From 45cec1489b9fd55ae467e4ba024a4d8ca4972259 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Mystik=20Jon=C3=A1=C5=A1?=
 <martin.jonas@growjob.com>
Date: Wed, 13 Oct 2021 17:56:01 +0200
Subject: [PATCH] Support for complex logic (#18)

---
 docs/README.md                          |  17 ++-
 src/TextTemplate.php                    | 168 +++++++++++++++++++-----
 test/complex-logic.phpt                 | 111 ++++++++++++++++
 test/unit/tpls/16_complex_logic/_in.php |   6 +
 test/unit/tpls/16_complex_logic/_in.txt | 106 +++++++++++++++
 test/unit/tpls/16_complex_logic/out.txt |  35 +++++
 6 files changed, 406 insertions(+), 37 deletions(-)
 create mode 100644 test/complex-logic.phpt
 create mode 100644 test/unit/tpls/16_complex_logic/_in.php
 create mode 100644 test/unit/tpls/16_complex_logic/_in.txt
 create mode 100644 test/unit/tpls/16_complex_logic/out.txt

diff --git a/docs/README.md b/docs/README.md
index abb5fab..91a70c0 100644
--- a/docs/README.md
+++ b/docs/README.md
@@ -134,7 +134,22 @@ Shortcut: Test if a variable is null:
 {/if}
 ```
 
-Limitation: Logical connections like OR / AND are not possible at the moment. Maybe in the future.
+Complex logical expressions can be made using && (and), || (or) and brackets.
+
+```
+{if someVarName && otherVarName}
+    someVarName and otherVarName are set!
+{/if}
+{if someVarName || otherVarName}
+    someVarName or otherVarName are set!
+{/if}
+{if someVarName || (otherVarName && anotherVarName)}
+    Condition is true!
+{/if}
+{if someVarName && !(otherVarName && anotherVarName)}
+    Condition is true!
+{/if}
+```
 
 ## Conditions (else)
 ```
diff --git a/src/TextTemplate.php b/src/TextTemplate.php
index be93d0a..356a1ea 100644
--- a/src/TextTemplate.php
+++ b/src/TextTemplate.php
@@ -421,10 +421,138 @@ private function _getItemValue ($compName, $context, $softFail) {
     }
 
 
-    private function _runIf (&$context, $content, $cmdParam, $softFail, &$ifConditionDidMatch) {
-        //echo $cmdParam;
-        $doIf = false;
+    private function _compareValues($operand1, $operand2, $operator)
+    {
+        switch($operator) {
+            case "==":
+                return ($operand1 == $operand2);
+            case "!=":
+                return ($operand1 != $operand2);
+            case "<":
+                return ($operand1 < $operand2);
+            case ">":
+              return ($operand1 > $operand2);
+            default:
+              throw new TemplateParsingException("Unknown operator: '$operator'");
+        }
+    }
+
+
+    /**
+     * @param $cmdParam
+     * @param $matches
+     * @param $context
+     * @param $softFail
+     * @return bool|string
+     */
+    private function _evaluateCondition($expression, $context, $softFail)
+    {
+      if(!preg_match('/(([\"\']?.*?[\"\']?)\s*(==|<|>|!=)\s*([\"\']?.*[\"\']?)|((!?)\s*(.*)))/i', $expression, $matches)) {
+          throw new TemplateParsingException("Invalid expression: '$expression'");
+      }
+      if(count($matches) == 8) {
+          $comp1 = $this->_getItemValue(trim($matches[7]), $context, $softFail);
+          $operator = '==';
+          $comp2 = $matches[6] ? false : true; // ! prefix
+      } elseif(count($matches) == 5) {
+          $comp1 = $this->_getItemValue(trim($matches[2]), $context, $softFail);
+          $operator = trim($matches[3]);
+          $comp2 = $this->_getItemValue(trim($matches[4]), $context, $softFail);
+      } else {
+          throw new TemplateParsingException("Invalid expression: '$expression'");
+      }
+      return $this->_compareValues($comp1, $comp2, $operator);
+    }
+
+    private function _interpretExpressionValue(&$expressionComponents, &$index, $context, $softFail, $depth = 0) {
+        if($index >= count($expressionComponents)) {
+            throw new TemplateParsingException("Unexpected end of expression.");
+        }
+        $component = $expressionComponents[$index];
+        switch($component) {
+            case "&&":
+            case "||":
+            case ")":
+                throw new TemplateParsingException("Unexpected '$component' instead of value.");
+            case "(":
+                $index++;
+                return $this->_interpretExpression($expressionComponents, $index, $context, $softFail, $depth + 1);
+            case "!(":
+                $index++;
+                return !$this->_interpretExpression($expressionComponents, $index, $context, $softFail, $depth + 1);
+            default:
+                return $this->_evaluateCondition($component, $context, $softFail);
+        }
+    }
+
+    private function _interpretExpression(&$expressionComponents, &$index, $context, $softFail, $depth = 0) {
+        $value = null;
+        while($index < count($expressionComponents)) {
+            $component = $expressionComponents[$index];
+            switch($component) {
+                case "&&":
+                    if($value === null) {
+                        throw new TemplateParsingException("Unexpected '$component'.");
+                    }
+                    $index++;
+                    $value = $this->_interpretExpressionValue($expressionComponents, $index, $context, $softFail, $depth) && $value;
+                    break;
+                case "||":
+                    if($value === null) {
+                        throw new TemplateParsingException("Unexpected '$component'.");
+                    }
+                    $index++;
+                    $value = $this->_interpretExpressionValue($expressionComponents, $index, $context, $softFail, $depth) || $value;
+                    break;
+                case ")":
+                    if($depth == 0) {
+                        throw new TemplateParsingException("Unexpected '$component'. No matching opening '('.");
+                    }
+                    return $value;
+                default:
+                    if($value !== null) {
+                        throw new TemplateParsingException("Unexpected '$component'.");
+                    }
+                    $value = $this->_interpretExpressionValue($expressionComponents, $index, $context, $softFail, $depth);
+            }
+            $index++;
+        }
+        if($depth != 0) {
+            throw new TemplateParsingException("Unmatched '('.");
+        }
+        return $value;
+    }
 
+
+    /**
+     * @param $cmdParam
+     * @param $matches
+     * @param $context
+     * @param $softFail
+     * @return bool|string
+     */
+    private function _evaluateConditionExpression($expression, $context, $softFail)
+    {
+        $expression = preg_replace("/\s+/", " ", $expression);
+        $expression = preg_replace("/!\s+\(/", "!(", $expression);
+        // separators: &&, ||, !(, (, )
+        $expressionComponents = preg_split(
+            "/\s*(&&|\|\||!\(|\(|\))\s*/",
+            $expression,
+            0,
+            PREG_SPLIT_NO_EMPTY | PREG_SPLIT_DELIM_CAPTURE
+        );
+        $index = 0;
+        try {
+            return $this->_interpretExpression($expressionComponents, $index, $context, $softFail);
+        } catch(TemplateParsingException $e) {
+            throw new TemplateParsingException("Error parsing expression '$expression': " . $e->getMessage(), 0, $e);
+        }
+    }
+
+
+    private function _runIf (&$context, $content, $cmdParam, $softFail, &$ifConditionDidMatch)
+    {
         $cmdParam = trim ($cmdParam);
         //echo "\n+ $cmdParam " . strpos($cmdParam, "::NL_ELSE_FALSE");
         // Handle {else}{elseif} constructions
@@ -446,38 +574,7 @@ private function _runIf (&$context, $content, $cmdParam, $softFail, &$ifConditio
             $ifConditionDidMatch = false;
         }
 
-        if ( ! preg_match('/(([\"\']?.*?[\"\']?)\s*(==|<|>|!=)\s*([\"\']?.*[\"\']?)|((!?)\s*(.*)))/i', $cmdParam, $matches)) {
-            return "!! Invalid command sequence: '$cmdParam' !!";
-        }
-        if(count($matches) == 8) {
-          $comp1 = $this->_getItemValue(trim($matches[7]), $context, $softFail);
-          $operator = '==';
-          $comp2 = $matches[6] ? FALSE : TRUE; // ! prefix
-        } elseif(count($matches) == 5){
-          $comp1 = $this->_getItemValue(trim($matches[2]), $context, $softFail);
-          $operator = trim($matches[3]);
-          $comp2 = $this->_getItemValue(trim($matches[4]), $context, $softFail);
-        } else {
-          return "!! Invalid command sequence: '$cmdParam' !!";
-        }
-
-        switch ($operator) {
-            case "==":
-                $doIf = ($comp1 == $comp2);
-                break;
-            case "!=":
-                $doIf = ($comp1 != $comp2);
-                break;
-            case "<":
-                $doIf = ($comp1 < $comp2);
-                break;
-            case ">":
-                $doIf = ($comp1 > $comp2);
-                break;
-
-        }
-
-        if ( ! $doIf) {
+        if ( ! $this->_evaluateConditionExpression($cmdParam, $context, $softFail)) {
             return "";
         }
 
@@ -680,5 +777,4 @@ public function apply ($params, $softFail=TRUE, &$context=[]) {
         return $result;
     }
 
-
 }
\ No newline at end of file
diff --git a/test/complex-logic.phpt b/test/complex-logic.phpt
new file mode 100644
index 0000000..180bc5f
--- /dev/null
+++ b/test/complex-logic.phpt
@@ -0,0 +1,111 @@
+<?php
+namespace Leuffen\TextTemplate;
+
+require __DIR__ . "/../vendor/autoload.php";
+
+
+use Tester\Assert;
+
+
+
+\Tester\Environment::setup();
+
+
+$vars = ["val" => true];
+
+Assert::throws(function() use ($vars) {
+    $in = "{if && val}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '&& val': Unexpected '&&'.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if || val}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '|| val': Unexpected '||'.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if val &&}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression 'val &&': Unexpected end of expression.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if val ||}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression 'val ||': Unexpected end of expression.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if (val}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '(val': Unmatched '('.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if val)}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression 'val)': Unexpected ')'. No matching opening '('.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if !(val}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '!(val': Unmatched '('.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if (val))}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '(val))': Unexpected ')'. No matching opening '('.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if ((val)}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '((val)': Unmatched '('.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if (!(val)}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '(!(val)': Unmatched '('.");
+
+
+Assert::throws(function() use ($vars) {
+    $in = "{if (val) val}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '(val) val': Unexpected 'val'.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if val (val)}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression 'val (val)': Unexpected '('.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if (val) (val)}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression '(val) (val)': Unexpected '('.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if val && &&}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression 'val && &&': Unexpected '&&' instead of value.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if val && ||}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression 'val && ||': Unexpected '||' instead of value.");
+
+Assert::throws(function() use ($vars) {
+    $in = "{if val && )}{/if}";
+    $tt = new TextTemplate($in);
+    $tt->apply($vars, false);
+}, TemplateParsingException::class, "Error parsing expression 'val && )': Unexpected ')' instead of value.");
diff --git a/test/unit/tpls/16_complex_logic/_in.php b/test/unit/tpls/16_complex_logic/_in.php
new file mode 100644
index 0000000..a2d6d5f
--- /dev/null
+++ b/test/unit/tpls/16_complex_logic/_in.php
@@ -0,0 +1,6 @@
+<?php
+
+return [
+    "yes" => true,
+    "no" => false
+];
\ No newline at end of file
diff --git a/test/unit/tpls/16_complex_logic/_in.txt b/test/unit/tpls/16_complex_logic/_in.txt
new file mode 100644
index 0000000..0e4907f
--- /dev/null
+++ b/test/unit/tpls/16_complex_logic/_in.txt
@@ -0,0 +1,106 @@
+{if (yes)}
+(1)=1
+{/if}
+{if (no)}
+(0)=0
+{/if}
+{if !(yes)}
+!(1)=0
+{/if}
+{if !(no)}
+!(0)=1
+{/if}
+
+
+{if yes && yes}
+1&1=1
+{/if}
+{if yes && no}
+1&0=0
+{/if}
+{if no && yes}
+0&1=0
+{/if}
+{if no && no}
+0&0=0
+{/if}
+
+
+{if yes || yes}
+1|1=1
+{/if}
+{if yes || no}
+1|0=1
+{/if}
+{if no || yes}
+0|1=1
+{/if}
+{if no || no}
+0|0=0
+{/if}
+
+
+{if yes && no || yes}
+1&0|1=1
+{/if}
+{if yes && no || no}
+1&0|0=0
+{/if}
+{if no && yes || no}
+0&1|0=0
+{/if}
+{if no && yes || yes}
+0&1|1=1
+{/if}
+
+
+{if yes && (no || yes)}
+1&(0|1)=1
+{/if}
+{if yes && (no || no)}
+1&(0|0)=0
+{/if}
+
+
+{if no || (yes && yes)}
+0|(1&1)=1
+{/if}
+{if no || (no && yes)}
+0|(0&1)=0
+{/if}
+
+
+{if yes && !(no || yes)}
+1&!(0|1)=0
+{/if}
+{if yes && !(no || no)}
+1&!(0|0)=1
+{/if}
+
+
+{if no || !(yes && yes)}
+0|!(1&1)=0
+{/if}
+{if no || !(no && yes)}
+0|!(0&1)=1
+{/if}
+
+
+{if (yes)}
+A
+{/if}
+{if (yes)}
+B
+{/if}
+{if (yes && yes)}
+C
+{/if}
+{if ((yes && yes))}
+D
+{/if}
+{if (((yes) && (yes)))}
+E
+{/if}
+{if (((no) && (yes)) || ((yes) && (yes)))}
+F
+{/if}
diff --git a/test/unit/tpls/16_complex_logic/out.txt b/test/unit/tpls/16_complex_logic/out.txt
new file mode 100644
index 0000000..41fd5d2
--- /dev/null
+++ b/test/unit/tpls/16_complex_logic/out.txt
@@ -0,0 +1,35 @@
+
+(1)=1
+!(0)=1
+
+
+1&1=1
+
+
+1|1=1
+1|0=1
+0|1=1
+
+
+1&0|1=1
+0&1|1=1
+
+
+1&(0|1)=1
+
+
+0|(1&1)=1
+
+
+1&!(0|0)=1
+
+
+0|!(0&1)=1
+
+
+A
+B
+C
+D
+E
+F