/*
 * Copyright (c) 2003-2023, 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.
 */

/**
 * @addtogroup report
 */

/**
 * @file   filters.h
 * @author John Wiegley
 *
 * @ingroup report
 */
#pragma once

#include "chain.h"
#include "xact.h"
#include "post.h"
#include "account.h"
#include "temps.h"

namespace ledger {

using namespace boost::placeholders;

//////////////////////////////////////////////////////////////////////
//
// Posting collector
//

class post_splitter : public item_handler<post_t>
{
public:
  typedef std::map<value_t, posts_list> value_to_posts_map;
  typedef function<void (const value_t&)> custom_flusher_t;

protected:
  value_to_posts_map         posts_map;
  post_handler_ptr           post_chain;
  report_t&                  report;
  expr_t&                    group_by_expr;
  custom_flusher_t           preflush_func;
  optional<custom_flusher_t> postflush_func;

public:
  post_splitter(post_handler_ptr _post_chain,
                report_t&        _report,
                expr_t&          _group_by_expr)
    : post_chain(_post_chain), report(_report),
      group_by_expr(_group_by_expr) {
    preflush_func = bind(&post_splitter::print_title, this, _1);
    TRACE_CTOR(post_splitter, "scope_t&, post_handler_ptr, expr_t");
  }
  virtual ~post_splitter() {
    TRACE_DTOR(post_splitter);
  }

  void set_preflush_func(custom_flusher_t functor) {
    preflush_func = functor;
  }
  void set_postflush_func(custom_flusher_t functor) {
    postflush_func = functor;
  }

  virtual void print_title(const value_t& val);

  virtual void flush();
  virtual void operator()(post_t& post);

  virtual void clear() {
    posts_map.clear();
    post_chain->clear();
    item_handler<post_t>::clear();
  }
};

//////////////////////////////////////////////////////////////////////
//
// Posting filters
//

class ignore_posts : public item_handler<post_t>
{
public:
  virtual void operator()(post_t&) {}
};

class collect_posts : public item_handler<post_t>
{
public:
  std::vector<post_t *> posts;

  collect_posts() : item_handler<post_t>() {
    TRACE_CTOR(collect_posts, "");
  }
  virtual ~collect_posts() {
    TRACE_DTOR(collect_posts);
  }

  std::size_t length() const {
    return posts.size();
  }

  std::vector<post_t *>::iterator begin() {
    return posts.begin();
  }
  std::vector<post_t *>::iterator end() {
    return posts.end();
  }

  virtual void flush() {}
  virtual void operator()(post_t& post) {
    posts.push_back(&post);
  }

  virtual void clear() {
    posts.clear();
    item_handler<post_t>::clear();
  }
};

template <typename Iterator>
class pass_down_posts : public item_handler<post_t>
{
  pass_down_posts();

public:
  pass_down_posts(post_handler_ptr handler, Iterator& iter)
    : item_handler<post_t>(handler) {
    while (post_t * post = *iter) {
      try {
        item_handler<post_t>::operator()(*post);
      }
      catch (const std::exception&) {
        add_error_context(item_context(*post, _("While handling posting")));
        throw;
      }
      iter.increment();
    }

    item_handler<post_t>::flush();

    TRACE_CTOR(pass_down_posts, "post_handler_ptr, posts_iterator");
  }

  virtual ~pass_down_posts() {
    TRACE_DTOR(pass_down_posts);
  }
};

class push_to_posts_list : public item_handler<post_t>
{
  push_to_posts_list();

public:
  posts_list& posts;

  push_to_posts_list(posts_list& _posts) : posts(_posts) {
    TRACE_CTOR(push_to_posts_list, "posts_list&");
  }
  virtual ~push_to_posts_list() {
    TRACE_DTOR(push_to_posts_list);
  }

  virtual void operator()(post_t& post) {
    posts.push_back(&post);
  }
};

class truncate_xacts : public item_handler<post_t>
{
  int  head_count;
  int  tail_count;
  bool completed;

  posts_list  posts;
  std::size_t xacts_seen;
  xact_t *    last_xact;

  truncate_xacts();

public:
  truncate_xacts(post_handler_ptr handler,
                 int _head_count, int _tail_count)
    : item_handler<post_t>(handler),
      head_count(_head_count), tail_count(_tail_count),
      completed(false), xacts_seen(0), last_xact(NULL) {
    TRACE_CTOR(truncate_xacts, "post_handler_ptr, int, int");
  }
  virtual ~truncate_xacts() {
    TRACE_DTOR(truncate_xacts);
  }

  virtual void flush();
  virtual void operator()(post_t& post);

  virtual void clear() {
    completed = false;
    posts.clear();
    xacts_seen = 0;
    last_xact = NULL;

    item_handler<post_t>::clear();
  }
};

class sort_posts : public item_handler<post_t>
{
  typedef std::deque<post_t *> posts_deque;

  posts_deque posts;
  expr_t      sort_order;
  report_t&   report;

  sort_posts();

public:
  sort_posts(post_handler_ptr handler, const expr_t& _sort_order,
             report_t& _report)
    : item_handler<post_t>(handler), sort_order(_sort_order), report(_report) {
    TRACE_CTOR(sort_posts, "post_handler_ptr, const value_expr&, report_t&");
  }
  sort_posts(post_handler_ptr handler, const string& _sort_order,
             report_t& _report)
    : item_handler<post_t>(handler), sort_order(_sort_order), report(_report) {
    TRACE_CTOR(sort_posts, "post_handler_ptr, const string&, report_t&");
  }
  virtual ~sort_posts() {
    TRACE_DTOR(sort_posts);
  }

  virtual void post_accumulated_posts();

  virtual void flush() {
    post_accumulated_posts();
    item_handler<post_t>::flush();
  }

  virtual void operator()(post_t& post) {
    posts.push_back(&post);
  }

  virtual void clear() {
    posts.clear();
    sort_order.mark_uncompiled();

    item_handler<post_t>::clear();
  }
};

class sort_xacts : public item_handler<post_t>
{
  sort_posts sorter;
  xact_t *  last_xact;

  sort_xacts();

public:
  sort_xacts(post_handler_ptr handler, const expr_t& _sort_order,
             report_t& _report)
    : sorter(handler, _sort_order, _report) {
    TRACE_CTOR(sort_xacts,
               "post_handler_ptr, const value_expr&, report_t&");
  }
  sort_xacts(post_handler_ptr handler, const string& _sort_order,
             report_t& _report)
    : sorter(handler, _sort_order, _report) {
    TRACE_CTOR(sort_xacts,
               "post_handler_ptr, const string&, report_t&");
  }
  virtual ~sort_xacts() {
    TRACE_DTOR(sort_xacts);
  }

  virtual void flush() {
    sorter.flush();
    item_handler<post_t>::flush();
  }

  virtual void operator()(post_t& post) {
    if (last_xact && post.xact != last_xact)
      sorter.post_accumulated_posts();

    sorter(post);

    last_xact = post.xact;
  }

  virtual void clear() {
    sorter.clear();
    last_xact = NULL;

    item_handler<post_t>::clear();
  }
};

class filter_posts : public item_handler<post_t>
{
  predicate_t pred;
  scope_t&    context;

  filter_posts();

public:
  filter_posts(post_handler_ptr   handler,
               const predicate_t& predicate,
               scope_t&           _context)
    : item_handler<post_t>(handler), pred(predicate), context(_context) {
    TRACE_CTOR(filter_posts, "post_handler_ptr, predicate_t, scope_t&");
  }
  virtual ~filter_posts() {
    TRACE_DTOR(filter_posts);
  }

  virtual void operator()(post_t& post) {
    bind_scope_t bound_scope(context, post);
    if (pred(bound_scope)) {
      post.xdata().add_flags(POST_EXT_MATCHES);
      (*handler)(post);
    }
  }

  virtual void clear() {
    pred.mark_uncompiled();
    item_handler<post_t>::clear();
  }
};

class anonymize_posts : public item_handler<post_t>
{
  typedef std::map<commodity_t *, std::size_t>        commodity_index_map;
  typedef variate_generator<mt19937&, uniform_int<> > int_generator_t;

  temporaries_t       temps;
  commodity_index_map comms;
  std::size_t         next_comm_id;
  xact_t *            last_xact;
  mt19937             rnd_gen;
  uniform_int<>       integer_range;
  int_generator_t     integer_gen;

  anonymize_posts();

public:
  anonymize_posts(post_handler_ptr handler)
    : item_handler<post_t>(handler), next_comm_id(0), last_xact(NULL),
      rnd_gen(static_cast<unsigned int>(static_cast<boost::uintmax_t>(std::time(0)))),
      integer_range(1, 2000000000L),
      integer_gen(rnd_gen, integer_range) {
    TRACE_CTOR(anonymize_posts, "post_handler_ptr");
  }
  virtual ~anonymize_posts() {
    TRACE_DTOR(anonymize_posts);
    handler.reset();
  }

  void render_commodity(amount_t& amt);

  virtual void operator()(post_t& post);

  virtual void clear() {
    temps.clear();
    comms.clear();
    last_xact = NULL;

    item_handler<post_t>::clear();
  }
};

class calc_posts : public item_handler<post_t>
{
  post_t * last_post;
  expr_t&  amount_expr;
  bool     calc_running_total;

  calc_posts();

public:
  calc_posts(post_handler_ptr handler,
             expr_t&          _amount_expr,
             bool             _calc_running_total = false)
    : item_handler<post_t>(handler), last_post(NULL),
      amount_expr(_amount_expr), calc_running_total(_calc_running_total) {
    TRACE_CTOR(calc_posts, "post_handler_ptr, expr_t&, bool");
  }
  virtual ~calc_posts() {
    TRACE_DTOR(calc_posts);
  }

  virtual void operator()(post_t& post);

  virtual void clear() {
    last_post = NULL;
    amount_expr.mark_uncompiled();

    item_handler<post_t>::clear();
  }
};

class collapse_posts : public item_handler<post_t>
{

  typedef std::map<account_t *,value_t> totals_map;

  expr_t&             amount_expr;
  predicate_t         display_predicate;
  predicate_t         only_predicate;
  value_t             subtotal;
  std::size_t         count;
  xact_t *            last_xact;
  post_t *            last_post;
  temporaries_t       temps;
  account_t *         global_totals_account;
  totals_map          totals;
  bool                only_collapse_if_zero;
  unsigned short      collapse_depth;
  std::list<post_t *> component_posts;
  report_t&           report;

  collapse_posts();

public:
  collapse_posts(post_handler_ptr handler,
                 report_t&        _report,
                 expr_t&          _amount_expr,
                 predicate_t      _display_predicate,
                 predicate_t      _only_predicate,
                 bool             _only_collapse_if_zero = false,
                 unsigned short   _collapse_depth = 0)
    : item_handler<post_t>(handler), amount_expr(_amount_expr),
      display_predicate(_display_predicate),
      only_predicate(_only_predicate), count(0),
      last_xact(NULL), last_post(NULL),
      only_collapse_if_zero(_only_collapse_if_zero),
      collapse_depth(_collapse_depth), report(_report) {
    create_accounts();
    TRACE_CTOR(collapse_posts, "post_handler_ptr, ...");
  }
  virtual ~collapse_posts() {
    TRACE_DTOR(collapse_posts);
    handler.reset();
  }

  void create_accounts() {
    global_totals_account = &temps.create_account(_("<Total>"));
  }

  value_t& find_totals(account_t* account);

  virtual void flush() {
    report_subtotal();
    item_handler<post_t>::flush();
  }

  void report_subtotal();

  virtual void operator()(post_t& post);

  virtual void clear() {
    amount_expr.mark_uncompiled();
    display_predicate.mark_uncompiled();
    only_predicate.mark_uncompiled();

    subtotal  = value_t();
    count     = 0;
    last_xact = NULL;
    last_post = NULL;

    temps.clear();
    create_accounts();
    totals.clear();
    component_posts.clear();

    item_handler<post_t>::clear();
  }
};

class related_posts : public item_handler<post_t>
{
  posts_list posts;
  bool       also_matching;

  related_posts();

public:
  related_posts(post_handler_ptr handler,
                       const bool _also_matching = false)
    : item_handler<post_t>(handler),
      also_matching(_also_matching) {
    TRACE_CTOR(related_posts, "post_handler_ptr, const bool");
  }
  virtual ~related_posts() throw() {
    TRACE_DTOR(related_posts);
  }

  virtual void flush();
  virtual void operator()(post_t& post) {
    post.xdata().add_flags(POST_EXT_RECEIVED);
    posts.push_back(&post);
  }

  virtual void clear() {
    posts.clear();
    item_handler<post_t>::clear();
  }
};

class display_filter_posts : public item_handler<post_t>
{
  // This filter requires that calc_posts be used at some point
  // later in the chain.

  report_t&     report;
  expr_t&       display_amount_expr;
  expr_t&       display_total_expr;
  bool          show_rounding;
  value_t       last_display_total;
  temporaries_t temps;
  account_t *   rounding_account;

  display_filter_posts();

public:
  account_t *   revalued_account;

  display_filter_posts(post_handler_ptr handler,
                       report_t&        _report,
                       bool             _show_rounding);

  virtual ~display_filter_posts() {
    TRACE_DTOR(display_filter_posts);
    handler.reset();
  }

  void create_accounts() {
    rounding_account = &temps.create_account(_("<Adjustment>"));
    revalued_account = &temps.create_account(_("<Revalued>"));
  }

  bool output_rounding(post_t& post);

  virtual void operator()(post_t& post);

  virtual void clear() {
    display_amount_expr.mark_uncompiled();
    display_total_expr.mark_uncompiled();

    last_display_total = value_t();

    temps.clear();
    item_handler<post_t>::clear();

    create_accounts();
  }
};

class changed_value_posts : public item_handler<post_t>
{
  // This filter requires that calc_posts be used at some point
  // later in the chain.

  report_t&     report;
  expr_t&       total_expr;
  expr_t&       display_total_expr;
  bool          changed_values_only;
  bool          historical_prices_only;
  bool          for_accounts_report;
  bool          show_unrealized;
  post_t *      last_post;
  value_t       last_total;
  value_t       repriced_total;
  temporaries_t temps;
  account_t *   revalued_account;
  account_t *   gains_equity_account;
  account_t *   losses_equity_account;

  display_filter_posts * display_filter;

  changed_value_posts();

public:
  changed_value_posts(post_handler_ptr       handler,
                      report_t&              _report,
                      bool                   _for_accounts_report,
                      bool                   _show_unrealized,
                      display_filter_posts * _display_filter);

  virtual ~changed_value_posts() {
    TRACE_DTOR(changed_value_posts);
    temps.clear();
    handler.reset();
  }

  void create_accounts() {
    revalued_account = (display_filter ? display_filter->revalued_account :
                        &temps.create_account(_("<Revalued>")));
  }

  virtual void flush();

  void output_revaluation(post_t& post, const date_t& current);
  void output_intermediate_prices(post_t& post, const date_t& current);

  virtual void operator()(post_t& post);

  virtual void clear() {
    total_expr.mark_uncompiled();
    display_total_expr.mark_uncompiled();

    last_post = NULL;
    last_total = value_t();

    temps.clear();
    item_handler<post_t>::clear();

    create_accounts();
  }
};

class subtotal_posts : public item_handler<post_t>
{
  subtotal_posts();

protected:
  class acct_value_t
  {
    acct_value_t();

  public:
    account_t * account;
    value_t     value;
    bool        is_virtual;
    bool        must_balance;

    acct_value_t(account_t * a, bool _is_virtual = false,
                 bool _must_balance = false)
      : account(a), is_virtual(_is_virtual), must_balance(_must_balance) {
      TRACE_CTOR(acct_value_t, "account_t *, bool, bool");
    }
    acct_value_t(account_t * a, value_t& v, bool _is_virtual = false,
                 bool _must_balance = false)
      : account(a), value(v), is_virtual(_is_virtual),
        must_balance(_must_balance) {
      TRACE_CTOR(acct_value_t, "account_t *, value_t&, bool, bool");
    }
    acct_value_t(const acct_value_t& av)
      : account(av.account), value(av.value), is_virtual(av.is_virtual),
        must_balance(av.must_balance) {
      TRACE_CTOR(acct_value_t, "copy");
    }
    ~acct_value_t() throw() {
      TRACE_DTOR(acct_value_t);
    }
  };

  typedef std::map<string, acct_value_t>  values_map;
  typedef std::pair<string, acct_value_t> values_pair;

protected:
  expr_t&              amount_expr;
  values_map           values;
  optional<string>     date_format;
  temporaries_t        temps;
  std::deque<post_t *> component_posts;

public:
  subtotal_posts(post_handler_ptr handler, expr_t& _amount_expr,
                 const optional<string>& _date_format = none)
    : item_handler<post_t>(handler), amount_expr(_amount_expr),
      date_format(_date_format) {
    TRACE_CTOR(subtotal_posts,
               "post_handler_ptr, expr_t&, const optional<string>&");
  }
  virtual ~subtotal_posts() {
    TRACE_DTOR(subtotal_posts);
    handler.reset();
  }

  void report_subtotal(const char * spec_fmt = NULL,
                       const optional<date_interval_t>& interval = none);

  virtual void flush() {
    if (values.size() > 0)
      report_subtotal();
    item_handler<post_t>::flush();
  }
  virtual void operator()(post_t& post);

  virtual void clear() {
    amount_expr.mark_uncompiled();
    values.clear();
    temps.clear();
    component_posts.clear();

    item_handler<post_t>::clear();
  }
};

class interval_posts : public subtotal_posts
{
  date_interval_t start_interval;
  date_interval_t interval;
  account_t *     empty_account;
  bool            exact_periods;
  bool            generate_empty_posts;
  bool            align_intervals;

  std::deque<post_t *> all_posts;

  interval_posts();

public:

  interval_posts(post_handler_ptr       _handler,
                 expr_t&                amount_expr,
                 const date_interval_t& _interval,
                 bool                   _exact_periods        = false,
                 bool                   _generate_empty_posts = false,
                 bool                   _align_intervals      = false)
    : subtotal_posts(_handler, amount_expr), start_interval(_interval),
      interval(start_interval), exact_periods(_exact_periods),
      generate_empty_posts(_generate_empty_posts),
      align_intervals(_align_intervals) {
    create_accounts();
    TRACE_CTOR(interval_posts,
               "post_handler_ptr, expr_t&, date_interval_t, bool, bool");
  }
  virtual ~interval_posts() throw() {
    TRACE_DTOR(interval_posts);
  }

  void create_accounts() {
    empty_account = &temps.create_account(_("<None>"));
  }

  void report_subtotal(const date_interval_t& ival);

#if DEBUG_ON
  void debug_interval(const date_interval_t& ival) {
    if (ival.start)
      DEBUG("filters.interval", "start  = " << *ival.start);
    else
      DEBUG("filters.interval", "no start");

    if (ival.finish)
      DEBUG("filters.interval", "finish = " << *ival.finish);
    else
      DEBUG("filters.interval", "no finish");
  }
#endif

  virtual void operator()(post_t& post);
  virtual void flush();

  virtual void clear() {
    interval  = start_interval;

    subtotal_posts::clear();
    create_accounts();
  }
};

class posts_as_equity : public subtotal_posts
{
  report_t&   report;
  post_t *    last_post;
  account_t * equity_account;
  account_t * balance_account;
  bool        unround;

  posts_as_equity();

public:
  posts_as_equity(post_handler_ptr _handler, report_t& _report,
                  expr_t& amount_expr, bool _unround)
    : subtotal_posts(_handler, amount_expr), report(_report), unround(_unround) {
    create_accounts();
    TRACE_CTOR(posts_as_equity, "post_handler_ptr, expr_t&");
  }
  virtual ~posts_as_equity() throw() {
    TRACE_DTOR(posts_as_equity);
  }

  void create_accounts() {
    equity_account  = &temps.create_account(_("Equity"));
    balance_account = equity_account->find_account(_("Opening Balances"));
  }

  void report_subtotal();

  virtual void flush() {
    report_subtotal();
    subtotal_posts::flush();
  }

  virtual void clear() {
    last_post = NULL;
    subtotal_posts::clear();
    create_accounts();
  }
};

class by_payee_posts : public item_handler<post_t>
{
  typedef std::map<string, shared_ptr<subtotal_posts> >  payee_subtotals_map;
  typedef std::pair<string, shared_ptr<subtotal_posts> > payee_subtotals_pair;

  expr_t&             amount_expr;
  payee_subtotals_map payee_subtotals;

  by_payee_posts();

 public:
  by_payee_posts(post_handler_ptr handler, expr_t& _amount_expr)
    : item_handler<post_t>(handler), amount_expr(_amount_expr) {
    TRACE_CTOR(by_payee_posts, "post_handler_ptr, expr_t&");
  }
  virtual ~by_payee_posts() {
    TRACE_DTOR(by_payee_posts);
  }

  virtual void flush();
  virtual void operator()(post_t& post);

  virtual void clear() {
    amount_expr.mark_uncompiled();
    payee_subtotals.clear();

    item_handler<post_t>::clear();
  }
};

class transfer_details : public item_handler<post_t>
{
  account_t *   master;
  expr_t        expr;
  scope_t&      scope;
  temporaries_t temps;

  transfer_details();

public:
  enum element_t {
    SET_DATE,
    SET_ACCOUNT,
    SET_PAYEE
  } which_element;

  transfer_details(post_handler_ptr handler,
                   element_t        _which_element,
                   account_t *      _master,
                   const expr_t&    _expr,
                   scope_t&         _scope)
    : item_handler<post_t>(handler), master(_master),
      expr(_expr), scope(_scope), which_element(_which_element) {
    TRACE_CTOR(transfer_details,
               "post_handler_ptr, element_t, account_t *, expr_t, scope_t&");
  }
  virtual ~transfer_details() {
    TRACE_DTOR(transfer_details);
    handler.reset();
  }

  virtual void operator()(post_t& post);

  virtual void clear() {
    expr.mark_uncompiled();
    temps.clear();

    item_handler<post_t>::clear();
  }
};

class day_of_week_posts : public subtotal_posts
{
  posts_list days_of_the_week[7];

  day_of_week_posts();

public:
  day_of_week_posts(post_handler_ptr handler, expr_t& amount_expr)
    : subtotal_posts(handler, amount_expr) {
    TRACE_CTOR(day_of_week_posts, "post_handler_ptr, bool");
  }
  virtual ~day_of_week_posts() throw() {
    TRACE_DTOR(day_of_week_posts);
  }

  virtual void flush();
  virtual void operator()(post_t& post) {
    days_of_the_week[post.date().day_of_week()].push_back(&post);
  }

  virtual void clear() {
    for (int i = 0; i < 7; i++)
      days_of_the_week[i].clear();

    subtotal_posts::clear();
  }
};

class generate_posts : public item_handler<post_t>
{
  generate_posts();

protected:
  typedef std::pair<date_interval_t, post_t *> pending_posts_pair;
  typedef std::list<pending_posts_pair>        pending_posts_list;

  pending_posts_list pending_posts;
  temporaries_t      temps;

public:
  generate_posts(post_handler_ptr handler)
    : item_handler<post_t>(handler) {
    TRACE_CTOR(generate_posts, "post_handler_ptr");
  }

  virtual ~generate_posts() {
    TRACE_DTOR(generate_posts);
    handler.reset();
  }

  void add_period_xacts(period_xacts_list& period_xacts);

  virtual void add_post(const date_interval_t& period, post_t& post);

  virtual void clear() {
    pending_posts.clear();
    temps.clear();

    item_handler<post_t>::clear();
  }
};

class budget_posts : public generate_posts
{
#define BUDGET_NO_BUDGET   0x00
#define BUDGET_BUDGETED    0x01
#define BUDGET_UNBUDGETED  0x02
#define BUDGET_WRAP_VALUES 0x04

  uint_least8_t flags;
  date_t        terminus;

  budget_posts();

public:
  budget_posts(post_handler_ptr handler,
               date_t           _terminus,
               uint_least8_t    _flags = BUDGET_BUDGETED)
    : generate_posts(handler), flags(_flags), terminus(_terminus) {
    TRACE_CTOR(budget_posts, "post_handler_ptr, date_t, uint_least8_t");
  }
  virtual ~budget_posts() throw() {
    TRACE_DTOR(budget_posts);
  }

  void report_budget_items(const date_t& date);

  virtual void flush();
  virtual void operator()(post_t& post);
};

class forecast_posts : public generate_posts
{
  predicate_t       pred;
  scope_t&          context;
  const std::size_t forecast_years;

 public:
  forecast_posts(post_handler_ptr   handler,
                 const predicate_t& predicate,
                 scope_t&           _context,
                 const std::size_t  _forecast_years)
    : generate_posts(handler), pred(predicate), context(_context),
      forecast_years(_forecast_years) {
    TRACE_CTOR(forecast_posts,
               "post_handler_ptr, predicate_t, scope_t&, std::size_t");
  }
  virtual ~forecast_posts() throw() {
    TRACE_DTOR(forecast_posts);
  }

  virtual void add_post(const date_interval_t& period, post_t& post);
  virtual void flush();

  virtual void clear() {
    pred.mark_uncompiled();
    generate_posts::clear();
  }
};

class inject_posts : public item_handler<post_t>
{
  typedef std::set<xact_t *>                       tag_injected_set;
  typedef std::pair<account_t *, tag_injected_set> tag_mapping_pair;
  typedef std::pair<string, tag_mapping_pair>      tags_list_pair;

  std::list<tags_list_pair> tags_list;
  temporaries_t             temps;

 public:
  inject_posts(post_handler_ptr handler, const string& tag_list,
               account_t * master);

  virtual ~inject_posts() throw() {
    TRACE_DTOR(inject_posts);
    handler.reset();
  }

  virtual void operator()(post_t& post);
};

//////////////////////////////////////////////////////////////////////
//
// Account filters
//

template <typename Iterator>
class pass_down_accounts : public item_handler<account_t>
{
  pass_down_accounts();

  optional<predicate_t> pred;
  optional<scope_t&>    context;

public:
  pass_down_accounts(acct_handler_ptr             handler,
                     Iterator&                    iter,
                     const optional<predicate_t>& _pred    = none,
                     const optional<scope_t&>&    _context = none)
    : item_handler<account_t>(handler), pred(_pred), context(_context) {
    TRACE_CTOR(pass_down_accounts, "acct_handler_ptr, accounts_iterator, ...");

    while (account_t * account = *iter++) {
      if (! pred) {
        item_handler<account_t>::operator()(*account);
      } else {
        bind_scope_t bound_scope(*context, *account);
        if ((*pred)(bound_scope))
          item_handler<account_t>::operator()(*account);
      }
    }

    item_handler<account_t>::flush();
  }

  virtual ~pass_down_accounts() {
    TRACE_DTOR(pass_down_accounts);
  }

  virtual void clear() {
    if (pred)
      pred->mark_uncompiled();

    item_handler<account_t>::clear();
  }
};

} // namespace ledger