Implement text input

4 files changed, 206 insertions, 37 deletions

diff --git a/include/mgl/window/event.h b/include/mgl/window/event.h
index c928d0e..0836098 100644
--- a/include/mgl/window/event.h
+++ b/include/mgl/window/event.h
@@ -3,6 +3,7 @@
 
 #include "key.h"
 #include <stdbool.h>
+#include <stdint.h>
 
 typedef struct mgl_event mgl_event;
 
@@ -12,6 +13,10 @@ typedef struct {
 } mgl_size_event;
 
 typedef struct {
+    uint32_t codepoint;
+} mgl_text_event;
+
+typedef struct {
     int code; /* mgl_key */
     bool alt;
     bool control;
@@ -43,6 +48,7 @@ typedef enum {
     MGL_EVENT_UNKNOWN,
     MGL_EVENT_CLOSED, /* Window closed */
     MGL_EVENT_RESIZED, /* Window resized */
+    MGL_EVENT_TEXT_ENTERED,
     MGL_EVENT_KEY_PRESSED,
     MGL_EVENT_KEY_RELEASED,
     MGL_EVENT_MOUSE_BUTTON_PRESSED,
@@ -54,6 +60,7 @@ struct mgl_event {
     int type; /* mgl_event_type */
     union {
         mgl_size_event size;
+        mgl_text_event text;
         mgl_key_event key;
         mgl_mouse_button_event mouse_button;
         mgl_mouse_move_event mouse_move;
diff --git a/include/mgl/window/window.h b/include/mgl/window/window.h
index cb8baf6..9d7086c 100644
--- a/include/mgl/window/window.h
+++ b/include/mgl/window/window.h
@@ -5,9 +5,8 @@
 #include "../system/vec.h"
 #include <stdbool.h>
 
-/* Vsync is automatically set for windows created, if supported by the system */
+/* Vsync is automatically set for created windows, if supported by the system */
 
-typedef struct __GLXcontextRec *GLXContext;
 typedef struct mgl_event mgl_event;
 /* x11 window handle. TODO: Add others when wayland, etc is added */
 typedef unsigned long mgl_window_handle;
@@ -21,7 +20,7 @@ typedef struct {
 
 struct mgl_window {
     mgl_window_handle window;
-    GLXContext glx_context;
+    void *context;
     mgl_vec2i size;
     /* relative to the top left of the window. only updates when the cursor is inside the window */
     mgl_vec2i cursor_position;
diff --git a/src/window/window.c b/src/window/window.c
index b7f9fd8..cec6417 100644
--- a/src/window/window.c
+++ b/src/window/window.c
@@ -1,10 +1,69 @@
 #include "../../include/mgl/window/window.h"
 #include "../../include/mgl/window/event.h"
 #include "../../include/mgl/mgl.h"
+#include "../../include/mgl/system/utf8.h"
 #include <X11/Xutil.h>
+#include <stdlib.h>
 #include <errno.h>
 #include <stdio.h>
 
+/* Should be in range [2,] */
+#define MAX_STACKED_EVENTS 32
+
+typedef struct {
+    mgl_event stack[MAX_STACKED_EVENTS];
+    int start;
+    int end;
+    int size;
+} x11_events_circular_buffer;
+
+static void x11_events_circular_buffer_init(x11_events_circular_buffer *self) {
+    self->start = 0;
+    self->end = 0;
+    self->size = 0;
+}
+
+static bool x11_events_circular_buffer_append(x11_events_circular_buffer *self, const mgl_event *event) {
+    if(self->size == MAX_STACKED_EVENTS)
+        return false;
+
+    self->stack[self->end] = *event;
+    self->end = (self->end + 1) % MAX_STACKED_EVENTS;
+    ++self->size;
+    return true;
+}
+
+static bool x11_events_circular_buffer_pop(x11_events_circular_buffer *self, mgl_event *event) {
+    if(self->size == 0)
+        return false;
+
+    *event = self->stack[self->start];
+    self->start = (self->start + 1) % MAX_STACKED_EVENTS;
+    --self->size;
+    return true;
+}
+
+typedef struct {
+    GLXContext glx_context;
+    XIM xim;
+    XIC xic;
+    /*
+        Used to stack text event on top of key press/release events and other text events.
+        For example pressing a key should give the user both key press and text events
+        and for IM with multiple characters entered (such as chinese), we want to trigger
+        an event for all of them.
+    */
+    x11_events_circular_buffer events;
+} x11_context;
+
+static bool x11_context_append_event(x11_context *self, const mgl_event *event) {
+    return x11_events_circular_buffer_append(&self->events, event);
+}
+
+static bool x11_context_pop_event(x11_context *self, mgl_event *event) {
+    return x11_events_circular_buffer_pop(&self->events, event);
+}
+
 /* TODO: Use gl OML present for other platforms than nvidia? nvidia doesn't support present yet */
 
 /* TODO: check for glx swap control extension string (GLX_EXT_swap_control, etc) */
@@ -46,21 +105,37 @@ int mgl_window_create(mgl_window *self, const char *title, int width, int height
 
 static int mgl_window_init(mgl_window *self, const char *title, int width, int height, mgl_window_handle parent_window, Window existing_window) {
     self->window = 0;
+    self->context = NULL;
+    self->open = false;
+
+    self->context = malloc(sizeof(x11_context));
+    if(!self->context) {
+        fprintf(stderr, "Failed to allocate x11 context\n");
+        return -1;
+    }
+
+    x11_context *x11_context = self->context;
+    x11_context->glx_context = NULL,
+    x11_context->xim = NULL,
+    x11_context->xic = NULL;
+    x11_events_circular_buffer_init(&x11_context->events);
 
     mgl_context *context = mgl_get_context();
 
     if(parent_window == 0)
         parent_window = DefaultRootWindow(context->connection);
 
-    self->glx_context = context->gl.glXCreateContext(context->connection, context->visual_info, NULL, 1);
-    if(!self->glx_context) {
+    x11_context->glx_context = context->gl.glXCreateContext(context->connection, context->visual_info, NULL, 1);
+    if(!x11_context->glx_context) {
         fprintf(stderr, "glXCreateContext failed\n");
+        mgl_window_deinit(self);
         return -1;
     }
 
     Colormap color_map = XCreateColormap(context->connection, DefaultRootWindow(context->connection), ((XVisualInfo*)context->visual_info)->visual, AllocNone);
     if(!color_map) {
         fprintf(stderr, "XCreateColormap failed\n");
+        mgl_window_deinit(self);
         return -1;
     }
 
@@ -80,6 +155,7 @@ static int mgl_window_init(mgl_window *self, const char *title, int width, int h
             mgl_window_deinit(self);
             return -1;
         }
+
         XFreeColormap(context->connection, color_map);
         self->window = existing_window;
     } else {
@@ -106,7 +182,7 @@ static int mgl_window_init(mgl_window *self, const char *title, int width, int h
     XFlush(context->connection);
 
     /* TODO: Check for failure? */
-    context->gl.glXMakeCurrent(context->connection, self->window, self->glx_context);
+    context->gl.glXMakeCurrent(context->connection, self->window, x11_context->glx_context);
     set_vertical_sync_enabled(self->window, 1);
     context->gl.glEnable(GL_TEXTURE_2D);
     context->gl.glEnable(GL_BLEND);
@@ -126,6 +202,23 @@ static int mgl_window_init(mgl_window *self, const char *title, int width, int h
     XQueryPointer(context->connection, self->window, &dummy_w, &dummy_w, &dummy_i, &dummy_i, &self->cursor_position.x, &self->cursor_position.y, &dummy_u);
 
     mgl_window_on_resize(self, gwa.width, gwa.height);
+
+    x11_context->xim = XOpenIM(context->connection, NULL, NULL, NULL);
+    if(!x11_context->xim) {
+        fprintf(stderr, "XOpenIM failed\n");
+        mgl_window_deinit(self);
+        return -1;
+    }
+
+    x11_context->xic = XCreateIC(x11_context->xim, XNInputStyle, XIMPreeditNothing | XIMStatusNothing, XNClientWindow, self->window, NULL);
+    if(!x11_context->xic) {
+        fprintf(stderr, "XCreateIC failed\n");
+        mgl_window_deinit(self);
+        return -1;
+    }
+
+    XSetICFocus(x11_context->xic);
+
     self->open = true;
     return 0;
 }
@@ -140,14 +233,31 @@ int mgl_window_init_from_existing_window(mgl_window *self, mgl_window_handle exi
 
 void mgl_window_deinit(mgl_window *self) {
     mgl_context *context = mgl_get_context();
-    if(self->glx_context) {
-        context->gl.glXDestroyContext(context->connection, self->glx_context);
-        self->glx_context = NULL;
+    x11_context *x11_context = self->context;
+    if(x11_context) {
+        if(x11_context->xic) {
+            XDestroyIC(x11_context->xic);
+            x11_context->xic = NULL;
+        }
+
+        if(x11_context->xim) {
+            XCloseIM(x11_context->xim);
+            x11_context->xim = NULL;
+        }
+
+        if(x11_context->glx_context) {
+            context->gl.glXDestroyContext(context->connection, x11_context->glx_context);
+            x11_context->glx_context = NULL;
+        }
+
+        free(x11_context);
+        self->context = NULL;
     }
     if(self->window) {
         XDestroyWindow(context->connection, self->window);
         self->window = 0;
     }
+    self->open = false;
 }
 
 static mgl_key x11_keysym_to_mgl_key(KeySym key_sym) {
@@ -207,82 +317,117 @@ static mgl_mouse_button x11_button_to_mgl_button(unsigned int button) {
     return MGL_BUTTON_UNKNOWN;
 }
 
+static void mgl_window_handle_key_event(mgl_window *self, XKeyEvent *xkey, mgl_event *event, mgl_context *context) {
+    event->key.code = x11_keysym_to_mgl_key(XKeycodeToKeysym(context->connection, xkey->keycode, 0));
+    event->key.alt = ((xkey->state & Mod1Mask) != 0);
+    event->key.control = ((xkey->state & ControlMask) != 0);
+    event->key.shift = ((xkey->state & ShiftMask) != 0);
+    event->key.system = ((xkey->state & Mod5Mask) != 0); /* TODO: Fix, doesn't work */
+}
+
+static void mgl_window_handle_text_event(mgl_window *self, XEvent *xev) {
+    /* Ignore silent keys */
+    if(XFilterEvent(xev, None))
+        return;
+
+    x11_context *x11_context = self->context;
+    char buf[128];
+
+    Status status;
+    KeySym ksym;
+    const size_t input_str_len = Xutf8LookupString(x11_context->xic, &xev->xkey, buf, sizeof(buf), &ksym, &status);
+    /* TODO: Handle XBufferOverflow */
+    if(status == XBufferOverflow || input_str_len == 0)
+        return;
+
+    /* TODO: Set XIC location on screen with XSetICValues */
+    if(!mgl_utf8_is_valid((const unsigned char*)buf, input_str_len))
+        return;
+
+    for(size_t i = 0; i < input_str_len;) {
+        uint32_t codepoint = 0;
+        const size_t clen = mgl_utf8_decode((const unsigned char*)&buf[i], &codepoint);
+        i += clen;
+
+        mgl_event text_event;
+        text_event.type = MGL_EVENT_TEXT_ENTERED;
+        text_event.text.codepoint = codepoint;
+        if(!x11_context_append_event(x11_context, &text_event))
+            break;
+    }
+}
+
 /* Returns true if processed */
-static bool mgl_window_on_receive_event(mgl_window *self, XEvent *xev, mgl_event *event, mgl_context *context) {
+static void mgl_window_on_receive_event(mgl_window *self, XEvent *xev, mgl_event *event, mgl_context *context) {
     /* TODO: Handle wm_delete_window event */
     switch(xev->type) {
         case KeyPress: {
             /* TODO: Fill with correct data */
             event->type = MGL_EVENT_KEY_PRESSED;
-            event->key.code = x11_keysym_to_mgl_key(XKeycodeToKeysym(context->connection, xev->xkey.keycode, 0));
-            event->key.alt = ((xev->xkey.state & Mod1Mask) != 0);
-            event->key.control = ((xev->xkey.state & ControlMask) != 0);
-            event->key.shift = ((xev->xkey.state & ShiftMask) != 0);
-            event->key.system = ((xev->xkey.state & Mod5Mask) != 0); /* TODO: Fix, doesn't work */
-            return true;
+            mgl_window_handle_key_event(self, &xev->xkey, event, context);
+            mgl_window_handle_text_event(self, xev);
+            return;
         }
         case KeyRelease: {
             /* TODO: Fill with correct data */
             event->type = MGL_EVENT_KEY_RELEASED;
-            event->key.code = x11_keysym_to_mgl_key(XKeycodeToKeysym(context->connection, xev->xkey.keycode, 0));
-            event->key.alt = ((xev->xkey.state & Mod1Mask) != 0);
-            event->key.control = ((xev->xkey.state & ControlMask) != 0);
-            event->key.shift = ((xev->xkey.state & ShiftMask) != 0);
-            event->key.system = ((xev->xkey.state & Mod5Mask) != 0); /* TODO: Fix, doesn't work */
-            return true;
+            mgl_window_handle_key_event(self, &xev->xkey, event, context);
+            return;
         }
         case ButtonPress: {
             event->type = MGL_EVENT_MOUSE_BUTTON_PRESSED;
             event->mouse_button.button = x11_button_to_mgl_button(xev->xbutton.button);
             event->mouse_button.x = xev->xbutton.x;
             event->mouse_button.y = xev->xbutton.y;
-            return true;
+            return;
         }
         case ButtonRelease: {
             event->type = MGL_EVENT_MOUSE_BUTTON_RELEASED;
             event->mouse_button.button = x11_button_to_mgl_button(xev->xbutton.button);
             event->mouse_button.x = xev->xbutton.x;
             event->mouse_button.y = xev->xbutton.y;
-            return true;
+            return;
         }
         case ConfigureNotify: {
-            while(XCheckTypedWindowEvent(mgl_get_context()->connection, self->window, ConfigureNotify, xev)) {}
+            while(XCheckTypedWindowEvent(context->connection, self->window, ConfigureNotify, xev)) {}
             if(xev->xconfigure.width != self->size.x || xev->xconfigure.height != self->size.x) {
                 mgl_window_on_resize(self, xev->xconfigure.width, xev->xconfigure.height);
 
                 event->type = MGL_EVENT_RESIZED;
                 event->size.width = self->size.x;
                 event->size.height = self->size.y;
-                return true;
+                return;
             }
-            break;
+            event->type = MGL_EVENT_UNKNOWN;
+            return;
         }
         case MotionNotify: {
-            while(XCheckTypedWindowEvent(mgl_get_context()->connection, self->window, MotionNotify, xev)) {}
+            while(XCheckTypedWindowEvent(context->connection, self->window, MotionNotify, xev)) {}
             self->cursor_position.x = xev->xmotion.x;
             self->cursor_position.y = xev->xmotion.y;
 
             event->type = MGL_EVENT_MOUSE_MOVED;
             event->mouse_move.x = self->cursor_position.x;
             event->mouse_move.y = self->cursor_position.y;
-            return true;
+            return;
         }
         case ClientMessage: {
-            mgl_context *context = mgl_get_context();
             if(xev->xclient.format == 32 && (unsigned long)xev->xclient.data.l[0] == context->wm_delete_window_atom) {
                 event->type = MGL_EVENT_CLOSED;
                 self->open = false;
-                return true;
+                return;
             } else if(xev->xclient.format == 32 && (unsigned long)xev->xclient.data.l[0] == context->net_wm_ping_atom) {
                 xev->xclient.window = DefaultRootWindow(context->connection);
                 XSendEvent(context->connection, DefaultRootWindow(context->connection), False, SubstructureNotifyMask | SubstructureRedirectMask, xev);
             }
-            break;
+            event->type = MGL_EVENT_UNKNOWN;
+            return;
+        }
+        default: {
+            event->type = MGL_EVENT_UNKNOWN;
+            return;
         }
     }
-    /*fprintf(stderr, "unhandled event type: %d\n", xev->type);*/
-    event->type = MGL_EVENT_UNKNOWN;
-    return false;
 }
 
 void mgl_window_clear(mgl_window *self, mgl_color color) {
@@ -294,6 +439,11 @@ void mgl_window_clear(mgl_window *self, mgl_color color) {
 bool mgl_window_poll_event(mgl_window *self, mgl_event *event) {
     mgl_context *context = mgl_get_context();
     Display *display = context->connection;
+    x11_context *x11_context = self->context;
+
+    if(x11_context_pop_event(x11_context, event))
+        return true;
+
     if(XPending(display)) {
         XEvent xev; /* TODO: Move to window struct */
         XNextEvent(display, &xev);
diff --git a/tests/main.c b/tests/main.c
index 3ead877..85754f2 100644
--- a/tests/main.c
+++ b/tests/main.c
@@ -51,7 +51,7 @@ static void draw(mgl_window *window, void *userdata) {
         u->fps_counter = 0;
     }
     char str[255];
-    snprintf(str, sizeof(str), "fps: %d", u->fps);
+    snprintf(str, sizeof(str), "hello|world\nfps: %d", u->fps);
 
     mgl_text text;
     mgl_text_init(&text, u->font, str, strlen(str));
@@ -216,7 +216,20 @@ int main(int argc, char **argv) {
     mgl_event event;
     while(mgl_window_is_open(&window)) {
         while(mgl_window_poll_event(&window, &event)) {
-            
+            switch(event.type) {
+                case MGL_EVENT_TEXT_ENTERED: {
+                    fprintf(stderr, "text event, codepoint: %u\n", event.text.codepoint);
+                    break;
+                }
+                case MGL_EVENT_KEY_PRESSED: {
+                    fprintf(stderr, "key press event, code: %u\n", event.key.code);
+                    break;
+                }
+                case MGL_EVENT_KEY_RELEASED: {
+                    fprintf(stderr, "key release event, code: %u\n", event.key.code);
+                    break;
+                }
+            }
         }
 
         mgl_window_clear(&window, (mgl_color){0, 0, 0, 255});