mv src/{luigi-template,Template}.php

1 files changed, 393 insertions, 0 deletions

diff --git a/php/src/Template.php b/php/src/Template.php
new file mode 100644
index 0000000..69e3fb8
--- /dev/null
+++ b/php/src/Template.php
@@ -0,0 +1,393 @@
+<?php
+declare(strict_types = 1);
+
+namespace Luigi;
+
+const VERSION = '0.4.2';
+
+class Error extends \Exception {};
+
+class UnknownTypeError extends Error {
+  public $type,
+         $name;
+
+  public function __construct(string $type, string $name) {
+    $this->type = $type;
+    $this->name = $name;
+    parent::__construct("unknown $type: $name");
+  }
+};
+
+final class UnknownTemplateError extends UnknownTypeError {
+  public function __construct(string $name) {
+    parent::__construct('template', $name);
+  }
+};
+
+final class UnknownFilterError extends UnknownTypeError {
+  public function __construct(string $name) {
+    parent::__construct('filter', $name);
+  }
+};
+
+final class UnknownKeyError extends UnknownTypeError {
+  public function __construct(string $name) {
+    parent::__construct('key', $name);
+  }
+};
+
+final class MissingFilterParameterError extends Error {
+  public $filter_name;
+
+  public function __construct(string $filter_name) {
+    $this->filter_name = $filter_name;
+    parent::__construct("missing required filter parameter for filter $filter_name");
+  }
+};
+
+final class InvalidTemplateError extends Error {
+  public $template;
+
+  public function __construct(string $template) {
+    $this->template = $template;
+    parent::__construct("invalid template: $template");
+  }
+};
+
+namespace Luigi;
+
+final class RunContext {
+  public $args,
+         $filters;
+
+  public function __construct(array $args, array $filters) {
+    $this->args = $args;
+    $this->filters = $filters;
+  }
+};
+
+final class TemplateFilter {
+  private $name,
+          $args;
+
+  public function __construct(string $name, array $args) {
+    $this->name = $name;
+    $this->args = $args;
+  }
+
+  public function run($v, array &$args, array &$filters) {
+    if (!isset($filters[$this->name])) {
+      throw new UnknownFilterError($this->name);
+    }
+
+    # get callback
+    $cb = $filters[$this->name];
+
+    # invoke callback, return result
+    return $cb($v, $this->args, $args);
+  }
+};
+
+namespace Luigi\Parser;
+
+use Luigi\RunContext;
+use Luigi
+
+abstract class Token {
+  public function run(array $args, array $filters) : string;
+};
+
+final class LiteralToken extends Token {
+  private $val;
+
+  public function __construct(string $val) {
+    $this->val = $val;
+  }
+
+  public function run(array &$args, array &$filters) : string {
+    return $this->val;
+  }
+};
+
+final class FilterToken extends Token {
+  private $key,
+          $filters;
+
+  public function __construct(string $key, array $filters) {
+    $this->key = $key;
+    $this->filters = $filters;
+  }
+
+  public function run(array &$args, array &$filters) : string {
+    if (!isset($args[$this->key])) {
+      throw new UnknownKeyError($this->key);
+    }
+
+    # get initial value
+    $r = $args[$this->key];
+
+    if ($this->filters && count($this->filters) > 0) {
+      # pass value through filters
+      $r = array_reduce($this->filters, function($r, $f) use (&$args, &$filters) {
+        return $f->run($r, $args, $filters);
+      }, $r);
+    }
+
+    # return result
+    return $r;
+  }
+};
+
+const TOKEN_RE = '/
+  # 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';
+
+const FILTER_RE = '/
+  # match filter name
+  (?<name>\S+)
+
+  # match filter arguments (optional)
+  (?<args>(\s*\S+)*)
+
+  # optional trailing whitespace
+  \s*
+/mx';
+
+const DELIM_FILTERS_RE = '/\s*\|\s*/m';
+
+const DELIM_ARGS_RE = '/\s+/m';
+
+function parse_filters(string $filters) : array {
+  # split into individual filters
+  $r = [];
+
+  foreach (preg_split(DELIM_FILTERS_RE, $filters) as $f) {
+    # trim whitespace
+    $f = trim($f);
+
+    # skip empty filters
+    if (!$f)
+      continue;
+
+    # match filter
+    $md = [];
+    if (!preg_match(FILTER_RE, $f, $md)) {
+      throw new UnknownFilterError($f);
+    }
+
+    # add filter to results
+    $r[] = new TemplateFilter($md['name'], (count($md) > 2) ? preg_split(
+      DELIM_ARGS_RE,
+      trim($md['args'])
+    ) : []);
+  }
+
+  # return results
+  return $r;
+}
+
+function parse_template(string $template) : array {
+  # build list of matches
+  $matches = [];
+  $num_matches = preg_match_all(TOKEN_RE, $template, $matches, PREG_SET_ORDER);
+
+  # check for error
+  if ($num_matches === false) {
+    throw new InvalidTemplateError($template);
+  }
+
+  # map matches to tokens
+  return array_map(function($m) {
+    if ($m['key'] !== '') {
+      # filter token
+      return new FilterToken($m['key'], parse_filters($m['filters']));
+    } else {
+      # literal token
+      return new LiteralToken($m['text']);
+    }
+  }, $matches);
+}
+
+namespace Luigi;
+
+public $FILTERS = [
+  'h' => function($s) {
+    return htmlspecialchars($v, ENT_QUOTES);
+  },
+
+  'u' => function($s) {
+    return urlencode($v);
+  },
+
+  'json' => function($v) {
+    return json_encode($v);
+  },
+
+  'hash' => function($v, $args) {
+    if (count($args) !== 1) {
+      throw new MissingFilterParameterError('hash');
+    }
+
+    return hash($args[0], $v);
+  },
+
+  'base64' => function($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($v);
+  },
+
+  'key' => function($v, $args) {
+    if (count($args) !== 1) {
+      throw new MissingFilterParameterError('key');
+    }
+
+    # get key
+    $key = $args[0];
+
+    # make sure key exists
+    if (!isset($v[$key])) {
+      throw new UnknownKeyError($key);
+    }
+
+    # return key
+    return $v[$key];
+  },
+];
+
+final class Template {
+  private $template,
+          $filters,
+          $tokens;
+
+  public function __construct(
+    string $template,
+    array $custom_filters = []
+  ) {
+    global $FILTERS;
+
+    $this->template = $template;
+    $this->filters = count($custom_filters) ? $custom_filters : $FILTERS;
+
+    # parse template into list of tokens
+    $this->tokens = Parser\parse_template($template);
+  }
+
+  public function run(array $args = []) : string {
+    # php sucks
+    $me = $this;
+
+    return join('', array_map(function($token) use ($me, $args) {
+      return $token->run($args, $this->filters);
+    }, $this->tokens));
+  }
+
+  public static function once($str, $args = [], array $filters = []) {
+    $t = new Template($str, $filters);
+    return $t->run($args);
+  }
+};
+
+public function run(
+  string $template,
+  array $args = [],
+  array $filters = []
+) : string {
+  $t = new Template($template, $filters);
+  return $t->run($args);
+}
+
+final class Cache implements \ArrayAccess {
+  private $templates,
+          $filters,
+          $lut = [];
+
+  public function __construct(array $templates, array $filters = []) {
+    $this->templates = $templates;
+    $this->filters = $filters;
+  }
+
+  public function offsetExists($key) : bool {
+    return isset($this->templates[$key]);
+  }
+
+  public function offsetGet($key) {
+    if (isset($this->lut[$key])) {
+      return $this->lut[$key];
+    } else if (isset($this->templates[$key]) {
+      $this->lut[$key] = new Template($this->templates[$key], $this->filters);
+      return $this->lut[$key];
+    } else {
+      throw new UnknownTemplateError($key);
+    }
+  }
+
+  public function offsetUnset($key) {
+    delete($this->lut[$key]);
+    delete($this->templates[$key]);
+  }
+
+  public function offsetSet($key, $val) : bool {
+    delete($this->lut[$key]);
+    $this->templates[$key] = $val;
+    return isset($this->templates[$key]);
+  }
+
+
+  public function run(string $key, array $args = []) : string {
+    return $this->offsetGet($key)->run($args);
+  }
+};