/*
 * Copyright (c) 1999-2010 Picture Elements, Inc.
 *    Stephen Williams (steve@picturel.com)
 * Copyright (c) 2001 Stephan Boettcher <stephan@nevis.columbia.edu>
 *
 *    This source code is free software; you can redistribute it
 *    and/or modify it in source code form under the terms of the GNU
 *    General Public License as published by the Free Software
 *    Foundation; either version 2 of the License, or (at your option)
 *    any later version. In order to redistribute the software in
 *    binary form, you will need a Picture Elements Binary Software
 *    License.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
 *  ---
 *    You should also have received a copy of the Picture Elements
 *    Binary Software License offer along with the source. This offer
 *    allows you to obtain the right to redistribute the software in
 *    binary (compiled) form. If you have not received it, contact
 *    Picture Elements, Inc., 777 Panoramic Way, Berkeley, CA 94704.
 */

# include  "vpi_priv.h"
# include  "memory.h"
# include  "statistics.h"
# include  <stdlib.h>
# include  <string.h>
# include  <assert.h>

# include  <stdio.h>

extern const char hex_digits[256];

static void memory_make_word_handles(struct __vpiMemory*rfp);

struct __vpiMemoryWord {
      struct __vpiHandle base;
      struct __vpiMemory*mem;
      struct __vpiDecConst index;
};

struct __vpiMemory {
      struct __vpiHandle base;
      struct __vpiScope* scope;
      struct __vpiMemoryWord*words;
      vvp_memory_t mem;
      struct __vpiDecConst left_range;
      struct __vpiDecConst right_range;
      struct __vpiDecConst word_left_range;
      struct __vpiDecConst word_right_range;

};

struct __vpiMemWordIterator {
      struct __vpiHandle base;
      struct __vpiMemory*mem;
      unsigned next;
};

static vpiHandle memory_get_handle(int code, vpiHandle obj)
{
      struct __vpiMemory*rfp = (struct __vpiMemory*)obj;

      assert(obj->vpi_type->type_code==vpiMemory);

      switch(code){
	  case vpiLeftRange:
	    return &(rfp->left_range.base);

	  case vpiRightRange:
	    return &(rfp->right_range.base);

	  case vpiScope:
	    return &rfp->scope->base;

      }

      return 0;
}

static int vpi_memory_get(int code, vpiHandle ref)
{
      struct __vpiMemory*rfp = (struct __vpiMemory*)ref;

      assert(ref->vpi_type->type_code==vpiMemory);

      switch (code) {
	  case vpiSize:
	    return (int)memory_size(rfp->mem);

	  default:
	    return 0;
      }
}

static char* memory_get_str(int code, vpiHandle ref)
{
      assert(ref->vpi_type->type_code==vpiMemory);

      struct __vpiMemory*rfp = (struct __vpiMemory*)ref;

      char *bn = strdup(vpi_get_str(vpiFullName, &rfp->scope->base));
      char *nm = memory_name(rfp->mem);

      char *rbuf = need_result_buf(strlen(bn) + strlen(nm) + 2, RBUF_STR);

      switch (code) {
	  case vpiFullName:
	    sprintf(rbuf, "%s.%s", bn, nm);
	    free(bn);
	    return rbuf;
	  case vpiName:
	    strcpy(rbuf, nm);
	    free(bn);
	    return rbuf;
      }

      free(bn);
      return 0;
}

static vpiHandle memory_scan(vpiHandle ref, int)
{
      struct __vpiMemWordIterator*obj = (struct __vpiMemWordIterator*)ref;
      assert(ref->vpi_type->type_code == vpiIterator);

      if (obj->next >= memory_size(obj->mem->mem)) {
	    vpi_free_object(ref);
	    return 0;
      }

      return &obj->mem->words[obj->next++].base;
}

static int mem_iter_free_object(vpiHandle ref)
{
      free(ref);
      return 1;
}

static const struct __vpirt vpip_mem_iter_rt = {
      vpiIterator,
      0,
      0,
      0,
      0,
      0,
      0,
      memory_scan,
      &mem_iter_free_object
};


static vpiHandle memory_iterate(int code, vpiHandle ref)
{
      struct __vpiMemory*rfp = (struct __vpiMemory*)ref;
      assert(ref->vpi_type->type_code==vpiMemory);

      switch (code) {
	  case vpiMemoryWord: {
		memory_make_word_handles(rfp);

		struct __vpiMemWordIterator*res =
		      (struct __vpiMemWordIterator*)
		      calloc(1, sizeof(struct __vpiMemWordIterator));
		assert(res);
		res->base.vpi_type = &vpip_mem_iter_rt;
		res->mem  = rfp;
		res->next = 0;
		return &(res->base);
	  }
      }

      return 0;
}

static vpiHandle memory_index(vpiHandle ref, int index)
{
      struct __vpiMemory*rfp = (struct __vpiMemory*)ref;
      assert(ref->vpi_type->type_code==vpiMemory);

      index -= memory_root(rfp->mem);
      if (index >= (int)memory_size(rfp->mem)) return 0;
      if (index < 0) return 0;

      memory_make_word_handles(rfp);
      return &(rfp->words[index].base);
}

//==============================

static vpiHandle memory_word_get_handle(int code, vpiHandle obj)
{
      struct __vpiMemoryWord*rfp = (struct __vpiMemoryWord*)obj;
      assert(obj->vpi_type->type_code==vpiMemoryWord);

      switch(code){
	  case vpiLeftRange:
	    return &(rfp->mem->word_left_range.base);

	  case vpiRightRange:
	    return &(rfp->mem->word_right_range.base);

	  case vpiIndex:
	    return &(rfp->index.base);
      }


      return 0;
}

static int memory_word_get(int code, vpiHandle ref)
{
      struct __vpiMemoryWord*rfp = (struct __vpiMemoryWord*)ref;
      assert(ref->vpi_type->type_code==vpiMemoryWord);

      switch (code) {
	  case vpiSize:
	    return memory_data_width(rfp->mem->mem);

	  default:
	    return 0;
      }
}

static vpiHandle memory_word_put(vpiHandle ref, p_vpi_value val)
{
      struct __vpiMemoryWord*rfp = (struct __vpiMemoryWord*)ref;
      assert(ref->vpi_type->type_code==vpiMemoryWord);


	/* Get the width of the memory, and the byte index of the
	   first byte of the word. */
      unsigned width = memory_data_width(rfp->mem->mem);
      unsigned word_offset = memory_root(rfp->mem->mem);
      unsigned bidx = (rfp->index.value - word_offset) * ((width+3)&~3);

      switch (val->format) {

	  case vpiVectorVal:
	    for (unsigned widx = 0;  widx < width;  widx += 32) {
		  p_vpi_vecval cur = val->value.vector + (widx/32);
		  for (unsigned idx = widx
			     ; idx < width && idx < widx+32
			     ; idx += 1) {
			int aval = (cur->aval >> (idx%32)) & 1;
			int bval = (cur->bval >> (idx%32)) & 1;
			unsigned char val = (bval<<1) | (aval^bval);
			memory_set(rfp->mem->mem, bidx+idx, val);
		  }
	    }
	    break;

	  case vpiIntVal:
	    for (unsigned widx = 0;  widx < width;  widx += 32) {
		  int cur = val->value.integer;
		  for (unsigned idx = widx
			     ; idx < width && idx < widx+32
			     ; idx += 1) {
			unsigned char val = (cur&1)? 1 : 0;
			memory_set(rfp->mem->mem, bidx+idx, val);
			cur >>= 1;
		  }
	    }
	    break;

	      /* If the caller tries to set a HexStrVal, convert it to
		 bits and write the bits into the word. */
	  case vpiHexStrVal: {
		unsigned char*bits = new unsigned char[(width+3) / 4];
		vpip_hex_str_to_bits(bits, width, val->value.str, false);

		for (unsigned idx = 0 ;  idx < width ;  idx += 1) {
		      unsigned bb = idx / 4;
		      unsigned bs = (idx % 4) * 2;
		      unsigned val = (bits[bb] >> bs) & 0x03;
		      memory_set(rfp->mem->mem, bidx+idx, val);
		}

		delete[]bits;
		break;
	  }

	  case vpiDecStrVal: {
		unsigned char*bits = new unsigned char[width];
		vpip_dec_str_to_bits(bits, width, val->value.str, false);

		for (unsigned idx = 0 ;  idx < width ;  idx += 1) {
		      memory_set(rfp->mem->mem, bidx+idx, bits[idx]);
		}

		delete[]bits;
		break;
	  }

	  case vpiOctStrVal: {
		unsigned char*bits = new unsigned char[(width+3) / 4];
		vpip_oct_str_to_bits(bits, width, val->value.str, false);

		for (unsigned idx = 0 ;  idx < width ;  idx += 1) {
		      unsigned bb = idx / 4;
		      unsigned bs = (idx % 4) * 2;
		      unsigned val = (bits[bb] >> bs) & 0x03;
		      memory_set(rfp->mem->mem, bidx+idx, val);
		}

		delete[]bits;
		break;
	  }

	  case vpiBinStrVal: {
		unsigned char*bits = new unsigned char[(width+3) / 4];
		vpip_bin_str_to_bits(bits, width, val->value.str, false);

		for (unsigned idx = 0 ;  idx < width ;  idx += 1) {
		      unsigned bb = idx / 4;
		      unsigned bs = (idx % 4) * 2;
		      unsigned val = (bits[bb] >> bs) & 0x03;
		      memory_set(rfp->mem->mem, bidx+idx, val);
		}

		delete[]bits;
		break;
	  }

	  default:
	    assert(0);
      }

      return 0;
}

static char* memory_word_get_str(int code, vpiHandle ref)
{
      assert(ref->vpi_type->type_code==vpiMemoryWord);

      struct __vpiMemoryWord*rfp = (struct __vpiMemoryWord*)ref;

      char *bn = strdup(vpi_get_str(vpiFullName, &rfp->mem->scope->base));
      char *nm = memory_name(rfp->mem->mem);

      char *rbuf = need_result_buf(strlen(bn) + strlen(nm) + 10 + 4, RBUF_STR);

      switch (code) {
	  case vpiFullName:
	    sprintf(rbuf, "%s.%s[%d]", bn, nm, rfp->index.value);
	    free(bn);
	    return rbuf;
	    break;
	  case vpiName: {
	    sprintf(rbuf, "%s[%d]", nm, rfp->index.value);
	    free(bn);
	    return rbuf;
	    break;
	  }
      }

      free(bn);
      return 0;
}

static void memory_word_get_value(vpiHandle ref, s_vpi_value*vp)
{
      struct __vpiMemoryWord*rfp = (struct __vpiMemoryWord*)ref;
      assert(rfp->base.vpi_type->type_code==vpiMemoryWord);

      unsigned width = memory_data_width(rfp->mem->mem);
      unsigned word_offset = memory_root(rfp->mem->mem);
      unsigned bidx = (rfp->index.value - word_offset) * ((width+3)&~3);

      char *rbuf = 0;

      switch (vp->format) {
	  default:
	    assert("format not implemented");

	  case vpiBinStrVal:
	      rbuf = need_result_buf(width+1, RBUF_VAL);
	      for (unsigned idx = 0 ;  idx < width ;  idx += 1) {
		  unsigned bit = memory_get(rfp->mem->mem, bidx+idx);

		  rbuf[width-idx-1] = "01xz"[bit];
	      }
	      rbuf[width] = 0;
	      vp->value.str = rbuf;
	      break;

	  case vpiOctStrVal: {
		unsigned hwid = (width+2) / 3;
		unsigned char*bits = new unsigned char[width];

		for (unsigned idx = 0 ;  idx < width ;  idx += 1) {
		      unsigned bb = idx / 4;
		      unsigned bs = (idx % 4) * 2;
		      unsigned val = memory_get(rfp->mem->mem, bidx+idx);
		      if (bs == 0)
			    bits[bb] = val;
		      else
			    bits[bb] |= val << bs;
		}

		rbuf = need_result_buf(hwid+1, RBUF_VAL);
		vpip_bits_to_oct_str(bits, width, rbuf, hwid+1, false);

		delete[]bits;
		vp->value.str = rbuf;
		break;
	  }

	  case vpiHexStrVal: {
		unsigned hval, hwid;
		hwid = (width + 3) / 4;

		rbuf = need_result_buf(hwid+1, RBUF_VAL);
		rbuf[hwid] = 0;

		hval = 0;
		for (unsigned idx = 0 ;  idx < width ;  idx += 1) {
		    unsigned bit = memory_get(rfp->mem->mem, bidx+idx);
		    hval = hval | (bit << 2*(idx % 4));

		    if (idx%4 == 3) {
			hwid -= 1;
			rbuf[hwid] = hex_digits[hval];
			hval = 0;
		    }
		}

		if (hwid > 0) {
		    unsigned padd = 0;

		    hwid -= 1;
		    rbuf[hwid] = hex_digits[hval];
		    switch(rbuf[hwid]) {
		    case 'X': padd = 2; break;
		    case 'Z': padd = 3; break;
		    }
		    if (padd) {
			for (unsigned idx = width % 4; idx < 4; idx += 1) {
			    hval = hval | padd << 2*idx;
			}
			rbuf[hwid] = hex_digits[hval];
		    }
		}
		vp->value.str = rbuf;
		break;
	  }

	  case vpiDecStrVal: {
		unsigned char*bits = new unsigned char[width];

		for (unsigned idx = 0 ;  idx < width ;  idx += 1)
		      bits[idx] = memory_get(rfp->mem->mem, bidx+idx);

		rbuf = need_result_buf(width+1, RBUF_VAL);
		vpip_bits_to_dec_str(bits, width, rbuf, width+1, false);

		delete[]bits;
		vp->value.str = rbuf;
		break;
	  }

	  case vpiIntVal:
	    assert(width <= 8 * sizeof vp->value.integer);

	    vp->value.integer = 0;
	    for (unsigned idx = 0;  idx < width;  idx += 1) {

		  unsigned bit = memory_get(rfp->mem->mem, bidx+idx);
		  if (bit>1) {
			vp->value.integer = 0;
			break;
		  }

		  vp->value.integer |= bit << idx;
	    }
	    break;

	  case vpiVectorVal: {
		  unsigned hwid = (width - 1)/32 + 1;

		  rbuf = need_result_buf(hwid * sizeof(s_vpi_vecval), RBUF_VAL);
		  s_vpi_vecval *op = (p_vpi_vecval)rbuf;
		  vp->value.vector = op;

		  op->aval = op->bval = 0;
		  for (unsigned idx = 0 ;  idx < width ;  idx += 1) {
			switch (memory_get(rfp->mem->mem, bidx+idx)) {
			case 0:
			      op->aval &= ~(1 << idx % 32);
			      op->bval &= ~(1 << idx % 32);
			      break;
			case 1:
			      op->aval |=  (1 << idx % 32);
			      op->bval &= ~(1 << idx % 32);
			      break;
			case 2:
			      op->aval |= (1 << idx % 32);
			      op->bval |= (1 << idx % 32);
			      break;
			case 3:
			      op->aval &= ~(1 << idx % 32);
			      op->bval |=  (1 << idx % 32);
			      break;
			}
			if (!((idx+1) % 32) && (idx+1 < width)) {
			      op++;
			      op->aval = op->bval = 0;
			}
		  }
		  break;
	    }
      }
}

static const struct __vpirt vpip_memory_rt = {
      vpiMemory,
      vpi_memory_get,
      memory_get_str,
      0,
      0,
      memory_get_handle,
      memory_iterate,
      memory_index,
};

static const struct __vpirt vpip_memory_word_rt = {
      vpiMemoryWord,
      memory_word_get,
      memory_word_get_str,
      memory_word_get_value,
      memory_word_put,
      memory_word_get_handle,
      0,
      0,
};

static void memory_make_word_handles(struct __vpiMemory*rfp)
{
      if (rfp->words != 0)
	    return;

      unsigned word_count = memory_size(rfp->mem);
      unsigned word_offset = memory_root(rfp->mem);

      rfp->words = (struct __vpiMemoryWord*)
	    calloc(word_count, sizeof (struct __vpiMemoryWord));

      for (unsigned idx = 0 ;  idx < word_count ;  idx += 1) {
	    struct __vpiMemoryWord*cur = rfp->words + idx;
	    cur->base.vpi_type = &vpip_memory_word_rt;
	    cur->mem = rfp;
	    vpip_make_dec_const(&cur->index, idx + word_offset);
      }
}

vpiHandle vpip_make_memory(vvp_memory_t mem)
{
      struct __vpiMemory*obj = (struct __vpiMemory*)
	    malloc(sizeof(struct __vpiMemory));
      count_vpi_memories += 1;

      obj->base.vpi_type = &vpip_memory_rt;
      obj->scope = vpip_peek_current_scope();
      obj->mem = mem;
      vpip_make_dec_const(&obj->left_range, memory_left_range(mem));
      vpip_make_dec_const(&obj->right_range, memory_right_range(mem));
      vpip_make_dec_const(&obj->word_left_range, memory_word_left_range(mem));
      vpip_make_dec_const(&obj->word_right_range,memory_word_right_range(mem));

      obj->words = 0;

      return &(obj->base);
}

void vpip_memory_value_change(struct __vpiCallback*cbh,
			      vpiHandle ref)
{
      struct __vpiMemory*obj = (struct __vpiMemory*)ref;
      cbh->next = obj->mem->cb;
      obj->mem->cb = cbh;
}