X-Git-Url: https://jasonwoof.com/gitweb/?a=blobdiff_plain;f=template.php;h=03f11ea8635c4f3583809a1e04f80a9f8488c2f5;hb=2afca1009c633e58731dab771e80ad722c399dff;hp=822738b18a45e0a228b6a3106ce41ecb32c98a6c;hpb=d98d81886649a863d0e902f7c4e63b1257217e1f;p=wfpl.git

diff --git a/template.php b/template.php
index 822738b..03f11ea 100644
--- a/template.php
+++ b/template.php
@@ -1,293 +1,307 @@
 <?php
 
-#  Copyright (C) 2005 Jason Woofenden
+#  Copyright (C) 2008,2009 Joshua Grams <josh@qualdan.com>
 #
-#  This file is part of wfpl.
+#  This program is free software: you can redistribute it and/or modify
+#  it under the terms of the GNU General Public License as published by
+#  the Free Software Foundation, either version 3 of the License, or
+#  (at your option) any later version.
+#  
+#  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 program.  If not, see <http://www.gnu.org/licenses/>.
+
+
+# This is a simple template-handling system.  You pass it a big data 
+# structure with key/value pairs, and a template string to fill out.
 #
-#  wfpl is free software; you can redistribute it and/or modify it under the
-#  terms of the GNU Lesser General Public License as published by the Free
-#  Software Foundation; either version 2.1 of the License, or (at your option)
-#  any later version.
+# Within a template, it recognizes tags of the form ~name [arg...]~, 
+# optionally wrapped in HTML comments (which will be removed along with 
+# the tag markers when the template is filled out).
 #
-#  wfpl 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 Lesser General Public License for
-#  more details.
+# { and } as the final argument mark those tags as being the start and 
+# end of a sub-template (for optional or repeated sections).  All other 
+# tags represent slots to be directly filled by data values.  On a } 
+# tag, the name is optional, but must match the corresponding { tag if 
+# present.
 #
-#  You should have received a copy of the GNU Lesser General Public License
-#  along with wfpl; if not, write to the Free Software Foundation, Inc., 51
-#  Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+# For a value tag, arguments represent encodings to be applied 
+# successively.  For instance, ~foo html~ will encode it to be safe in 
+# HTML ('&' to '&amp;', '<' to '&lt;', and so on).
+#
+# { tags can take one argument, which will call the corresponding 
+# tem_auto_* function to munge the data, automating certain common use 
+# cases.  See the comments on the tem_auto functions for more details.
 
+require_once('code/wfpl/encode.php');
+require_once('code/wfpl/file.php');
+require_once('code/wfpl/misc.php');
 
-# This file contains generally useful template handling code. It is wrapped in
-# an object so that if you want/need to you can make more than one instance of
-# it and they won't step on each other's toes. Also there are a set of global
-# functions at the bottom so you don't have to mess around with objects if you
-# don't want to. The documentation will be on the object methods, but just know
-# that each has a straight function wrapper at the bottom with 'tem_' prepended
-# to the name.
 
-# This is designed to be as simple as it can be for your project. The simple
-# way to use it is to set some key/value pairs with tem_set() then call
-# tem_output('filename.html') to output the page. A more complex example
-# including the use of sub-templates can be found in tem_test.php
+# Top-Level Functions
+# -------------------
 
-# FIXME: sub-sub templates need to be cleared when the sub template containing
-# them is run
+function template($template, $data) {
+	return fill_template(parse_template($template), $data);
+}
 
-require_once('code/wfpl/encode.php');
-require_once('code/wfpl/misc.php');
-require_once('code/wfpl/file.php');
+function template_file($filename, $data) {
+	return fill_template(parse_template_file($filename), $data);
+}
 
-class tem {
-	var $keyval;        # an array containing key/value pairs 
-	var $filename;      # template filename (sometimes not set)
-	var $template;      # contents of template
-	var $sub_templates; # tag-name/template-string pairs
-	var $sub_subs;      # key: sub-template name  value: array of names of the sub-templates of this one
-
-	# initialize variables
-	function tem() {
-		$this->keyval = array('' => '~'); # so that ~~ in the template creates a single ~
-		$this->sub_templates = array();
-	}
+function parse_template_file($filename) {
+	return parse_template(file_get_contents($filename));
+}
 
-	# set a key/value pair. if a ~tag~ in the template matches key it will be replaced by value
-	function set($key, $value) {
-		$this->keyval[$key] = $value;
-	}
+# See also parse_template and fill_template.
 
-	# clear a value. Functionally equivalent to set($key, '') but cleaner and more efficient
-	function clear($key) {
-		unset($this->keyval[$key]);
-	}
 
-	# grab a value you stuck in earlier with set()
-	function get($key) {
-		return $this->keyval[$key];
-	}
+# To track our position in the template and in the data, we use a linked 
+# stack structure.  Each node is a hash with a reference to the parent 
+# node along with whatever other data you want to add.  For each stack, 
+# you simply keep a variable with a reference to the top element.  Then 
+# the push and pop operations are:
 
-	# run the template engine on one of the sub-templates and append the result
-	# to the keyval in the main array. See tem_test.php for an example of how
-	# this can be used.
-	function sub($sub_template_name) {
-		$this->keyval[$sub_template_name] .= template_run($this->sub_templates[$sub_template_name], $this->keyval);
+# $top =& tem_push($top);
+# $top =& $top['parent'];
 
-		# after running a sub-template, clear its sub-templates
-		if(isset($this->sub_subs[$sub_template_name])) {
-			foreach($this->sub_subs[$sub_template_name] as $sub_sub) {
-				$this->clear($sub_sub);
-			}
-		}
-	}
-
-	# this is used by tem::load() and should be otherwise useless
-	function _load(&$in, &$out, &$parents, &$parent) {
-		while($in) {
-			# scan for one of: 1) the begining of a sub-template 2) the end of this one 3) the end of the file
-			$n = strpos($in, '<!--~');
-			if($n === false) { # not found
-				# we hit the end of the file
-				$out .= $in;
-				$in = '';
-				return;
-			}
+function &tem_push(&$stack = NULL) {
+	static $refs = array();
 
-			# move everything up to (but not including) <!-- to the output
-			$out .= substr($in, 0, $n);
-			$in = substr($in, $n);
+	# Since a PHP reference is *not* a pointer to data, but a pointer to 
+	# a variable (or array slot), we *have* to first put the new node in
+	# $refs, and then reference it from $new.
 
-			# we found something.
-			# is it an end tag?
-			if(strcmp('<!--~end~-->', substr($in, 0, 12)) == 0) {
-				$in = substr($in, 12);
-				$parent = array_pop($parents);
-				return;
-			}
+	$refs[] = array();
+	$new =& $refs[count($refs)-1];
+	if($stack) $new['parent'] =& $stack;
+	return $new;
+}
 
-			$matches = array();
-			# this limits sub_template names to 50 chars
-			if(ereg('^<!--~([^~]*) start~-->', substr($in, 0, 65), $matches)) {
-				list($start_tag, $tag_name) = $matches;
 
-				# keep track of the tree
-				if(!isset($this->sub_subs[$parent])) {
-					$this->sub_subs[$parent] = array();
+# First we take the template string and convert it into a tree of
+# strings and sub-templates.  A template is a hash with a name string,
+# a pieces array, and possibly an args array.
+
+function parse_template($string) {
+	$tem =& tem_push();
+	$tem['pieces'] = array();
+	# note: for some reason this captures '<!--' but not '-->'.
+	$matches = preg_split("/(<!--)?(~[^~]*~)(?(1)-->)/", $string, -1, PREG_SPLIT_DELIM_CAPTURE);
+	foreach($matches as $match) {
+		if(substr($match,0,1) == '~') {
+			$args = explode(' ', substr($match,1,-1));
+
+			if(count($args) == 1 and $args[0] == '}') $name = '';
+			else $name = array_shift($args);
+
+			if(last($args) == '{') {  # open block
+				array_pop($args);
+				# create a new sub-template
+				# and add it to the parent.
+				$tem =& tem_push($tem);
+				$tem['parent']['pieces'][] =& $tem;
+				$tem['name'] = $name;
+				$tem['pieces'] = array();
+				$tem['args'] = $args;
+			} elseif(last($args) == '}') {  # close block
+				array_pop($args);
+				$cur = $tem['name'];
+				if($name && $name != $cur) {
+				   	die("Invalid template: tried to close '$name', but '$cur' is current.");
 				}
-				array_push($this->sub_subs[$parent], $tag_name);
-				array_push($parents, $parent);
-				$parent = $tag_name;
-
-				$out .= '~' . $tag_name . '~';
-				$in = substr($in, strlen($start_tag));
-				$this->sub_templates[$tag_name] = '';
-				$this->_load($in, $this->sub_templates[$tag_name], $parents, $parent);
-			} else {
-				# it's not a start tag or end tag, so let's pass it through:
-				$out .= substr($in, 0, 5);
-				$in = substr($in, 5);
+				$tem =& $tem['parent'];
+			} else {  # value slot
+				$tem['pieces'][] = array('name' => $name, 'args' => $args);
 			}
-		} #repeat
+		} elseif($match and $match != '<!--') {  # static string
+			$tem['pieces'][] = $match;
+		}
 	}
+	return $tem;
+}
 
-	# like load() except you pass a string instead of a filename
-	function load_str($str) {
-		$this->template = '';
-		$parents = array('top_level_subs' => array());
-		$parent = 'top_level_subs';
-		$this->_load($str, $this->template, $parents, $parent);
+# To fill out a template, we do a depth-first traversal of the template 
+# tree, replacing all tags with the data values.
+
+# The data starts out as a nested set of key/value pairs, where the 
+# values can be:
+
+	# a string to fill a value slot
+	# a hash to fill one instance of a sub-template
+	# an array of hashes to fill multiple instances of a sub-template
+
+# The middle form will be converted to the last form as we use it.
+
+function tem_data_as_rows($value) {
+	if(is_array($value)) {
+		# numeric keys, is already array of arrays -- expand sub-template for each.
+		if(array_key_exists(0, $value)) return $value;
+		# key/value pairs -- expand sub-template once.
+		else return array($value);
+	} elseif($value) {
+		# value -- expand sub-template once using only parent values
+		return array(array());
+	} else {
+		# empty value -- don't expand sub-template
+		return array();
 	}
+}
 
-	# This is useful when you have sub-templates that you want to mess with
-	# before the main template is run. But can also be used to simply specify
-	# the filename ahead of time.
-	function load($filename) {
-		$this->filename = $filename;
-		$this->load_str(read_whole_file($filename));
-	}
-		
-	# Run the template. Pass a filename, or a string, unless you've already
-	# specified a template with load()
-	function run($templ = false) {
-		$template_string = $this->template;
-		$template_file = $this->file;
-		if($templ !== false) {
-			if(strlen($templ) < 150 && file_exists($templ)) {
-				$template_file = $templ;
-				unset($template_string);
-			} else {
-				$template_string = $templ;
-			}
+# To look up a key, we check each namespace (starting with the
+# innermost one) until a value is found.
+
+function tem_find_scope($key, $context) {
+	$scope = $context;
+	do{
+		if(array_key_exists($key, $scope['data'])) {
+			return $scope;
 		}
+	} while($scope = $scope['parent']);
 
-		if(!$template_string) {
-			if(!$template_file) {
-				print "sorry, no template to run\n";
-				exit(1);
-			}
+	# not found; return empty scope.
+	return array('parent' => $context);
+}
 
-			$template_string = read_whole_file($template_file);
-		}
-		
-		return template_run($template_string, $this->keyval);
-	}	
+function tem_get($key, $context) {
+	$scope = tem_find_scope($key, $context);
+	if($scope) return $scope['data'][$key];
+}
 
-	# same as run() except the output is print()ed
-	function output($templ = false) {
-		print($this->run($templ));
+# Return the value for a tag as a set of rows to fill a sub-template.
+# If $tag has an arg, call the tem_auto function to munge the data.
+function &tem_get_rows($tag, $context)
+{
+	$key = $tag['name'];
+	if(count($tag['args'])) {
+		$func = "tem_auto_" . $tag['args'][0];
+		function_exists($func)
+		   	or die("ERROR: template auto function '$func' not found.<br>\n");
 	}
+	$scope = tem_find_scope($key, $context);
 
-	# return the names of the top level subs, or an empty array
-	function top_sub_names() {
-		if(isset($this->sub_subs['top_level_subs'])) {
-			return $this->sub_subs['top_level_subs'];
-		} else {
-			return array();
-		}
-	}
+	if($func) $value = $func($key, $scope);
+	else $value = $scope['data'][$key];
 
-	# return the contents of the top-level sub-templates
-	#
-	# this does not run the sub-templates, so if you've not called tem_sub() on them, they will be blank.
-	#
-	# Return a hash.
-	#     keys: name of top level sub-template.
-	#     values: contents of said sub-template.
-	function top_subs() {
-		$ret = array();
-		$names = $this->top_sub_names();
-		foreach($names as $name) {
-			$ret[$name] = $this->get($name);
-		}
-		return $ret;
-	}
-}
+	$rows = tem_data_as_rows($value);
+	if(is_array($value)) $scope['data'][$key] = $rows;
 
-# Below are functions so you can use the above class without allocating or
-# keeping track of it.
+	return $rows;
+}
 
-# get a reference to the current template object
-function tem_init() { 
-	if(!$GLOBALS['wfpl_template']) {
-		$GLOBALS['wfpl_template'] = new tem();
+# Return the value for a tag as an encoded string.
+function tem_get_enc($tag, $context)
+{
+	$key = $tag['name'];
+	$value = tem_get($key, $context);
+	foreach($tag['args'] as $encoding) {
+		$func = "enc_$encoding";
+		if(function_exists($func)) $value = $func($value, $key);
+		else die("ERROR: encoder function '$func' not found.<br>\n");
 	}
-}
-		
-function tem_set($key, $value) {
-	tem_init();
-	$GLOBALS['wfpl_template']->set($key, $value);
-}
-	
-function tem_get($key) {
-	tem_init();
-	return $GLOBALS['wfpl_template']->get($key);
+	return $value;
 }
 
-function tem_run($templ = false) {
-	tem_init();
-	return $GLOBALS['wfpl_template']->run($templ);
-}
+function fill_template($template, &$data, &$context = NULL) {
+	if(!$context) {
+		$context =& tem_push($context);
+		$context['data'] =& $data;
+	}
 
-function tem_sub($sub_template_name) {
-	tem_init();
-	$GLOBALS['wfpl_template']->sub($sub_template_name);
-}
+	foreach($template['pieces'] as $tem) {
+		if(is_string($tem)) $output .= $tem;
+		elseif($tem['pieces']) {  # sub-template
+			$rows =& tem_get_rows($tem, $context);
+			foreach($rows as $key => &$row) {
+				$context =& tem_push($context);
+				$context['data'] =& $row;
+				$context['rows'] =& $rows;
+					$output .= fill_template($tem, $row, $context);
+				$context =& $context['parent'];
 
-function tem_load($filename) {
-	tem_init();
-	$GLOBALS['wfpl_template']->load($filename);
+			}
+		} else {  # variable
+			$output .= tem_get_enc($tem, $context);
+		}
+	}
+	return $output;
 }
 
-function tem_output($filename = false) {
-	tem_init();
-	$GLOBALS['wfpl_template']->output($filename);
+
+
+# Return a hash containing the top-level sub-templates of tem.
+function top_sub_templates($tem) {
+	$subs = array();
+	foreach($tem['pieces'] as $piece) {
+		if(is_array($piece) and $piece['pieces']) {
+		   	$subs[$piece['name']] = $piece;
+		}
+	}
+	return $subs;
 }
 
+# Replace top-level values in $main with top-level templates from $tem.
+function merge_templates($main, $tem) {
+	$out = array('name' => $main['name'], 'pieces' => array());
 
+	$subs = top_sub_templates($tem);
 
-# this is used in template_run() and should be of no other use
-function template_filler($matches) {
-	list($tag, $enc) = explode('.', $matches[1], 2);
-	$value = $GLOBALS['wfpl_template_keyval'][$tag];
-	if($enc) {
-		$encs = explode('.', $enc);
-		foreach($encs as $enc) {
-			$enc = "enc_$enc";
-			if(function_exists($enc)) {
-				$value = $enc($value, $tag);
-			} else {
-				print "ERROR: encoder function '$enc' not found.<br>\n";
-				exit(1);
-			}
+	foreach($main['pieces'] as $piece) {
+		if(is_array($piece) and !$piece['pieces'] and $subs[$piece['name']]) {
+			$piece = $subs[$piece['name']];
 		}
+		$out['pieces'][] = $piece;
 	}
-	return $value;
+	return $out;
 }
 
 
-# pass a template string and an associative array of the key/values and it
-# returns the result.
-function template_run($template, &$keyval) {
-	$GLOBALS['wfpl_template_keyval'] =& $keyval;
-	return preg_replace_callback(array('|<!--~([^~]*)~-->|', '|~([^~]*)~|', '|<span class="template">([^<]*)</span>|', '|<p class="template">([^<]*)</p>|'), 'template_filler', $template);
-}
 
-function tem_top_sub_names() {
-	tem_init();
-	return $GLOBALS['wfpl_template']->top_sub_names();
+# tem_auto functions
+# ------------------
+#
+# If a { tag has an argument, the corresponding tem_auto function is called.
+# This allows it to mangle the data to automate some common cases.
+
+# 'sep' (separator) sections will be shown for all but the last parent row.
+# Sample usage:
+# 	<!--~rows~-->
+# 		<!--~row~-->
+# 			row content...
+# 			<!--~separator sep {~--><hr><!--~separator }"-->
+# 		<!--~row~-->
+# 	<!--~rows~-->
+#
+function tem_auto_sep($key, $context) {
+	$rows =& $context['parent']['rows'];
+	if(key($rows)) return true;
+	# else we are on the last row (cursor has hit the end and reset).
 }
 
-function tem_top_subs() {
-	tem_init();
-	return $GLOBALS['wfpl_template']->top_subs();
+# 'once' sections will be shown once unless the corresponding data value
+# is false.  We check only for false; 0 or '' will not work.
+
+function tem_auto_once($key, $context) {
+	if($context['data'][$key] !== false)
+	   	return tem_data_as_rows(true);
 }
 
-# replaces currently set template, and returns the old.
-function tem_load_new($file) {
-	$old = $GLOBALS['wfpl_template'];
-	$GLOBALS['wfpl_template'] = new tem();
-	$GLOBALS['wfpl_template']->load($file);
-	return $old;
+# 'evenodd' sections are given an 'evenodd' attribute whose value
+# alternates between 'even' and 'odd'.
+
+function tem_auto_evenodd($key, $context) {
+	$rows = $context['data'][$key];
+	$even = 0;
+	$text = array('even', 'odd');
+	foreach($rows as $key => $value) {
+		$rows[$key]['evenodd'] = $text[$even];
+		$even = 1 - $even;
+	}
+	return tem_data_as_rows($rows);
 }
 
 ?>