#include "alfpriv.h"

TCHAR *_alf_panelClass = NULL;

typedef struct {
    ALFLayout layout;
    const ALFPanelVTable *vtbl;
    void *closure;
} ALFPanelPriv;

static void
ALF_Panel_IntializePriv(ALFPanelPriv *priv)
{
    ALF_Layout_Init(&priv->layout);
}

static void
ALF_Panel_ClearPriv(ALFPanelPriv *priv)
{
    ALF_Layout_Clear(&priv->layout);
}

static void
ALF_Panel_InternalDefPaint(ALFPanelPriv *priv, HWND hwnd, HDC dc, RECT *r)
{
    if (priv->layout.bgcolor == ALF_COLOR_TRANSPARENT) {
        ALF_Compat_DrawThemeParentBackground(hwnd, dc, r);
    } else {
        ALF_FillRect(dc, r, priv->layout.bgcolor);
    }
}


void
ALF_Panel_DefPaint(HWND panel, HDC hDC, RECT *rcPaint)
{
    ALFPanelPriv *priv = (ALFPanelPriv*)GetWindowLongPtr(panel, 0);
    ALF_Panel_InternalDefPaint(priv, panel, hDC, rcPaint);
}

static void
ALF_Panel_Paint(ALFPanelPriv *priv, HWND hwnd, HDC dc, RECT *r)
{
    if (priv->vtbl && priv->vtbl->paint) {
        priv->vtbl->paint(priv->closure, hwnd, dc, r);
    } else {
        ALF_Panel_InternalDefPaint(priv, hwnd, dc, r);
    }
}

void
ALF_Panel_SetVTable(HWND panel, const ALFPanelVTable *vtbl, void *closure)
{
    ALFPanelSetVtblParams p = { vtbl, closure };
    SendMessage(panel, ALF_WM_PANEL_SETVTABLE, 0, (LPARAM)&p);
}

LRESULT
ALF_Panel_DefWindowProc(HWND window, UINT msg, WPARAM wparam, LPARAM lparam)
{
    ALFPanelPriv *priv = (ALFPanelPriv *)GetWindowLongPtr(window, 0);

    if (msg == WM_DESTROY) {
        if (priv->vtbl && priv->vtbl->destroy)
            priv->vtbl->destroy(priv->closure, window);
    }

    if (msg == WM_ERASEBKGND) {
        return TRUE;
    }

    if (msg == WM_PRINTCLIENT) {
        RECT r = { 0, 0, 0, 0 };
        GetClientRect(window, &r);

        ALF_Panel_Paint(priv, window, (HDC)wparam, &r);

        return TRUE;
    }

    if (msg == WM_PAINT) {
        PAINTSTRUCT ps;
        HDC dc = BeginPaint(window, &ps);

        ALF_Panel_Paint(priv, window, dc, &ps.rcPaint);

        EndPaint(window, &ps);

        return 0;
    }

    if (msg == ALF_WM_PANEL_SETVTABLE) {
        const ALFPanelSetVtblParams *params = (const ALFPanelSetVtblParams *)lparam;
        if (!params)
            return FALSE;

        priv->vtbl = params->vtbl;
        priv->closure = params->closure;
        if (priv->vtbl->attachvtbl) {
            priv->vtbl->attachvtbl(priv->closure, window);
        }
        return TRUE;
    }

    if (ALF_ShouldMessageBubble(window, msg, wparam, lparam))
        return SendMessage(GetParent(window), msg, wparam, lparam);

    if (msg == WM_SIZE) {
        ALF_Layout_Apply(&priv->layout, window);
    }

    LRESULT ret = 0;
    if (ALF_Layout_HandleMessage(&priv->layout, window, msg, wparam, lparam, &ret))
        return ret;

    return DefWindowProc(window, msg, wparam, lparam);
}

static LRESULT WINAPI
ALF__PanelWindowProc(HWND window, UINT msg, WPARAM wparam, LPARAM lparam)
{
    if (msg == WM_NCCREATE) {
        ALFPanelPriv *p = ALF_New(ALFPanelPriv, 1);

        ALF_Panel_IntializePriv(p);

        SetWindowLongPtr(window, 0, (LONG_PTR)p);
    }

    ALFPanelPriv *priv = (ALFPanelPriv *)GetWindowLongPtr(window, 0);

    if (msg == WM_NCDESTROY) {
        ALF_Panel_ClearPriv(priv);
        ALF_Free(priv);
        priv = NULL;
        SetWindowLongPtr(window, 0, 0);
    }

    if (priv) {
        if (priv->vtbl && priv->vtbl->message) {
            return priv->vtbl->message(priv->closure, window, msg, wparam, lparam);
        } else {
            return ALF_Panel_DefWindowProc(window, msg, wparam, lparam);
        }
    } else {
        return DefWindowProc(window, msg, wparam, lparam);
    }
}

void
ALF_RegisterPanelClass(void)
{
    WNDCLASS cls;
    ZeroMemory(&cls, sizeof(cls));

    TCHAR  classNameBuf[256];
    ALF_BuildUniqueName(classNameBuf, TEXT("ALFPanel."), (ULONG_PTR)&_alf_panelClass);

    cls.hInstance = ALF_HINSTANCE;
    cls.hCursor = LoadCursor(NULL, (LPTSTR)IDC_ARROW);
    cls.lpszClassName = classNameBuf;
    cls.cbWndExtra = sizeof(void*);
    cls.lpfnWndProc = ALF__PanelWindowProc;

    ATOM classatom = RegisterClass(&cls);
    if (!classatom)
        MessageBox(NULL, TEXT("FATAL: Could not register panel class"), NULL, MB_OK);

    _alf_panelClass = MAKEINTATOM(classatom);
}

HWND
ALF_CreatePanelWindow(HWND parent, WORD id)
{
    return CreateWindowEx(WS_EX_CONTROLPARENT,
                          _alf_panelClass,
                          TEXT(""),
                          WS_CHILD | WS_VISIBLE | WS_CLIPCHILDREN,
                          0, 0, 0, 0,
                          parent,
                          (HMENU)(int)id,
                          ALF_HINSTANCE,
                          NULL);
}

HWND
ALF_AddPanel(HWND parent, WORD id, int x, int y)
{
    HWND hwndPanel = ALF_CreatePanelWindow(parent, id);

    ALF_AddWidget(parent, x, y, hwndPanel, 0, 0, ALF_LAYOUT_SIZE_QUERY | ALF_LAYOUT_INHERITFONT | ALF_LAYOUT_INHERITBGCOLOR | ALF_LAYOUT_SENDBGCHANGE | ALF_LAYOUT_SENDDPICHANGE);

    return hwndPanel;
}