// dvx_app.h — Layer 5: Application API for DVX GUI
#ifndef DVX_APP_H
#define DVX_APP_H

#include "dvxTypes.h"
#include "dvxVideo.h"
#include "dvxDraw.h"
#include "dvxComp.h"
#include "dvxWm.h"

#include <time.h>

// ============================================================
// Application context
// ============================================================

typedef struct AppContextT {
    DisplayT      display;
    WindowStackT  stack;
    DirtyListT    dirty;
    BlitOpsT      blitOps;
    BitmapFontT   font;
    ColorSchemeT  colors;
    PopupStateT   popup;
    SysMenuStateT sysMenu;
    KbMoveResizeT kbMoveResize;
    CursorT       cursors[5];     // indexed by CURSOR_xxx
    int32_t       cursorId;       // active cursor shape
    uint32_t      cursorFg;       // pre-packed cursor colors
    uint32_t      cursorBg;
    bool          running;
    int32_t       mouseX;
    int32_t       mouseY;
    int32_t       mouseButtons;
    int32_t       keyModifiers;    // current BIOS shift state (KEY_MOD_xxx)
    int32_t       prevMouseX;
    int32_t       prevMouseY;
    int32_t       prevMouseButtons;
    clock_t       lastIconClickTime;
    int32_t       lastIconClickId;    // window ID of last-clicked minimized icon (-1 = none)
    clock_t       lastCloseClickTime;
    int32_t       lastCloseClickId;   // window ID of last-clicked close gadget (-1 = none)
    int32_t       iconRefreshIdx;     // next minimized icon to refresh (staggered)
    int32_t       frameCount;         // frame counter for periodic tasks
    void        (*idleCallback)(void *ctx); // called instead of yield when non-NULL
    void         *idleCtx;
    WindowT     *modalWindow;   // if non-NULL, only this window receives input
    // Tooltip state
    clock_t      tooltipHoverStart;    // when mouse stopped moving
    const char  *tooltipText;          // text to show (NULL = hidden)
    int32_t      tooltipX;             // screen position
    int32_t      tooltipY;
    int32_t      tooltipW;             // size (pre-computed)
    int32_t      tooltipH;
    uint32_t     charHeightRecip;      // fixed-point 16.16 reciprocal of font.charHeight
} AppContextT;

// Initialize the application (VESA mode, input, etc.)
int32_t dvxInit(AppContextT *ctx, int32_t requestedW, int32_t requestedH, int32_t preferredBpp);

// Shut down and restore text mode
void dvxShutdown(AppContextT *ctx);

// Run the main event loop (returns when ctx->running is set to false)
void dvxRun(AppContextT *ctx);

// Process one iteration of the event loop.
// Returns true if the GUI is still running, false if it wants to exit.
bool dvxUpdate(AppContextT *ctx);

// Create a window
WindowT *dvxCreateWindow(AppContextT *ctx, const char *title, int32_t x, int32_t y, int32_t w, int32_t h, bool resizable);

// Create a centered window (position computed from screen size)
WindowT *dvxCreateWindowCentered(AppContextT *ctx, const char *title, int32_t w, int32_t h, bool resizable);

// Destroy a window
void dvxDestroyWindow(AppContextT *ctx, WindowT *win);

// Resize a window to fit its widget tree's minimum size
void dvxFitWindow(AppContextT *ctx, WindowT *win);

// Invalidate a region of a window's content area (triggers repaint)
void dvxInvalidateRect(AppContextT *ctx, WindowT *win, int32_t x, int32_t y, int32_t w, int32_t h);

// Invalidate entire window content
void dvxInvalidateWindow(AppContextT *ctx, WindowT *win);

// Minimize a window (show as icon at bottom of screen)
void dvxMinimizeWindow(AppContextT *ctx, WindowT *win);

// Maximize a window (expand to fill screen or maxW/maxH)
void dvxMaximizeWindow(AppContextT *ctx, WindowT *win);

// Request exit from main loop
void dvxQuit(AppContextT *ctx);

// Save the entire screen to a PNG file (returns 0 on success, -1 on failure)
int32_t dvxScreenshot(AppContextT *ctx, const char *path);

// Set window title
void dvxSetTitle(AppContextT *ctx, WindowT *win, const char *title);

// Get the default font
const BitmapFontT *dvxGetFont(const AppContextT *ctx);

// Get the color scheme
const ColorSchemeT *dvxGetColors(const AppContextT *ctx);

// Get the display
DisplayT *dvxGetDisplay(AppContextT *ctx);

// Get blit ops
const BlitOpsT *dvxGetBlitOps(const AppContextT *ctx);

// Load an icon for a window from an image file
int32_t dvxSetWindowIcon(AppContextT *ctx, WindowT *win, const char *path);

// Save a window's content to a PNG file (returns 0 on success, -1 on failure)
int32_t dvxWindowScreenshot(AppContextT *ctx, WindowT *win, const char *path);

// Create an accelerator table (caller must free with dvxFreeAccelTable)
AccelTableT *dvxCreateAccelTable(void);

// Free an accelerator table
void dvxFreeAccelTable(AccelTableT *table);

// Add an entry to an accelerator table
void dvxAddAccel(AccelTableT *table, int32_t key, int32_t modifiers, int32_t cmdId);

// Arrange windows in a staggered diagonal cascade pattern
void dvxCascadeWindows(AppContextT *ctx);

// Tile windows in a grid pattern
void dvxTileWindows(AppContextT *ctx);

// Tile windows horizontally (side by side left to right, full height)
void dvxTileWindowsH(AppContextT *ctx);

// Tile windows vertically (stacked top to bottom, full width)
void dvxTileWindowsV(AppContextT *ctx);

// Copy text to the shared clipboard
void dvxClipboardCopy(const char *text, int32_t len);

// Get clipboard contents (returns pointer to internal buffer, NULL if empty)
const char *dvxClipboardGet(int32_t *outLen);

#endif // DVX_APP_H