feat: Greatly improved diff view

Fixes #631

plugins/builtin/include/content/views/view_diff.hpp

@@ -4,11 +4,16 @@
 
 #include <imgui.h>
 #include <hex/ui/view.hpp>
+#include <hex/api/task.hpp>
 
 #include <array>
 #include <string>
 #include <vector>
 
+#include "ui/hex_editor.hpp"
+
+#include <IntervalTree.h>
+
 namespace hex::plugin::builtin {
 
     class ViewDiff : public View {
@@ -19,13 +24,33 @@ namespace hex::plugin::builtin {
         void drawContent() override;
 
     private:
-        void drawDiffLine(const std::array<int, 2> &providerIds, u64 row) const;
+        struct Column {
+            ui::HexEditor hexEditor;
+            int provider = -1;
+            i32 scrollLock = 0;
+        };
 
-        int m_providerA = -1, m_providerB = -1;
+        enum class DifferenceType : u8 {
+            Added,
+            Removed,
+            Modified
+        };
 
-        bool m_greyedOutZeros = true;
-        bool m_upperCaseHex   = true;
-        u32 m_columnCount     = 16;
+        struct Diff {
+            Region region;
+            DifferenceType type;
+        };
+
+        bool drawDiffColumn(Column &column, float height) const;
+        void drawProviderSelector(Column &column);
+        std::string getProviderName(Column &column) const;
+
+    private:
+        std::array<Column, 2> m_columns;
+
+        std::vector<Diff> m_diffs;
+        TaskHolder m_diffTask;
+        std::atomic<bool> m_analyzed = false;
     };
 
 }