mv template.php luigi-template.php

1 files changed, 370 insertions, 0 deletions

diff --git a/php/luigi-template.php b/php/luigi-template.php
new file mode 100644
index 0000000..cec1ff6
--- /dev/null
+++ b/php/luigi-template.php
@@ -0,0 +1,370 @@
+<?php
+
+namespace Luigi;
+
+const VERSION = '0.4.0';
+
+final class Error extends \Exception {};
+
+final class Filters {
+  private static $filters = null;
+
+  public static function init() {
+    if (self::$filters !== null)
+      return;
+
+    self::$filters = array(
+      'h' => function($s) {
+        return htmlspecialchars($v);
+      },
+
+      'u' => function($s) {
+        return urlencode($v);
+      },
+
+      'json' => function($v) {
+        return json_encode($v);
+      },
+
+      'hash' => function($v, $args) {
+        $algo = (count($args) == 1) ? $args[0] : 'md5';
+        return hash($algo, $v);
+      },
+
+      'base64' => function($v) {
+        return base64_encode($v);
+      },
+
+      'nl2br' => function($v) {
+        return nl2br($v);
+      },
+
+      'uc' => function($v) {
+        return strtoupper($v);
+      },
+
+      'lc' => function($v) {
+        return strtolower($v);
+      },
+
+      'trim' => function($v) {
+        return trim($v);
+      },
+
+      'rtrim' => function($v) {
+        return rtrim($v);
+      },
+
+      'ltrim' => function($v) {
+        return ltrim($v);
+      },
+
+      's' => function($v) {
+        return ($v == 1) ? '' : 's';
+      },
+
+      'strlen' => function($v) {
+        return strlen($v);
+      },
+
+      'count' => function($v) {
+        return count($v);
+      },
+    );
+  }
+
+  public static function get($key) {
+    self::init();
+
+    if (!isset(self::$filters[$key]))
+      throw new Error("unknown filter: $key");
+
+    return self::$filters[$key];
+  }
+
+  public static function add(array $filters) {
+    self::init();
+    self::$filters = array_merge(self::$filters, $filters);
+  }
+};
+
+final class LegacyParser {
+  private static $RES = array(
+    'action' => '/
+      # match opening brace
+      %\{\s*
+
+      # match key
+      ([\w_-]+)
+    
+      # match filter(s)
+      ((\s*\|\s*\w+\s*(\([\w\s,-]+\))?)*)
+
+      # match closing brace
+      \}
+      
+      # or match up all non-% chars or a single % char
+      | ([^%]* | %)
+    /mx',
+
+    'filter' => '/
+      # match filter name
+      ([\w_-]+)
+    
+      # optional trailing whitespace
+      \s*
+    
+      # optional filter arguments
+      (\(([\w\s_,-]+)\))?
+    /mx',
+  );
+
+  public static function parse_template($template) {
+    # build list of matches
+    $matches = array();
+    $num_matches = preg_match_all(
+      self::$RES['action'],
+      $template,
+      $matches,
+      PREG_SET_ORDER
+    );
+  
+    # check for error
+    if ($num_matches === false)
+      throw new Error('error matching template');
+  
+    # walk over matches and build list of actions
+    $r = array_map(function($m) {
+      if ($m[1] !== '') {
+        #  key and filters
+        return array(
+          'type'    => 'action',
+          'key'     => $m[1],
+          'filters' => self::parse_filters($m[2]),
+        );
+      } else {
+        # literal text
+        return array(
+          'type' => 'text',
+          'text' => $m[5],
+        );
+      }
+    }, $matches);
+
+    # return result
+    return $r;
+  }
+
+  public static function parse_filters($filters) {
+    # split into individual filters
+    $r = array();
+    foreach (preg_split('/\s*\|\s*/', $filters) as $f) {
+      # skip empty filters
+      if (!$f)
+        continue;
+
+      # match filter
+      $md = array();
+      if (!preg_match(self::$RES['filter'], $f, $md))
+        throw new Error("invalid filter: $f");
+
+      # add filter to results
+      $r[] = array(
+        # filter name
+        'name' => $md[1],
+
+        # filter arguments
+        'args' => (count($md) > 2) ? preg_split(
+          '/\s*,\s*/', 
+          trim($md[3])
+        ) : array(),
+      );
+    }
+
+    # return results
+    return $r;
+  }
+};
+
+final class Parser {
+  private static $RES = array(
+    'action' => '/
+      # match opening brace
+      %\{
+      
+      # match optional whitespace
+      \s*
+
+      # match key
+      (?<key>[^\s\|\}]+)
+
+      # match filter(s)
+      (?<filters>(\s*\|(\s*[^\s\|\}]+)+)*)
+
+      # match optional whitespace
+      \s*
+    
+      # match closing brace
+      \}
+      
+      # or match up all non-% chars or a single % char
+      | (?<text>[^%]* | %)
+    /mx',
+
+    'filter' => '/
+      # match filter name
+      (?<name>\S+)
+    
+      # match filter arguments (optional)
+      (?<args>(\s*\S+)*)
+    
+      # optional trailing whitespace
+      \s*
+    /mx',
+
+    'delim_filters' => '/\s*\|\s*/m',
+    'delim_args' => '/\s+/m',
+  );
+
+  public static function parse_template($template) {
+    # build list of matches
+    $matches = array();
+    $num_matches = preg_match_all(
+      self::$RES['action'],
+      $template,
+      $matches,
+      PREG_SET_ORDER
+    );
+
+    # check for error
+    if ($num_matches === false)
+      throw new Error("invalid template: $template");
+  
+    # walk over matches and build list of actions
+    $r = array_map(function($m) {
+      if ($m['key'] !== '') {
+        #  key and filters
+        return array(
+          'type'    => 'action',
+          'key'     => $m['key'],
+          'filters' => self::parse_filters($m['filters']),
+        );
+      } else {
+        # literal text
+        return array(
+          'type' => 'text',
+          'text' => $m['text'],
+        );
+      }
+    }, $matches);
+
+    # return result
+    return $r;
+  }
+
+  public static function parse_filters($filters) {
+    # split into individual filters
+    $r = array();
+    foreach (preg_split(self::$RES['delim_filters'], $filters) as $f) {
+      # trim whitespace
+      $f = trim($f);
+
+      # skip empty filters
+      if (!$f)
+        continue;
+
+      # match filter
+      $md = array();
+      if (!preg_match(self::$RES['filter'], $f, $md))
+        throw new Error("invalid filter: $f");
+
+      # add filter to results
+      $r[] = array(
+        # filter name
+        'name' => $md['name'],
+
+        # filter arguments
+        'args' => (count($md) > 2) ? preg_split(
+          self::$RES['delim_args'],
+          trim($md['args'])
+        ) : array(),
+      );
+    }
+
+    # return results
+    return $r;
+  }
+};
+
+final class Template {
+  private $template, $actions, $o;
+
+  public function __construct($template, array $o = array()) {
+    $this->template = $template;
+    $this->o = $o;
+
+    # parse template into list of actions
+    $this->actions = Parser::parse_template($template);
+  }
+
+  public function run(array $args = array()) {
+    # php sucks
+    $me = $this;
+
+    return join('', array_map(function($row) use ($me, $args) {
+      if ($row['type'] == 'text') {
+        # literal text
+        return $row['text'];
+      } else if ($row['type'] == 'action') {
+        # template key (possibly with filters)
+
+        # check value
+        if (!isset($args[$row['key']]))
+          throw new Error("unknown key: {$row['key']}");
+
+        # pass value through filters and return result
+        return array_reduce($row['filters'], function($r, $f) use ($me, $args) {
+          # get filter
+          $fn = Filters::get($f['name']);
+        
+          # call filter and return result
+          return call_user_func($fn, $r, $f['args'], $args, $me);
+        }, $args[$row['key']]);
+      } else {
+        # should never be reached
+        throw new Error("unknown action type: {$row['type']}");
+      }
+    }, $this->actions));
+  }
+
+  public static function run_once($str, array $args = array()) {
+    $t = new Template($str);
+    return $t->run($args);
+  }
+};
+
+final class Cache {
+  private $templates, $o, $lut = array();
+
+  public function __construct(array $templates, array $o = array()) {
+    $this->templates = $templates;
+    $this->o = $o;
+  }
+
+  public function get($key) {
+    if (!isset($this->lut[$key])) {
+      if (!isset($this->templates[$key]))
+        throw new Error("unknown template: $key");
+
+      # lazy-load template
+      $this->lut[$key] = new Template($this->templates[$key], $this->o);
+    }
+
+    # return result
+    return $this->lut[$key];
+  }
+
+  public function run($key, array $args = array()) {
+    return $this->get($key)->run($args);
+  }
+};