ProcessManager: Rename it to SystemMonitor

This is a more appropriate name now that it does a lot
more than just manage processes ^)

Applications/SystemMonitor/ProcessModel.h

@@ -0,0 +1,68 @@
+#pragma once
+
+#include <AK/AKString.h>
+#include <AK/HashMap.h>
+#include <AK/Vector.h>
+#include <LibGUI/GModel.h>
+#include <unistd.h>
+
+class GraphWidget;
+
+class ProcessModel final : public GModel {
+public:
+    enum Column {
+        Icon = 0,
+        Name,
+        CPU,
+        State,
+        Priority,
+        User,
+        PID,
+        Virtual,
+        Physical,
+        Syscalls,
+        __Count
+    };
+
+    static NonnullRefPtr<ProcessModel> create(GraphWidget& graph) { return adopt(*new ProcessModel(graph)); }
+    virtual ~ProcessModel() override;
+
+    virtual int row_count(const GModelIndex&) const override;
+    virtual int column_count(const GModelIndex&) const override;
+    virtual String column_name(int column) const override;
+    virtual ColumnMetadata column_metadata(int column) const override;
+    virtual GVariant data(const GModelIndex&, Role = Role::Display) const override;
+    virtual void update() override;
+
+private:
+    explicit ProcessModel(GraphWidget&);
+
+    GraphWidget& m_graph;
+
+    struct ProcessState {
+        pid_t pid;
+        unsigned times_scheduled;
+        String name;
+        String state;
+        String user;
+        String priority;
+        size_t amount_virtual;
+        size_t amount_resident;
+        unsigned syscall_count;
+        float cpu_percent;
+        int icon_id;
+    };
+
+    struct Process {
+        ProcessState current_state;
+        ProcessState previous_state;
+    };
+
+    HashMap<uid_t, String> m_usernames;
+    HashMap<pid_t, NonnullOwnPtr<Process>> m_processes;
+    Vector<pid_t> m_pids;
+    RefPtr<GraphicsBitmap> m_generic_process_icon;
+    RefPtr<GraphicsBitmap> m_high_priority_icon;
+    RefPtr<GraphicsBitmap> m_low_priority_icon;
+    RefPtr<GraphicsBitmap> m_normal_priority_icon;
+};