/*
 * Copyright (c) 2003-2009, John Wiegley.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * - Neither the name of New Artisans LLC nor the names of its
 *   contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <system.hh>

#include "amount.h"
#include "commodity.h"
#include "annotate.h"
#include "pool.h"

namespace ledger {

void commodity_t::base_t::history_t::add_price(commodity_t&      source,
					       const datetime_t& date,
					       const amount_t&	 price,
					       const bool	 reflexive)
{
  DEBUG("commodity.prices.add", "add_price to " << source
	<< (reflexive ? " (secondary)" : " (primary)")
	<< " : " << date << ", " << price);

  history_map::iterator i = prices.find(date);
  if (i != prices.end()) {
    (*i).second = price;
  } else {
    std::pair<history_map::iterator, bool> result
      = prices.insert(history_map::value_type(date, price));
    assert(result.second);
  }

  if (reflexive) {
    amount_t inverse = price.inverted();
    inverse.set_commodity(const_cast<commodity_t&>(source));
    price.commodity().add_price(date, inverse, false);
  } else {
    DEBUG("commodity.prices.add",
	  "marking commodity " << source.symbol() << " as primary");
    source.add_flags(COMMODITY_PRIMARY);
  }
}

bool commodity_t::base_t::history_t::remove_price(const datetime_t& date)
{
  DEBUG("commodity.prices.add", "remove_price: " << date);

  history_map::size_type n = prices.erase(date);
  if (n > 0)
    return true;
  return false;
}

void commodity_t::base_t::varied_history_t::
  add_price(commodity_t&      source,
	    const datetime_t& date,
	    const amount_t&   price,
	    const bool	      reflexive)
{
  optional<history_t&> hist = history(price.commodity());
  if (! hist) {
    std::pair<history_by_commodity_map::iterator, bool> result
      = histories.insert(history_by_commodity_map::value_type
			 (&price.commodity(), history_t()));
    assert(result.second);

    hist = (*result.first).second;
  }
  assert(hist);

  hist->add_price(source, date, price, reflexive);
}

bool commodity_t::base_t::varied_history_t::
  remove_price(const datetime_t& date,
	       commodity_t&      comm)
{
  DEBUG("commodity.prices.add", "varied_remove_price: " << date << ", " << comm);

  if (optional<history_t&> hist = history(comm))
    return hist->remove_price(date);
  return false;
}

optional<price_point_t>
  commodity_t::base_t::history_t::
    find_price(const optional<datetime_t>& moment,
	       const optional<datetime_t>& oldest
#if defined(DEBUG_ON)
	       , const int indent
#endif
	       ) const
{
  price_point_t point;
  bool          found = false;

#define DEBUG_INDENT(cat, indent)		\
  do {						\
    if (SHOW_DEBUG(cat))			\
      for (int i = 0; i < indent; i++)		\
	ledger::_log_buffer << "  ";		\
  } while (false)

#if defined(DEBUG_ON)
  DEBUG_INDENT("commodity.prices.find", indent);
  if (moment)
    DEBUG("commodity.prices.find", "find price nearest before or on: " << *moment);
  else
    DEBUG("commodity.prices.find", "find any price");

  if (oldest) {
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find", "  but no older than: " << *oldest);
  }
#endif

  if (prices.size() == 0) {
#if defined(DEBUG_ON)
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find", "  there are no prices in this history");
#endif
    return none;
  }

  if (! moment) {
    history_map::const_reverse_iterator r = prices.rbegin();
    point.when	= (*r).first;
    point.price = (*r).second;
    found = true;
#if defined(DEBUG_ON)
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find", "  using most recent price");
#endif
  } else {
    history_map::const_iterator i = prices.lower_bound(*moment);
    if (i == prices.end()) {
      history_map::const_reverse_iterator r = prices.rbegin();
      point.when  = (*r).first;
      point.price = (*r).second;
      found = true;
#if defined(DEBUG_ON)
      DEBUG_INDENT("commodity.prices.find", indent);
      DEBUG("commodity.prices.find", "  using last price");
#endif
    } else {
      point.when = (*i).first;
      if (*moment < point.when) {
	if (i != prices.begin()) {
	  --i;
	  point.when  = (*i).first;
	  point.price = (*i).second;
	  found = true;
	}
      } else {
	point.price = (*i).second;
	found = true;
      }
#if defined(DEBUG_ON)
      DEBUG_INDENT("commodity.prices.find", indent);
      DEBUG("commodity.prices.find", "  using found price");
#endif
    }
  }

  if (! found) {
#if defined(DEBUG_ON)
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find", "  could not find a price");
#endif
    return none;
  }
  else if (moment && point.when > *moment) {
#if defined(DEBUG_ON)
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find", "  price is too young ");
#endif
    return none;
  }
  else if (oldest && point.when < *oldest) {
#if defined(DEBUG_ON)
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find", "  price is too old ");
#endif
    return none;
  }
  else {
#if defined(DEBUG_ON)
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find",
	  "  returning price: " << point.when << ", " << point.price);
#endif
    return point;
  }
}

optional<price_point_t>
  commodity_t::base_t::varied_history_t::
    find_price(const commodity_t&            source,
	       const optional<commodity_t&>& commodity,
	       const optional<datetime_t>&   moment,
	       const optional<datetime_t>&   oldest
#if defined(DEBUG_ON)
	       , const int indent
#endif
	       ) const
{
  optional<price_point_t> point;
  optional<datetime_t>	  limit = oldest;

  assert(! commodity || source != *commodity);

#if defined(DEBUG_ON)
  DEBUG_INDENT("commodity.prices.find", indent);
  DEBUG("commodity.prices.find", "varied_find_price for: " << source);

  DEBUG_INDENT("commodity.prices.find", indent);
  if (commodity)
    DEBUG("commodity.prices.find", "  looking for: commodity '" << *commodity << "'");
  else
    DEBUG("commodity.prices.find", "  looking for: any commodity");

  if (moment) {
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find", "  time index: " << *moment);
  }

  if (oldest) {
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find", "  only consider prices younger than: " << *oldest);
  }
#endif

  // Either we couldn't find a history for the target commodity, or we
  // couldn't find a price.  In either case, search all histories known
  // to this commodity for a price which we can calculate in terms of
  // the goal commodity.
  price_point_t best;
  bool          found = false;

  foreach (history_by_commodity_map::value_type hist, histories) {
    commodity_t& comm(*hist.first);
    if (comm == source)
      continue;

#if defined(DEBUG_ON)
    DEBUG_INDENT("commodity.prices.find", indent + 1);
    DEBUG("commodity.prices.find",
	  "  searching for price via commodity '" << comm << "'");
#endif

    point = hist.second.find_price(moment, limit
#if defined(DEBUG_ON)
				   , indent + 2
#endif
				   );
    assert(! point || point->price.commodity() == comm);

    if (point) {
      optional<price_point_t> xlat;

      if (commodity && comm != *commodity) {
#if defined(DEBUG_ON)
	DEBUG_INDENT("commodity.prices.find", indent + 1);
	DEBUG("commodity.prices.find", "  looking for translation price");
#endif

	xlat = comm.find_price(commodity, moment, limit
#if defined(DEBUG_ON)
			       , indent + 2
#endif
			       );
	if (xlat) {
#if defined(DEBUG_ON)
	  DEBUG_INDENT("commodity.prices.find", indent + 1);
	  DEBUG("commodity.prices.find", "  found translated price "
		<< xlat->price << " from " << xlat->when);
#endif

	  point->price = xlat->price * point->price;
	  if (xlat->when < point->when) {
	    point->when = xlat->when;
#if defined(DEBUG_ON)
	    DEBUG_INDENT("commodity.prices.find", indent + 1);
	    DEBUG("commodity.prices.find",
		  "  adjusting date of result back to " << point->when);
#endif
	  }
	} else {
#if defined(DEBUG_ON)
	  DEBUG_INDENT("commodity.prices.find", indent + 1);
	  DEBUG("commodity.prices.find", "  saw no translated price there");
#endif
	  continue;
	}
      }

      assert(! commodity || point->price.commodity() == *commodity);
#if defined(DEBUG_ON)
      DEBUG_INDENT("commodity.prices.find", indent + 1);
      DEBUG("commodity.prices.find",
	    "  saw a price there: " << point->price << " from " << point->when);
#endif
      if (! limit || point->when > *limit) {
	limit = point->when;
	best  = *point;
	found = true;
      }
    } else {
#if defined(DEBUG_ON)
      DEBUG_INDENT("commodity.prices.find", indent + 1);
      DEBUG("commodity.prices.find", "  saw no price there");
#endif
    }
  }

  if (found) {
#if defined(DEBUG_ON)
    DEBUG_INDENT("commodity.prices.find", indent);
    DEBUG("commodity.prices.find",
	  "  found price " << best.price << " from " << best.when);
    DEBUG("commodity.download",
	  "found price " << best.price << " from " << best.when);
#endif
    return best;
  }
  return none;
}

optional<commodity_t::base_t::history_t&>
  commodity_t::base_t::varied_history_t::
    history(const optional<commodity_t&>& commodity)
{
  commodity_t * comm = NULL;
  if (! commodity) {
    if (histories.size() > 1)
      return none;
#if 0
      // jww (2008-09-20): Document which option switch to use here
      throw_(commodity_error,
	     _("Cannot determine price history: "
	       "prices known for multiple commodities (use -x)"));
#endif
    comm = (*histories.begin()).first;
  } else {
    comm = &(*commodity);
  }

  history_by_commodity_map::iterator i = histories.find(comm);
  if (i != histories.end())
    return (*i).second;

  return none;
}

optional<price_point_t>
commodity_t::check_for_updated_price(const optional<price_point_t>& point,
				     const optional<datetime_t>&    moment,
				     const optional<commodity_t&>&  in_terms_of)
{
  if (parent().get_quotes && ! has_flags(COMMODITY_NOMARKET)) {
    bool exceeds_leeway = true;

    if (point) {
      time_duration_t::sec_type seconds_diff;
      if (moment) {
	seconds_diff = (*moment - point->when).total_seconds();
	DEBUG("commodity.download", "moment = " << *moment);
	DEBUG("commodity.download", "slip.moment = " << seconds_diff);
      } else {
	seconds_diff = (TRUE_CURRENT_TIME() - point->when).total_seconds();
	DEBUG("commodity.download", "slip.now = " << seconds_diff);
      }

      DEBUG("commodity.download", "leeway = " << parent().quote_leeway);
      if (seconds_diff < parent().quote_leeway)
	exceeds_leeway = false;
    }

    if (exceeds_leeway) {
      DEBUG("commodity.download",
	    "attempting to download a more current quote...");
      if (optional<price_point_t> quote =
	  parent().get_commodity_quote(*this, in_terms_of)) {
	if (! in_terms_of ||
	    (quote->price.has_commodity() &&
	     quote->price.commodity() == *in_terms_of))
	  return quote;
      }
    }
  }
  return point;
}

commodity_t::operator bool() const
{
  return this != parent().null_commodity;
}

bool commodity_t::symbol_needs_quotes(const string& symbol)
{
  foreach (char ch, symbol)
    if (std::isspace(ch) || std::isdigit(ch) || ch == '-' || ch == '.')
      return true;

  return false;
}

namespace {
  bool is_reserved_token(const char * buf)
  {
    switch (buf[0]) {
    case 'a':
      return std::strcmp(buf, "and") == 0;
    case 'd':
      return std::strcmp(buf, "div") == 0;
    case 'e':
      return std::strcmp(buf, "else") == 0;
    case 'f':
      return std::strcmp(buf, "false") == 0;
    case 'i':
      return std::strcmp(buf, "if") == 0;
    case 'o':
      return std::strcmp(buf, "or") == 0;
    case 'n':
      return std::strcmp(buf, "not") == 0;
    case 't':
      return std::strcmp(buf, "true") == 0;
    }
    return false;
  }
}

void commodity_t::parse_symbol(std::istream& in, string& symbol)
{
  // Invalid commodity characters:
  //   SPACE, TAB, NEWLINE, RETURN
  //   0-9 . , ; - + * / ^ ? : & | ! =
  //   < > { } [ ] ( ) @

  static int invalid_chars[256] = {
          /* 0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f */
    /* 00 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0,
    /* 10 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* 20 */ 1, 1, 0, 0, 0, 0, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1,
    /* 30 */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
    /* 40 */ 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* 50 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0,
    /* 60 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* 70 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1,
    /* 80 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* 90 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* a0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* b0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* c0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* d0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* e0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
    /* f0 */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
  };

  istream_pos_type pos = in.tellg();

  char buf[256];
  char c = peek_next_nonws(in);
  if (c == '"') {
    in.get(c);
    READ_INTO(in, buf, 255, c, c != '"');
    if (c == '"')
      in.get(c);
    else
      throw_(amount_error, _("Quoted commodity symbol lacks closing quote"));
  } else {
    char * _p = buf;
    c = static_cast<char>(in.peek());
    while (_p - buf < 255 && in.good() && ! in.eof() && c != '\n') {
      std::size_t    bytes = 0;
      std::ptrdiff_t size  = _p - buf;
      unsigned char  d	   = c;

      // Check for the start of a UTF-8 multi-byte encoded string
      if (d >= 192 && d <= 223 && size < 254)
	bytes = 2;
      else if (d >= 224 && d <= 239 && size < 253)
	bytes = 3;
      else if (d >= 240 && d <= 247 && size < 252)
	bytes = 4;
      else if (d >= 248 && d <= 251 && size < 251)
	bytes = 5;
      else if (d >= 252 && d <= 253 && size < 250)
	bytes = 6;
      else if (d >= 254) // UTF-8 encoding error
	break;

      if (bytes > 0) {		// we're looking at a UTF-8 encoding
	for (std::size_t i = 0; i < bytes; i++) {
	  in.get(c);
	  if (in.bad() || in.eof())
	    break;
	  *_p++ = c;
	}
      }
      else if (invalid_chars[static_cast<unsigned char>(c)]) {
	break;
      }
      else {
	in.get(c);
	if (in.eof())
	  break;
	if (c == '\\') {
	  in.get(c);
	  if (in.eof())
	    break;
	}
	*_p++ = c;
      }

      c = static_cast<char>(in.peek());
    }
    *_p = '\0';

    if (is_reserved_token(buf))
      buf[0] = '\0';
  }
  symbol = buf;

  if (symbol.length() == 0) {
    in.clear();
    in.seekg(pos, std::ios::beg);
  }
}

void commodity_t::parse_symbol(char *& p, string& symbol)
{
  if (*p == '"') {
    char * q = std::strchr(p + 1, '"');
    if (! q)
      throw_(amount_error, _("Quoted commodity symbol lacks closing quote"));
    symbol = string(p + 1, 0, q - p - 1);
    p = q + 2;
  } else {
    char * q = next_element(p);
    symbol = p;
    if (q)
      p = q;
    else
      p += symbol.length();
  }
  if (symbol.empty())
    throw_(amount_error, _("Failed to parse commodity"));
}

bool commodity_t::valid() const
{
  if (symbol().empty() && this != parent().null_commodity) {
    DEBUG("ledger.validate",
	   "commodity_t: symbol().empty() && this != null_commodity");
    return false;
  }

  if (annotated && ! base) {
    DEBUG("ledger.validate", "commodity_t: annotated && ! base");
    return false;
  }

  if (precision() > 16) {
    DEBUG("ledger.validate", "commodity_t: precision() > 16");
    return false;
  }

  return true;
}

bool compare_amount_commodities::operator()(const amount_t * left,
					    const amount_t * right) const
{
  commodity_t& leftcomm(left->commodity());
  commodity_t& rightcomm(right->commodity());

  DEBUG("commodity.compare", " left symbol (" << leftcomm << ")");
  DEBUG("commodity.compare", "right symbol (" << rightcomm << ")");

  int cmp = leftcomm.base_symbol().compare(rightcomm.base_symbol());
  if (cmp != 0)
    return cmp < 0;

  if (! leftcomm.annotated) {
    return rightcomm.annotated;
  }
  else if (! rightcomm.annotated) {
    return ! leftcomm.annotated;
  }
  else {
    annotated_commodity_t& aleftcomm(static_cast<annotated_commodity_t&>(leftcomm));
    annotated_commodity_t& arightcomm(static_cast<annotated_commodity_t&>(rightcomm));

    if (! aleftcomm.details.price && arightcomm.details.price)
      return true;
    if (aleftcomm.details.price && ! arightcomm.details.price)
      return false;

    if (aleftcomm.details.price && arightcomm.details.price) {
      amount_t leftprice(*aleftcomm.details.price);
      amount_t rightprice(*arightcomm.details.price);

      if (leftprice.commodity() == rightprice.commodity()) {
	return (leftprice - rightprice).sign() < 0;
      } else {
	// Since we have two different amounts, there's really no way
	// to establish a true sorting order; we'll just do it based
	// on the numerical values.
	leftprice.clear_commodity();
	rightprice.clear_commodity();
	return (leftprice - rightprice).sign() < 0;
      }
    }

    if (! aleftcomm.details.date && arightcomm.details.date)
      return true;
    if (aleftcomm.details.date && ! arightcomm.details.date)
      return false;

    if (aleftcomm.details.date && arightcomm.details.date) {
      date_duration_t diff = *aleftcomm.details.date - *arightcomm.details.date;
      return diff.is_negative();
    }

    if (! aleftcomm.details.tag && arightcomm.details.tag)
      return true;
    if (aleftcomm.details.tag && ! arightcomm.details.tag)
      return false;

    if (aleftcomm.details.tag && arightcomm.details.tag)
      return *aleftcomm.details.tag < *arightcomm.details.tag;

    assert(false);
    return true;
  }
}

} // namespace ledger
