* semantic versioning support for plugins

* add support for defining max myaac version in plugin.json file
* you can now require other plugin to be installed before yours
* added German translation
* fixed faq containing html code

system/libs/semver/Constraint/Constraint.php

@@ -0,0 +1,219 @@
+<?php
+
+/*
+ * This file is part of composer/semver.
+ *
+ * (c) Composer <https://github.com/composer>
+ *
+ * For the full copyright and license information, please view
+ * the LICENSE file that was distributed with this source code.
+ */
+
+namespace Composer\Semver\Constraint;
+
+/**
+ * Defines a constraint.
+ */
+class Constraint implements ConstraintInterface
+{
+    /* operator integer values */
+    const OP_EQ = 0;
+    const OP_LT = 1;
+    const OP_LE = 2;
+    const OP_GT = 3;
+    const OP_GE = 4;
+    const OP_NE = 5;
+
+    /**
+     * Operator to integer translation table.
+     *
+     * @var array
+     */
+    private static $transOpStr = array(
+        '=' => self::OP_EQ,
+        '==' => self::OP_EQ,
+        '<' => self::OP_LT,
+        '<=' => self::OP_LE,
+        '>' => self::OP_GT,
+        '>=' => self::OP_GE,
+        '<>' => self::OP_NE,
+        '!=' => self::OP_NE,
+    );
+
+    /**
+     * Integer to operator translation table.
+     *
+     * @var array
+     */
+    private static $transOpInt = array(
+        self::OP_EQ => '==',
+        self::OP_LT => '<',
+        self::OP_LE => '<=',
+        self::OP_GT => '>',
+        self::OP_GE => '>=',
+        self::OP_NE => '!=',
+    );
+
+    /** @var string */
+    protected $operator;
+
+    /** @var string */
+    protected $version;
+
+    /** @var string */
+    protected $prettyString;
+
+    /**
+     * @param ConstraintInterface $provider
+     *
+     * @return bool
+     */
+    public function matches(ConstraintInterface $provider)
+    {
+        if ($provider instanceof $this) {
+            return $this->matchSpecific($provider);
+        }
+
+        // turn matching around to find a match
+        return $provider->matches($this);
+    }
+
+    /**
+     * @param string $prettyString
+     */
+    public function setPrettyString($prettyString)
+    {
+        $this->prettyString = $prettyString;
+    }
+
+    /**
+     * @return string
+     */
+    public function getPrettyString()
+    {
+        if ($this->prettyString) {
+            return $this->prettyString;
+        }
+
+        return $this->__toString();
+    }
+
+    /**
+     * Get all supported comparison operators.
+     *
+     * @return array
+     */
+    public static function getSupportedOperators()
+    {
+        return array_keys(self::$transOpStr);
+    }
+
+    /**
+     * Sets operator and version to compare with.
+     *
+     * @param string $operator
+     * @param string $version
+     *
+     * @throws \InvalidArgumentException if invalid operator is given.
+     */
+    public function __construct($operator, $version)
+    {
+        if (!isset(self::$transOpStr[$operator])) {
+            throw new \InvalidArgumentException(sprintf(
+                'Invalid operator "%s" given, expected one of: %s',
+                $operator,
+                implode(', ', self::getSupportedOperators())
+            ));
+        }
+
+        $this->operator = self::$transOpStr[$operator];
+        $this->version = $version;
+    }
+
+    /**
+     * @param string $a
+     * @param string $b
+     * @param string $operator
+     * @param bool $compareBranches
+     *
+     * @throws \InvalidArgumentException if invalid operator is given.
+     *
+     * @return bool
+     */
+    public function versionCompare($a, $b, $operator, $compareBranches = false)
+    {
+        if (!isset(self::$transOpStr[$operator])) {
+            throw new \InvalidArgumentException(sprintf(
+                'Invalid operator "%s" given, expected one of: %s',
+                $operator,
+                implode(', ', self::getSupportedOperators())
+            ));
+        }
+
+        $aIsBranch = 'dev-' === substr($a, 0, 4);
+        $bIsBranch = 'dev-' === substr($b, 0, 4);
+
+        if ($aIsBranch && $bIsBranch) {
+            return $operator === '==' && $a === $b;
+        }
+
+        // when branches are not comparable, we make sure dev branches never match anything
+        if (!$compareBranches && ($aIsBranch || $bIsBranch)) {
+            return false;
+        }
+
+        return version_compare($a, $b, $operator);
+    }
+
+    /**
+     * @param Constraint $provider
+     * @param bool $compareBranches
+     *
+     * @return bool
+     */
+    public function matchSpecific(Constraint $provider, $compareBranches = false)
+    {
+        $noEqualOp = str_replace('=', '', self::$transOpInt[$this->operator]);
+        $providerNoEqualOp = str_replace('=', '', self::$transOpInt[$provider->operator]);
+
+        $isEqualOp = self::OP_EQ === $this->operator;
+        $isNonEqualOp = self::OP_NE === $this->operator;
+        $isProviderEqualOp = self::OP_EQ === $provider->operator;
+        $isProviderNonEqualOp = self::OP_NE === $provider->operator;
+
+        // '!=' operator is match when other operator is not '==' operator or version is not match
+        // these kinds of comparisons always have a solution
+        if ($isNonEqualOp || $isProviderNonEqualOp) {
+            return !$isEqualOp && !$isProviderEqualOp
+                || $this->versionCompare($provider->version, $this->version, '!=', $compareBranches);
+        }
+
+        // an example for the condition is <= 2.0 & < 1.0
+        // these kinds of comparisons always have a solution
+        if ($this->operator !== self::OP_EQ && $noEqualOp === $providerNoEqualOp) {
+            return true;
+        }
+
+        if ($this->versionCompare($provider->version, $this->version, self::$transOpInt[$this->operator], $compareBranches)) {
+            // special case, e.g. require >= 1.0 and provide < 1.0
+            // 1.0 >= 1.0 but 1.0 is outside of the provided interval
+            if ($provider->version === $this->version
+                && self::$transOpInt[$provider->operator] === $providerNoEqualOp
+                && self::$transOpInt[$this->operator] !== $noEqualOp) {
+                return false;
+            }
+
+            return true;
+        }
+
+        return false;
+    }
+
+    /**
+     * @return string
+     */
+    public function __toString()
+    {
+        return self::$transOpInt[$this->operator] . ' ' . $this->version;
+    }
+}