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Artifact 79dd0c4340c8011d8d07e989ce89594eeaebe527

File src/timeline.c part of check-in [b6e22e62cf] - Attempting to rationalize the tagging and branching logic. The "branch" command has been resurrected and appears to work now. The "tag branch" command has been removed. Special tags "newbranch" and "closed" used to manage branches. New changes are not well-tested - use with caution. You must "rebuild" when upgrading through this version. by drh on 2009-01-20 16:51:19.

/*
** Copyright (c) 2007 D. Richard Hipp
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public
** License version 2 as published by the Free Software Foundation.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
** General Public License for more details.
** 
** You should have received a copy of the GNU General Public
** License along with this library; if not, write to the
** Free Software Foundation, Inc., 59 Temple Place - Suite 330,
** Boston, MA  02111-1307, USA.
**
** Author contact information:
**   drh@hwaci.com
**   http://www.hwaci.com/drh/
**
*******************************************************************************
**
** This file contains code to implement the timeline web page
**
*/
#include <string.h>
#include <time.h>
#include "config.h"
#include "timeline.h"

/*
** Generate a hyperlink to a version.
*/
void hyperlink_to_uuid(const char *zUuid){
  char zShortUuid[UUID_SIZE+1];
  sprintf(zShortUuid, "%.10s", zUuid);
  if( g.okHistory ){
    @ <a href="%s(g.zBaseURL)/info/%s(zUuid)">[%s(zShortUuid)]</a>
  }else{
    @ <b>[%s(zShortUuid)]</b>
  }
}

/*
** Generate a hyperlink that invokes javascript to highlight
** a version on mouseover.
*/
void hyperlink_to_uuid_with_mouseover(
  const char *zUuid,   /* The UUID to display */
  const char *zIn,     /* Javascript proc for mouseover */
  const char *zOut,    /* Javascript proc for mouseout */
  int id               /* Argument to javascript procs */
){
  char zShortUuid[UUID_SIZE+1];
  sprintf(zShortUuid, "%.10s", zUuid);
  if( g.okHistory ){
    @ <a onmouseover='%s(zIn)("m%d(id)")' onmouseout='%s(zOut)("m%d(id)")'
    @    href="%s(g.zBaseURL)/vinfo/%s(zUuid)">[%s(zShortUuid)]</a>
  }else{
    @ <b onmouseover='%s(zIn)("m%d(id)")' onmouseout='%s(zOut)("m%d(id)")'>
    @ [%s(zShortUuid)]</b>
  }
}

/*
** Generate a hyperlink to a diff between two versions.
*/
void hyperlink_to_diff(const char *zV1, const char *zV2){
  if( g.okHistory ){
    if( zV2==0 ){
      @ <a href="%s(g.zBaseURL)/diff?v2=%s(zV1)">[diff]</a>
    }else{
      @ <a href="%s(g.zBaseURL)/diff?v1=%s(zV1)&v2=%s(zV2)">[diff]</a>
    }
  }
}

/*
** Count the number of non-branch children for the given check-in.
** A non-branch child is a child that omits the "newbranch" tag.
*/
int count_nonbranch_children(int pid){
  int nNonBranch;

  nNonBranch = db_int(0,  
    "SELECT count(*) FROM plink"
    " WHERE pid=%d"
    "   AND NOT EXISTS(SELECT 1 FROM tagxref"
                    "   WHERE tagid=%d"
                    "     AND rid=cid"
                    "     AND tagtype>0"
                    " )",
    pid, TAG_NEWBRANCH
  );
  return nNonBranch;
}

/*
** Output a timeline in the web format given a query.  The query
** should return these columns:
**
**    0.  rid
**    1.  UUID
**    2.  Date/Time
**    3.  Comment string
**    4.  User
**    5.  Number of non-merge children
**    6.  Number of parents
**    7.  True if is a leaf
**    8.  background color
**    9.  type ("ci", "w")
**   10.  list of symbolic tags.
*/
void www_print_timeline(
  Stmt *pQuery
){
  int wikiFlags;
  int mxWikiLen;
  Blob comment;
  char zPrevDate[20];
  zPrevDate[0] = 0;

  mxWikiLen = db_get_int("timeline-max-comment", 0);
  if( db_get_boolean("timeline-block-markup", 0) ){
    wikiFlags = WIKI_INLINE;
  }else{
    wikiFlags = WIKI_INLINE | WIKI_NOBLOCK;
  }

  db_multi_exec(
     "CREATE TEMP TABLE IF NOT EXISTS seen(rid INTEGER PRIMARY KEY);"
     "DELETE FROM seen;"
  );
  @ <table cellspacing=0 border=0 cellpadding=0>
  blob_zero(&comment);
  while( db_step(pQuery)==SQLITE_ROW ){
    int rid = db_column_int(pQuery, 0);
    const char *zUuid = db_column_text(pQuery, 1);
    int nPChild = db_column_int(pQuery, 5);
    int nParent = db_column_int(pQuery, 6);
    int isLeaf = db_column_int(pQuery, 7);
    const char *zBgClr = db_column_text(pQuery, 8);
    const char *zDate = db_column_text(pQuery, 2);
    const char *zType = db_column_text(pQuery, 9);
    const char *zUser = db_column_text(pQuery, 4);
    const char *zTagList = db_column_text(pQuery, 10);
    db_multi_exec("INSERT OR IGNORE INTO seen VALUES(%d)", rid);
    if( memcmp(zDate, zPrevDate, 10) ){
      sprintf(zPrevDate, "%.10s", zDate);
      @ <tr><td colspan=3>
      @   <div class="divider">%s(zPrevDate)</div>
      @ </td></tr>
    }
    @ <tr>
    @ <td valign="top">%s(&zDate[11])</td>
    @ <td width="20" align="center" valign="top">
    @ <font id="m%d(rid)" size="+1" color="white">*</font></td>
    if( zBgClr && zBgClr[0] ){
      @ <td valign="top" align="left" bgcolor="%h(zBgClr)">
    }else{
      @ <td valign="top" align="left">
    }
    if( zType[0]=='c' ){
      hyperlink_to_uuid_with_mouseover(zUuid, "xin", "xout", rid);
      if( nParent>1 ){
        @ <b>Merge</b> 
      }
      if( nPChild>1 ){
        if( count_nonbranch_children(rid)>1 ){
          @ <b>Fork</b>
        }else{
          @ <b>Branch</b>
        }
      }
      if( isLeaf ){
        @ <b>Leaf</b>
      }
    }else{
      hyperlink_to_uuid(zUuid);
    }
    db_column_blob(pQuery, 3, &comment);
    if( mxWikiLen>0 && blob_size(&comment)>mxWikiLen ){
      Blob truncated;
      blob_zero(&truncated);
      blob_append(&truncated, blob_buffer(&comment), mxWikiLen);
      blob_append(&truncated, "...", 3);
      wiki_convert(&truncated, 0, wikiFlags);
      blob_reset(&truncated);
    }else{
      wiki_convert(&comment, 0, wikiFlags);
    }
    blob_reset(&comment);
    if( zTagList && zTagList[0] ){
      @ (user: %h(zUser), tags: %h(zTagList))</td></tr>
    }else{
      @ (user: %h(zUser))</td></tr>
    }
  }
  @ </table>
}

/*
** Create a temporary table suitable for storing timeline data.
*/
static void timeline_temp_table(void){
  static const char zSql[] = 
    @ CREATE TEMP TABLE IF NOT EXISTS timeline(
    @   rid INTEGER PRIMARY KEY,
    @   uuid TEXT,
    @   timestamp TEXT,
    @   comment TEXT,
    @   user TEXT,
    @   nchild INTEGER,
    @   nparent INTEGER,
    @   isleaf BOOLEAN,
    @   bgcolor TEXT,
    @   etype TEXT,
    @   taglist TEXT
    @ )
  ;
  db_multi_exec(zSql);
}

/*
** Return a pointer to a constant string that forms the basis
** for a timeline query for the WWW interface.
*/
const char *timeline_query_for_www(void){
  static const char zBaseSql[] =
    @ SELECT
    @   blob.rid,
    @   uuid,
    @   datetime(event.mtime,'localtime') AS timestamp,
    @   coalesce(ecomment, comment),
    @   coalesce(euser, user),
    @   (SELECT count(*) FROM plink WHERE pid=blob.rid AND isprim=1),
    @   (SELECT count(*) FROM plink WHERE cid=blob.rid),
    @   NOT EXISTS (SELECT 1 FROM plink WHERE pid=blob.rid),
    @   coalesce(bgcolor, brbgcolor),
    @   event.type,
    @   (SELECT group_concat(substr(tagname,5), ', ') FROM tag, tagxref
    @     WHERE tagname GLOB 'sym-*' AND tag.tagid=tagxref.tagid
    @       AND tagxref.rid=blob.rid AND tagxref.tagtype>0)
    @  FROM event JOIN blob 
    @ WHERE blob.rid=event.objid
  ;
  return zBaseSql;
}

/*
** Generate a submenu element with a single parameter change.
*/
static void timeline_submenu(
  HQuery *pUrl,            /* Base URL */
  const char *zMenuName,   /* Submenu name */
  const char *zParam,      /* Parameter value to add or change */
  const char *zValue,      /* Value of the new parameter */
  const char *zRemove      /* Parameter to omit */
){
  style_submenu_element(zMenuName, zMenuName, "%s",
                        url_render(pUrl, zParam, zValue, zRemove, 0));
}

/*
** WEBPAGE: timeline
**
** Query parameters:
**
**    a=TIMESTAMP    after this date
**    b=TIMESTAMP    before this date.
**    n=COUNT        number of events in output
**    p=RID          artifact RID and up to COUNT parents and ancestors
**    d=RID          artifact RID and up to COUNT descendants
**    u=USER         only if belonging to this user
**    y=TYPE         'ci', 'w', 't'
**
** p= and d= can appear individually or together.  If either p= or d=
** appear, then u=, y=, a=, and b= are ignored.
**
** If a= and b= appear, only a= is used.  If neither appear, the most
** recent events are choosen.
**
** If n= is missing, the default count is 20.
*/
void page_timeline(void){
  Stmt q;                            /* Query used to generate the timeline */
  Blob sql;                          /* text of SQL used to generate timeline */
  Blob desc;                         /* Description of the timeline */
  int nEntry = atoi(PD("n","20"));   /* Max number of entries on timeline */
  int p_rid = atoi(PD("p","0"));     /* artifact p and its parents */
  int d_rid = atoi(PD("d","0"));     /* artifact d and its descendants */
  const char *zUser = P("u");        /* All entries by this user if not NULL */
  const char *zType = PD("y","all"); /* Type of events.  All if NULL */
  const char *zAfter = P("a");       /* Events after this time */
  const char *zBefore = P("b");      /* Events before this time */
  HQuery url;                        /* URL for various branch links */

  /* To view the timeline, must have permission to read project data.
  */
  login_check_credentials();
  if( !g.okRead ){ login_needed(); return; }

  style_header("Timeline");
  login_anonymous_available();
  timeline_temp_table();
  blob_zero(&sql);
  blob_zero(&desc);
  blob_append(&sql, "INSERT OR IGNORE INTO timeline ", -1);
  blob_append(&sql, timeline_query_for_www(), -1);
  if( p_rid || d_rid ){
    /* If p= or d= is present, ignore all other parameters other than n= */
    char *zUuid;
    int np, nd;

    if( p_rid && d_rid && p_rid!=d_rid ) p_rid = d_rid;
    db_multi_exec(
       "CREATE TEMP TABLE IF NOT EXISTS ok(rid INTEGER PRIMARY KEY)"
    );
    zUuid = db_text("", "SELECT uuid FROM blob WHERE rid=%d",
                         p_rid ? p_rid : d_rid);
    blob_appendf(&sql, " AND event.objid IN ok");
    nd = 0;
    if( d_rid ){
      compute_descendants(d_rid, nEntry);
      nd = db_int(0, "SELECT count(*)-1 FROM ok");
      if( nd>0 ){
        db_multi_exec("%s", blob_str(&sql));
        blob_appendf(&desc, "%d descendants", nd);
      }
      db_multi_exec("DELETE FROM ok");
    }
    if( p_rid ){
      compute_ancestors(p_rid, nEntry);
      np = db_int(0, "SELECT count(*)-1 FROM ok");
      if( np>0 ){
        if( nd>0 ) blob_appendf(&desc, " and ");
        blob_appendf(&desc, "%d ancestors", np);
        db_multi_exec("%s", blob_str(&sql));
      }
    }
    if( g.okHistory ){
      blob_appendf(&desc, " of <a href='%s/info/%s'>[%.10s]</a>",
                   g.zBaseURL, zUuid, zUuid);
    }else{
      blob_appendf(&desc, " of [%.10s]", zUuid);
    }
    db_prepare(&q, "SELECT * FROM timeline ORDER BY timestamp DESC");
  }else{
    int n;
    const char *zEType = "event";
    char *zDate;
    char *zNEntry = mprintf("%d", nEntry);
    url_initialize(&url, "timeline");
    url_add_parameter(&url, "n", zNEntry);
    if( zType[0]!='a' ){
      blob_appendf(&sql, " AND event.type=%Q", zType);
      url_add_parameter(&url, "y", zType);
      if( zType[0]=='c' ){
        zEType = "checkin";
      }else if( zType[0]=='w' ){
        zEType = "wiki edit";
      }else if( zType[0]=='t' ){
        zEType = "ticket change";
      }
    }
    if( zUser ){
      blob_appendf(&sql, " AND event.user=%Q", zUser);
      url_add_parameter(&url, "u", zUser);
    }
    if( zAfter ){
      while( isspace(zAfter[0]) ){ zAfter++; }
      if( zAfter[0] ){
        blob_appendf(&sql, 
           " AND event.mtime>=(SELECT julianday(%Q, 'utc'))"
           " ORDER BY event.mtime ASC", zAfter);
        url_add_parameter(&url, "a", zAfter);
        zBefore = 0;
      }else{
        zAfter = 0;
      }
    }else if( zBefore ){
      while( isspace(zBefore[0]) ){ zBefore++; }
      if( zBefore[0] ){
        blob_appendf(&sql, 
           " AND event.mtime<=(SELECT julianday(%Q, 'utc'))"
           " ORDER BY event.mtime DESC", zBefore);
        url_add_parameter(&url, "b", zBefore);
       }else{
        zBefore = 0;
      }
    }else{
      blob_appendf(&sql, " ORDER BY event.mtime DESC");
    }
    blob_appendf(&sql, " LIMIT %d", nEntry);
    db_multi_exec("%s", blob_str(&sql));

    n = db_int(0, "SELECT count(*) FROM timeline");
    if( n<nEntry && zAfter ){
      cgi_redirect(url_render(&url, "a", 0, "b", 0));
    }
    if( zAfter==0 && zBefore==0 ){
      blob_appendf(&desc, "%d most recent %ss", n, zEType);
    }else{
      blob_appendf(&desc, "%d %ss", n, zEType);
    }
    if( zUser ){
      blob_appendf(&desc, " by user %h", zUser);
    }
    if( zAfter ){
      blob_appendf(&desc, " occurring on or after %h.<br>", zAfter);
    }else if( zBefore ){
      blob_appendf(&desc, " occurring on or before %h.<br>", zBefore);
    }
    if( g.okHistory ){
      if( zAfter || n==nEntry ){
        zDate = db_text(0, "SELECT min(timestamp) FROM timeline");
        timeline_submenu(&url, "Older", "b", zDate, "a");
        free(zDate);
      }
      if( zBefore || (zAfter && n==nEntry) ){
        zDate = db_text(0, "SELECT max(timestamp) FROM timeline");
        timeline_submenu(&url, "Newer", "a", zDate, "b");
        free(zDate);
      }else{
        if( zType[0]!='a' ){
          timeline_submenu(&url, "All Types", "y", "all", 0);
        }
        if( zType[0]!='w' ){
          timeline_submenu(&url, "Wiki Only", "y", "w", 0);
        }
        if( zType[0]!='c' ){
          timeline_submenu(&url, "Checkins Only", "y", "ci", 0);
        }
        if( zType[0]!='t' ){
          timeline_submenu(&url, "Tickets Only", "y", "t", 0);
        }
      }
      if( nEntry>20 ){
        timeline_submenu(&url, "20 Events", "n", "20", 0);
      }
      if( nEntry<200 ){
        timeline_submenu(&url, "200 Events", "n", "200", 0);
      }
    }
  }
  blob_zero(&sql);
  db_prepare(&q, "SELECT * FROM timeline ORDER BY timestamp DESC");
  @ <h2>%b(&desc)</h2>
  blob_reset(&desc);
  www_print_timeline(&q);
  db_finalize(&q);

  @ <script>
  @ var parentof = new Object();
  @ var childof = new Object();
  db_prepare(&q, "SELECT rid FROM timeline");
  while( db_step(&q)==SQLITE_ROW ){
    int rid = db_column_int(&q, 0);
    Stmt q2;
    const char *zSep;
    Blob *pOut = cgi_output_blob();

    db_prepare(&q2, "SELECT pid FROM plink WHERE cid=%d", rid);
    zSep = "";
    blob_appendf(pOut, "parentof[\"m%d\"] = [", rid);
    while( db_step(&q2)==SQLITE_ROW ){
      int pid = db_column_int(&q2, 0);
      blob_appendf(pOut, "%s\"m%d\"", zSep, pid);
      zSep = ",";
    }
    db_finalize(&q2);
    blob_appendf(pOut, "];\n");
    db_prepare(&q2, "SELECT cid FROM plink WHERE pid=%d", rid);
    zSep = "";
    blob_appendf(pOut, "childof[\"m%d\"] = [", rid);
    while( db_step(&q2)==SQLITE_ROW ){
      int pid = db_column_int(&q2, 0);
      blob_appendf(pOut, "%s\"m%d\"", zSep, pid);
      zSep = ",";
    }
    db_finalize(&q2);
    blob_appendf(pOut, "];\n");
  }
  db_finalize(&q);
  @ function setall(value){
  @   for(var x in parentof){
  @     setone(x,value);
  @   }
  @ }
  @ setall("#ffffff");
  @ function setone(id, clr){
  @   if( parentof[id]==null ) return 0;
  @   var w = document.getElementById(id);
  @   if( w.style.color==clr ){
  @     return 0
  @   }else{
  @     w.style.color = clr
  @     return 1
  @   }
  @ }
  @ function xin(id) {
  @   setall("#ffffff");
  @   setone(id,"#ff0000");
  @   set_children(id, "#b0b0b0");
  @   set_parents(id, "#b0b0b0");
  @   for(var x in parentof[id]){
  @     var pid = parentof[id][x]
  @     var w = document.getElementById(pid);
  @     if( w!=null ){
  @       w.style.color = "#000000";
  @     }
  @   }
  @   for(var x in childof[id]){
  @     var cid = childof[id][x]
  @     var w = document.getElementById(cid);
  @     if( w!=null ){
  @       w.style.color = "#000000";
  @     }
  @   }
  @ }
  @ function xout(id) {
  @   /* setall("#000000"); */
  @ }
  @ function set_parents(id, clr){
  @   var plist = parentof[id];
  @   if( plist==null ) return;
  @   for(var x in plist){
  @     var pid = plist[x];
  @     if( setone(pid,clr)==1 ){
  @       set_parents(pid,clr);
  @     }
  @   }
  @ }
  @ function set_children(id,clr){
  @   var clist = childof[id];
  @   if( clist==null ) return;
  @   for(var x in clist){
  @     var cid = clist[x];
  @     if( setone(cid,clr)==1 ){
  @       set_children(cid,clr);
  @     }
  @   }
  @ }
  @ </script>
  style_footer();
}

/*
** The input query q selects various records.  Print a human-readable
** summary of those records.
**
** Limit the number of entries printed to nLine.
** 
** The query should return these columns:
**
**    0.  rid
**    1.  uuid
**    2.  Date/Time
**    3.  Comment string and user
**    4.  Number of non-merge children
**    5.  Number of parents
*/
void print_timeline(Stmt *q, int mxLine){
  int nLine = 0;
  char zPrevDate[20];
  const char *zCurrentUuid=0;
  zPrevDate[0] = 0;

  if( g.localOpen ){
    int rid = db_lget_int("checkout", 0);
    zCurrentUuid = db_text(0, "SELECT uuid FROM blob WHERE rid=%d", rid);
  }

  while( db_step(q)==SQLITE_ROW && nLine<=mxLine ){
    int rid = db_column_int(q, 0);
    const char *zId = db_column_text(q, 1);
    const char *zDate = db_column_text(q, 2);
    const char *zCom = db_column_text(q, 3);
    int nChild = db_column_int(q, 4);
    int nParent = db_column_int(q, 5);
    char *zFree = 0;
    int n = 0;
    char zPrefix[80];
    char zUuid[UUID_SIZE+1];
    
    sprintf(zUuid, "%.10s", zId);
    if( memcmp(zDate, zPrevDate, 10) ){
      printf("=== %.10s ===\n", zDate);
      memcpy(zPrevDate, zDate, 10);
      nLine++;
    }
    if( zCom==0 ) zCom = "";
    printf("%.8s ", &zDate[11]);
    zPrefix[0] = 0;
    if( nParent>1 ){
      sqlite3_snprintf(sizeof(zPrefix), zPrefix, "*MERGE* ");
      n = strlen(zPrefix);
    }
    if( nChild>1 ){
      const char *zBrType;
      if( count_nonbranch_children(rid)>1 ){
        zBrType = "*FORK* ";
      }else{
        zBrType = "*BRANCH* ";
      }
      sqlite3_snprintf(sizeof(zPrefix)-n, &zPrefix[n], zBrType);
      n = strlen(zPrefix);
    }
    if( zCurrentUuid && strcmp(zCurrentUuid,zId)==0 ){
      sqlite3_snprintf(sizeof(zPrefix)-n, &zPrefix[n], "*CURRENT* ");
      n += strlen(zPrefix);
    }
    zFree = sqlite3_mprintf("[%.10s] %s%s", zUuid, zPrefix, zCom);
    nLine += comment_print(zFree, 9, 79);
    sqlite3_free(zFree);
  }
}

/*
** Return a pointer to a static string that forms the basis for
** a timeline query for display on a TTY.
*/
const char *timeline_query_for_tty(void){
  static const char zBaseSql[] = 
    @ SELECT
    @   blob.rid,
    @   uuid,
    @   datetime(event.mtime,'localtime'),
    @   coalesce(ecomment,comment)
    @     || ' (user: ' || coalesce(euser,user,'?')
    @     || (SELECT case when length(x)>0 then ' tags: ' || x else '' end
    @           FROM (SELECT group_concat(substr(tagname,5), ', ') AS x
    @                   FROM tag, tagxref
    @                  WHERE tagname GLOB 'sym-*' AND tag.tagid=tagxref.tagid
    @                    AND tagxref.rid=blob.rid AND tagxref.tagtype>0))
    @     || ')',
    @   (SELECT count(*) FROM plink WHERE pid=blob.rid AND isprim),
    @   (SELECT count(*) FROM plink WHERE cid=blob.rid)
    @ FROM event, blob
    @ WHERE blob.rid=event.objid
  ;
  return zBaseSql;
}

/*
** Equivalent to timeline_query_for_tty(), except that:
**
** a) accepts a the -type=XX flag to set the event type to filter on.
**    The values of XX are the same as supported by the /timeline page.
**
** b) The returned string must be freed using free().
*/
char * timeline_query_for_tty_m(void){
  Blob bl;
  char const * zType = 0;
  blob_zero(&bl);
  blob_append( &bl, timeline_query_for_tty(), -1 );
  zType = find_option( "type", "t", 1 );
  if( zType && *zType )
  {
      blob_appendf( &bl, " AND event.type=%Q", zType );
  }
  return blob_buffer(&bl);
}

/*
** COMMAND: timeline
**
** Usage: %fossil timeline ?WHEN? ?BASELINE|DATETIME? ?-n|--count N? ?-t|--type TYPE?
**
** Print a summary of activity going backwards in date and time
** specified or from the current date and time if no arguments
** are given.  Show as many as N (default 20) check-ins.  The
** WHEN argument can be any unique abbreviation of one of these
** keywords:
**
**     before
**     after
**     descendants | children
**     ancestors | parents
**
** The BASELINE can be any unique prefix of 4 characters or more.
** The DATETIME should be in the ISO8601 format.  For
** examples: "2007-08-18 07:21:21".  You can also say "current"
** for the current version or "now" for the current time.
**
** The optional TYPE argument may any types supported by the /timeline
** page. For example:
**
**     w  = wiki commits only
**     ci = file commits only
**     t  = tickets only
*/
void timeline_cmd(void){
  Stmt q;
  int n, k;
  const char *zCount;
  const char *zType;
  char *zOrigin;
  char *zDate;
  char *zSQL;
  int objid = 0;
  Blob uuid;
  int mode = 1 ;       /* 1: before  2:after  3:children  4:parents */
  db_find_and_open_repository(1);
  zCount = find_option("count","n",1);
  zType = find_option("type","t",1);
  if( zCount ){
    n = atoi(zCount);
  }else{
    n = 20;
  }
  if( g.argc>=4 ){
    k = strlen(g.argv[2]);
    if( strncmp(g.argv[2],"before",k)==0 ){
      mode = 1;
    }else if( strncmp(g.argv[2],"after",k)==0 && k>1 ){
      mode = 2;
    }else if( strncmp(g.argv[2],"descendants",k)==0 ){
      mode = 3;
    }else if( strncmp(g.argv[2],"children",k)==0 ){
      mode = 3;
    }else if( strncmp(g.argv[2],"ancestors",k)==0 && k>1 ){
      mode = 4;
    }else if( strncmp(g.argv[2],"parents",k)==0 ){
      mode = 4;
    }else if(!zType && !zCount){
      usage("?WHEN? ?BASELINE|DATETIME? ?-n|--count N? ?-t TYPE?");
    }
    if( '-' != *g.argv[3] ){
	zOrigin = g.argv[3];
    }else{
	zOrigin = "now";
    }
  }else if( g.argc==3 ){
    zOrigin = g.argv[2];
  }else{
    zOrigin = "now";
  }
  k = strlen(zOrigin);
  blob_zero(&uuid);
  blob_append(&uuid, zOrigin, -1);
  if( strcmp(zOrigin, "now")==0 ){
    if( mode==3 || mode==4 ){
      fossil_fatal("cannot compute descendants or ancestors of a date");
    }
    zDate = mprintf("(SELECT datetime('now'))");
  }else if( strncmp(zOrigin, "current", k)==0 ){
    if( !g.localOpen ){
      fossil_fatal("must be within a local checkout to use 'current'");
    }
    objid = db_lget_int("checkout",0);
    zDate = mprintf("(SELECT mtime FROM plink WHERE cid=%d)", objid);
  }else if( name_to_uuid(&uuid, 0)==0 ){
    objid = db_int(0, "SELECT rid FROM blob WHERE uuid=%B", &uuid);
    zDate = mprintf("(SELECT mtime FROM plink WHERE cid=%d)", objid);
  }else{
    if( mode==3 || mode==4 ){
      fossil_fatal("cannot compute descendants or ancestors of a date");
    }
    zDate = mprintf("(SELECT julianday(%Q, 'utc'))", zOrigin);
  }
  zSQL = mprintf("%z AND event.mtime %s %s",
     timeline_query_for_tty_m(),
     (mode==1 || mode==4) ? "<=" : ">=",
     zDate
  );
  if( mode==3 || mode==4 ){
    db_multi_exec("CREATE TEMP TABLE ok(rid INTEGER PRIMARY KEY)");
    if( mode==3 ){
      compute_descendants(objid, n);
    }else{
      compute_ancestors(objid, n);
    }
    zSQL = mprintf("%z AND blob.rid IN ok", zSQL);
  }
  if( zType && (zType[0]!='a') ){
      zSQL = mprintf( "%z AND event.type=%Q ", zSQL, zType);
  }

  zSQL = mprintf("%z ORDER BY event.mtime DESC", zSQL);
  db_prepare(&q, zSQL);
  free( zSQL );
  print_timeline(&q, n);
  db_finalize(&q);
}

/*
** This is a version of the "localtime()" function from the standard
** C library.  It converts a unix timestamp (seconds since 1970) into
** a broken-out local time structure.
**
** This modified version of localtime() works like the library localtime()
** by default.  Except if the timeline-utc property is set, this routine
** uses gmttime() instead.  Thus by setting the timeline-utc property, we
** can get all localtimes to be displayed at UTC time.
*/
struct tm *fossil_localtime(const time_t *clock){
  if( g.fTimeFormat==0 ){
    if( db_get_int("timeline-utc", 1) ){
      g.fTimeFormat = 1;
    }else{
      g.fTimeFormat = 2;
    }
  }
  if( g.fTimeFormat==1 ){
    return gmtime(clock);
  }else{
    return localtime(clock);
  }
}