/*
 * Copyright (c) 2007-2009, Novell Inc.
 *
 * This program is licensed under the BSD license, read LICENSE.BSD
 * for further information
 */

/*
 * transaction.c
 *
 * Transaction handling
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <assert.h>

#include "transaction.h"
#include "solver.h"
#include "bitmap.h"
#include "pool.h"
#include "poolarch.h"
#include "evr.h"
#include "util.h"

static int
obsq_sortcmp(const void *ap, const void *bp, void *dp)
{
  Id a, b, oa, ob;
  Pool *pool = dp;
  Solvable *s, *oas, *obs;
  int r;

  a = ((Id *)ap)[0];
  oa = ((Id *)ap)[1];
  b = ((Id *)bp)[0];
  ob = ((Id *)bp)[1];
  if (a != b)
    return a - b;
  if (oa == ob)
    return 0;
  s = pool->solvables + a;
  oas = pool->solvables + oa;
  obs = pool->solvables + ob;
  if (oas->name != obs->name)
    {
      if (oas->name == s->name)
        return -1;
      if (obs->name == s->name)
        return 1;
      return strcmp(id2str(pool, oas->name), id2str(pool, obs->name));
    }
  r = evrcmp(pool, oas->evr, obs->evr, EVRCMP_COMPARE);
  if (r)
    return -r;	/* highest version first */
  return oa - ob;
}

void
transaction_all_obs_pkgs(Transaction *trans, Id p, Queue *pkgs)
{
  Pool *pool = trans->pool;
  Solvable *s = pool->solvables + p;
  Queue *ti = &trans->transaction_info;
  Id q;
  int i;

  queue_empty(pkgs);
  if (p <= 0 || !s->repo)
    return;
  if (s->repo == pool->installed)
    {
      q = trans->transaction_installed[p - pool->installed->start];
      if (!q)
	return;
      if (q > 0)
	{
	  queue_push(pkgs, q);
	  return;
	}
      /* find which packages obsolete us */
      for (i = 0; i < ti->count; i += 2)
	if (ti->elements[i + 1] == p)
	  {
	    queue_push(pkgs, p);
	    queue_push(pkgs, ti->elements[i]);
	  }
      /* sort obsoleters */
      if (pkgs->count > 2)
	sat_sort(pkgs->elements, pkgs->count / 2, 2 * sizeof(Id), obsq_sortcmp, pool);
      for (i = 0; i < pkgs->count; i += 2)
	pkgs->elements[i / 2] = pkgs->elements[i + 1];
      pkgs->count /= 2;
    }
  else
    {
      /* find the packages we obsolete */
      for (i = 0; i < ti->count; i += 2)
	{
	  if (ti->elements[i] == p)
	    queue_push(pkgs, ti->elements[i + 1]);
	  else if (pkgs->count)
	    break;
	}
    }
}

Id
transaction_obs_pkg(Transaction *trans, Id p)
{
  Pool *pool = trans->pool;
  Solvable *s = pool->solvables + p;
  Queue ti;
  Id tibuf[5];

  if (p <= 0 || !s->repo)
    return 0;
  if (s->repo == pool->installed)
    {
      p = trans->transaction_installed[p - pool->installed->start];
      return p < 0 ? -p : p;
    }
  queue_init_buffer(&ti, tibuf, sizeof(tibuf)/sizeof(*tibuf));
  transaction_all_obs_pkgs(trans, p, &ti);
  p = ti.count ? ti.elements[0] : 0;
  queue_free(&ti);
  return p;
}


/*
 * calculate base type of transaction element
 */

static Id
transaction_base_type(Transaction *trans, Id p)
{
  Pool *pool = trans->pool;
  Solvable *s, *s2;
  int r;
  Id p2;

  if (!MAPTST(&trans->transactsmap, p))
    return SOLVER_TRANSACTION_IGNORE;
  p2 = transaction_obs_pkg(trans, p);
  if (pool->installed && pool->solvables[p].repo == pool->installed)
    {
      /* erase */
      if (!p2)
	return SOLVER_TRANSACTION_ERASE;
      s = pool->solvables + p;
      s2 = pool->solvables + p2;
      if (s->name == s2->name)
	{
	  if (s->evr == s2->evr && solvable_identical(s, s2))
	    return SOLVER_TRANSACTION_REINSTALLED;
	  r = evrcmp(pool, s->evr, s2->evr, EVRCMP_COMPARE);
	  if (r < 0)
	    return SOLVER_TRANSACTION_UPGRADED;
	  else if (r > 0)
	    return SOLVER_TRANSACTION_DOWNGRADED;
	  return SOLVER_TRANSACTION_CHANGED;
	}
      return SOLVER_TRANSACTION_OBSOLETED;
    }
  else
    {
      int noobs = trans->noobsmap.size && MAPTST(&trans->noobsmap, p);
      if (noobs)
	return p2 ? SOLVER_TRANSACTION_MULTIREINSTALL : SOLVER_TRANSACTION_MULTIINSTALL;
      if (!p2)
	return SOLVER_TRANSACTION_INSTALL;
      s = pool->solvables + p;
      s2 = pool->solvables + p2;
      if (s->name == s2->name)
	{
	  if (s->evr == s2->evr && solvable_identical(s, s2))
	    return SOLVER_TRANSACTION_REINSTALL;
	  r = evrcmp(pool, s->evr, s2->evr, EVRCMP_COMPARE);
	  if (r > 0)
	    return SOLVER_TRANSACTION_UPGRADE;
	  else if (r < 0)
	    return SOLVER_TRANSACTION_DOWNGRADE;
	  else
	    return SOLVER_TRANSACTION_CHANGE;
	}
      return SOLVER_TRANSACTION_OBSOLETES;
    }
}

/*
 * return type of transaction element
 *
 * filtering is needed if either not all packages are shown
 * or replaces are not shown, as otherwise parts of the
 * transaction might not be shown to the user */

Id
transaction_type(Transaction *trans, Id p, int mode)
{
  Pool *pool = trans->pool;
  Solvable *s = pool->solvables + p;
  Queue oq, rq;
  Id type, q;
  int i, j, ref = 0;
  const char *n;

  if (!s->repo)
    return SOLVER_TRANSACTION_IGNORE;

  n = id2str(pool, s->name);
  if (!strncmp(n, "patch:", 6))
    return SOLVER_TRANSACTION_IGNORE;
  if (!strncmp(n, "pattern:", 8))
    return SOLVER_TRANSACTION_IGNORE;

  type = transaction_base_type(trans, p);

  if (type == SOLVER_TRANSACTION_IGNORE)
    return SOLVER_TRANSACTION_IGNORE;	/* not part of the transaction */

  if ((mode & SOLVER_TRANSACTION_RPM_ONLY) != 0)
    {
      /* application wants to know what to feed to rpm */
      if (type == SOLVER_TRANSACTION_ERASE || type == SOLVER_TRANSACTION_INSTALL || type == SOLVER_TRANSACTION_MULTIINSTALL)
	return type;
      if (s->repo == pool->installed)
	return SOLVER_TRANSACTION_IGNORE;	/* ignore as we're being obsoleted */
      if (type == SOLVER_TRANSACTION_MULTIREINSTALL)
	return SOLVER_TRANSACTION_MULTIINSTALL;
      return SOLVER_TRANSACTION_INSTALL;
    }

  if ((mode & SOLVER_TRANSACTION_SHOW_MULTIINSTALL) == 0)
    {
      /* application wants to make no difference between install
       * and multiinstall */
      if (type == SOLVER_TRANSACTION_MULTIINSTALL)
        type = SOLVER_TRANSACTION_INSTALL;
      if (type == SOLVER_TRANSACTION_MULTIREINSTALL)
        type = SOLVER_TRANSACTION_REINSTALL;
    }

  if ((mode & SOLVER_TRANSACTION_CHANGE_IS_REINSTALL))
    {
      /* application wants to make no difference between change
       * and reinstall */
      if (type == SOLVER_TRANSACTION_CHANGED)
	type = SOLVER_TRANSACTION_REINSTALLED;
      else if (type == SOLVER_TRANSACTION_CHANGE)
	type = SOLVER_TRANSACTION_REINSTALL;
    }

  if (type == SOLVER_TRANSACTION_ERASE || type == SOLVER_TRANSACTION_INSTALL || type == SOLVER_TRANSACTION_MULTIINSTALL)
    return type;

  if (s->repo == pool->installed && (mode & SOLVER_TRANSACTION_SHOW_ACTIVE) == 0)
    {
      /* erase element and we're showing the passive side */
      if ((mode & SOLVER_TRANSACTION_SHOW_OBSOLETES) == 0 && type == SOLVER_TRANSACTION_OBSOLETED)
	type = SOLVER_TRANSACTION_ERASE;
      return type;
    }
  if (s->repo != pool->installed && (mode & SOLVER_TRANSACTION_SHOW_ACTIVE) != 0)
    {
      /* install element and we're showing the active side */
      if ((mode & SOLVER_TRANSACTION_SHOW_OBSOLETES) == 0 && type == SOLVER_TRANSACTION_OBSOLETES)
	type = SOLVER_TRANSACTION_INSTALL;
      return type;
    }

  /* the element doesn't match the show mode */

  /* if we're showing all references, we can ignore this package */
  if ((mode & (SOLVER_TRANSACTION_SHOW_ALL|SOLVER_TRANSACTION_SHOW_OBSOLETES)) == (SOLVER_TRANSACTION_SHOW_ALL|SOLVER_TRANSACTION_SHOW_OBSOLETES))
    return SOLVER_TRANSACTION_IGNORE;

  /* we're not showing all refs. check if some other package
   * references us. If yes, it's safe to ignore this package,
   * otherwise we need to map the type */

  /* most of the time there's only one reference, so check it first */
  q = transaction_obs_pkg(trans, p);

  if ((mode & SOLVER_TRANSACTION_SHOW_OBSOLETES) == 0)
    {
      Solvable *sq = pool->solvables + q;
      if (sq->name != s->name)
	{
	  /* it's a replace but we're not showing replaces. map type. */
	  if (s->repo == pool->installed)
	    return SOLVER_TRANSACTION_ERASE;
	  else if (type == SOLVER_TRANSACTION_MULTIREINSTALL)
	    return SOLVER_TRANSACTION_MULTIINSTALL;
	  else
	    return SOLVER_TRANSACTION_INSTALL;
	}
    }
  
  /* if there's a match, p will be shown when q
   * is processed */
  if (transaction_obs_pkg(trans, q) == p)
    return SOLVER_TRANSACTION_IGNORE;

  /* too bad, a miss. check em all */
  queue_init(&oq);
  queue_init(&rq);
  transaction_all_obs_pkgs(trans, p, &oq);
  for (i = 0; i < oq.count; i++)
    {
      q = oq.elements[i];
      if ((mode & SOLVER_TRANSACTION_SHOW_OBSOLETES) == 0)
	{
	  Solvable *sq = pool->solvables + q;
	  if (sq->name != s->name)
	    continue;
	}
      /* check if we are referenced? */
      if ((mode & SOLVER_TRANSACTION_SHOW_ALL) != 0)
	{
	  transaction_all_obs_pkgs(trans, q, &rq);
	  for (j = 0; j < rq.count; j++)
	    if (rq.elements[j] == p)
	      {
	        ref = 1;
	        break;
	      }
	  if (ref)
	    break;
	}
      else if (transaction_obs_pkg(trans, q) == p)
        {
	  ref = 1;
	  break;
        }
    }
  queue_free(&oq);
  queue_free(&rq);

  if (!ref)
    {
      /* we're not referenced. map type */
      if (s->repo == pool->installed)
	return SOLVER_TRANSACTION_ERASE;
      else if (type == SOLVER_TRANSACTION_MULTIREINSTALL)
	return SOLVER_TRANSACTION_MULTIINSTALL;
      else
	return SOLVER_TRANSACTION_INSTALL;
    }
  /* there was a ref, so p is shown with some other package */
  return SOLVER_TRANSACTION_IGNORE;
}



static int
classify_cmp(const void *ap, const void *bp, void *dp)
{
  Transaction *trans = dp;
  Pool *pool = trans->pool;
  const Id *a = ap;
  const Id *b = bp;
  int r;

  r = a[0] - b[0];
  if (r)
    return r;
  r = a[2] - b[2];
  if (r)
    return a[2] && b[2] ? strcmp(id2str(pool, a[2]), id2str(pool, b[2])) : r;
  r = a[3] - b[3];
  if (r)
    return a[3] && b[3] ? strcmp(id2str(pool, a[3]), id2str(pool, b[3])) : r;
  return 0;
}

static int
classify_cmp_pkgs(const void *ap, const void *bp, void *dp)
{
  Transaction *trans = dp;
  Pool *pool = trans->pool;
  Id a = *(Id *)ap;
  Id b = *(Id *)bp;
  Solvable *sa, *sb;

  sa = pool->solvables + a;
  sb = pool->solvables + b;
  if (sa->name != sb->name)
    return strcmp(id2str(pool, sa->name), id2str(pool, sb->name));
  if (sa->evr != sb->evr)
    {
      int r = evrcmp(pool, sa->evr, sb->evr, EVRCMP_COMPARE);
      if (r)
	return r;
    }
  return a - b;
}

void
transaction_classify(Transaction *trans, int mode, Queue *classes)
{
  Pool *pool = trans->pool;
  int ntypes[SOLVER_TRANSACTION_MAXTYPE + 1];
  Solvable *s, *sq;
  Id v, vq, type, p, q;
  int i, j;

  queue_empty(classes);
  memset(ntypes, 0, sizeof(ntypes));
  /* go through transaction and classify each step */
  for (i = 0; i < trans->steps.count; i++)
    {
      p = trans->steps.elements[i];
      s = pool->solvables + p;
      type = transaction_type(trans, p, mode);
      ntypes[type]++;
      if (!pool->installed || s->repo != pool->installed)
	continue;
      /* look at arch/vendor changes */
      q = transaction_obs_pkg(trans, p);
      if (!q)
	continue;
      sq = pool->solvables + q;

      v = s->arch;
      vq = sq->arch;
      if (v != vq)
	{
	  if ((mode & SOLVER_TRANSACTION_MERGE_ARCHCHANGES) != 0)
	    v = vq = 0;
	  for (j = 0; j < classes->count; j += 4)
	    if (classes->elements[j] == SOLVER_TRANSACTION_ARCHCHANGE && classes->elements[j + 2] == v && classes->elements[j + 3] == vq)
	      break;
	  if (j == classes->count)
	    {
	      queue_push(classes, SOLVER_TRANSACTION_ARCHCHANGE);
	      queue_push(classes, 1);
	      queue_push(classes, v);
	      queue_push(classes, vq);
	    }
	  else
	    classes->elements[j + 1]++;
	}

      v = s->vendor ? s->vendor : 1;
      vq = sq->vendor ? sq->vendor : 1;
      if (v != vq)
	{
	  if ((mode & SOLVER_TRANSACTION_MERGE_VENDORCHANGES) != 0)
	    v = vq = 0;
	  for (j = 0; j < classes->count; j += 4)
	    if (classes->elements[j] == SOLVER_TRANSACTION_VENDORCHANGE && classes->elements[j + 2] == v && classes->elements[j + 3] == vq)
	      break;
	  if (j == classes->count)
	    {
	      queue_push(classes, SOLVER_TRANSACTION_VENDORCHANGE);
	      queue_push(classes, 1);
	      queue_push(classes, v);
	      queue_push(classes, vq);
	    }
	  else
	    classes->elements[j + 1]++;
	}
    }
  /* now sort all vendor/arch changes */
  if (classes->count > 4)
    sat_sort(classes->elements, classes->count / 4, 4 * sizeof(Id), classify_cmp, trans);
  /* finally add all classes. put erases last */
  i = SOLVER_TRANSACTION_ERASE;
  if (ntypes[i])
    {
      queue_unshift(classes, 0);
      queue_unshift(classes, 0);
      queue_unshift(classes, ntypes[i]);
      queue_unshift(classes, i);
    }
  for (i = SOLVER_TRANSACTION_MAXTYPE; i > 0; i--)
    {
      if (!ntypes[i])
	continue;
      if (i == SOLVER_TRANSACTION_ERASE)
	continue;
      queue_unshift(classes, 0);
      queue_unshift(classes, 0);
      queue_unshift(classes, ntypes[i]);
      queue_unshift(classes, i);
    }
}

void
transaction_classify_pkgs(Transaction *trans, int mode, Id class, Id from, Id to, Queue *pkgs)
{
  Pool *pool = trans->pool;
  int i;
  Id type, p, q;
  Solvable *s, *sq;

  queue_empty(pkgs);
  for (i = 0; i < trans->steps.count; i++)
    {
      p = trans->steps.elements[i];
      s = pool->solvables + p;
      if (class <= SOLVER_TRANSACTION_MAXTYPE)
	{
	  type = transaction_type(trans, p, mode);
	  if (type == class)
	    queue_push(pkgs, p);
	  continue;
	}
      if (!pool->installed || s->repo != pool->installed)
	continue;
      q = transaction_obs_pkg(trans, p);
      if (!q)
	continue;
      sq = pool->solvables + q;
      if (class == SOLVER_TRANSACTION_ARCHCHANGE)
	{
	  if ((!from && !to) || (s->arch == from && sq->arch == to))
	    queue_push(pkgs, p);
	  continue;
	}
      if (class == SOLVER_TRANSACTION_VENDORCHANGE)
	{
	  Id v = s->vendor ? s->vendor : 1;
	  Id vq = sq->vendor ? sq->vendor : 1;
	  if ((!from && !to) || (v == from && vq == to))
	    queue_push(pkgs, p);
	  continue;
	}
    }
  if (pkgs->count > 1)
    sat_sort(pkgs->elements, pkgs->count, sizeof(Id), classify_cmp_pkgs, trans);
}

static void
create_transaction_info(Transaction *trans, Queue *decisionq)
{
  Pool *pool = trans->pool;
  Queue *ti = &trans->transaction_info;
  Repo *installed = pool->installed;
  int i, j, noobs;
  Id p, p2, pp2;
  Solvable *s, *s2;

  queue_empty(ti);
  trans->transaction_installed = sat_free(trans->transaction_installed);
  if (!installed)
    return;	/* no info needed */
  for (i = 0; i < decisionq->count; i++)
    {
      p = decisionq->elements[i];
      if (p <= 0 || p == SYSTEMSOLVABLE)
	continue;
      s = pool->solvables + p;
      if (!s->repo || s->repo == installed)
	continue;
      noobs = trans->noobsmap.size && MAPTST(&trans->noobsmap, p);
      FOR_PROVIDES(p2, pp2, s->name)
	{
	  if (!MAPTST(&trans->transactsmap, p2))
	    continue;
	  s2 = pool->solvables + p2;
	  if (s2->repo != installed)
	    continue;
	  if (noobs && (s->name != s2->name || s->evr != s2->evr || s->arch != s2->arch))
	    continue;
	  if (!pool->implicitobsoleteusesprovides && s->name != s2->name)
	    continue;
	  if (pool->obsoleteusescolors && !pool_colormatch(pool, s, s2))
	    continue;
	  queue_push(ti, p);
	  queue_push(ti, p2);
	}
      if (s->obsoletes && !noobs)
	{
	  Id obs, *obsp = s->repo->idarraydata + s->obsoletes;
	  while ((obs = *obsp++) != 0)
	    {
	      FOR_PROVIDES(p2, pp2, obs)
		{
		  s2 = pool->solvables + p2;
		  if (s2->repo != installed)
		    continue;
		  if (!pool->obsoleteusesprovides && !pool_match_nevr(pool, pool->solvables + p2, obs))
		    continue;
		  if (pool->obsoleteusescolors && !pool_colormatch(pool, s, s2))
		    continue;
		  queue_push(ti, p);
		  queue_push(ti, p2);
		}
	    }
	}
    }
  sat_sort(ti->elements, ti->count / 2, 2 * sizeof(Id), obsq_sortcmp, pool);
  /* now unify */
  for (i = j = 0; i < ti->count; i += 2)
    {
      if (j && ti->elements[i] == ti->elements[j - 2] && ti->elements[i + 1] == ti->elements[j - 1])
	continue;
      ti->elements[j++] = ti->elements[i];
      ti->elements[j++] = ti->elements[i + 1];
    }
  ti->count = j;

  /* create transaction_installed helper */
  trans->transaction_installed = sat_calloc(installed->end - installed->start, sizeof(Id));
  for (i = 0; i < ti->count; i += 2)
    {
      j = ti->elements[i + 1] - installed->start;
      if (!trans->transaction_installed[j])
	trans->transaction_installed[j] = ti->elements[i];
      else
	{
	  /* more than one package obsoletes us. compare */
	  Id q[4];
	  if (trans->transaction_installed[j] > 0)
	    trans->transaction_installed[j] = -trans->transaction_installed[j];
	  q[0] = q[2] = ti->elements[i + 1];
	  q[1] = ti->elements[i];
	  q[3] = -trans->transaction_installed[j];
	  if (obsq_sortcmp(q, q + 2, pool) < 0)
	    trans->transaction_installed[j] = -ti->elements[i];
	}
    }
}


void
transaction_calculate(Transaction *trans, Queue *decisionq, Map *noobsmap)
{
  Pool *pool = trans->pool;
  Repo *installed = pool->installed;
  int i, neednoobs;
  Id p;
  Solvable *s;

  if (noobsmap && !noobsmap->size)
    noobsmap = 0;	/* ignore empty map */
  queue_empty(&trans->steps);
  map_init(&trans->transactsmap, pool->nsolvables);
  neednoobs = 0;
  for (i = 0; i < decisionq->count; i++)
    {
      p = decisionq->elements[i];
      s = pool->solvables + (p > 0 ? p : -p);
      if (!s->repo)
	continue;
      if (installed && s->repo == installed && p < 0)
	MAPSET(&trans->transactsmap, -p);
      if ((!installed || s->repo != installed) && p > 0)
	{
#if 0
	  const char *n = id2str(pool, s->name);
	  if (!strncmp(n, "patch:", 6))
	    continue;
	  if (!strncmp(n, "pattern:", 8))
	    continue;
#endif
	  MAPSET(&trans->transactsmap, p);
	  if (noobsmap && MAPTST(noobsmap, p))
	    neednoobs = 1;
	}
    }
  MAPCLR(&trans->transactsmap, SYSTEMSOLVABLE);
  if (neednoobs)
    map_init_clone(&trans->noobsmap, noobsmap);

  create_transaction_info(trans, decisionq);

  if (installed)
    {
      FOR_REPO_SOLVABLES(installed, p, s)
	{
	  if (MAPTST(&trans->transactsmap, p))
	    queue_push(&trans->steps, p);
	}
    }
  for (i = 0; i < decisionq->count; i++)
    {
      p = decisionq->elements[i];
      if (p > 0 && MAPTST(&trans->transactsmap, p))
        queue_push(&trans->steps, p);
    }
}

int
transaction_installedresult(Transaction *trans, Queue *installedq)
{
  Pool *pool = trans->pool;
  Repo *installed = pool->installed;
  Solvable *s;
  int i, cutoff;
  Id p;

  queue_empty(installedq);
  /* first the new installs, than the kept packages */
  for (i = 0; i < trans->steps.count; i++)
    {
      p = trans->steps.elements[i];
      s = pool->solvables + p;
      if (installed && s->repo == installed)
	continue;
      queue_push(installedq, p);
    }
  cutoff = installedq->count;
  if (installed)
    {
      FOR_REPO_SOLVABLES(installed, p, s)
	if (!MAPTST(&trans->transactsmap, p))
          queue_push(installedq, p);
    }
  return cutoff;
}

static void
transaction_create_installedmap(Transaction *trans, Map *installedmap)
{
  Pool *pool = trans->pool;
  Repo *installed = pool->installed;
  Solvable *s;
  Id p;
  int i;

  map_init(installedmap, pool->nsolvables);
  for (i = 0; i < trans->steps.count; i++)
    {
      p = trans->steps.elements[i];
      s = pool->solvables + p;
      if (!installed || s->repo != installed)
        MAPSET(installedmap, p);
    }
  if (installed)
    {
      FOR_REPO_SOLVABLES(installed, p, s)
	if (!MAPTST(&trans->transactsmap, p))
          MAPSET(installedmap, p);
    }
}

int
transaction_calc_installsizechange(Transaction *trans)
{
  Map installedmap;
  int change;

  transaction_create_installedmap(trans, &installedmap);
  change = pool_calc_installsizechange(trans->pool, &installedmap);
  map_free(&installedmap);
  return change;
}

void
transaction_calc_duchanges(Transaction *trans, DUChanges *mps, int nmps)
{
  Map installedmap;

  transaction_create_installedmap(trans, &installedmap);
  pool_calc_duchanges(trans->pool, &installedmap, mps, nmps);
  map_free(&installedmap);
}

struct _TransactionElement {
  Id p;		/* solvable id */
  Id edges;	/* pointer into edges data */
  Id mark;
};

struct _TransactionOrderdata {
  struct _TransactionElement *tes;
  int ntes;
  Id *invedgedata;
  int ninvedgedata;
};

#define TYPE_BROKEN	(1<<0)
#define TYPE_CON    	(1<<1)

#define TYPE_REQ_P    	(1<<2)
#define TYPE_PREREQ_P 	(1<<3)

#define TYPE_REQ    	(1<<4)
#define TYPE_PREREQ 	(1<<5)

#define TYPE_CYCLETAIL  (1<<16)
#define TYPE_CYCLEHEAD  (1<<17)

#define EDGEDATA_BLOCK	127

void
transaction_init(Transaction *trans, Pool *pool)
{
  memset(trans, 0, sizeof(*trans));
  trans->pool = pool;
}

void
transaction_init_clone(Transaction *trans, Transaction *srctrans)
{
  memset(trans, 0, sizeof(*trans));
  trans->pool = srctrans->pool;
  queue_init_clone(&trans->steps, &srctrans->steps);
  queue_init_clone(&trans->transaction_info, &srctrans->transaction_info);
  if (srctrans->transaction_installed)
    {
      Repo *installed = srctrans->pool->installed;
      trans->transaction_installed = sat_calloc(installed->end - installed->start, sizeof(Id));
      memcpy(trans->transaction_installed, srctrans->transaction_installed, (installed->end - installed->start) * sizeof(Id));
    }
  map_init_clone(&trans->transactsmap, &srctrans->transactsmap);
  map_init_clone(&trans->noobsmap, &srctrans->noobsmap);
  if (srctrans->orderdata)
    {
      struct _TransactionOrderdata *od = srctrans->orderdata;
      trans->orderdata = sat_calloc(1, sizeof(*trans->orderdata));
      trans->orderdata->tes = sat_malloc2(od->ntes, sizeof(*od->tes));
      memcpy(trans->orderdata->tes, od->tes, od->ntes * sizeof(*od->tes));
      trans->orderdata->ntes = od->ntes;
      trans->orderdata->invedgedata = sat_malloc2(od->ninvedgedata, sizeof(Id));
      memcpy(trans->orderdata->invedgedata, od->invedgedata, od->ninvedgedata * sizeof(Id));
      trans->orderdata->ninvedgedata = od->ninvedgedata;
    }
}

void
transaction_free(Transaction *trans)
{
  queue_free(&trans->steps);
  queue_free(&trans->transaction_info);
  trans->transaction_installed = sat_free(trans->transaction_installed);
  map_free(&trans->transactsmap);
  map_free(&trans->noobsmap);
  transaction_free_orderdata(trans);
}

void
transaction_free_orderdata(Transaction *trans)
{
  if (trans->orderdata)
    {
      struct _TransactionOrderdata *od = trans->orderdata;
      od->tes = sat_free(od->tes);
      od->invedgedata = sat_free(od->invedgedata);
      trans->orderdata = sat_free(trans->orderdata);
    }
}

struct orderdata {
  Transaction *trans;
  struct _TransactionElement *tes;
  int ntes;
  Id *edgedata;
  int nedgedata;
  Id *invedgedata;

  Queue cycles;
  Queue cyclesdata;
  int ncycles;
};

static int
addteedge(struct orderdata *od, int from, int to, int type)
{
  int i;
  struct _TransactionElement *te;

  if (from == to)
    return 0;

  /* printf("edge %d(%s) -> %d(%s) type %x\n", from, solvid2str(pool, od->tes[from].p), to, solvid2str(pool, od->tes[to].p), type); */

  te = od->tes + from;
  for (i = te->edges; od->edgedata[i]; i += 2)
    if (od->edgedata[i] == to)
      break;
  /* test of brokenness */
  if (type == TYPE_BROKEN)
    return od->edgedata[i] && (od->edgedata[i + 1] & TYPE_BROKEN) != 0 ? 1 : 0;
  if (od->edgedata[i])
    {
      od->edgedata[i + 1] |= type;
      return 0;
    }
  if (i + 1 == od->nedgedata)
    {
      /* printf("tail add %d\n", i - te->edges); */
      if (!i)
	te->edges = ++i;
      od->edgedata = sat_extend(od->edgedata, od->nedgedata, 3, sizeof(Id), EDGEDATA_BLOCK);
    }
  else
    {
      /* printf("extend %d\n", i - te->edges); */
      od->edgedata = sat_extend(od->edgedata, od->nedgedata, 3 + (i - te->edges), sizeof(Id), EDGEDATA_BLOCK);
      if (i > te->edges)
	memcpy(od->edgedata + od->nedgedata, od->edgedata + te->edges, sizeof(Id) * (i - te->edges));
      i = od->nedgedata + (i - te->edges);
      te->edges = od->nedgedata;
    }
  od->edgedata[i] = to;
  od->edgedata[i + 1] = type;
  od->edgedata[i + 2] = 0;	/* end marker */
  od->nedgedata = i + 3;
  return 0;
}

static int
addedge(struct orderdata *od, Id from, Id to, int type)
{
  Transaction *trans = od->trans;
  Pool *pool = trans->pool;
  Solvable *s;
  struct _TransactionElement *te;
  int i;

  // printf("addedge %d %d type %d\n", from, to, type);
  s = pool->solvables + from;
  if (s->repo == pool->installed && trans->transaction_installed[from - pool->installed->start])
    {
      /* obsolete, map to install */
      if (trans->transaction_installed[from - pool->installed->start] > 0)
	from = trans->transaction_installed[from - pool->installed->start];
      else
	{
	  int ret = 0;
	  Queue ti;
	  Id tibuf[5];

	  queue_init_buffer(&ti, tibuf, sizeof(tibuf)/sizeof(*tibuf));
	  transaction_all_obs_pkgs(trans, from, &ti);
	  for (i = 0; i < ti.count; i++)
	    ret |= addedge(od, ti.elements[i], to, type);
	  queue_free(&ti);
	  return ret;
	}
    }
  s = pool->solvables + to;
  if (s->repo == pool->installed && trans->transaction_installed[to - pool->installed->start])
    {
      /* obsolete, map to install */
      if (trans->transaction_installed[to - pool->installed->start] > 0)
	to = trans->transaction_installed[to - pool->installed->start];
      else
	{
	  int ret = 0;
	  Queue ti;
	  Id tibuf[5];

	  queue_init_buffer(&ti, tibuf, sizeof(tibuf)/sizeof(*tibuf));
	  transaction_all_obs_pkgs(trans, to, &ti);
	  for (i = 0; i < ti.count; i++)
	    ret |= addedge(od, from, ti.elements[i], type);
	  queue_free(&ti);
	  return ret;
	}
    }

  /* map from/to to te numbers */
  for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
    if (te->p == to)
      break;
  if (i == od->ntes)
    return 0;
  to = i;

  for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
    if (te->p == from)
      break;
  if (i == od->ntes)
    return 0;

  return addteedge(od, i, to, type);
}

#if 1
static int
havechoice(struct orderdata *od, Id p, Id q1, Id q2)
{
  Transaction *trans = od->trans;
  Pool *pool = trans->pool;
  Id ti1buf[5], ti2buf[5];
  Queue ti1, ti2;
  int i, j;

  /* both q1 and q2 are uninstalls. check if their TEs intersect */
  /* common case: just one TE for both packages */
#if 0
  printf("havechoice %d %d %d\n", p, q1, q2);
#endif
  if (trans->transaction_installed[q1 - pool->installed->start] == 0)
    return 1;
  if (trans->transaction_installed[q2 - pool->installed->start] == 0)
    return 1;
  if (trans->transaction_installed[q1 - pool->installed->start] == trans->transaction_installed[q2 - pool->installed->start])
    return 0;
  if (trans->transaction_installed[q1 - pool->installed->start] > 0 && trans->transaction_installed[q2 - pool->installed->start] > 0)
    return 1;
  queue_init_buffer(&ti1, ti1buf, sizeof(ti1buf)/sizeof(*ti1buf));
  transaction_all_obs_pkgs(trans, q1, &ti1);
  queue_init_buffer(&ti2, ti2buf, sizeof(ti2buf)/sizeof(*ti2buf));
  transaction_all_obs_pkgs(trans, q2, &ti2);
  for (i = 0; i < ti1.count; i++)
    for (j = 0; j < ti2.count; j++)
      if (ti1.elements[i] == ti2.elements[j])
	{
	  /* found a common edge */
	  queue_free(&ti1);
	  queue_free(&ti2);
	  return 0;
	}
  queue_free(&ti1);
  queue_free(&ti2);
  return 1;
}
#endif

static inline int
havescripts(Pool *pool, Id solvid)
{
  Solvable *s = pool->solvables + solvid;
  const char *dep;
  if (s->requires)
    {
      Id req, *reqp;
      int inpre = 0;
      reqp = s->repo->idarraydata + s->requires;
      while ((req = *reqp++) != 0)
	{
          if (req == SOLVABLE_PREREQMARKER)
	    {
	      inpre = 1;
	      continue;
	    }
	  if (!inpre)
	    continue;
	  dep = id2str(pool, req);
	  if (*dep == '/' && strcmp(dep, "/sbin/ldconfig") != 0)
	    return 1;
	}
    }
  return 0;
}

static void
addsolvableedges(struct orderdata *od, Solvable *s)
{
  Transaction *trans = od->trans;
  Pool *pool = trans->pool;
  Id req, *reqp, con, *conp;
  Id p, p2, pp2;
  int i, j, pre, numins;
  Repo *installed = pool->installed;
  Solvable *s2;
  Queue reqq;
  int provbyinst;

#if 0
  printf("addsolvableedges %s\n", solvable2str(pool, s));
#endif
  p = s - pool->solvables;
  queue_init(&reqq);
  if (s->requires)
    {
      reqp = s->repo->idarraydata + s->requires;
      pre = TYPE_REQ;
      while ((req = *reqp++) != 0)
	{
	  if (req == SOLVABLE_PREREQMARKER)
	    {
	      pre = TYPE_PREREQ;
	      continue;
	    }
#if 0
	  if (pre != TYPE_PREREQ && installed && s->repo == installed)
	    {
	      /* ignore normal requires if we're getting obsoleted */
	      if (trans->transaction_installed[p - pool->installed->start])
	        continue;
	    }
#endif
	  queue_empty(&reqq);
	  numins = 0;	/* number of packages to be installed providing it */
	  provbyinst = 0;	/* provided by kept package */
	  FOR_PROVIDES(p2, pp2, req)
	    {
	      s2 = pool->solvables + p2;
	      if (p2 == p)
		{
		  reqq.count = 0;	/* self provides */
		  break;
		}
	      if (s2->repo == installed && !MAPTST(&trans->transactsmap, p2))
		{
		  provbyinst = 1;
#if 0
		  printf("IGNORE inst provides %s by %s\n", dep2str(pool, req), solvable2str(pool, s2));
		  reqq.count = 0;	/* provided by package that stays installed */
		  break;
#else
		  continue;
#endif
		}
	      if (s2->repo != installed && !MAPTST(&trans->transactsmap, p2))
		continue;		/* package stays uninstalled */
	      
	      if (s->repo == installed)
		{
		  /* s gets uninstalled */
		  queue_pushunique(&reqq, p2);
		  if (s2->repo != installed)
		    numins++;
		}
	      else
		{
		  if (s2->repo == installed)
		    continue;	/* s2 gets uninstalled */
		  queue_pushunique(&reqq, p2);
		}
	    }
	  if (provbyinst)
	    {
	      /* prune to harmless ->inst edges */
	      for (i = j = 0; i < reqq.count; i++)
		if (pool->solvables[reqq.elements[i]].repo != installed)
		  reqq.elements[j++] = reqq.elements[i];
	      reqq.count = j;
	    }

	  if (numins && reqq.count)
	    {
	      if (s->repo == installed)
		{
		  for (i = 0; i < reqq.count; i++)
		    {
		      if (pool->solvables[reqq.elements[i]].repo == installed)
			{
			  for (j = 0; j < reqq.count; j++)
			    {
			      if (pool->solvables[reqq.elements[j]].repo != installed)
				{
				  if (trans->transaction_installed[reqq.elements[i] - pool->installed->start] == reqq.elements[j])
				    continue;	/* no self edge */
#if 0
				  printf("add interrreq uninst->inst edge (%s -> %s -> %s)\n", solvid2str(pool, reqq.elements[i]), dep2str(pool, req), solvid2str(pool, reqq.elements[j]));
#endif
				  addedge(od, reqq.elements[i], reqq.elements[j], pre == TYPE_PREREQ ? TYPE_PREREQ_P : TYPE_REQ_P);
				}
			    }
			}
		    }
		}
	      /* no mixed types, remove all deps on uninstalls */
	      for (i = j = 0; i < reqq.count; i++)
		if (pool->solvables[reqq.elements[i]].repo != installed)
		  reqq.elements[j++] = reqq.elements[i];
	      reqq.count = j;
	    }
          if (!reqq.count)
	    continue;
          for (i = 0; i < reqq.count; i++)
	    {
	      int choice = 0;
	      p2 = reqq.elements[i];
	      if (pool->solvables[p2].repo != installed)
		{
		  /* all elements of reqq are installs, thus have different TEs */
		  choice = reqq.count - 1;
		  if (pool->solvables[p].repo != installed)
		    {
#if 0
		      printf("add inst->inst edge choice %d (%s -> %s -> %s)\n", choice, solvid2str(pool, p), dep2str(pool, req), solvid2str(pool, p2));
#endif
		      addedge(od, p, p2, pre);
		    }
		  else
		    {
#if 0
		      printf("add uninst->inst edge choice %d (%s -> %s -> %s)\n", choice, solvid2str(pool, p), dep2str(pool, req), solvid2str(pool, p2));
#endif
		      addedge(od, p, p2, pre == TYPE_PREREQ ? TYPE_PREREQ_P : TYPE_REQ_P);
		    }
		}
	      else
		{
		  if (s->repo != installed)
		    continue;	/* no inst->uninst edges, please! */

		  /* uninst -> uninst edge. Those make trouble. Only add if we must */
		  if (trans->transaction_installed[p - installed->start] && !havescripts(pool, p))
		    {
		      /* p is obsoleted by another package and has no scripts */
		      /* we assume that the obsoletor is good enough to replace p */
		      continue;
		    }
#if 1
		  choice = 0;
		  for (j = 0; j < reqq.count; j++)
		    {
		      if (i == j)
			continue;
		      if (havechoice(od, p, reqq.elements[i], reqq.elements[j]))
			choice++;
		    }
#endif
#if 0
		  printf("add uninst->uninst edge choice %d (%s -> %s -> %s)\n", choice, solvid2str(pool, p), dep2str(pool, req), solvid2str(pool, p2));
#endif
	          addedge(od, p2, p, pre == TYPE_PREREQ ? TYPE_PREREQ_P : TYPE_REQ_P);
		}
	    }
	}
    }
  if (s->conflicts)
    {
      conp = s->repo->idarraydata + s->conflicts;
      while ((con = *conp++) != 0)
	{
	  FOR_PROVIDES(p2, pp2, con)
	    {
	      if (p2 == p)
		continue;
	      s2 = pool->solvables + p2;
	      if (!s2->repo)
		continue;
	      if (s->repo == installed)
		{
		  if (s2->repo != installed && MAPTST(&trans->transactsmap, p2))
		    {
		      /* deinstall p before installing p2 */
#if 0
		      printf("add conflict uninst->inst edge (%s -> %s -> %s)\n", solvid2str(pool, p2), dep2str(pool, con), solvid2str(pool, p));
#endif
		      addedge(od, p2, p, TYPE_CON);
		    }
		}
	      else
		{
		  if (s2->repo == installed && MAPTST(&trans->transactsmap, p2))
		    {
		      /* deinstall p2 before installing p */
#if 0
		      printf("add conflict uninst->inst edge (%s -> %s -> %s)\n", solvid2str(pool, p), dep2str(pool, con), solvid2str(pool, p2));
#endif
		      addedge(od, p, p2, TYPE_CON);
		    }
		}

	    }
	}
    }
  if (s->repo == installed && solvable_lookup_idarray(s, SOLVABLE_TRIGGERS, &reqq) && reqq.count)
    {
      /* we're getting deinstalled/updated. Try to do this before our
       * triggers are hit */
      for (i = 0; i < reqq.count; i++)
	{
	  Id tri = reqq.elements[i];
	  FOR_PROVIDES(p2, pp2, tri)
	    {
	      if (p2 == p)
		continue;
	      s2 = pool->solvables + p2;
	      if (!s2->repo)
		continue;
	      if (s2->name == s->name)
		continue;	/* obsoleted anyway */
	      if (s2->repo != installed && MAPTST(&trans->transactsmap, p2))
		{
		  /* deinstall/update p before installing p2 */
#if 0
		  printf("add trigger uninst->inst edge (%s -> %s -> %s)\n", solvid2str(pool, p2), dep2str(pool, tri), solvid2str(pool, p));
#endif
		  addedge(od, p2, p, TYPE_CON);
		}
	    }
	}
    }
  queue_free(&reqq);
}


/* break an edge in a cycle */
static void
breakcycle(struct orderdata *od, Id *cycle)
{
  Pool *pool = od->trans->pool;
  Id ddegmin, ddegmax, ddeg;
  int k, l;
  struct _TransactionElement *te;

  l = 0;
  ddegmin = ddegmax = 0;
  for (k = 0; cycle[k + 1]; k += 2)
    {
      ddeg = od->edgedata[cycle[k + 1] + 1];
      if (ddeg > ddegmax)
	ddegmax = ddeg;
      if (!k || ddeg < ddegmin)
	{
	  l = k;
	  ddegmin = ddeg;
	  continue;
	}
      if (ddeg == ddegmin)
	{
	  if (havescripts(pool, od->tes[cycle[l]].p) && !havescripts(pool, od->tes[cycle[k]].p))
	    {
	      /* prefer k, as l comes from a package with contains scriptlets */
	      l = k;
	      ddegmin = ddeg;
	      continue;
	    }
	  /* same edge value, check for prereq */
	}
    }

  /* record brkoen cycle starting with the tail */
  queue_push(&od->cycles, od->cyclesdata.count);		/* offset into data */
  queue_push(&od->cycles, k / 2);				/* cycle elements */
  queue_push(&od->cycles, od->edgedata[cycle[l + 1] + 1]);	/* broken edge */
  od->ncycles++;
  for (k = l;;)
    {
      k += 2;
      if (!cycle[k + 1])
	k = 0;
      queue_push(&od->cyclesdata, cycle[k]);
      if (k == l)
	break;
    }
  queue_push(&od->cyclesdata, 0);	/* mark end */

  /* break that edge */
  od->edgedata[cycle[l + 1] + 1] |= TYPE_BROKEN;

#if 1
  if (ddegmin < TYPE_REQ)
    return;
#endif

  /* cycle recorded, print it */
  if (ddegmin >= TYPE_REQ && (ddegmax & TYPE_PREREQ) != 0)
    POOL_DEBUG(SAT_DEBUG_STATS, "CRITICAL ");
  POOL_DEBUG(SAT_DEBUG_STATS, "cycle: --> ");
  for (k = 0; cycle[k + 1]; k += 2)
    {
      te = od->tes +  cycle[k];
      if ((od->edgedata[cycle[k + 1] + 1] & TYPE_BROKEN) != 0)
        POOL_DEBUG(SAT_DEBUG_STATS, "%s ##%x##> ", solvid2str(pool, te->p), od->edgedata[cycle[k + 1] + 1]);
      else
        POOL_DEBUG(SAT_DEBUG_STATS, "%s --%x--> ", solvid2str(pool, te->p), od->edgedata[cycle[k + 1] + 1]);
    }
  POOL_DEBUG(SAT_DEBUG_STATS, "\n");
}

static inline void
dump_tes(struct orderdata *od)
{
  Pool *pool = od->trans->pool;
  int i, j;
  Queue obsq;
  struct _TransactionElement *te, *te2;

  queue_init(&obsq);
  for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
    {
      Solvable *s = pool->solvables + te->p;
      POOL_DEBUG(SAT_DEBUG_RESULT, "TE %4d: %c%s\n", i, s->repo == pool->installed ? '-' : '+', solvable2str(pool, s));
      if (s->repo != pool->installed)
        {
	  queue_empty(&obsq);
	  transaction_all_obs_pkgs(od->trans, te->p, &obsq);
	  for (j = 0; j < obsq.count; j++)
	    POOL_DEBUG(SAT_DEBUG_RESULT, "         -%s\n", solvid2str(pool, obsq.elements[j]));
	}
      for (j = te->edges; od->edgedata[j]; j += 2)
	{
	  te2 = od->tes + od->edgedata[j];
	  if ((od->edgedata[j + 1] & TYPE_BROKEN) == 0)
	    POOL_DEBUG(SAT_DEBUG_RESULT, "       --%x--> TE %4d: %s\n", od->edgedata[j + 1], od->edgedata[j], solvid2str(pool, te2->p));
	  else
	    POOL_DEBUG(SAT_DEBUG_RESULT, "       ##%x##> TE %4d: %s\n", od->edgedata[j + 1], od->edgedata[j], solvid2str(pool, te2->p));
	}
    }
}

#if 1
static void
reachable(struct orderdata *od, Id i)
{
  struct _TransactionElement *te = od->tes + i;
  int j, k;

  if (te->mark != 0)
    return;
  te->mark = 1;
  for (j = te->edges; (k = od->edgedata[j]) != 0; j += 2)
    {
      if ((od->edgedata[j + 1] & TYPE_BROKEN) != 0)
	continue;
      if (!od->tes[k].mark)
        reachable(od, k);
      if (od->tes[k].mark == 2)
	{
	  te->mark = 2;
	  return;
	}
    }
  te->mark = -1;
}
#endif

static void
addcycleedges(struct orderdata *od, Id *cycle, Queue *todo)
{
#if 0
  Transaction *trans = od->trans;
  Pool *pool = trans->pool;
#endif
  struct _TransactionElement *te;
  int i, j, k, tail;
#if 1
  int head;
#endif

#if 0
  printf("addcycleedges\n");
  for (i = 0; (j = cycle[i]) != 0; i++)
    printf("cycle %s\n", solvid2str(pool, od->tes[j].p));
#endif

  /* first add all the tail cycle edges */

  /* see what we can reach from the cycle */
  queue_empty(todo);
  for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
    te->mark = 0;
  for (i = 0; (j = cycle[i]) != 0; i++)
    {
      od->tes[j].mark = -1;
      queue_push(todo, j);
    }
  while (todo->count)
    {
      i = queue_pop(todo);
      te = od->tes + i;
      if (te->mark > 0)
	continue;
      te->mark = te->mark < 0 ? 2 : 1;
      for (j = te->edges; (k = od->edgedata[j]) != 0; j += 2)
	{
	  if ((od->edgedata[j + 1] & TYPE_BROKEN) != 0)
	    continue;
	  if (od->tes[k].mark > 0)
	    continue;	/* no need to visit again */
	  queue_push(todo, k);
	}
    }
  /* now all cycle TEs are marked with 2, all TEs reachable
   * from the cycle are marked with 1 */
  tail = cycle[0];
  od->tes[tail].mark = 1;	/* no need to add edges */

  for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
    {
      if (te->mark)
	continue;	/* reachable from cycle */
      for (j = te->edges; (k = od->edgedata[j]) != 0; j += 2)
	{
	  if ((od->edgedata[j + 1] & TYPE_BROKEN) != 0)
	    continue;
	  if (od->tes[k].mark != 2)
	    continue;
	  /* We found an edge to the cycle. Add an extra edge to the tail */
	  /* the TE was not reachable, so we're not creating a new cycle! */
#if 0
	  printf("adding TO TAIL cycle edge %d->%d %s->%s!\n", i, tail, solvid2str(pool, od->tes[i].p), solvid2str(pool, od->tes[tail].p));
#endif
	  j -= te->edges;	/* in case we move */
	  addteedge(od, i, tail, TYPE_CYCLETAIL);
	  j += te->edges;
	  break;	/* one edge is enough */
	}
    }

#if 1
  /* now add all head cycle edges */

  /* reset marks */
  for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
    te->mark = 0;
  head = 0;
  for (i = 0; (j = cycle[i]) != 0; i++)
    {
      head = j;
      od->tes[j].mark = 2;
    }
  /* first the head to save some time */
  te = od->tes + head;
  for (j = te->edges; (k = od->edgedata[j]) != 0; j += 2)
    {
      if ((od->edgedata[j + 1] & TYPE_BROKEN) != 0)
	continue;
      if (!od->tes[k].mark)
	reachable(od, k);
      if (od->tes[k].mark == -1)
	od->tes[k].mark = -2;	/* no need for another edge */
    }
  for (i = 0; cycle[i] != 0; i++)
    {
      if (cycle[i] == head)
	break;
      te = od->tes + cycle[i];
      for (j = te->edges; (k = od->edgedata[j]) != 0; j += 2)
	{
	  if ((od->edgedata[j + 1] & TYPE_BROKEN) != 0)
	    continue;
	  /* see if we can reach a cycle TE from k */
	  if (!od->tes[k].mark)
	    reachable(od, k);
	  if (od->tes[k].mark == -1)
	    {
#if 0
	      printf("adding FROM HEAD cycle edge %d->%d %s->%s [%s]!\n", head, k, solvid2str(pool, od->tes[head].p), solvid2str(pool, od->tes[k].p), solvid2str(pool, od->tes[cycle[i]].p));
#endif
	      addteedge(od, head, k, TYPE_CYCLEHEAD);
	      od->tes[k].mark = -2;	/* no need to add that one again */
	    }
	}
    }
#endif
}

void
transaction_order(Transaction *trans, int flags)
{
  Pool *pool = trans->pool;
  Queue *tr = &trans->steps;
  Repo *installed = pool->installed;
  Id p;
  Solvable *s;
  int i, j, k, numte, numedge;
  struct orderdata od;
  struct _TransactionElement *te;
  Queue todo, obsq, samerepoq, uninstq;
  int cycstart, cycel;
  Id *cycle;
  int oldcount;
  int start, now;
  Repo *lastrepo;
  int lastmedia;
  Id *temedianr;

  start = now = sat_timems(0);
  POOL_DEBUG(SAT_DEBUG_STATS, "ordering transaction\n");
  /* free old data if present */
  if (trans->orderdata)
    {
      struct _TransactionOrderdata *od = trans->orderdata;
      od->tes = sat_free(od->tes);
      od->invedgedata = sat_free(od->invedgedata);
      trans->orderdata = sat_free(trans->orderdata);
    }

  /* create a transaction element for every active component */
  numte = 0;
  for (i = 0; i < tr->count; i++)
    {
      p = tr->elements[i];
      s = pool->solvables + p;
      if (installed && s->repo == installed && trans->transaction_installed[p - installed->start])
	continue;
      numte++;
    }
  POOL_DEBUG(SAT_DEBUG_STATS, "transaction elements: %d\n", numte);
  if (!numte)
    return;	/* nothing to do... */

  numte++;	/* leave first one zero */
  memset(&od, 0, sizeof(od));
  od.trans = trans;
  od.ntes = numte;
  od.tes = sat_calloc(numte, sizeof(*od.tes));
  od.edgedata = sat_extend(0, 0, 1, sizeof(Id), EDGEDATA_BLOCK);
  od.edgedata[0] = 0;
  od.nedgedata = 1;
  queue_init(&od.cycles);

  /* initialize TEs */
  for (i = 0, te = od.tes + 1; i < tr->count; i++)
    {
      p = tr->elements[i];
      s = pool->solvables + p;
      if (installed && s->repo == installed && trans->transaction_installed[p - installed->start])
	continue;
      te->p = p;
      te++;
    }

  /* create dependency graph */
  for (i = 0; i < tr->count; i++)
    addsolvableedges(&od, pool->solvables + tr->elements[i]);

  /* count edges */
  numedge = 0;
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    for (j = te->edges; od.edgedata[j]; j += 2)
      numedge++;
  POOL_DEBUG(SAT_DEBUG_STATS, "edges: %d, edge space: %d\n", numedge, od.nedgedata / 2);
  POOL_DEBUG(SAT_DEBUG_STATS, "edge creation took %d ms\n", sat_timems(now));

#if 0
  dump_tes(&od);
#endif
  
  now = sat_timems(0);
  /* kill all cycles */
  queue_init(&todo);
  for (i = numte - 1; i > 0; i--)
    queue_push(&todo, i);

  while (todo.count)
    {
      i = queue_pop(&todo);
      /* printf("- look at TE %d\n", i); */
      if (i < 0)
	{
	  i = -i;
	  od.tes[i].mark = 2;	/* done with that one */
	  continue;
	}
      te = od.tes + i;
      if (te->mark == 2)
	continue;		/* already finished before */
      if (te->mark == 0)
	{
	  int edgestovisit = 0;
	  /* new node, visit edges */
	  for (j = te->edges; (k = od.edgedata[j]) != 0; j += 2)
	    {
	      if ((od.edgedata[j + 1] & TYPE_BROKEN) != 0)
		continue;
	      if (od.tes[k].mark == 2)
		continue;	/* no need to visit again */
	      if (!edgestovisit++)
	        queue_push(&todo, -i);	/* end of edges marker */
	      queue_push(&todo, k);
	    }
	  if (!edgestovisit)
	    te->mark = 2;	/* no edges, done with that one */
	  else
	    te->mark = 1;	/* under investigation */
	  continue;
	}
      /* oh no, we found a cycle */
      /* find start of cycle node (<0) */
      for (j = todo.count - 1; j >= 0; j--)
	if (todo.elements[j] == -i)
	  break;
      assert(j >= 0);
      cycstart = j;
      /* build te/edge chain */
      k = cycstart;
      for (j = k; j < todo.count; j++)
	if (todo.elements[j] < 0)
	  todo.elements[k++] = -todo.elements[j];
      cycel = k - cycstart;
      assert(cycel > 1);
      /* make room for edges, two extra element for cycle loop + terminating 0 */
      while (todo.count < cycstart + 2 * cycel + 2)
	queue_push(&todo, 0);
      cycle = todo.elements + cycstart;
      cycle[cycel] = i;		/* close the loop */
      cycle[2 * cycel + 1] = 0;	/* terminator */
      for (k = cycel; k > 0; k--)
	{
	  cycle[k * 2] = cycle[k];
	  te = od.tes + cycle[k - 1];
	  assert(te->mark == 1);
	  te->mark = 0;	/* reset investigation marker */
	  /* printf("searching for edge from %d to %d\n", cycle[k - 1], cycle[k]); */
	  for (j = te->edges; od.edgedata[j]; j += 2)
	    if (od.edgedata[j] == cycle[k])
	      break;
	  assert(od.edgedata[j]);
	  cycle[k * 2 - 1] = j;
	}
      /* now cycle looks like this: */
      /* te1 edge te2 edge te3 ... teN edge te1 0 */
      breakcycle(&od, cycle);
      /* restart with start of cycle */
      todo.count = cycstart + 1;
    }
  POOL_DEBUG(SAT_DEBUG_STATS, "cycles broken: %d\n", od.ncycles);
  POOL_DEBUG(SAT_DEBUG_STATS, "cycle breaking took %d ms\n", sat_timems(now));

  now = sat_timems(0);
  /* now go through all broken cycles and create cycle edges to help
     the ordering */
   for (i = od.cycles.count - 3; i >= 0; i -= 3)
     {
       if (od.cycles.elements[i + 2] >= TYPE_REQ)
         addcycleedges(&od, od.cyclesdata.elements + od.cycles.elements[i], &todo);
     }
   for (i = od.cycles.count - 3; i >= 0; i -= 3)
     {
       if (od.cycles.elements[i + 2] < TYPE_REQ)
         addcycleedges(&od, od.cyclesdata.elements + od.cycles.elements[i], &todo);
     }
  POOL_DEBUG(SAT_DEBUG_STATS, "cycle edge creation took %d ms\n", sat_timems(now));

#if 0
  dump_tes(&od);
#endif
  /* all edges are finally set up and there are no cycles, now the easy part.
   * Create an ordered transaction */
  now = sat_timems(0);
  /* first invert all edges */
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    te->mark = 1;	/* term 0 */
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    {
      for (j = te->edges; od.edgedata[j]; j += 2)
        {
	  if ((od.edgedata[j + 1] & TYPE_BROKEN) != 0)
	    continue;
	  od.tes[od.edgedata[j]].mark++;
	}
    }
  j = 1;
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    {
      te->mark += j;
      j = te->mark;
    }
  POOL_DEBUG(SAT_DEBUG_STATS, "invedge space: %d\n", j + 1);
  od.invedgedata = sat_calloc(j + 1, sizeof(Id));
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    {
      for (j = te->edges; od.edgedata[j]; j += 2)
        {
	  if ((od.edgedata[j + 1] & TYPE_BROKEN) != 0)
	    continue;
	  od.invedgedata[--od.tes[od.edgedata[j]].mark] = i;
	}
    }
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    te->edges = te->mark;	/* edges now points into invedgedata */
  od.edgedata = sat_free(od.edgedata);
  od.nedgedata = j + 1;

  /* now the final ordering */
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    te->mark = 0;
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    for (j = te->edges; od.invedgedata[j]; j++)
      od.tes[od.invedgedata[j]].mark++;

  queue_init(&samerepoq);
  queue_init(&uninstq);
  queue_empty(&todo);
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    if (te->mark == 0)
      {
	if (installed && pool->solvables[te->p].repo == installed)
          queue_push(&uninstq, i);
	else
          queue_push(&todo, i);
      }
  assert(todo.count > 0 || uninstq.count > 0);
  oldcount = tr->count;
  queue_empty(tr);

  queue_init(&obsq);
  
  lastrepo = 0;
  lastmedia = 0;
  temedianr = sat_calloc(numte, sizeof(Id));
  for (i = 1; i < numte; i++)
    {
      Solvable *s = pool->solvables + od.tes[i].p;
      if (installed && s->repo == installed)
	j = 1;
      else
        j = solvable_lookup_num(s, SOLVABLE_MEDIANR, 1);
      temedianr[i] = j;
    }
  for (;;)
    {
      /* select an TE i */
      if (uninstq.count)
	i = queue_shift(&uninstq);
      else if (samerepoq.count)
	i = queue_shift(&samerepoq);
      else if (todo.count)
	{
	  /* find next repo/media */
	  for (j = 0; j < todo.count; j++)
	    {
	      if (!j || temedianr[todo.elements[j]] < lastmedia)
		{
		  i = j;
		  lastmedia = temedianr[todo.elements[j]];
		}
	    }
	  lastrepo = pool->solvables[od.tes[todo.elements[i]].p].repo;

	  /* move all matching TEs to samerepoq */
	  for (i = j = 0; j < todo.count; j++)
	    {
	      int k = todo.elements[j];
	      if (temedianr[k] == lastmedia && pool->solvables[od.tes[k].p].repo == lastrepo)
		queue_push(&samerepoq, k);
	      else
		todo.elements[i++] = k;
	    }
	  todo.count = i;

	  assert(samerepoq.count);
	  i = queue_shift(&samerepoq);
	}
      else
	break;

      te = od.tes + i;
      queue_push(tr, te->p);
#if 0
printf("do %s [%d]\n", solvid2str(pool, te->p), temedianr[i]);
#endif
      s = pool->solvables + te->p;
      for (j = te->edges; od.invedgedata[j]; j++)
	{
	  struct _TransactionElement *te2 = od.tes + od.invedgedata[j];
	  assert(te2->mark > 0);
	  if (--te2->mark == 0)
	    {
	      Solvable *s = pool->solvables + te2->p;
#if 0
printf("free %s [%d]\n", solvid2str(pool, te2->p), temedianr[od.invedgedata[j]]);
#endif
	      if (installed && s->repo == installed)
	        queue_push(&uninstq, od.invedgedata[j]);
	      else if (s->repo == lastrepo && temedianr[od.invedgedata[j]] == lastmedia)
	        queue_push(&samerepoq, od.invedgedata[j]);
	      else
	        queue_push(&todo, od.invedgedata[j]);
	    }
	}
    }
  sat_free(temedianr);
  queue_free(&todo);
  queue_free(&samerepoq);
  queue_free(&uninstq);
  queue_free(&obsq);
  for (i = 1, te = od.tes + i; i < numte; i++, te++)
    assert(te->mark == 0);

  /* add back obsoleted packages */
  transaction_add_obsoleted(trans);
  assert(tr->count == oldcount);

  POOL_DEBUG(SAT_DEBUG_STATS, "creating new transaction took %d ms\n", sat_timems(now));
  POOL_DEBUG(SAT_DEBUG_STATS, "transaction ordering took %d ms\n", sat_timems(start));

  if ((flags & SOLVER_TRANSACTION_KEEP_ORDERDATA) != 0)
    {
      trans->orderdata = sat_calloc(1, sizeof(*trans->orderdata));
      trans->orderdata->tes = od.tes;
      trans->orderdata->ntes = numte;
      trans->orderdata->invedgedata = od.invedgedata;
      trans->orderdata->ninvedgedata = od.nedgedata;
    }
  else
    {
      sat_free(od.tes);
      sat_free(od.invedgedata);
    }
}


int
transaction_order_add_choices(Transaction *trans, Id chosen, Queue *choices)
{
  int i, j;
  struct _TransactionOrderdata *od = trans->orderdata;
  struct _TransactionElement *te;

  if (!od)
     return choices->count;
  if (!chosen)
    {
      /* initialization step */
      for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
	te->mark = 0;
      for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
	{
	  for (j = te->edges; od->invedgedata[j]; j++)
	    od->tes[od->invedgedata[j]].mark++;
	}
      for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
	if (!te->mark)
	  queue_push(choices, te->p);
      return choices->count;
    }
  for (i = 1, te = od->tes + i; i < od->ntes; i++, te++)
    if (te->p == chosen)
      break;
  if (i == od->ntes)
    return choices->count;
  if (te->mark > 0)
    {
      /* hey! out-of-order installation! */
      te->mark = -1;
    }
  for (j = te->edges; od->invedgedata[j]; j++)
    {
      te = od->tes + od->invedgedata[j];
      assert(te->mark > 0 || te->mark == -1);
      if (te->mark > 0 && --te->mark == 0)
	queue_push(choices, te->p);
    }
  return choices->count;
}

void
transaction_add_obsoleted(Transaction *trans)
{
  Pool *pool = trans->pool;
  Repo *installed = pool->installed;
  Id p;
  Solvable *s;
  int i, j, k, max;
  Map done;
  Queue obsq, *steps;

  if (!installed || !trans->steps.count)
    return;
  /* calculate upper bound */
  max = 0;
  FOR_REPO_SOLVABLES(installed, p, s)
    if (MAPTST(&trans->transactsmap, p))
      max++;
  if (!max)
    return;
  /* make room */
  steps = &trans->steps;
  queue_insertn(steps, 0, max);

  /* now add em */
  map_init(&done, installed->end - installed->start);
  queue_init(&obsq);
  for (j = 0, i = max; i < steps->count; i++)
    {
      p = trans->steps.elements[i];
      if (pool->solvables[p].repo == installed)
	{
	  if (!trans->transaction_installed[p - pool->installed->start])
	    trans->steps.elements[j++] = p;
	  continue;
	}
      trans->steps.elements[j++] = p;
      queue_empty(&obsq);
      transaction_all_obs_pkgs(trans, p, &obsq);
      for (k = 0; k < obsq.count; k++)
	{
	  p = obsq.elements[k];
	  assert(p >= installed->start && p < installed->end);
	  if (MAPTST(&done, p - installed->start))
	    continue;
	  MAPSET(&done, p - installed->start);
	  trans->steps.elements[j++] = p;
	}
    }

  /* free unneeded space */
  queue_truncate(steps, j);
  map_free(&done);
  queue_free(&obsq);
}

static void
transaction_check_pkg(Transaction *trans, Id tepkg, Id pkg, Map *ins, Map *seen, int onlyprereq, Id noconfpkg, int depth)
{
  Pool *pool = trans->pool;
  Id p, pp;
  Solvable *s;
  int good;

  if (MAPTST(seen, pkg))
    return;
  MAPSET(seen, pkg);
  s = pool->solvables + pkg;
#if 0
  printf("- %*s%c%s\n", depth * 2, "", s->repo == pool->installed ? '-' : '+', solvable2str(pool, s));
#endif
  if (s->requires)
    {
      Id req, *reqp;
      int inpre = 0;
      reqp = s->repo->idarraydata + s->requires;
      while ((req = *reqp++) != 0)
	{
          if (req == SOLVABLE_PREREQMARKER)
	    {
	      inpre = 1;
	      continue;
	    }
	  if (onlyprereq && !inpre)
	    continue;
	  if (!strncmp(id2str(pool, req), "rpmlib(", 7))
	    continue;
	  good = 0;
	  /* first check kept packages, then freshly installed, then not yet uninstalled */
	  FOR_PROVIDES(p, pp, req)
	    {
	      if (!MAPTST(ins, p))
		continue;
	      if (MAPTST(&trans->transactsmap, p))
		continue;
	      good++;
	      transaction_check_pkg(trans, tepkg, p, ins, seen, 0, noconfpkg, depth + 1);
	    }
	  if (!good)
	    {
	      FOR_PROVIDES(p, pp, req)
		{
		  if (!MAPTST(ins, p))
		    continue;
		  if (pool->solvables[p].repo == pool->installed)
		    continue;
		  good++;
		  transaction_check_pkg(trans, tepkg, p, ins, seen, 0, noconfpkg, depth + 1);
		}
	    }
	  if (!good)
	    {
	      FOR_PROVIDES(p, pp, req)
		{
		  if (!MAPTST(ins, p))
		    continue;
		  good++;
		  transaction_check_pkg(trans, tepkg, p, ins, seen, 0, noconfpkg, depth + 1);
		}
	    }
	  if (!good)
	    {
	      POOL_DEBUG(SAT_DEBUG_RESULT, "  %c%s: nothing provides %s needed by %c%s\n", pool->solvables[tepkg].repo == pool->installed ? '-' : '+', solvid2str(pool, tepkg), dep2str(pool, req), s->repo == pool->installed ? '-' : '+', solvable2str(pool, s));
	    }
	}
    }
}

void
transaction_check_order(Transaction *trans)
{
  Pool *pool = trans->pool;
  Solvable *s;
  Id p, lastins;
  Map ins, seen;
  int i;

  POOL_DEBUG(SAT_WARN, "\nchecking transaction order...\n");
  map_init(&ins, pool->nsolvables);
  map_init(&seen, pool->nsolvables);
  if (pool->installed)
    FOR_REPO_SOLVABLES(pool->installed, p, s)
      MAPSET(&ins, p);
  lastins = 0;
  for (i = 0; i < trans->steps.count; i++)
    {
      p = trans->steps.elements[i];
      s = pool->solvables + p;
      if (s->repo != pool->installed)
	lastins = p;
      if (s->repo != pool->installed)
	MAPSET(&ins, p);
      if (havescripts(pool, p))
	{
	  MAPZERO(&seen);
	  transaction_check_pkg(trans, p, p, &ins, &seen, 1, lastins, 0);
	}
      if (s->repo == pool->installed)
	MAPCLR(&ins, p);
    }
  map_free(&seen);
  map_free(&ins);
  POOL_DEBUG(SAT_WARN, "transaction order check done.\n");
}
