1 files changed, 103 insertions, 56 deletions

diff --git a/src/mgui/scrollview.c b/src/mgui/scrollview.c
index a11862f..5cb4773 100644
--- a/src/mgui/scrollview.c
+++ b/src/mgui/scrollview.c
@@ -1,12 +1,14 @@
 #include "../../include/mgui/scrollview.h"
 #include "../../include/mgui/mgui.h"
 #include "../../include/alloc.h"
+#include "../../include/common.h"
 #include <mgl/mgl.h>
 #include <mgl/window/window.h>
 #include <mgl/window/event.h>
 #include <mgl/graphics/rectangle.h>
 #include <limits.h>
 #include <assert.h>
+#include <stdio.h>
 
 #define SCROLL_ACCEL 20.0f
 #define SCROLL_DEACCEL 10.0f
@@ -29,13 +31,17 @@ static float abs_float(float value) {
     return value >= 0.0f ? value : -value;
 }
 
-mgui_scrollview* mgui_scrollview_create() {
+mgui_scrollview* mgui_scrollview_create(void) {
     mgui_scrollview *scrollview = mgui_alloc(sizeof(mgui_scrollview));
     mgui_widget_init(&scrollview->widget, MGUI_WIDGET_SCROLLVIEW);
     scrollview->child = NULL;
     scrollview->position = (mgl_vec2i){ 0, 0 };
     scrollview->scroll = (mgl_vec2i){ 0, 0 };
     scrollview->mouse_scroll = (mgl_vec2f){ 0.0f, 0.0f };
+    scrollview->scrollbar_pos = (mgl_vec2f){ 0.0f, 0.0f };
+    scrollview->scrollbar_size = (mgl_vec2f){ 0.0f, 0.0f };
+    scrollview->scrollbar_move_prev_pos = (mgl_vec2f){ 0.0f, 0.0f };
+    scrollview->moving_scrollbar = false;
     return scrollview;
 }
 
@@ -84,33 +90,77 @@ void mgui_scrollview_on_event(mgui_scrollview *self, mgl_window *window, mgl_eve
     /* TODO: Allow keyboard navigation if scrollview has focus */
     if(event->type == MGL_EVENT_MOUSE_WHEEL_SCROLLED)
         self->mouse_scroll.y += (event->mouse_wheel_scroll.delta * SCROLL_ACCEL);
+    
+    if(event->type == MGL_EVENT_MOUSE_BUTTON_PRESSED
+        && event->mouse_button.button == MGL_BUTTON_LEFT
+        && mgui_rectangle_contains(self->scrollbar_pos, self->scrollbar_size, (mgl_vec2f){ event->mouse_button.x, event->mouse_button.y }))
+    {
+        self->moving_scrollbar = true;
+        self->scrollbar_move_prev_pos = (mgl_vec2f){ event->mouse_button.x, event->mouse_button.y };
+    } else if(event->type == MGL_EVENT_MOUSE_BUTTON_RELEASED && event->mouse_button.button == MGL_BUTTON_LEFT) {
+        self->moving_scrollbar = false;
+    }
 
     if(self->child)
         mgui_widget_on_event(self->child, window, event);
 }
 
-/* TODO: Check if visible in scissor */
+static void mgui_scrollview_handle_scrollbar_move(mgui_scrollview *self, mgl_window *window, double scrollbar_height_ratio) {
+    if(mgl_window_is_mouse_button_pressed(window, MGL_BUTTON_LEFT) && self->moving_scrollbar) {
+        mgl_vec2f mouse_move_diff = (mgl_vec2f){
+            window->cursor_position.x - self->scrollbar_move_prev_pos.x,
+            window->cursor_position.y - self->scrollbar_move_prev_pos.y
+        };
+        self->scrollbar_move_prev_pos.x = window->cursor_position.x;
+        self->scrollbar_move_prev_pos.y = window->cursor_position.y;
 
-void mgui_scrollview_draw(mgui_scrollview *self, mgl_window *window) {
-    const double frame_time = mgui_get_frame_time_seconds();
-    self->mouse_scroll.x *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
-    self->mouse_scroll.y *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
+        /* TODO: Handle vertical scrollbar once its added */
+        /* TODO: Not perfect, improve */
+        if(scrollbar_height_ratio != 0.0)
+            self->scroll.y -= (mouse_move_diff.y * (1.0/scrollbar_height_ratio));
+    }
+}
 
-    if(abs_float(self->mouse_scroll.x) < 0.0001f)
-        self->mouse_scroll.x = 0.0f;
+static void mgui_scrollview_draw_child(mgui_scrollview *self, mgl_window *window, double margin_width, double margin_height, double height, double scrollbar_height, mgl_vec2i child_size) {
+    if(!self->child)
+        return;
 
-    if(abs_float(self->mouse_scroll.y) < 0.0001f)
-        self->mouse_scroll.y = 0.0f;
+    mgl_scissor prev_scissor;
+    mgl_window_get_scissor(window, &prev_scissor);
 
-    self->scroll.x += (int)self->mouse_scroll.x;
-    self->scroll.y += (int)self->mouse_scroll.y;
+    mgl_scissor new_scissor = {
+        .position = self->position,
+        .size = (mgl_vec2i){ self->widget.size.x - margin_width, self->widget.size.y - margin_height }
+    };
+    mgl_window_set_scissor(window, &new_scissor);
 
-    mgl_vec2i child_size;
-    if(self->child)
-        child_size = self->child->size;
-    else
-        child_size = (mgl_vec2i){ 0, 0 };
+    mgui_widget_set_position(self->child,
+        (mgl_vec2i){ self->position.x + self->scroll.x + self->child->margin.left, self->position.y + self->scroll.y + self->child->margin.top });
+    mgui_widget_draw(self->child, window);
+
+    mgl_window_set_scissor(window, &prev_scissor);
+
+    {
+        const double scroll_ratio = child_size.y == 0 ? 0.0 : (double)-self->scroll.y / (double)child_size.y;
+        const int scrollbar_offset_y = height * scroll_ratio;
+
+        const int scrollbar_width = 10;
+        const int right = self->widget.size.x - self->widget.margin.left - self->widget.margin.right;
+
+        self->scrollbar_pos = (mgl_vec2f){ self->position.x + right - scrollbar_width, self->position.y + scrollbar_offset_y };
+        self->scrollbar_size = (mgl_vec2f){ scrollbar_width, scrollbar_height };
+
+        mgl_rectangle rect = {
+            .position = self->scrollbar_pos,
+            .size = self->scrollbar_size,
+            .color = { 55, 60, 68, 255 }
+        };
+
+        mgl_rectangle_draw(mgl_get_context(), &rect);
+    }
+}
 
+static void mgui_scrollview_limit_scroll_to_child_size(mgui_scrollview *self, mgl_vec2i child_size) {
     if(child_size.x > self->widget.size.x) {
         self->scroll.x = min_int(self->scroll.x, 0);
         self->scroll.x = max_int(self->scroll.x, -child_size.x + self->widget.size.x);
@@ -124,46 +174,43 @@ void mgui_scrollview_draw(mgui_scrollview *self, mgl_window *window) {
     } else {
         self->scroll.y = 0;
     }
+}
 
-    if(self->child) {
-        mgl_scissor prev_scissor;
-        mgl_window_get_scissor(window, &prev_scissor);
+static void mgui_scrollview_update_mouse_scroll(mgui_scrollview *self, double frame_time) {
+    self->mouse_scroll.x *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
+    self->mouse_scroll.y *= max_float(0.0f, (1.0f - frame_time * SCROLL_DEACCEL));
+
+    if(abs_float(self->mouse_scroll.x) < 0.0001f)
+        self->mouse_scroll.x = 0.0f;
 
-        /* TODO: Fix all this margin crap, it should be invisible */
-        const int margin_width = self->widget.margin.top + self->widget.margin.bottom;
-        const int margin_height = self->widget.margin.top + self->widget.margin.bottom;
+    if(abs_float(self->mouse_scroll.y) < 0.0001f)
+        self->mouse_scroll.y = 0.0f;
 
-        mgl_scissor new_scissor = {
-            .position = self->position,
-            .size = (mgl_vec2i){ self->widget.size.x - margin_width, self->widget.size.y - margin_height }
-        };
-        mgl_window_set_scissor(window, &new_scissor);
-
-        mgui_widget_set_position(self->child,
-            (mgl_vec2i){ self->position.x + self->scroll.x + self->child->margin.left, self->position.y + self->scroll.y + self->child->margin.top });
-        mgui_widget_draw(self->child, window);
-
-        mgl_window_set_scissor(window, &prev_scissor);
-
-        {
-            /* TODO: Fix all this margin crap, it should be invisible */
-            const int margin_height = self->widget.margin.top + self->widget.margin.bottom;
-            const int height = self->widget.size.y - margin_height;
-            const double scrollbar_height_ratio = child_size.y == 0 ? 0.0 : (double)height / (double)child_size.y;
-            const int scrollbar_height = scrollbar_height_ratio * height;
-
-            const double scroll_ratio = child_size.y == 0 ? 0.0 : (double)-self->scroll.y / (double)child_size.y;
-            const int scrollbar_offset_y = height * scroll_ratio;
-
-            const int scrollbar_width = 5;
-            const int right = self->widget.size.x - self->widget.margin.left - self->widget.margin.right;
-            mgl_rectangle rect = {
-                .position = { self->position.x + right - scrollbar_width, self->position.y + scrollbar_offset_y },
-                .size = { scrollbar_width, scrollbar_height },
-                .color = { 55, 60, 68, 255 }
-            };
-
-            mgl_rectangle_draw(mgl_get_context(), &rect);
-        }
-    }
+    self->scroll.x += (int)self->mouse_scroll.x;
+    self->scroll.y += (int)self->mouse_scroll.y;
+}
+
+/* TODO: Check if visible in scissor */
+void mgui_scrollview_draw(mgui_scrollview *self, mgl_window *window) {
+    const double frame_time = mgui_get_frame_time_seconds();
+    mgui_scrollview_update_mouse_scroll(self, frame_time);
+
+    mgl_vec2i child_size;
+    if(self->child)
+        child_size = self->child->size;
+    else
+        child_size = (mgl_vec2i){ 0, 0 };
+
+    /* TODO: Fix all this margin crap, it should be invisible */
+    const int margin_width = self->widget.margin.top + self->widget.margin.bottom;
+    const int margin_height = self->widget.margin.top + self->widget.margin.bottom;
+
+    /* TODO: Fix all this margin crap, it should be invisible */
+    const int height = self->widget.size.y - margin_height;
+    const double scrollbar_height_ratio = child_size.y == 0 ? 0.0 : (double)height / (double)child_size.y;
+    const int scrollbar_height = scrollbar_height_ratio * height;
+
+    mgui_scrollview_handle_scrollbar_move(self, window, scrollbar_height_ratio);
+    mgui_scrollview_limit_scroll_to_child_size(self, child_size);
+    mgui_scrollview_draw_child(self, window, margin_width, margin_height, height, scrollbar_height, child_size);
 }