Php > Algorithms sample source codes

This code displays a graphical tree (similar to that of Windows' Explorer)

This code displays a graphical tree (similar to that of Windows' Explorer)
from the contents of a database table

<?php //  -*-  C++  -*- 

/*  Here  are  the  database  definitions  (for  Solid)  that  i  use  in  this  code. 
  *  It  should  not  be  hard  to  adapt  it  to  another  database. 
  */ 

/* 
CREATE  TABLE  dirent_types  ( 
        id        INTEGER  NOT  NULL, 
        icon        VARCHAR(50), 
        name        VARCHAR(50), 
        PRIMARY  KEY(id) 
); 

INSERT  INTO  dirent_types  VALUES(1,  'folderclosed',  'Directory'); 
INSERT  INTO  dirent_types  VALUES(2,  'document',  'File'); 

CREATE  TABLE  directory  ( 
        id        INTEGER  NOT  NULL, 
        parent        INTEGER  REFERENCES  directory(id), 
        name        VARCHAR(200), 
        icon        VARCHAR(50), 
        type        INTEGER  REFERENCES  dirent_types(id), 
        url        VARCHAR(200), 
        PRIMARY  KEY(id) 
); 

DROP  INDEX  directory_idx; 

CREATE  UNIQUE  INDEX  directory_idx  ON  directory(parent,  name); 

CREATE  SEQUENCE  dirent_id; 

"CREATE  PROCEDURE  insert_dir_entry 
        (name  VARCHAR,  parent  INTEGER,  type  INTEGER) 
        RETURNS(id  INTEGER) 
BEGIN 
        EXEC  SQL  WHENEVER  SQLERROR  ABORT; 
        EXEC  SEQUENCE  dirent_id.NEXT  INTO  id; 
        EXEC  SQL  PREPARE  c_insert 
                INSERT  INTO  directory 
                        (id,  parent,  type,  name) 
                        VALUES(?,  ?,  ?,  ?); 
        EXEC  SQL  EXECUTE  c_insert  USING  (id,  parent,  type,  name); 
        EXEC  SQL  DROP  c_insert; 
END"; 

CALL  insert_dir_entry('My  Computer',  NULL,  1); 
CALL  insert_dir_entry('Network  Neighbourhood',  NULL,  1); 
CALL  insert_dir_entry('lucifer.guardian.no',  2,  1); 
CALL  insert_dir_entry('rafael.guardian.no',  2,  1); 
CALL  insert_dir_entry('uriel.guardian.no',  2,  1); 
CALL  insert_dir_entry('Control  Panel',  NULL,  1); 
CALL  insert_dir_entry('Services',  6,  1); 
CALL  insert_dir_entry('Apache',  7,  2); 
CALL  insert_dir_entry('Solid  Server  2.2',  7,  2); 

*/ 

function  icon($icon,  $name  =  '',  $width  =  0,  $height  =  0)  { 
        global  $DOCUMENT_ROOT; 
        $icon_loc  =  '/pics/menu'; 
        $file  =  "$DOCUMENT_ROOT$icon_loc/$icon.gif"; 
        if  (!$width  ||  !$height)  { 
        $iconinfo  =  getimagesize($file); 
        if  (!$width)  { 
                $width  =  $iconinfo[0]; 
        } 
        if  (!$height)  { 
                $height  =  $iconinfo[1]; 
        } 
        } 
        printf( '<img%s  border=0  align=top  src="/pics/menu/%s.gif"  '. 
              'width="%d"  height="%d">',  $name  ?  "  name=\"$name\""  :  '', 
              $icon,  $width,  $height); 
} 

/* 
  *  Displays,  recursively,  the  contents  of  a  tree  given  a  starting 
  *  point. 
  * 
  *  Parameters: 
  *      $parent  -  the  parent  node  (not  listed  in  the  directory).    Node 
  *          0  is  the  root  node. 
  * 
  *      $maxdepth  (optional)  -  maximum  number  of  recursion  levels.    -1 
  *          (the  default  value)  means  no  limits. 
  * 
  *      $ancestors  (optional)  -  an  array  of  the  ancestor  nodes  in  the 
  *          current  branch  of  the  tree,  with  the  node  closest  to  the 
  *          top  at  index  0. 
  * 
  *  Global  variables  used: 
  *      $child_nodes 
  *      $node_data 
  *      $last_child 
  * 
  *  Global  variables  modified: 
  *      The  array  pointers  in  $child_nodes  will  be  modified. 
  */ 
function  display_directory($parent,  $showdepth  =  0,  $ancestors  =  false)  { 
        global  $child_nodes,  $node_data,  $last_child; 
        reset($child_nodes[$parent]); 
        $size  =  sizeof($child_nodes[$parent]); 
        $lastindex  =  $size  -  1; 
        if  (!$ancestors)  { 
        $ancestors  =  array(); 
        } 
        $depth  =  sizeof($ancestors); 
        printf( '<div  id="node_%d"  class="dirEntry"  visibility="%s">', 
              $parent,  $showdepth  >  0  ?  'show'  :  'hide'); 
        while  (list($index,  $node)  =  each($child_nodes[$parent]))  { 
        /* 
            For  each  of  the  uptree  nodes: 
            If  an  uptree  node  is  not  the  last  one  on  its  depth 
            of  the  branch,  there  should  be  a  line  instead  of  a  blank 
            before  this  node's  icon. 
          */ 
        for  ($i  =  0;  $i  <  $depth;  $i++)  { 
                $up_parent  =  (int)$node_data[$ancestors[$i]][ 'parent']; 
                $last_node_on_generation  =  $last_child[$up_parent]; 
                $uptree_node_on_generation  =  $ancestors[$i]; 
                if  ($last_node_on_generation  ==  $uptree_node_on_generation)  { 
                icon( "blank"); 
                }  else  { 
                icon( "line"); 
                } 
        } 
        if  ($child_nodes[$node])  {  //  has  children,  i.e.  it  is  a  folder 
                $conn_icon  =  "plus"; 
                $expand  =  true; 
        }  else  { 
                $conn_icon  =  "join"; 
                $expand  =  false; 
        } 
        if  ($index  ==  $lastindex)  { 
                $conn_icon  .=  "bottom"; 
        }  elseif  ($depth  ==  0  &&  $index  ==  0)  { 
                $conn_icon  .=  "top"; 
        } 
        if  ($expand)  { 
                printf( "<a  href=\"javascript:document.layers['node_%d'].visibility='show'\">",  $node); 
        } 
        icon($conn_icon,  "connImg_$node"); 
        if  ($expand)  { 
                print( "</a>"); 
        } 
        $icon  =  $node_data[$node][ 'icon']; 
        if  (!$icon)  { 
                $type  =  $node_data[$node][ 'type']; 
                $icon  =  $GLOBALS[ 'dirent_icons'][$type]; 
        } 
        icon($icon,  "nodeImg_$node"); 

        $name  =  $node_data[$node][ 'name']; 
        printf( '?<font  size="%d">%s</font><br%c>',  -1,  $name,  10); 
        if  ($child_nodes[$node])  { 
                $newdepth  =  $showdepth; 
                if  ($newdepth  >  0)  { 
                $newdepth--; 
                } 
                $new_ancestors  =  $ancestors; 
                $new_ancestors[]  =  $node; 
                display_directory($node,  $newdepth,  $new_ancestors); 
        } 
        } 
        print( "</div\n>"); 
} 

function  setup_directory($parent,  $maxdepth) 
{ 
        global  $dirent_icons,  $child_nodes,  $node_data,  $last_child; 

        $dirent_icons  =  sql_assoc( 'SELECT  id,icon  FROM  dirent_types'); 

        $query  =  'SELECT  id,parent,type,icon,name  '. 
                  'FROM  directory  '. 
                  'ORDER  BY  parent,name'; 

        $child_nodes  =  array(); 
        $node_data  =  array(); 
        $res  =  sql($query); 
        while  (list($id,  $parent,  $type,  $icon,  $name)  =  db_fetch_row($res))  { 
        $child_nodes[(int)$parent][]  =  $id; 
        $node_data[$id]  =  array( 'id'  =>  $id, 
                                'parent'  =>  $parent, 
                                'type'  =>  $type, 
                                'icon'  =>  $icon, 
                                'name'  =>  $name); 
        $last_child[(int)$parent]  =  $id; 
        } 
} 

?>