Working out scope parsing

.gitignore

@@ -1,5 +1,6 @@
 # Temporary files and dependencies
 test*.php
+*-old.php
 /vendor/
 
 

composer.json

@@ -19,7 +19,8 @@
     },
     "autoload": {
         "psr-4": {
-            "dW\\Highlighter\\": "lib/"
+            "dW\\Highlighter\\": "lib/",
+            "dW\\Highlighter\\Scope\\": "lib/Scope/Matchers/"
         }
     }
 }

lib/Scope/Data.php

@@ -9,7 +9,7 @@ namespace dW\Highlighter\Scope;
 class Data {
     protected string $data;
 
-    protected int $position = 0;
+    protected int $_position = 0;
     protected int $endPosition;
 
     public function __construct(string $data) {
@@ -18,21 +18,21 @@ class Data {
     }
 
     public function consume(int $length = 1): string|bool {
-        if ($this->position === $this->endPosition) {
+        if ($this->_position === $this->endPosition) {
             return false;
         }
 
-        $stop = $this->position + $length;
-        if ($stop >= $this->endPosition) {
+        $stop = $this->_position + $length - 1;
+        if ($stop > $this->endPosition) {
             $stop = $this->endPosition;
         }
 
-        $output = '';
-        for ($i = $this->position; $i <= $stop; $i++) {
-            $output .= $this->data[$this->position++];
+        $result = '';
+        while ($this->_position <= $stop) {
+            $result .= $this->data[$this->_position++];
         }
 
-        return $output;
+        return $result;
     }
 
     public function consumeIf(string $match): string|bool {
@@ -40,11 +40,11 @@ class Data {
     }
 
     public function consumeUntil(string $match, $limit = null): string|bool {
-        if ($this->position === $this->endPosition) {
+        if ($this->_position === $this->endPosition) {
             return false;
         }
 
-        $length = strcspn($this->data, $match, $this->position + 1, $limit);
+        $length = strcspn($this->data, $match, $this->_position, $limit);
         if ($length === 0) {
             return '';
         }
@@ -53,11 +53,11 @@ class Data {
     }
 
     public function consumeWhile(string $match, $limit = null): string|bool {
-        if ($this->position === $this->endPosition) {
+        if ($this->_position === $this->endPosition) {
             return false;
         }
 
-        $length = strspn($this->data, $match, $this->position + 1, $limit);
+        $length = strspn($this->data, $match, $this->_position, $limit);
         if ($length === 0) {
             return '';
         }
@@ -65,29 +65,27 @@ class Data {
         return $this->consume($length);
     }
 
-    public function current(): string|bool {
-        if ($this->position === $this->endPosition) {
-            return false;
-        }
-
-        return $this->data[$this->position];
-    }
-
     public function peek(int $length = 1): string|bool {
-        if ($this->position === $this->endPosition) {
+        if ($this->_position === $this->endPosition) {
             return false;
         }
 
-        $stop = $this->position + $length;
+        $stop = $this->_position + $length - 1;
         if ($stop >= $this->endPosition) {
             $stop = $this->endPosition;
         }
 
         $output = '';
-        for ($i = $this->position; $i <= $stop; $i++) {
+        for ($i = $this->_position; $i <= $stop; $i++) {
             $output .= $this->data[$i];
         }
 
         return $output;
     }
+
+    public function __get(string $name) {
+        if ($name === 'position') {
+            return $this->_position;
+        }
+    }
 }

lib/Scope/Exception.php

@@ -9,11 +9,14 @@ namespace dW\Highlighter\Scope;
 class Exception extends \Exception {
     const MESSAGE = '%s expected; found %s';
 
-    public function __construct(array|string $expected, string $found) {
-        if (is_array($expected)) {
-            $expected = array_map(function($n) {
-                return ($n !== false) ? "\"$n\"" : 'end of input';
-            }, $expected);
+    public function __construct(string $expected, string $found) {
+        $strlen = strlen($expected);
+        if ($strlen > 1) {
+            $temp = [];
+            for ($i = 0; $i < $strlen; $i++) {
+                $temp[] = ($expected[$i] !== false) ? "\"{$expected[$i]}\"" : 'end of input';
+            }
+            $expected = $temp;
 
             if (count($expected) > 2) {
                 $last = array_pop($expected);

lib/Scope/Matcher/PathMatcher.php

@@ -1,11 +0,0 @@
-<?php
-/** @license MIT
- * Copyright 2021 Dustin Wilson et al.
- * See LICENSE and AUTHORS files for details */
-
-declare(strict_types=1);
-namespace dW\Highlighter\Scope\Matcher;
-
-class PathMatcher extends dW\Highlighter\Scope\Matcher {
-    public function __construct(string $prefix, string $first, string $others) {}
-}

lib/Scope/Matcher/ScopeMatcher.php

@@ -1,11 +0,0 @@
-<?php
-/** @license MIT
- * Copyright 2021 Dustin Wilson et al.
- * See LICENSE and AUTHORS files for details */
-
-declare(strict_types=1);
-namespace dW\Highlighter\Scope\Matcher;
-
-class ScopeMatcher extends dW\Highlighter\Scope\Matcher {
-    public function __construct(string $first, string $others) {}
-}

lib/Scope/Matcher/CompositeMatcher.php → lib/Scope/Matchers/CompositeMatcher.php

@@ -4,8 +4,8 @@
  * See LICENSE and AUTHORS files for details */
 
 declare(strict_types=1);
-namespace dW\Highlighter\Scope\Matcher;
+namespace dW\Highlighter\Scope;
 
-class CompositeMatcher extends dW\Highlighter\Scope\Matcher {
+class CompositeMatcher extends Matcher {
     public function __construct(Matcher $left, string $operator, Matcher $right) {}
 }

lib/Scope/Matcher/GroupMatcher.php → lib/Scope/Matchers/GroupMatcher.php

@@ -4,8 +4,8 @@
  * See LICENSE and AUTHORS files for details */
 
 declare(strict_types=1);
-namespace dW\Highlighter\Scope\Matcher;
+namespace dW\Highlighter\Scope;
 
-class GroupMatcher extends dW\Highlighter\Scope\Matcher {
+class GroupMatcher extends Matcher {
     public function __construct(string $prefix, Matcher $selector) {}
 }

lib/Scope/Matcher/NegateMatcher.php → lib/Scope/Matchers/NegateMatcher.php

@@ -4,8 +4,8 @@
  * See LICENSE and AUTHORS files for details */
 
 declare(strict_types=1);
-namespace dW\Highlighter\Scope\Matcher;
+namespace dW\Highlighter\Scope;
 
-class NegateMatcher extends dW\Highlighter\Scope\Matcher {
+class NegateMatcher extends Matcher {
     public function __construct(Matcher $groupOrPath) {}
 }

lib/Scope/Matcher/OrMatcher.php → lib/Scope/Matchers/OrMatcher.php

@@ -4,8 +4,8 @@
  * See LICENSE and AUTHORS files for details */
 
 declare(strict_types=1);
-namespace dW\Highlighter\Scope\Matcher;
+namespace dW\Highlighter\Scope;
 
-class OrMatcher extends dW\Highlighter\Scope\Matcher {
+class OrMatcher extends Matcher {
     public function __construct(Matcher $left, Matcher $right) {}
 }

lib/Scope/Matchers/PathMatcher.php

@@ -0,0 +1,17 @@
+<?php
+/** @license MIT
+ * Copyright 2021 Dustin Wilson et al.
+ * See LICENSE and AUTHORS files for details */
+
+declare(strict_types=1);
+namespace dW\Highlighter\Scope;
+
+class PathMatcher extends Matcher {
+    protected string|null $prefix;
+    protected array $matchers;
+
+    public function __construct(string|null $prefix, Matcher ...$matchers) {
+        $this->prefix = $prefix;
+        $this->matchers = $matchers;
+    }
+}

lib/Scope/Matchers/ScopeMatcher.php

@@ -0,0 +1,15 @@
+<?php
+/** @license MIT
+ * Copyright 2021 Dustin Wilson et al.
+ * See LICENSE and AUTHORS files for details */
+
+declare(strict_types=1);
+namespace dW\Highlighter\Scope;
+
+class ScopeMatcher extends Matcher {
+    protected array $segments;
+
+    public function __construct(SegmentMatcher|TrueMatcher ...$matchers) {
+        $this->segments = $matchers;
+    }
+}

lib/Scope/Matchers/SegmentMatcher.php

@@ -0,0 +1,15 @@
+<?php
+/** @license MIT
+ * Copyright 2021 Dustin Wilson et al.
+ * See LICENSE and AUTHORS files for details */
+
+declare(strict_types=1);
+namespace dW\Highlighter\Scope;
+
+class SegmentMatcher extends Matcher {
+    protected string $segment;
+
+    public function __construct(string $segment) {
+        $this->segment = $segment;
+    }
+}

lib/Scope/Matchers/TrueMatcher.php

@@ -0,0 +1,15 @@
+<?php
+/** @license MIT
+ * Copyright 2021 Dustin Wilson et al.
+ * See LICENSE and AUTHORS files for details */
+
+declare(strict_types=1);
+namespace dW\Highlighter\Scope;
+
+class TrueMatcher extends Matcher {
+    protected string $scopeName;
+
+    public function __construct(string $scopeName) {
+        $this->scopeName = $scopeName;
+    }
+}

lib/Scope/Parser.php

@@ -7,15 +7,20 @@ declare(strict_types=1);
 namespace dW\Highlighter\Scope;
 
 class Parser {
+    public static $debug = false;
+
     protected Data $data;
     protected array $lastExceptionData = [];
 
+    protected static $debugCount = 1;
     protected static Parser $instance;
 
+
     protected function __construct(string $selector) {
         $this->data = new Data($selector);
     }
 
+
     public static function parse(string $selector): Matcher|false {
         self::$instance = new self($selector);
 
@@ -31,21 +36,22 @@ class Parser {
             }
         }
 
-        if (self::$instance->lastExceptionData !== []) {
+        if (self::$debug === true) {
+            echo "------------------------------\n";
+        }
+
+        if ($result === false && self::$instance->lastExceptionData !== []) {
             throw new Exception(self::$instance->lastExceptionData['expected'], self::$instance->lastExceptionData['found']);
         }
 
         return $result;
     }
 
-    protected static function fail(array|string $expected) {
-        self::$instance->lastExceptionData = [
-            'expected' => $expected,
-            'found' => self::$instance->data->peek()
-        ];
-    }
-
     protected static function parseComposite(): Matcher|false {
+        if (self::$debug === true) {
+            self::debug();
+        }
+
         $result = false;
 
         $s1 = self::parseExpression();
@@ -53,14 +59,17 @@ class Parser {
             $s2 = self::parseSpace();
             if ($s2 !== false) {
                 $s3 = self::$instance->data->consumeIf('|&-');
-                if (!in_array($s3, [ '|', '&', '-' ])) {
-                    self::fail([ '|', '&', '-' ]);
-                } else {
+                if ($s3 === '' || $s3 === false) {
+                    $s3 = false;
+                    self::fail('|&-');
+                }
+
+                if ($s3 !== false) {
                     $s4 = self::parseSpace();
                     if ($s4 !== false) {
                         $s5 = self::parseComposite();
                         if ($s5 !== false) {
-                            $result = new Matcher\CompositeMatcher($s1, $s3, $s5);
+                            $result = new CompositeMatcher($s1, $s3, $s5);
                         }
                     }
                 }
@@ -71,84 +80,122 @@ class Parser {
             $result = self::parseExpression();
         }
 
+        if (self::$debug === true) {
+            echo "parseComposite Result: " . var_export($result, true) . "\n";
+        }
+
         return $result;
     }
 
     protected static function parseExpression(): Matcher|false {
+        if (self::$debug === true) {
+            self::debug();
+        }
+
         $result = false;
+
         $s1 = self::$instance->data->consumeIf('-');
-        if ($s1 !== '-') {
+        if ($s1 === '' || $s1 === false) {
+            $s1 = false;
             self::fail('-');
         }
 
-        $s2 = self::parseSpace();
-        if ($s2 !== false) {
-            $s3 = self::parseGroup();
-            if ($s3 !== false) {
-                $s4 = self::parseSpace();
-                if ($s4 !== false) {
-                    $result = new Matcher\NegateMatcher($s3);
+        if ($s1 !== false) {
+            $s2 = self::parseSpace();
+            if ($s2 !== false) {
+                $s3 = self::parseGroup();
+                if ($s3 !== false) {
+                    $s4 = self::parseSpace();
+                    if ($s4 !== false) {
+                        $result = new NegateMatcher($s3);
+                    }
                 }
             }
         }
 
         if ($result === false) {
-            $s1 = self::$instance->data->consumeIf('-', 1);
-            if ($s1 !== '-') {
+            $s1 = self::$instance->data->consumeIf('-');
+            if ($s1 === '' || $s1 === false) {
+                $s1 = false;
                 self::fail('-');
-            } else {
+            }
+
+            if ($s1 !== false) {
                 $s2 = self::parseSpace();
                 if ($s2 !== false) {
                     $s3 = self::parsePath();
                     if ($s3 !== false) {
                         $s4 = self::parseSpace();
                         if ($s4 !== false) {
-                            $result = new Matcher\NegateMatcher($s3);
+                            $result = new NegateMatcher($s3);
                         }
                     }
                 }
             }
-        }
 
-        if ($result === false) {
-            $result = self::parseGroup();
             if ($result === false) {
-                $result = self::parsePath();
+                $result = self::parseGroup();
+                if ($result === false) {
+                    $result = self::parsePath();
+                }
             }
         }
 
+        if (self::$debug === true) {
+            echo "parseExpression Result: " . var_export($result, true) . "\n";
+        }
+
         return $result;
     }
 
     protected static function parseGroup(): Matcher|false {
+        if (self::$debug === true) {
+            self::debug();
+        }
+
         $result = false;
+        $prefix = null;
 
-        $s2 = self::$instance->data->consumeIf('BLR');
-        if (!in_array($s2, [ 'B', 'L', 'R' ])) {
-            self::fail([ 'B', 'L', 'R' ]);
-        } else {
+        $s2 = self::$instance->data->consumeIf('LRB');
+        if ($s2 === '' || $s2 === false) {
+            $s2 = false;
+            self::fail('LRB');
+        }
+
+        if ($s2 !== false) {
             $s3 = self::$instance->data->consumeIf(':');
-            if ($s3 !== ':') {
+            if ($s3 === '' || $s3 === false) {
+                $s3 = false;
                 self::fail(':');
-            } else {
+            }
+
+            if ($s3 !== false) {
                 $prefix = "$s2$s3";
+            }
+        }
 
-                $s2 = self::$instance->data->consumeIf('(');
-                if ($s2 !== '(') {
-                    self::fail('(');
-                } else {
-                    $s3 = self::parseSpace();
-                    if ($s3 !== false) {
-                        $s4 = self::parseSelector();
-                        if ($s4 !== false) {
-                            $s5 = self::parseSpace();
-                            if ($s5 !== false) {
-                                $s6 = self::$instance->data->consumeIf(')');
-                                if ($s6 !== ')') {
-                                    self::fail(')');
-                                } else {
-                                    $result = new GroupMatcher($prefix, $s4);
-                                }
+        if ($prefix !== null) {
+            $s2 = self::$instance->data->consumeIf('(');
+            if ($s2 === '' || $s2 === false) {
+                $s2 = false;
+                self::fail('(');
+            }
+
+            if ($s2 !== false) {
+                $s3 = self::parse();
+                if ($s3 !== false) {
+                    $s4 = self::parseSelector();
+                    if ($s4 !== false) {
+                        $s5 = self::parseSpace();
+                        if ($s5 !== false) {
+                            $s6 = self::$instance->data->consumeIf(')');
+                            if ($s6 === '' || $s6 === false) {
+                                $s6 = false;
+                                self::fail(')');
+                            }
+
+                            if ($s6 !== false) {
+                                $result = new GroupMatcher($prefix, $s4);
                             }
                         }
                     }
@@ -156,114 +203,241 @@ class Parser {
             }
         }
 
+        if (self::$debug === true) {
+            echo "parseGroup Result: " . var_export($result, true) . "\n";
+        }
+
         return $result;
     }
 
     protected static function parsePath(): Matcher|false {
+        if (self::$debug === true) {
+            self::debug();
+        }
+
         $result = false;
+        $prefix = null;
+
+        $s2 = self::$instance->data->consumeIf('LRB');
+        if ($s2 === '' || $s2 === false) {
+            $s2 = false;
+            self::fail('LRB');
+        }
 
-        $s2 = self::$instance->data->consumeIf('BLR');
-        if (!in_array($s2, [ 'B', 'L', 'R' ])) {
-            self::fail([ 'B', 'L', 'R' ]);
-        } else {
+        if ($s2 !== false) {
             $s3 = self::$instance->data->consumeIf(':');
-            if ($s3 !== ':') {
+            if ($s3 === '' || $s3 === false) {
+                $s3 = false;
                 self::fail(':');
-            } else {
+            }
+
+            if ($s3 !== false) {
                 $prefix = "$s2$s3";
+            }
+        }
 
-                $s2 = self::parseScope();
-                if ($s2 !== false) {
-                    $s3 = '';
-                    $s4 = '';
+        $s2 = self::parseScope();
+        if ($s2 !== false) {
+            $s3 = [$s2];
+
+            do {
+                $s4 = false;
+                $s5 = self::parseSpace();
+                if ($s5 !== false) {
+                    $s6 = self::parseScope();
+                    if ($s6 !== false) {
+                        $s3[] = $s6;
+                    }
+                }
+            } while ($s4 !== false);
 
-                    while ($s4 !== false) {
-                        $s3 .= $s4;
-                        $s4 = false;
+            $result = new PathMatcher($prefix, ...$s3);
+        }
 
-                        $s5 = self::parseSpace();
-                        if ($s5 !== false) {
-                            $s6 = self::parseScope();
-                            if ($s6 !== false) {
-                                $s4 = "$s5$s6";
-                            }
-                        }
+        if (self::$debug === true) {
+            echo "parsePath Result: " . var_export($result, true) . "\n";
+        }
+
+        return $result;
+    }
+
+    protected static function parseSegment(): SegmentMatcher|TrueMatcher|false {
+        if (self::$debug === true) {
+            self::debug();
+        }
+
+        $result = false;
+
+        $s1 = self::parseSpace();
+        if ($s1 !== false) {
+            $s2 = self::$instance->data->consumeWhile('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+_');
+            if ($s2 === '' || $s2 === false) {
+                $s2 = false;
+                self::fail('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+_');
+            }
+
+            if ($s2 !== false) {
+                $s3 = self::$instance->data->consumeWhile('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-+_');
+                if ($s3 === '' || $s2 === false) {
+                    $s3 = false;
+                    self::fail('ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-+_');
+                } else {
+                    $s2 .= $s3;
+                }
+            }
+
+            if ($s2 !== false) {
+                $s3 = self::parseSpace();
+                if ($s3 !== false) {
+                    $result = new SegmentMatcher($s2);
+                }
+            }
+
+            if ($result === false) {
+                $s1 = self::parseSpace();
+                if ($s1 !== false) {
+                    $s2 = self::$instance->data->consumeIf('*');
+                    if ($s2 === '' || $s2 === false) {
+                        $s2 = false;
+                        self::fail('*');
                     }
 
-                    if (strlen($s3) > 0) {
-                        $result = new Matcher\PathMatcher($prefix, $s2, $s3);
+                    if ($s2 !== false) {
+                        $s3 = self::parseSpace();
+                        if ($s3 !== false) {
+                            $result = new TrueMatcher($s2);
+                        }
                     }
                 }
             }
         }
 
-        return $result;
-    }
-
-    protected static function parseSpace(): string|false {
-        return self::$instance->data->consumeIf(" \t");
-    }
+        if (self::$debug === true) {
+            echo "parseSegment Result: " . var_export($result, true) . "\n";
+        }
 
-    protected static function parseSegment(): string|false {
-        return false;
+        return $result;
     }
 
     protected static function parseSelector(): Matcher|false {
+        if (self::$debug === true) {
+            self::debug();
+        }
+
         $result = false;
+
         $s1 = self::parseComposite();
         if ($s1 !== false) {
             $s2 = self::parseSpace();
             if ($s2 !== false) {
                 $s3 = self::$instance->data->consumeIf(',');
-                if ($s3 !== ',') {
+                if ($s3 === '' || $s3 === false) {
+                    $s3 = false;
                     self::fail(',');
-                } else {
+                }
+
+                if ($s3 !== false) {
                     $s4 = self::parseSpace();
                     if ($s4 !== false) {
                         $s5 = self::parseSelector();
-                        if ($s5 !== false) {
-                            $result = new Matcher\OrMatcher($s1, $s5);
-                        }
+                        $result = ($s5 === false) ? $s1 : new OrMatcher($s1, $s5);
                     }
                 }
             }
         }
 
-        if ($result === false) {
-            $result = self::parseComposite();
+        if (self::$debug === true) {
+            echo "parseSelector Result: " . var_export($result, true) . "\n";
         }
 
         return $result;
     }
 
-    protected static function parseScope(): string|false {
+    protected static function parseScope(): ScopeMatcher|false {
+        if (self::$debug === true) {
+            self::debug();
+        }
+
         $result = false;
 
         $s1 = self::parseSegment();
         if ($s1 !== false) {
-            $s2 = '';
-            $s3 = '';
-
-            while ($s3 !== false) {
-                $s2 .= $s3;
+            $s2 = [$s1];
+            do {
                 $s3 = false;
 
                 $s4 = self::$instance->data->consumeIf('.');
-                if ($s4 !== '.') {
+                if ($s4 === '' || $s4 === false) {
+                    $s4 = false;
                     self::fail('.');
-                } else {
-                    $s5 = self::parseSegment();
-                    if ($s5 !== false) {
-                        $s3 = "$s4$s5";
+                }
+
+                if ($s4 !== false) {
+                    $s3 = self::parseSegment();
+                    if ($s3 !== false) {
+                        $s2[] = $s3;
                     }
                 }
-            }
+            } while ($s3 !== false);
 
-            if (strlen($s2) > 0) {
-                $result = new Matcher\ScopeMatcher($s1, $s2);
-            }
+            $result = new ScopeMatcher(...$s2);
+        }
+
+        if (self::$debug === true) {
+            echo "parseScope Result: " . var_export($result, true) . "\n";
         }
 
         return $result;
     }
+
+    protected static function parseSpace(): string|false {
+        if (self::$debug === true) {
+            self::debug();
+        }
+
+        $result = self::$instance->data->consumeWhile(" \t");
+        if ($result === false) {
+            self::fail(' \t');
+        }
+
+        if (self::$debug === true) {
+            echo "parseSpace Result: " . var_export($result, true) . "\n";
+        }
+
+        return $result;
+    }
+
+
+    protected static function debug() {
+        $message = <<<DEBUG
+        ------------------------------
+        %s
+        Method: %s
+        Position: %s
+        Char: '%s'
+
+        DEBUG;
+
+        $methodTree = '';
+        $backtrace = debug_backtrace();
+        array_shift($backtrace);
+        array_pop($backtrace);
+        foreach ($backtrace as $b) {
+            $methodTree = "->{$b['function']}$methodTree";
+        }
+
+        printf($message,
+            self::$debugCount++,
+            ltrim($methodTree, '->'),
+            self::$instance->data->position,
+            self::$instance->data->peek()
+        );
+    }
+
+    protected static function fail(string $expected) {
+        self::$instance->lastExceptionData = [
+            'expected' => $expected,
+            'found' => self::$instance->data->peek()
+        ];
+    }
 }