.token_list[1].tken == interp.TOKEN_EXPR_INT) {
          if (interp.default_obj.getWide(expr.token_list[1].obj_ptr, stop) == interp.ERROR) {
            evalstart = true;
          }
	  stop = stop[0];
        } else {
            stop_var_name_ptr = expr.token_list[1].obj_ptr;
            stop_var_name_ptr.incrRefCount("I_PKG_CORECMD_2");
            /* Keep the compiler happy */
/*
            stop = 0;
        }
      }
      if (!evalstart) {
        /* Initialization */
/*
        proc_epoch = interp.proc_epoch;
        var_name_ptr = expr.token_list[0].obj_ptr;
        var_name_ptr.incrRefCount("I_PKG_CORECMD_3");

        obj_ptr = interp.variable_obj_type.getVariable(var_name_ptr, interp.FUNCTION_FLAGS_NONE);
	current_val = new Array();
        if (obj_ptr == null || interp.default_obj.getWide(obj_ptr, current_val) != interp.OK) {
          testcond = true;
        }
	current_val = current_val[0];
      }
      if (!testcond) {
        /* --- OPTIMIZED FOR --- */
/*
        while (retval == interp.OK) {
          /* === Check condition === */
          /* Note that currentVal is already set here */
          /* Immediate or Variable? get the 'stop' value if the latter. */
/*
          if (stop_var_name_ptr) {
            obj_ptr = interp.variable_obj_type.getVariable(stop_var_name_ptr, interp.FUNCTION_FLAGS_NONE);
            if (obj_ptr == null || interp.default_obj.getWide(obj_ptr, stop) != interp.OK) {
              testcond = true;
	      break;
            }
          }
          if (current_val >= stop + cmp_offset) {
            break;
          }
          /* Eval body */
/*
          retval = interp.eval_statement.evalObj(args[4]);
          if (retval == interp.OK || retval == interp.CONTINUE) {
            retval = interp.OK;
            /* If there was a change in procedures/command continue
             * with the usual [for] command implementation */
/*
            if (proc_epoch != interp.proc_epoch) {
              evalnext = true;
            }
	    if (!evalnext) {
              obj_ptr = interp.variable_obj_type.getVariable(var_name_ptr, interp.FUNCTION_FLAGS_LEAVE_ERRMSG);
              /* Increment */
/*
              if (obj_ptr == null) {
                retval = interp.ERROR;
                out = true;
		break;
              }
              if (!obj_ptr.isShared() && obj_ptr.obj_type == interp.int_obj_type) {
                currentVal = ++interp.default_obj.wideValue(obj_ptr);
                obj_ptr.invalidateStringRep();
              } else {
                current_value = new Array();
                if (interp.default_obj.getWide(obj_ptr, current_val) != interp.OK ||
                    interp.variable_obj_type.setVariable(var_name_ptr, interp.int_obj_type.newIntObj(++current_val[0])) != interp.OK) {
                  evalnext = true;
                }
              }
            }
          }
        }
        out = true;
      }
    }
}
*/
evalstart = true;
evalnext = true;
testcond = true;
    if (evalstart) {
      while (bool != 0 && (retval == OK || retval == CONTINUE)) {
        /* Body */
        retval = interp.eval_statement.evalObj(args.get(4));
        if (retval == OK || retval == CONTINUE) {
          /* increment */
          if (evalnext) {
            retval = interp.eval_statement.evalObj(args.get(3));
            if (retval == OK || retval == CONTINUE) {
                /* test */
              if (testcond) {
                bool_ptr = new ArrayList<Integer>();
                retval = interp.eval_expression.getBoolFromExpr(args.get(2), bool_ptr);
                bool = bool_ptr.get(0);
              }
            }
          }
        }
      }
    }
    if (out) {
      if (stop_var_name_ptr != null) {
        stop_var_name_ptr.decrRefCount("D_PKG_CORE_CMD_3");
      }
    }
    if (var_name_ptr != null) {
      var_name_ptr.decrRefCount("D_PKG_CORE_CMD_4");
    }
    if (retval == CONTINUE || retval == BREAK || retval == OK) {
      interp.setEmptyResult();
      return OK;
    }
    return retval;
  }

}