Replaced stupid static ResourceUtils class with shiny new ResourceRequest class and corresponding (unfinished) test

4 files changed, 435 insertions, 266 deletions

diff --git a/src/core/resource/ResourceRequest.cpp b/src/core/resource/ResourceRequest.cpp
new file mode 100644
index 0000000..b047082
--- /dev/null
+++ b/src/core/resource/ResourceRequest.cpp
@@ -0,0 +1,238 @@
+/*
+    Ousía
+    Copyright (C) 2014, 2015  Benjamin Paaßen, Andreas Stöckel
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+#include <string>
+
+#include <core/common/Logger.hpp>
+#include <core/common/Rtti.hpp>
+#include <core/common/Utils.hpp>
+#include <core/resource/Resource.hpp>
+#include <core/resource/Resource.hpp>
+#include <core/Registry.hpp>
+
+#include "ResourceRequest.hpp"
+
+namespace ousia {
+
+namespace RttiTypes {
+extern const Rtti Document;
+extern const Rtti Domain;
+extern const Rtti Node;
+extern const Rtti Typesystem;
+}
+
+/**
+ * Map mapping from Rtti pointers to the corresponding ResourceType.
+ */
+static const std::unordered_map<const Rtti *, ResourceType>
+    RTTI_RESOURCE_TYPE_MAP{{&RttiTypes::Document, ResourceType::DOCUMENT},
+                           {&RttiTypes::Domain, ResourceType::DOMAIN_DESC},
+                           {&RttiTypes::Typesystem, ResourceType::TYPESYSTEM}};
+
+/**
+ * Function used internally to build a set with all currently supported
+ * ResourceType instances.
+ *
+ * @param supportedTypes are all supported types.
+ * @return a set containing all ResourceTypes that can be used for these
+ * RTTI descriptors.
+ */
+static const std::unordered_set<ResourceType, Utils::EnumHash>
+supportedResourceTypes(const RttiSet &supportedTypes)
+{
+	std::unordered_set<ResourceType, Utils::EnumHash> res;
+	for (const Rtti *supportedType : supportedTypes) {
+		auto it = RTTI_RESOURCE_TYPE_MAP.find(supportedType);
+		if (it != RTTI_RESOURCE_TYPE_MAP.end()) {
+			res.insert(it->second);
+		}
+	}
+	return res;
+}
+
+/**
+ * Converts a set of supported RTTI descriptors to a string describing the
+ * corresponding ResourceTypes.
+ *
+ * @param supportedTypes are all supported types.
+ * @return a string containing all corresponding resource types.
+ */
+static std::string supportedResourceTypesString(const RttiSet &supportedTypes)
+{
+	return Utils::join(supportedResourceTypes(supportedTypes), ", ", "{", "}");
+}
+
+/**
+ * Tries to deduce the resource type from the given set of supported types.
+ * Returns ResourceType::UNKNOWN if there are ambiguities.
+ *
+ * @param supportedTypes are all supported types.
+ * @return the deduced ResourceType or ResourceType::UNKNOWN if there was an
+ * ambiguity.
+ */
+static ResourceType deduceResourceType(const RttiSet &supportedTypes)
+{
+	ResourceType resourceType = ResourceType::UNKNOWN;
+	for (const Rtti *supportedType : supportedTypes) {
+		auto it = RTTI_RESOURCE_TYPE_MAP.find(supportedType);
+		if (it != RTTI_RESOURCE_TYPE_MAP.end()) {
+			// Preven ambiguity
+			if (resourceType != ResourceType::UNKNOWN &&
+			    resourceType != it->second) {
+				resourceType = ResourceType::UNKNOWN;
+				break;
+			}
+			resourceType = it->second;
+		}
+	}
+	return resourceType;
+}
+
+/**
+ * Function used to limit the supportedTypes to those that correspond to the
+ * ResourceType.
+ *
+ * @param resourceType is the type of the resource type that is going to be
+ * included.
+ * @param supportedTypes are all supported types.
+ * @return a restricted set of supportedTypes that correspond to the
+ * resourceType.
+ */
+static RttiSet limitSupportedTypes(ResourceType resourceType,
+                                   const RttiSet &supportedTypes)
+{
+	// Calculate the expected types
+	RttiSet expectedTypes;
+	for (auto entry : RTTI_RESOURCE_TYPE_MAP) {
+		if (entry.second == resourceType) {
+			expectedTypes.insert(entry.first);
+		}
+	}
+
+	// Restrict the supported types to the expected types
+	return Rtti::setIntersection(supportedTypes, expectedTypes);
+}
+
+/* Class ResourceRequest */
+
+ResourceRequest::ResourceRequest(const std::string &path,
+                                 const std::string &mimetype,
+                                 const std::string &rel,
+                                 const RttiSet &supportedTypes)
+    : path(path),
+      mimetype(mimetype),
+      rel(rel),
+      supportedTypes(supportedTypes),
+      resourceType(ResourceType::UNKNOWN),
+      parser(nullptr)
+{
+}
+
+bool ResourceRequest::deduce(Registry &registry, Logger &logger)
+{
+	bool ok = true;
+
+	// Try to deduce the mimetype if none was given
+	if (mimetype.empty()) {
+		mimetype = registry.getMimetypeForFilename(path);
+		if (mimetype.empty()) {
+			logger.error(std::string("Filename \"") + path +
+			             std::string(
+			                 "\" has an unknown file extension. Explicitly "
+			                 "specify a mimetype."));
+			ok = false;
+		}
+	}
+
+	// Find a parser for the mimetype
+	if (!mimetype.empty()) {
+		auto parserDescr = registry.getParserForMimetype(mimetype);
+		parser = parserDescr.first;
+		parserTypes = parserDescr.second;
+
+		// Make sure a valid parser was returned, and if yes, whether the
+		// parser is allows to run here
+		if (!parser) {
+			logger.error(std::string("Cannot parse files of type \"") +
+			             mimetype + std::string("\""));
+			ok = false;
+		} else if (!Rtti::setIsOneOf(parserTypes, supportedTypes)) {
+			logger.error(std::string("Resource of type \"") + mimetype +
+			             std::string("\" cannot be included here!"));
+			ok = false;
+		}
+	}
+
+	// Limit the supportedTypes to those returned by the parser
+	supportedTypes = Rtti::setIntersection(supportedTypes, parserTypes);
+	if (supportedTypes.empty()) {
+		logger.error(std::string("Cannot include or link a file of type \"") +
+		             mimetype + std::string("\" here!"));
+		ok = false;
+	}
+
+	// Try to deduce the ResourceType from the "rel" string
+	if (!rel.empty()) {
+		resourceType = Resource::getResourceTypeByName(rel);
+		if (resourceType == ResourceType::UNKNOWN) {
+			logger.error(std::string("Unknown relation \"") + rel +
+			             std::string("\", expected one of ") +
+			             supportedResourceTypesString(supportedTypes));
+			ok = false;
+		}
+	}
+
+	// Try to deduce the ResourceType from the supportedTypes
+	if (resourceType == ResourceType::UNKNOWN) {
+		resourceType = deduceResourceType(supportedTypes);
+	}
+
+	// Further limit the supportedTypes to those types that correspond to the
+	// specified resource type.
+	if (resourceType != ResourceType::UNKNOWN) {
+		supportedTypes = limitSupportedTypes(resourceType, supportedTypes);
+		if (supportedTypes.empty()) {
+			logger.error(
+			    std::string("File of type \"") + mimetype +
+			    std::string("\" cannot be included with relationship ") +
+			    Resource::getResourceTypeName(resourceType));
+			ok = false;
+		}
+	} else {
+		// Issue a warning if the resource type is unknown
+		logger.warning(std::string(
+		                   "Ambiguous resource relationship, consider "
+		                   "specifying one of ") +
+		               supportedResourceTypesString(supportedTypes) +
+		               std::string(" as \"rel\" attribute"));
+	}
+
+	return ok;
+}
+
+bool ResourceRequest::locate(Registry &registry, Logger &logger,
+                             Resource &resource,
+                             const Resource &relativeTo) const
+{
+	if (!registry.locateResource(resource, path, resourceType, relativeTo)) {
+		logger.error(std::string("File not found: ") + path);
+		return false;
+	}
+	return true;
+}
+}
+
diff --git a/src/core/resource/ResourceRequest.hpp b/src/core/resource/ResourceRequest.hpp
new file mode 100644
index 0000000..9d5728f
--- /dev/null
+++ b/src/core/resource/ResourceRequest.hpp
@@ -0,0 +1,197 @@
+/*
+    Ousía
+    Copyright (C) 2014, 2015  Benjamin Paaßen, Andreas Stöckel
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file ResourceRequest.hpp
+ *
+ * Defines the ResourceRequest class used by the ResourceManager to deduce as
+ * much information as possible about a resource that was included by the user.
+ *
+ * @author Andreas Stöckel (astoecke@techfak.uni-bielefeld.de)
+ */
+
+#ifndef _OUSIA_RESOURCE_REQUEST_HPP_
+#define _OUSIA_RESOURCE_REQUEST_HPP_
+
+#include <string>
+
+#include <core/common/Rtti.hpp>
+#include <core/resource/Resource.hpp>
+
+namespace ousia {
+
+// Forward declarations
+class Logger;
+class Parser;
+class Registry;
+
+/**
+ * The ResourceRequest class contains user provided data about a Resource that
+ * should be opened and parsed. The ResourceRequest class can then be used to
+ * deduce missing information about the resource and finally to locate the
+ * Resource in the filesystem and to find a parser that is capable of parsing
+ * the Resource.
+ */
+class ResourceRequest {
+private:
+	/**
+	 * Requested path of the file that should be included.
+	 */
+	std::string path;
+
+	/**
+	 * Mimetype of the resource that should be parsed.
+	 */
+	std::string mimetype;
+
+	/**
+	 * Relation string specifing the relationship of the resource within the
+	 * document it is included in.
+	 */
+	std::string rel;
+
+	/**
+	 * Specifies the types of the Node that may result from the resource once it
+	 * has been parsed.
+	 */
+	RttiSet supportedTypes;
+
+	/**
+	 * Types the parser is expected to return.
+	 */
+	RttiSet parserTypes;
+
+	/**
+	 * ResourceType as deduced from the user provided values.
+	 */
+	ResourceType resourceType;
+
+	/**
+	 * Pointer at the Parser instance that may be used to parse the resource.
+	 */
+	Parser *parser;
+
+public:
+	/**
+	 * Constructor of the ResourceRequest class. Takes the user provided data
+	 * about the resource request.
+	 *
+	 * @param path is the requested path of the file that should be included.
+	 * @param mimetype is the mimetype of the resource that should be parsed
+	 * (may be empty, in which case the mimetype is deduced from the file
+	 * extension)
+	 * @param rel is a "relation string" supplied by the user which specifies
+	 * the relationship of the specified resource within the document it is
+	 * included in.
+	 * @param supportedTypes specifies the types of the Node that may result
+	 * from the resource once it has been parsed. This value is not directly
+	 * provided by the user, but by the calling code.
+	 */
+	ResourceRequest(const std::string &path, const std::string &mimetype,
+	                const std::string &rel, const RttiSet &supportedTypes);
+
+	/**
+	 * Tries to deduce all possible information and produces log messages for
+	 * the user.
+	 *
+	 * @param registry from which registered parsers, mimetypes and file
+	 * extensions are looked up.
+	 * @param logger is the logger instance to which errors or warnings are
+	 * logged.
+	 * @return true if a parser has been found that could potentially be used to
+	 * parse the file.
+	 */
+	bool deduce(Registry &registry, Logger &logger);
+
+	/**
+	 * Tries to locate the specified resource.
+	 *
+	 * @param registry from which registered parsers, mimetypes and file
+	 * extensions are looked up.
+	 * @param logger is the logger instance to which errors or warnings are
+	 * logged.
+	 * @param resource is the Resource descriptor that should be filled with the
+	 * actual location.
+	 * @param relativeTo is another resource relative to which the Resource
+	 * should be looked up.
+	 * @return true if a resource was found, false otherwise. Equivalent to
+	 * the value of resource.isValid().
+	 */
+	bool locate(Registry &registry, Logger &logger, Resource &resource,
+	            const Resource &relativeTo = NullResource) const;
+
+	/**
+	 * Returns the requested path of the file that should be included.
+	 *
+	 * @param path given by the user (not the location of an actually found
+	 * resource).
+	 */
+	const std::string &getPath() const { return path; }
+
+	/**
+	 * Returns the mimetype of the resource that should be parsed.
+	 *
+	 * @return the deduced mimetype.
+	 */
+	const std::string &getMimetype() const { return mimetype; }
+
+	/**
+	 * Returns the relation string which specifies the relationship of the
+	 * resource within the document it is included in.
+	 *
+	 * @return the deduced relation string.
+	 */
+	const std::string &getRel() const { return rel; }
+
+	/**
+	 * Returns the types of the Node that may result from the resource once it
+	 * has been parsed. Restricted to the types that may actually returned by
+	 * the parser.
+	 *
+	 * @return the deduced supported types.
+	 */
+	const RttiSet &getSupportedTypes() const { return supportedTypes; }
+
+	/**
+	 * Returns the ResourceType as deduced from the user provided values.
+	 *
+	 * @return deduced ResourceType or ResourceType::UNKNOWN if none could be
+	 * deduced.
+	 */
+	ResourceType getResourceType() const { return resourceType; }
+
+	/**
+	 * Returns the parser that was deduced according to the given resource
+	 * descriptors.
+	 *
+	 * @return the pointer at the parser instance or nullptr if none was found.
+	 */
+	Parser *getParser() const { return parser; }
+
+	/**
+	 * Returns the types the parser may return or an empty set if no parser was
+	 * found.
+	 *
+	 * @return the types the parser may return.
+	 */
+	RttiSet getParserTypes() const { return parserTypes; }
+};
+}
+
+#endif /* _OUSIA_RESOURCE_REQUEST_HPP_ */
+
diff --git a/src/core/resource/ResourceUtils.cpp b/src/core/resource/ResourceUtils.cpp
deleted file mode 100644
index 7c42716..0000000
--- a/src/core/resource/ResourceUtils.cpp
+++ /dev/null
@@ -1,138 +0,0 @@
-/*
-    Ousía
-    Copyright (C) 2014, 2015  Benjamin Paaßen, Andreas Stöckel
-
-    This program is free software: you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation, either version 3 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#include <core/common/Logger.hpp>
-#include <core/common/Rtti.hpp>
-#include <core/common/Utils.hpp>
-
-#include "ResourceUtils.hpp"
-
-namespace ousia {
-
-namespace RttiTypes {
-extern const Rtti Document;
-extern const Rtti Domain;
-extern const Rtti Node;
-extern const Rtti Typesystem;
-}
-
-/**
- * Map mapping from relations (the "rel" attribute in includes) to the
- * corresponding ResourceType.
- */
-static const std::unordered_map<std::string, ResourceType> RelResourceTypeMap{
-    {"document", ResourceType::DOCUMENT},
-    {"domain", ResourceType::DOMAIN_DESC},
-    {"typesystem", ResourceType::TYPESYSTEM}};
-
-/**
- * Map mapping from relations to the corresponding Rtti descriptor.
- */
-static const std::unordered_map<std::string, const Rtti *> RelRttiTypeMap{
-    {"document", &RttiTypes::Document},
-    {"domain", &RttiTypes::Domain},
-    {"typesystem", &RttiTypes::Typesystem}};
-
-/**
- * Map mapping from Rtti pointers to the corresponding ResourceType.
- */
-static const std::unordered_map<const Rtti *, ResourceType> RttiResourceTypeMap{
-    {&RttiTypes::Document, ResourceType::DOCUMENT},
-    {&RttiTypes::Domain, ResourceType::DOMAIN_DESC},
-    {&RttiTypes::Typesystem, ResourceType::TYPESYSTEM}};
-
-ResourceType ResourceUtils::deduceResourceType(const std::string &rel,
-                                               const RttiSet &supportedTypes,
-                                               Logger &logger)
-{
-	ResourceType res;
-
-	// Try to deduce the ResourceType from the "rel" attribute
-	res = deduceResourceType(rel, logger);
-
-	// If this did not work, try to deduce the ResourceType from the
-	// supportedTypes supplied by the Parser instance.
-	if (res == ResourceType::UNKNOWN) {
-		res = deduceResourceType(supportedTypes, logger);
-	}
-	if (res == ResourceType::UNKNOWN) {
-		logger.note(
-		    "Ambigous resource type, consider specifying the \"rel\" "
-		    "attribute");
-	}
-	return res;
-}
-
-ResourceType ResourceUtils::deduceResourceType(const std::string &rel,
-                                               Logger &logger)
-{
-	std::string s = Utils::toLower(rel);
-	if (!s.empty()) {
-		auto it = RelResourceTypeMap.find(s);
-		if (it != RelResourceTypeMap.end()) {
-			return it->second;
-		} else {
-			logger.error(std::string("Unknown relation \"") + rel +
-			             std::string("\""));
-		}
-	}
-	return ResourceType::UNKNOWN;
-}
-
-ResourceType ResourceUtils::deduceResourceType(const RttiSet &supportedTypes,
-                                               Logger &logger)
-{
-	if (supportedTypes.size() == 1U) {
-		auto it = RttiResourceTypeMap.find(*supportedTypes.begin());
-		if (it != RttiResourceTypeMap.end()) {
-			return it->second;
-		}
-	}
-	return ResourceType::UNKNOWN;
-}
-
-const Rtti *ResourceUtils::deduceRttiType(const std::string &rel)
-{
-	std::string s = Utils::toLower(rel);
-	if (!s.empty()) {
-		auto it = RelRttiTypeMap.find(s);
-		if (it != RelRttiTypeMap.end()) {
-			return it->second;
-		}
-	}
-	return &RttiTypes::Node;
-}
-
-RttiSet ResourceUtils::limitRttiTypes(const RttiSet &supportedTypes,
-                                      const std::string &rel)
-{
-	return limitRttiTypes(supportedTypes, deduceRttiType(rel));
-}
-
-RttiSet ResourceUtils::limitRttiTypes(const RttiSet &supportedTypes,
-                                      const Rtti *type)
-{
-	RttiSet res;
-	for (const Rtti *supportedType : supportedTypes) {
-		if (supportedType->isa(*type)) {
-			res.insert(supportedType);
-		}
-	}
-	return res;
-}
-}
diff --git a/src/core/resource/ResourceUtils.hpp b/src/core/resource/ResourceUtils.hpp
deleted file mode 100644
index 13f9251..0000000
--- a/src/core/resource/ResourceUtils.hpp
+++ /dev/null
@@ -1,128 +0,0 @@
-/*
-    Ousía
-    Copyright (C) 2014, 2015  Benjamin Paaßen, Andreas Stöckel
-
-    This program is free software: you can redistribute it and/or modify
-    it under the terms of the GNU General Public License as published by
-    the Free Software Foundation, either version 3 of the License, or
-    (at your option) any later version.
-
-    This program is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU General Public License for more details.
-
-    You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
-
-/**
- * @file ResourceUtils.hpp
- *
- * Contains the ResourceUtils class which defines a set of static utility
- * functions for dealing with Resources and ResourceTypes.
- *
- * @author Andreas Stöckel (astoecke@techfak.uni-bielefeld.de)
- */
-
-#ifndef _OUSIA_RESOURCE_UTILS_HPP_
-#define _OUSIA_RESOURCE_UTILS_HPP_
-
-#include <string>
-
-#include <core/common/Rtti.hpp>
-
-#include "Resource.hpp"
-
-namespace ousia {
-
-/**
- * Class containing static utility functions for dealing with Resources and
- * ResourceTypes.
- */
-class ResourceUtils {
-public:
-	/**
-	 * Function used to deduce the resource type from a given "relation" string
-	 * and a set of RTTI types into which the resource should be converted by a
-	 * parser.
-	 *
-	 * @param rel is a relation string which specifies the type of the resource.
-	 * May be empty.
-	 * @param supportedTypes is a set of RTTI types into which the resource
-	 * should be converted by a parser. Set may be empty.
-	 * @param logger is the Logger instance to which errors should be logged.
-	 * @return a ResourceType specifier.
-	 */
-	static ResourceType deduceResourceType(const std::string &rel,
-	                                       const RttiSet &supportedTypes,
-	                                       Logger &logger);
-
-	/**
-	 * Function used to deduce the resource type from a given "relation" string.
-	 *
-	 * @param rel is a relation string which specifies the type of the resource.
-	 * May be empty.
-	 * @param logger is the Logger instance to which errors should be logged
-	 * (e.g. if the relation string is invalid).
-	 * @return a ResourceType specifier.
-	 */
-	static ResourceType deduceResourceType(const std::string &rel,
-	                                       Logger &logger);
-
-	/**
-	 * Function used to deduce the resource type from a set of RTTI types into
-	 * which the resource should be converted by a parser.
-	 *
-	 * @param supportedTypes is a set of RTTI types into which the resource
-	 * should be converted by a parser. Set may be empty.
-	 * @param logger is the Logger instance to which errors should be logged.
-	 * @return a ResourceType specifier.
-	 */
-	static ResourceType deduceResourceType(const RttiSet &supportedTypes,
-	                                       Logger &logger);
-
-	/**
-	 * Transforms the given relation string to the corresponding RttiType.
-	 *
-	 * @param rel is a relation string which specifies the type of the resource.
-	 * May be empty.
-	 * @return a pointer at the corresponding Rtti instance or a pointer at the
-	 * Rtti descriptor of the Node class (the most general Node type) if the
-	 * given relation type is unknown.
-	 */
-	static const Rtti *deduceRttiType(const std::string &rel);
-
-	/**
-	 * Reduces the number of types supported by a parser as the type of a
-	 * resource to the intersection of the given supported types and the RTTI
-	 * type associated with the given relation string.
-	 *
-	 * @param supportedTypes is a set of RTTI types into which the resource
-	 * should be converted by a parser. Set may be empty.
-	 * @param rel is a relation string which specifies the type of the resource.
-	 * @return the supported type set limited to those types that can actually
-	 * be returned according to the given relation string.
-	 */
-	static RttiSet limitRttiTypes(const RttiSet &supportedTypes,
-	                              const std::string &rel);
-
-	/**
-	 * Reduces the number of types supported by a parser as the type of a
-	 * resource to the intersection of the given supported types and the RTTI
-	 * type associated with the given relation string.
-	 *
-	 * @param supportedTypes is a set of RTTI types into which the resource
-	 * should be converted by a parser. Set may be empty.
-	 * @param type is the type that is to be expected from the parser.
-	 * @return the supported type set limited to those types that can actually
-	 * be returned according to the given relation string (form an isa
-	 * relationship with the given type).
-	 */
-	static RttiSet limitRttiTypes(const RttiSet &supportedTypes,
-	                              const Rtti *type);
-};
-}
-
-#endif /* _OUSIA_RESOURCE_UTILS_HPP_ */
-