[ADD/WIP] Push all the Janet changes

This is still unstable(and I still need to design/document the exposed
API)! Do(n't) go and use it!

src/include/Extension.h

@@ -0,0 +1,81 @@
+#ifndef PARSEE_EXTENSION_H
+#define PARSEE_EXTENSION_H
+
+#include <stdbool.h>
+
+#include <Cytoplasm/Json.h>
+
+#include <XML.h>
+
+typedef struct ParseeData ParseeData;
+
+typedef struct Extensions Extensions;
+typedef struct Extension Extension;
+
+typedef enum StanzaType {
+    STANZA_RAW          = 0,
+    STANZA_MESSAGE      = 1,
+    STANZA_IQ           = 2,
+    STANZA_PRESENCE     = 3,
+
+    STANZA_TYPE_COUNT
+} StanzaType;
+
+/** Verifies if extensions are enabled with the Parsee binary.
+ * Functions here <strong>WILL</strong> fail if this function 
+ * returns false!
+ * -------------------
+ * Returns: true IFF extensions are enabled */
+extern bool ExtensionEnabled(void);
+
+/* Creates an extension context. */
+extern Extensions * ExtensionCreateContext(struct ParseeData *data);
+
+/** Destroys the entire extension context, and all of its extensions.
+ * -------------------------------------
+ * Returns: NOTHING
+ * Thrashes: ctx */
+extern void ExtensionDestroyContext(Extensions *ctx);
+
+/** Loads a basic extension from a simple Janet file.
+ * ---------------------------- 
+ * Returns: An extension handle[ctx] | NULL */
+extern Extension * ExtensionLoadBasic(Extensions *ctx, char *id, char *file);
+
+/** Reloads an extension from an ID.
+ * ---------------------------
+ * Returns: NOTHING */
+extern void ExtensionReload(Extensions *ctx, char *id);
+
+/** Loads extensions from a directory. The directory's Janet files are loaded 
+ * (with the part before the .janet extension denoting the identifier).
+ * -----------------------------------
+ * Returns: NOTHING */
+extern void ExtensionLoadDir(Extensions *ctx, char *dir);
+
+/** Broadcasts a stanza received to all extensions(by calling the 
+ * on-stanza function).
+ * -----------------------------------------
+ * Returns: NOTHING
+ * Modifies: the extensions */
+extern bool ExtensionPushStanza(Extensions *ctx, XMLElement *stanza, StanzaType t);
+
+/** Broadcasts a Matrix event to all extensions, akin to ExtensionPushStanza.
+ * -----------
+ * Returns: NOTHING
+ * Modifies: the extensions */
+extern bool ExtensionPushEvent(Extensions *ctx, HashMap *obj);
+
+/** Calls "on-xmpp-cmd" on extensions' Janet side, with no arguments.
+ * ----------
+ * Returns: NOTHING
+ * Modifies: the extensions */
+extern void ExtensionRequestCommands(Extensions *ctx);
+
+extern void 
+ExtensionShoveCommands(Extensions *ctx, char *jid, XMLElement *query, XMLElement *stanza);
+
+extern void 
+ExtensionManageCommands(Extensions *ctx, XMLElement *stanza);
+
+#endif