#define DVX_WIDGET_IMPL
// widgetListView.c  -- ListView (multi-column list) widget
//
// A multi-column list with clickable/sortable column headers, horizontal
// and vertical scrolling, column resize by dragging header borders, and
// multi-select support. This is the most complex widget in the toolkit.
//
// Data model: cell data is stored as a flat array of const char* pointers
// in row-major order (cellData[row * colCount + col]). This external data
// model (pointers, not copies) keeps memory usage minimal and avoids
// copying strings that the application already owns.
//
// ListView state is heap-allocated separately (ListViewDataT*) rather than
// inlined in the widget union because the state is too large for a union
// member  -- it includes per-column resolved widths, sort index, selection
// bits, and numerous scroll/drag state fields.
//
// Sort: clicking a column header toggles sort direction. Sorting uses an
// indirection array (sortIndex) rather than rearranging the cellData. This
// is critical because:
//   1. The application owns cellData and may not expect it to be mutated
//   2. Multi-select selBits are indexed by data row, not display row  --
//      rearranging data would invalidate all selection state
//   3. The indirection allows O(1) display<->data row mapping
//
// Insertion sort is used because it's stable (preserves original order for
// equal keys) and has good performance for the typical case of partially-sorted
// data. For the row counts typical in a DOS GUI (hundreds, not millions),
// insertion sort's O(n^2) worst case is acceptable and the constant factors
// are lower than quicksort.
//
// Column widths support four sizing modes via a tagged integer:
//   - 0: auto-size (scan all data for widest string)
//   - positive small: character count (resolved via font->charWidth)
//   - positive large: pixel width
//   - negative: percentage of parent width
// The resolution is done lazily in resolveColumnWidths, which is called on
// first paint or mouse event after data changes.
//
// Column resize: dragging a column header border (3px hot zone) resizes the
// column. The drag state (resizeCol, resizeStartX, resizeOrigW, resizeDragging)
// is stored in the ListView's private data. The core only keeps sResizeListView
// to route drag events. A minimum column width (LISTVIEW_MIN_COL_W) prevents
// columns from collapsing to zero.
//
// Horizontal scrolling is needed when total column width exceeds the widget's
// inner width. Both headers and data rows are offset by scrollPosH. The
// horizontal scrollbar appears automatically when needed, and its presence
// may trigger the vertical scrollbar to appear (and vice versa)  -- this
// two-pass logic handles the interdependency correctly.

#include "dvxWgtP.h"
#include "../listhelp/listHelp.h"

#define LISTVIEW_BORDER      2
#define LISTVIEW_MIN_COL_W   20

static int32_t sTypeId = -1;

#include <stdlib.h>
#include <string.h>
#include "stb_ds_wrap.h"

#define LISTVIEW_MAX_COLS 16
#define LISTVIEW_PAD      3
#define LISTVIEW_MIN_ROWS 4
#define LISTVIEW_COL_PAD  6
#define LISTVIEW_SORT_W   10

// ListView private data  -- heap-allocated per widget, stored in w->data.
// This replaces the old as.listView union pointer. The struct includes
// column resize drag state that was previously in core globals.
typedef struct {
    const ListViewColT *cols;
    int32_t             colCount;
    const char        **cellData;
    int32_t             rowCount;
    int32_t             selectedIdx;
    int32_t             scrollPos;
    int32_t             scrollPosH;
    int32_t             sortCol;
    ListViewSortE       sortDir;
    int32_t             resolvedColW[LISTVIEW_MAX_COLS];
    int32_t             totalColW;
    int32_t            *sortIndex;
    bool                multiSelect;
    int32_t             anchorIdx;
    uint8_t            *selBits;
    bool                reorderable;
    int32_t             dragIdx;
    int32_t             dropIdx;
    void              (*onHeaderClick)(struct WidgetT *w, int32_t col, ListViewSortE dir);
    // Column resize drag state (moved from core globals)
    int32_t             resizeCol;
    int32_t             resizeStartX;
    int32_t             resizeOrigW;
    bool                resizeDragging;
    int32_t             sbDragOrient;
    int32_t             sbDragOff;
    // Owned cell storage for AddItem/RemoveRow/Clear/SetCell
    char               **ownedCells;   // stb_ds dynamic array of strdup'd strings
    bool                 ownsCells;    // true if cellData points to ownedCells
    int32_t              nextCell;     // next cell position for AddItem (row-major index)
} ListViewDataT;


// ============================================================
// Prototypes
// ============================================================

static void allocListViewSelBits(WidgetT *w);
static void listViewBuildSortIndex(WidgetT *w);
static void listViewSyncOwned(WidgetT *w);
static void resolveColumnWidths(WidgetT *w, const BitmapFontT *font);
static void widgetListViewScrollDragUpdate(WidgetT *w, int32_t orient, int32_t dragOff, int32_t mouseX, int32_t mouseY);
void wgtListViewSelectAll(WidgetT *w);


// ============================================================
// allocListViewSelBits
// ============================================================

static void allocListViewSelBits(WidgetT *w) {
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (lv->selBits) {
        free(lv->selBits);
        lv->selBits = NULL;
    }

    int32_t count = lv->rowCount;

    if (count > 0 && lv->multiSelect) {
        lv->selBits = (uint8_t *)calloc(count, 1);
    }
}


// ============================================================
// listViewBuildSortIndex
// ============================================================
//
// Build or rebuild the sortIndex array. Uses insertion sort
// (stable) on the sort column. If no sort is active, frees
// the index so paint uses natural order.

// Build the sort indirection array. Rather than rearranging cellData (which
// the application owns and indexes into), we maintain a separate array that
// maps display-row -> data-row. Paint and keyboard navigation work in display-row
// space, then map through sortIndex to get the data row for cell lookups and
// selection operations. This decoupling is essential because selBits are
// indexed by data row  -- sorting must not invalidate selection state.
static void listViewBuildSortIndex(WidgetT *w) {
    ListViewDataT *lv = (ListViewDataT *)w->data;
    int32_t rowCount = lv->rowCount;
    int32_t sortCol  = lv->sortCol;
    int32_t colCount = lv->colCount;

    // No sort active  -- clear index
    if (sortCol < 0 || lv->sortDir == ListViewSortNoneE || rowCount <= 0) {
        if (lv->sortIndex) {
            free(lv->sortIndex);
            lv->sortIndex = NULL;
        }

        return;
    }

    // Allocate or reuse
    int32_t *idx = lv->sortIndex;

    if (!idx) {
        idx = (int32_t *)malloc(rowCount * sizeof(int32_t));

        if (!idx) {
            return;
        }

        lv->sortIndex = idx;
    }

    // Initialize identity
    for (int32_t i = 0; i < rowCount; i++) {
        idx[i] = i;
    }

    // Insertion sort  -- stable (equal elements keep their original order),
    // O(n^2) worst case but with very low constant factors. For typical
    // ListView row counts (10s to low 100s), this beats quicksort because
    // there's no recursion overhead, no stack usage, and the inner loop
    // is a simple pointer chase. On a 486, the predictable memory access
    // pattern also helps since insertion sort is cache-friendly (sequential
    // access to adjacent elements).
    bool ascending = (lv->sortDir == ListViewSortAscE);

    for (int32_t i = 1; i < rowCount; i++) {
        int32_t key = idx[i];
        const char *keyStr = lv->cellData[key * colCount + sortCol];

        if (!keyStr) {
            keyStr = "";
        }

        int32_t j = i - 1;

        while (j >= 0) {
            const char *jStr = lv->cellData[idx[j] * colCount + sortCol];

            if (!jStr) {
                jStr = "";
            }

            int32_t cmp = strcmp(jStr, keyStr);

            if (!ascending) {
                cmp = -cmp;
            }

            if (cmp <= 0) {
                break;
            }

            idx[j + 1] = idx[j];
            j--;
        }

        idx[j + 1] = key;
    }
}


// ============================================================
// listViewSyncOwned
// ============================================================

// Sync cellData/rowCount from ownedCells after mutation.
// Rebuilds sort index and selection bits, forces column width recalculation.
static void listViewSyncOwned(WidgetT *w) {
    ListViewDataT *lv = (ListViewDataT *)w->data;
    int32_t cellCount = (int32_t)arrlen(lv->ownedCells);

    lv->cellData  = (const char **)lv->ownedCells;
    lv->rowCount  = (lv->colCount > 0) ? cellCount / lv->colCount : 0;
    lv->totalColW = 0;
    lv->ownsCells = true;

    listViewBuildSortIndex(w);
    allocListViewSelBits(w);
    wgtInvalidate(w);
}


// ============================================================
// resolveColumnWidths
// ============================================================
//
// Resolve tagged column sizes (pixels, chars, percent, or auto)
// to actual pixel widths. Auto-sized columns (width==0) scan
// cellData for the widest string in that column.

// Resolve tagged column widths to actual pixel values. Column widths in the
// ListViewColT definition can be specified as:
//   0          = auto (scan data for widest string, include header)
//   positive   = passed to wgtResolveSize (handles px, chars, or percent)
//
// Auto-sizing scans all rows for the widest string in that column, which
// is O(rows * cols) but only runs once per data change (totalColW is reset
// to 0 when data changes, triggering recalculation on next paint/mouse).
static void resolveColumnWidths(WidgetT *w, const BitmapFontT *font) {
    ListViewDataT *lv = (ListViewDataT *)w->data;
    int32_t colCount = lv->colCount;
    int32_t parentW  = w->w - LISTVIEW_BORDER * 2;

    if (parentW < 0) {
        parentW = 0;
    }

    int32_t totalW = 0;

    for (int32_t c = 0; c < colCount; c++) {
        int32_t taggedW = lv->cols[c].width;

        if (taggedW == 0) {
            // Auto-size: scan data for widest string in this column
            int32_t maxLen = (int32_t)strlen(lv->cols[c].title);

            for (int32_t r = 0; r < lv->rowCount; r++) {
                const char *cell = lv->cellData[r * colCount + c];

                if (cell) {
                    int32_t slen = (int32_t)strlen(cell);

                    if (slen > maxLen) {
                        maxLen = slen;
                    }
                }
            }

            lv->resolvedColW[c] = maxLen * font->charWidth + LISTVIEW_COL_PAD;
        } else {
            lv->resolvedColW[c] = wgtResolveSize(taggedW, parentW, font->charWidth);
        }

        totalW += lv->resolvedColW[c];
    }

    lv->totalColW = totalW;
}


// ============================================================
// widgetListViewColBorderHit
// ============================================================
//
// Returns true if (vx, vy) is on a column header border (resize zone).
// Coordinates are in widget/virtual space (scroll-adjusted).

// Test if a point is on a column header border (within 3px). Used by the
// cursor-shape logic to show a resize cursor when hovering over column borders.
// The 3px zone on each side of the border line makes it easy to grab even
// on low-resolution displays where pixel-precise clicking is difficult.
bool widgetListViewColBorderHit(const WidgetT *w, int32_t vx, int32_t vy) {
    if (!w || w->type != sTypeId) {
        return false;
    }

    const ListViewDataT *lv = (const ListViewDataT *)w->data;

    if (lv->colCount == 0) {
        return false;
    }

    AppContextT       *ctx  = wgtGetContext(w);
    const BitmapFontT *font = &ctx->font;
    int32_t headerH   = font->charHeight + 4;
    int32_t headerTop = w->y + LISTVIEW_BORDER;

    if (vy < headerTop || vy >= headerTop + headerH) {
        return false;
    }

    int32_t colX = w->x + LISTVIEW_BORDER - lv->scrollPosH;

    for (int32_t c = 0; c < lv->colCount; c++) {
        int32_t border = colX + lv->resolvedColW[c];

        if (vx >= border - 3 && vx <= border + 3) {
            return true;
        }

        colX += lv->resolvedColW[c];
    }

    return false;
}


// ============================================================
// widgetListViewDestroy
// ============================================================

// Free all heap-allocated ListView state. The sortIndex and selBits are
// optional (may be NULL if no sort or single-select), so we check before
// freeing. The ListViewDataT struct itself is always freed.
void widgetListViewDestroy(WidgetT *w) {
    ListViewDataT *lv = (ListViewDataT *)w->data;

    for (int32_t i = 0; i < (int32_t)arrlen(lv->ownedCells); i++) {
        free(lv->ownedCells[i]);
    }
    arrfree(lv->ownedCells);
    free(lv->selBits);
    free(lv->sortIndex);
    free(lv);
    w->data = NULL;
}


// ============================================================
// wgtListView
// ============================================================

// ============================================================
// widgetListViewCalcMinSize
// ============================================================

void widgetListViewCalcMinSize(WidgetT *w, const BitmapFontT *font) {
    int32_t headerH = font->charHeight + 4;
    int32_t minW    = font->charWidth * 12 + LISTVIEW_BORDER * 2 + WGT_SB_W;

    w->calcMinW = minW;
    w->calcMinH = headerH + LISTVIEW_MIN_ROWS * font->charHeight + LISTVIEW_BORDER * 2;
}


// ============================================================
// widgetListViewOnKey
// ============================================================

// Key handling must account for the sort indirection layer. Navigation happens
// in display-row space (what the user sees on screen), but selection and data
// access happen in data-row space (the original cellData indices). This means:
//   1. Convert selectedIdx (data row) to display row via linear search in sortIndex
//   2. Navigate in display space (widgetNavigateIndex)
//   3. Convert back to data row via sortIndex[displayRow]
//   4. Update selectedIdx and selBits using data-row indices
//
// Shift-select for sorted views is particularly tricky: the range must be
// computed in display-row space (what the user sees as contiguous) but applied
// to the data-row selBits. This means the selected data rows may not be
// contiguous in the original data order.
void widgetListViewOnKey(WidgetT *w, int32_t key, int32_t mod) {
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (!w || w->type != sTypeId || lv->rowCount == 0) {
        return;
    }

    bool     multi    = lv->multiSelect;
    bool     shift    = (mod & KEY_MOD_SHIFT) != 0;
    bool     ctrl     = (mod & KEY_MOD_CTRL) != 0;
    int32_t  rowCount = lv->rowCount;
    int32_t *sortIdx  = lv->sortIndex;

    // Enter  -- activate selected item (same as double-click)
    if (key == '\r' || key == '\n') {
        if (w->onDblClick && lv->selectedIdx >= 0) {
            w->onDblClick(w);
        }

        return;
    }

    // Ctrl+A  -- select all (multi-select only)
    if (multi && ctrl && (key == 'a' || key == 'A' || key == 1)) {
        wgtListViewSelectAll(w);
        return;
    }

    // Space  -- toggle current item (multi-select only)
    if (multi && key == ' ') {
        int32_t sel = lv->selectedIdx;

        if (sel >= 0 && lv->selBits) {
            lv->selBits[sel] ^= 1;
            lv->anchorIdx = sel;
        }

        if (w->onChange) {
            w->onChange(w);
        }

        wgtInvalidatePaint(w);
        return;
    }

    // Find current display row from selectedIdx (data row)
    int32_t displaySel = -1;

    if (lv->selectedIdx >= 0) {
        if (sortIdx) {
            for (int32_t i = 0; i < rowCount; i++) {
                if (sortIdx[i] == lv->selectedIdx) {
                    displaySel = i;
                    break;
                }
            }
        } else {
            displaySel = lv->selectedIdx;
        }
    }

    // Compute visible rows for page up/down
    AppContextT       *ctx  = wgtGetContext(w);
    const BitmapFontT *font = &ctx->font;
    int32_t headerH      = font->charHeight + 4;
    int32_t innerH       = w->h - LISTVIEW_BORDER * 2 - headerH;
    int32_t visibleRows  = innerH / font->charHeight;

    if (visibleRows < 1) {
        visibleRows = 1;
    }

    int32_t newDisplaySel = widgetNavigateIndex(key, displaySel, rowCount, visibleRows);

    if (newDisplaySel < 0) {
        return;
    }

    displaySel = newDisplaySel;

    // Convert display row back to data row
    int32_t newDataRow = sortIdx ? sortIdx[displaySel] : displaySel;

    if (newDataRow == lv->selectedIdx) {
        return;
    }

    lv->selectedIdx = newDataRow;

    // Update multi-select
    if (multi && lv->selBits) {
        if (shift) {
            // Shift+arrow: range from anchor to new cursor (in data-row space)
            memset(lv->selBits, 0, rowCount);

            // Convert anchor to display row, then select display range mapped to data rows
            int32_t anchorDisplay = -1;
            int32_t anchor = lv->anchorIdx;

            if (sortIdx && anchor >= 0) {
                for (int32_t i = 0; i < rowCount; i++) {
                    if (sortIdx[i] == anchor) {
                        anchorDisplay = i;
                        break;
                    }
                }
            } else {
                anchorDisplay = anchor;
            }

            // Select all display rows in range, mapping to data rows
            int32_t lo = anchorDisplay < displaySel ? anchorDisplay : displaySel;
            int32_t hi = anchorDisplay > displaySel ? anchorDisplay : displaySel;

            if (lo < 0) {
                lo = 0;
            }

            if (hi >= rowCount) {
                hi = rowCount - 1;
            }

            for (int32_t i = lo; i <= hi; i++) {
                int32_t dr = sortIdx ? sortIdx[i] : i;
                lv->selBits[dr] = 1;
            }
        }
        // Plain arrow: just move cursor, leave selections untouched
    }

    // Scroll to keep selection visible (in display-row space)
    if (displaySel >= 0) {
        if (displaySel < lv->scrollPos) {
            lv->scrollPos = displaySel;
        } else if (displaySel >= lv->scrollPos + visibleRows) {
            lv->scrollPos = displaySel - visibleRows + 1;
        }
    }

    if (w->onChange) {
        w->onChange(w);
    }

    wgtInvalidatePaint(w);
}


// ============================================================
// widgetListViewOnMouse
// ============================================================

// Mouse handling is the most complex part of ListView. It handles four
// distinct hit regions (checked in priority order):
//   1. Vertical scrollbar (right edge, if visible)
//   2. Horizontal scrollbar (bottom edge, if visible)
//   3. Dead corner (when both scrollbars present  -- no action)
//   4. Column headers: resize drag (border +-3px) or sort toggle (click)
//   5. Data rows: item selection with Ctrl/Shift modifiers, double-click,
//      and drag-reorder initiation
//
// The scrollbar visibility calculation is repeated here (matching paint)
// because scrollbar presence depends on content/widget dimensions which
// may have changed since the last paint.
void widgetListViewOnMouse(WidgetT *hit, WidgetT *root, int32_t vx, int32_t vy) {
    sFocusedWidget = hit;
    ListViewDataT *lv = (ListViewDataT *)hit->data;

    AppContextT       *ctx  = (AppContextT *)root->userData;
    const BitmapFontT *font = &ctx->font;

    // Resolve column widths if needed
    if (lv->totalColW == 0 && lv->colCount > 0) {
        resolveColumnWidths(hit, font);
    }

    int32_t headerH     = font->charHeight + 4;
    int32_t innerH      = hit->h - LISTVIEW_BORDER * 2 - headerH;
    int32_t innerW      = hit->w - LISTVIEW_BORDER * 2;
    int32_t visibleRows = innerH / font->charHeight;
    int32_t totalColW   = lv->totalColW;
    bool    needVSb     = (lv->rowCount > visibleRows);
    bool    needHSb     = false;

    // Scrollbar interdependency: adding a vertical scrollbar reduces innerW,
    // which may cause columns to overflow and require a horizontal scrollbar.
    // Adding a horizontal scrollbar reduces innerH, which may require a
    // vertical scrollbar. This two-pass check handles the mutual dependency.
    if (needVSb) {
        innerW -= WGT_SB_W;
    }

    if (totalColW > innerW) {
        needHSb = true;
        innerH -= WGT_SB_W;
        visibleRows = innerH / font->charHeight;

        if (!needVSb && lv->rowCount > visibleRows) {
            needVSb = true;
            innerW -= WGT_SB_W;
        }
    }

    if (visibleRows < 1) {
        visibleRows = 1;
    }

    // Clamp scroll positions
    int32_t maxScrollV = lv->rowCount - visibleRows;
    int32_t maxScrollH = totalColW - innerW;

    if (maxScrollV < 0) {
        maxScrollV = 0;
    }

    if (maxScrollH < 0) {
        maxScrollH = 0;
    }

    lv->scrollPos  = clampInt(lv->scrollPos, 0, maxScrollV);
    lv->scrollPosH = clampInt(lv->scrollPosH, 0, maxScrollH);

    // Check vertical scrollbar
    if (needVSb) {
        int32_t sbX = hit->x + hit->w - LISTVIEW_BORDER - WGT_SB_W;
        int32_t sbY = hit->y + LISTVIEW_BORDER + headerH;

        if (vx >= sbX && vy >= sbY && vy < sbY + innerH) {
            int32_t    relY = vy - sbY;
            ScrollHitE sh   = widgetScrollbarHitTest(innerH, relY, lv->rowCount, visibleRows, lv->scrollPos);

            if (sh == ScrollHitArrowDecE) {
                if (lv->scrollPos > 0) {
                    lv->scrollPos--;
                }
            } else if (sh == ScrollHitArrowIncE) {
                if (lv->scrollPos < maxScrollV) {
                    lv->scrollPos++;
                }
            } else if (sh == ScrollHitPageDecE) {
                lv->scrollPos -= visibleRows;
                lv->scrollPos = clampInt(lv->scrollPos, 0, maxScrollV);
            } else if (sh == ScrollHitPageIncE) {
                lv->scrollPos += visibleRows;
                lv->scrollPos = clampInt(lv->scrollPos, 0, maxScrollV);
            } else if (sh == ScrollHitThumbE) {
                int32_t trackLen  = innerH - WGT_SB_W * 2;
                int32_t thumbPos;
                int32_t thumbSize;
                widgetScrollbarThumb(trackLen, lv->rowCount, visibleRows, lv->scrollPos, &thumbPos, &thumbSize);

                sDragWidget       = hit;
                lv->sbDragOrient = 0;
                lv->sbDragOff    = relY - WGT_SB_W - thumbPos;
            }

            return;
        }
    }

    // Check horizontal scrollbar
    if (needHSb) {
        int32_t sbX = hit->x + LISTVIEW_BORDER;
        int32_t sbY = hit->y + hit->h - LISTVIEW_BORDER - WGT_SB_W;

        if (vy >= sbY && vx >= sbX && vx < sbX + innerW) {
            int32_t relX     = vx - sbX;
            int32_t pageSize = innerW - font->charWidth;

            if (pageSize < font->charWidth) {
                pageSize = font->charWidth;
            }

            ScrollHitE sh = widgetScrollbarHitTest(innerW, relX, totalColW, innerW, lv->scrollPosH);

            if (sh == ScrollHitArrowDecE) {
                lv->scrollPosH -= font->charWidth;
            } else if (sh == ScrollHitArrowIncE) {
                lv->scrollPosH += font->charWidth;
            } else if (sh == ScrollHitPageDecE) {
                lv->scrollPosH -= pageSize;
            } else if (sh == ScrollHitPageIncE) {
                lv->scrollPosH += pageSize;
            } else if (sh == ScrollHitThumbE) {
                int32_t trackLen  = innerW - WGT_SB_W * 2;
                int32_t thumbPos;
                int32_t thumbSize;
                widgetScrollbarThumb(trackLen, totalColW, innerW, lv->scrollPosH, &thumbPos, &thumbSize);

                sDragWidget       = hit;
                lv->sbDragOrient = 1;
                lv->sbDragOff    = relX - WGT_SB_W - thumbPos;
            }

            lv->scrollPosH = clampInt(lv->scrollPosH, 0, maxScrollH);
            return;
        }
    }

    // Check dead corner (both scrollbars present)
    if (needVSb && needHSb) {
        int32_t cornerX = hit->x + hit->w - LISTVIEW_BORDER - WGT_SB_W;
        int32_t cornerY = hit->y + hit->h - LISTVIEW_BORDER - WGT_SB_W;

        if (vx >= cornerX && vy >= cornerY) {
            return;
        }
    }

    // Check column header area
    int32_t headerTop = hit->y + LISTVIEW_BORDER;

    if (vy >= headerTop && vy < headerTop + headerH) {
        // Check for column border resize (3px zone on each side of border)
        int32_t colX = hit->x + LISTVIEW_BORDER - lv->scrollPosH;

        for (int32_t c = 0; c < lv->colCount; c++) {
            int32_t cw     = lv->resolvedColW[c];
            int32_t border = colX + cw;

            if (vx >= border - 3 && vx <= border + 3 && c < lv->colCount) {
                if (multiClickDetect(vx, vy) >= 2) {
                    // Double-click on column border: auto-size to fit content
                    int32_t maxLen = (int32_t)strlen(lv->cols[c].title);

                    for (int32_t r = 0; r < lv->rowCount; r++) {
                        const char *cell = lv->cellData[r * lv->colCount + c];

                        if (cell) {
                            int32_t slen = (int32_t)strlen(cell);

                            if (slen > maxLen) {
                                maxLen = slen;
                            }
                        }
                    }

                    int32_t newW = maxLen * font->charWidth + LISTVIEW_COL_PAD;

                    if (newW < LISTVIEW_MIN_COL_W) {
                        newW = LISTVIEW_MIN_COL_W;
                    }

                    lv->resolvedColW[c] = newW;

                    // Recalculate totalColW
                    int32_t total = 0;

                    for (int32_t tc = 0; tc < lv->colCount; tc++) {
                        total += lv->resolvedColW[tc];
                    }

                    lv->totalColW = total;
                    wgtInvalidatePaint(hit);
                } else {
                    // Start column resize drag (deferred until mouse moves)
                    sDragWidget        = hit;
                    lv->sbDragOrient   = -1;
                    lv->resizeCol      = c;
                    lv->resizeStartX   = vx;
                    lv->resizeOrigW    = cw;
                    lv->resizeDragging = false;
                }

                return;
            }

            colX += cw;
        }

        // Not on a border  -- check for sort click (disabled when reorderable
        // since sorting conflicts with manual ordering). Clicking a column
        // toggles between ascending/descending; clicking a different column
        // starts ascending.
        if (!lv->reorderable) {
            colX = hit->x + LISTVIEW_BORDER - lv->scrollPosH;

            for (int32_t c = 0; c < lv->colCount; c++) {
                int32_t cw = lv->resolvedColW[c];

                if (vx >= colX && vx < colX + cw) {
                    // Toggle sort direction for this column
                    if (lv->sortCol == c) {
                        if (lv->sortDir == ListViewSortAscE) {
                            lv->sortDir = ListViewSortDescE;
                        } else {
                            lv->sortDir = ListViewSortAscE;
                        }
                    } else {
                        lv->sortCol = c;
                        lv->sortDir = ListViewSortAscE;
                    }

                    listViewBuildSortIndex(hit);

                    if (lv->onHeaderClick) {
                        lv->onHeaderClick(hit, c, lv->sortDir);
                    }

                    wgtInvalidatePaint(hit);
                    return;
                }

                colX += cw;
            }
        }

        return;
    }

    // Click on data area
    int32_t dataTop = headerTop + headerH;
    int32_t relY    = vy - dataTop;

    if (relY < 0) {
        return;
    }

    int32_t clickedRow = relY / font->charHeight;
    int32_t displayRow = lv->scrollPos + clickedRow;

    if (displayRow >= 0 && displayRow < lv->rowCount) {
        int32_t dataRow = lv->sortIndex ? lv->sortIndex[displayRow] : displayRow;
        lv->selectedIdx = dataRow;

        bool multi = lv->multiSelect;
        bool shift = (ctx->keyModifiers & KEY_MOD_SHIFT) != 0;
        bool ctrl  = (ctx->keyModifiers & KEY_MOD_CTRL) != 0;

        if (multi && lv->selBits) {
            if (ctrl) {
                // Ctrl+click: toggle item, update anchor
                lv->selBits[dataRow] ^= 1;
                lv->anchorIdx = dataRow;
            } else if (shift) {
                // Shift+click: range from anchor to clicked (in display-row space)
                memset(lv->selBits, 0, lv->rowCount);

                int32_t anchorDisplay = -1;
                int32_t anchor = lv->anchorIdx;

                if (lv->sortIndex && anchor >= 0) {
                    for (int32_t i = 0; i < lv->rowCount; i++) {
                        if (lv->sortIndex[i] == anchor) {
                            anchorDisplay = i;
                            break;
                        }
                    }
                } else {
                    anchorDisplay = anchor;
                }

                int32_t lo = anchorDisplay < displayRow ? anchorDisplay : displayRow;
                int32_t hi = anchorDisplay > displayRow ? anchorDisplay : displayRow;

                if (lo < 0) {
                    lo = 0;
                }

                if (hi >= lv->rowCount) {
                    hi = lv->rowCount - 1;
                }

                for (int32_t i = lo; i <= hi; i++) {
                    int32_t dr = lv->sortIndex ? lv->sortIndex[i] : i;
                    lv->selBits[dr] = 1;
                }
            } else {
                // Plain click: select only this item, update anchor
                memset(lv->selBits, 0, lv->rowCount);
                lv->selBits[dataRow] = 1;
                lv->anchorIdx = dataRow;
            }
        }

        if (hit->onChange) {
            hit->onChange(hit);
        }

        // Double-click: fire onDblClick
        if (hit->onDblClick && multiClickDetect(vx, vy) >= 2) {
            hit->onDblClick(hit);
        }

        // Initiate drag-reorder if enabled (not from modifier clicks)
        if (lv->reorderable && !shift && !ctrl) {
            lv->dragIdx = dataRow;
            lv->dropIdx = dataRow;
            sDragWidget = hit;
        }
    }

    wgtInvalidatePaint(hit);
}


// ============================================================
// widgetListViewPaint
// ============================================================

// Paint: the most involved paint function in the widget toolkit. Renders
// in layers:
//   1. Outer sunken bevel border
//   2. Column headers (clipped to content width, scrolled by scrollPosH):
//      each header is a raised bevel button with centered text and optional
//      sort indicator (up/down triangle)
//   3. Data rows (clipped to data area, scrolled both H and V):
//      background fill, then per-cell text rendering with alignment, then
//      selection highlight, then cursor focus rect in multi-select mode
//   4. Drag-reorder insertion line (if active)
//   5. Scrollbars (V and/or H, with dead corner fill)
//   6. Outer focus rect
//
// Clip rectangles are saved/restored around the header and data sections to
// prevent rendering from bleeding into the scrollbar or border areas. This
// is cheaper than per-cell clipping and handles horizontal scroll correctly
// (partially visible columns at the edges are clipped by the display's clip
// rect rather than by the draw calls).
void widgetListViewPaint(WidgetT *w, DisplayT *d, const BlitOpsT *ops, const BitmapFontT *font, const ColorSchemeT *colors) {
    ListViewDataT *lv = (ListViewDataT *)w->data;
    uint32_t fg = w->fgColor ? w->fgColor : colors->contentFg;
    uint32_t bg = w->bgColor ? w->bgColor : colors->contentBg;

    // Resolve column widths if needed
    if (lv->totalColW == 0 && lv->colCount > 0) {
        resolveColumnWidths(w, font);
    }

    int32_t headerH     = font->charHeight + 4;
    int32_t innerH      = w->h - LISTVIEW_BORDER * 2 - headerH;
    int32_t innerW      = w->w - LISTVIEW_BORDER * 2;
    int32_t visibleRows = innerH / font->charHeight;
    int32_t totalColW   = lv->totalColW;
    bool    needVSb     = (lv->rowCount > visibleRows);
    bool    needHSb     = false;

    if (needVSb) {
        innerW -= WGT_SB_W;
    }

    if (totalColW > innerW) {
        needHSb = true;
        innerH -= WGT_SB_W;
        visibleRows = innerH / font->charHeight;

        if (!needVSb && lv->rowCount > visibleRows) {
            needVSb = true;
            innerW -= WGT_SB_W;
        }
    }

    if (visibleRows < 1) {
        visibleRows = 1;
    }

    // Sunken border
    BevelStyleT bevel = BEVEL_SUNKEN(colors, bg, 2);
    drawBevel(d, ops, w->x, w->y, w->w, w->h, &bevel);

    // Clamp scroll positions
    int32_t maxScrollV = lv->rowCount - visibleRows;
    int32_t maxScrollH = totalColW - innerW;

    if (maxScrollV < 0) {
        maxScrollV = 0;
    }

    if (maxScrollH < 0) {
        maxScrollH = 0;
    }

    lv->scrollPos  = clampInt(lv->scrollPos, 0, maxScrollV);
    lv->scrollPosH = clampInt(lv->scrollPosH, 0, maxScrollH);

    int32_t baseX    = w->x + LISTVIEW_BORDER;
    int32_t baseY    = w->y + LISTVIEW_BORDER;
    int32_t colCount = lv->colCount;

    // ---- Draw column headers ----
    {
        // Clip headers to the content area width
        int32_t oldClipX = d->clipX;
        int32_t oldClipY = d->clipY;
        int32_t oldClipW = d->clipW;
        int32_t oldClipH = d->clipH;
        setClipRect(d, baseX, baseY, innerW, headerH);

        int32_t hdrX = baseX - lv->scrollPosH;
        BevelStyleT hdrBevel = BEVEL_RAISED(colors, 1);

        for (int32_t c = 0; c < colCount; c++) {
            int32_t cw = lv->resolvedColW[c];

            // Draw raised button for header
            drawBevel(d, ops, hdrX, baseY, cw, headerH, &hdrBevel);

            // Header text
            int32_t textX = hdrX + LISTVIEW_PAD;
            int32_t textY = baseY + 2;
            int32_t availTextW = cw - LISTVIEW_PAD * 2;

            // Reserve space for sort indicator if this is the sort column
            if (c == lv->sortCol && lv->sortDir != ListViewSortNoneE) {
                availTextW -= LISTVIEW_SORT_W;
            }

            if (lv->cols[c].title) {
                int32_t titleLen = (int32_t)strlen(lv->cols[c].title);
                int32_t titleW   = titleLen * font->charWidth;

                if (titleW > availTextW) {
                    titleLen = availTextW / font->charWidth;
                }

                if (titleLen > 0) {
                    drawTextN(d, ops, font, textX, textY, lv->cols[c].title, titleLen, colors->contentFg, colors->windowFace, true);
                }
            }

            // Sort indicator: a small filled triangle (4px tall) in the header.
            // Up triangle for ascending, down triangle for descending. Drawn as
            // horizontal lines of increasing/decreasing width, same technique as
            // the dropdown arrow glyph.
            if (c == lv->sortCol && lv->sortDir != ListViewSortNoneE) {
                int32_t cx = hdrX + cw - LISTVIEW_SORT_W / 2 - LISTVIEW_PAD;
                int32_t cy = baseY + headerH / 2;

                if (lv->sortDir == ListViewSortAscE) {
                    // Up triangle (ascending)
                    for (int32_t i = 0; i < 4; i++) {
                        drawHLine(d, ops, cx - i, cy - 2 + i, 1 + i * 2, colors->contentFg);
                    }
                } else {
                    // Down triangle (descending)
                    for (int32_t i = 0; i < 4; i++) {
                        drawHLine(d, ops, cx - 3 + i, cy - 1 + i, 7 - i * 2, colors->contentFg);
                    }
                }
            }

            hdrX += cw;
        }

        // Fill any remaining header space to the right of columns
        if (hdrX < baseX + innerW) {
            drawBevel(d, ops, hdrX, baseY, baseX + innerW - hdrX, headerH, &hdrBevel);
        }

        setClipRect(d, oldClipX, oldClipY, oldClipW, oldClipH);
    }

    // ---- Draw data rows ----
    {
        int32_t dataY = baseY + headerH;

        // Set clip rect to data area
        int32_t oldClipX = d->clipX;
        int32_t oldClipY = d->clipY;
        int32_t oldClipW = d->clipW;
        int32_t oldClipH = d->clipH;
        setClipRect(d, baseX, dataY, innerW, innerH);

        int32_t  scrollPos  = lv->scrollPos;
        int32_t *sortIdx    = lv->sortIndex;

        // Fill entire data area background first. This is done as a single
        // rectFill rather than per-row because it's cheaper to fill once and
        // then overdraw selected rows than to compute and fill each unselected
        // row's background separately.
        rectFill(d, ops, baseX, dataY, innerW, innerH, bg);

        bool     multi   = lv->multiSelect;
        uint8_t *selBits = lv->selBits;

        for (int32_t i = 0; i < visibleRows && (scrollPos + i) < lv->rowCount; i++) {
            int32_t  displayRow = scrollPos + i;
            int32_t  dataRow    = sortIdx ? sortIdx[displayRow] : displayRow;
            int32_t  iy         = dataY + i * font->charHeight;
            uint32_t ifg        = fg;
            uint32_t ibg        = bg;

            bool selected = false;

            if (multi && selBits) {
                selected = selBits[dataRow] != 0;
            } else {
                selected = (dataRow == lv->selectedIdx);
            }

            if (selected) {
                ifg = colors->menuHighlightFg;
                ibg = colors->menuHighlightBg;
                rectFill(d, ops, baseX, iy, innerW, font->charHeight, ibg);
            }

            // Draw each cell
            int32_t cellX = baseX - lv->scrollPosH;

            for (int32_t c = 0; c < colCount; c++) {
                int32_t     cw   = lv->resolvedColW[c];
                const char *cell = lv->cellData[dataRow * colCount + c];

                if (cell) {
                    int32_t cellLen  = (int32_t)strlen(cell);
                    int32_t maxChars = (cw - LISTVIEW_PAD * 2) / font->charWidth;

                    if (maxChars < 0) {
                        maxChars = 0;
                    }

                    if (cellLen > maxChars) {
                        cellLen = maxChars;
                    }

                    int32_t tx = cellX + LISTVIEW_PAD;

                    // Column alignment: left (default), right, or center.
                    // Right/center alignment compute the available width and
                    // offset the text start position accordingly. This is done
                    // per-cell rather than using a general-purpose aligned draw
                    // function to keep the inner loop simple and avoid extra
                    // function call overhead per cell.
                    if (lv->cols[c].align == ListViewAlignRightE) {
                        int32_t renderedW = cellLen * font->charWidth;
                        int32_t availW    = cw - LISTVIEW_PAD * 2;
                        tx = cellX + LISTVIEW_PAD + (availW - renderedW);
                    } else if (lv->cols[c].align == ListViewAlignCenterE) {
                        int32_t renderedW = cellLen * font->charWidth;
                        int32_t availW    = cw - LISTVIEW_PAD * 2;
                        tx = cellX + LISTVIEW_PAD + (availW - renderedW) / 2;
                    }

                    if (cellLen > 0) {
                        drawTextN(d, ops, font, tx, iy, cell, cellLen, ifg, ibg, true);
                    }
                }

                cellX += cw;
            }

            // Draw cursor focus rect in multi-select mode (on top of text)
            if (multi && dataRow == lv->selectedIdx && w == sFocusedWidget) {
                drawFocusRect(d, ops, baseX, iy, innerW, font->charHeight, fg);
            }
        }

        // Draw drag-reorder insertion indicator
        if (lv->reorderable && lv->dragIdx >= 0 && lv->dropIdx >= 0) {
            int32_t drop  = lv->dropIdx;
            int32_t lineY = dataY + (drop - lv->scrollPos) * font->charHeight;

            if (lineY >= dataY && lineY <= dataY + innerH) {
                drawHLine(d, ops, baseX, lineY, innerW, fg);
                drawHLine(d, ops, baseX, lineY + 1, innerW, fg);
            }
        }

        setClipRect(d, oldClipX, oldClipY, oldClipW, oldClipH);
    }

    // ---- Draw scrollbars ----
    if (needVSb) {
        int32_t sbX = w->x + w->w - LISTVIEW_BORDER - WGT_SB_W;
        int32_t sbY = w->y + LISTVIEW_BORDER + headerH;
        widgetDrawScrollbarV(d, ops, colors, sbX, sbY, innerH, lv->rowCount, visibleRows, lv->scrollPos);
    }

    if (needHSb) {
        int32_t sbX = w->x + LISTVIEW_BORDER;
        int32_t sbY = w->y + w->h - LISTVIEW_BORDER - WGT_SB_W;
        widgetDrawScrollbarH(d, ops, colors, sbX, sbY, innerW, totalColW, innerW, lv->scrollPosH);

        // Fill the dead corner when both scrollbars are present. This is the
        // small square at the intersection of the two scrollbars (bottom-right)
        // that doesn't belong to either. Without filling it, stale content
        // from previous paints would show through.
        if (needVSb) {
            rectFill(d, ops, sbX + innerW, sbY, WGT_SB_W, WGT_SB_W, colors->windowFace);
        }
    }

    if (w == sFocusedWidget) {
        drawFocusRect(d, ops, w->x + 1, w->y + 1, w->w - 2, w->h - 2, fg);
    }
}


// ============================================================
// Public accessors (kept here due to static helper dependencies)
// ============================================================

void wgtListViewSetColumns(WidgetT *w, const ListViewColT *cols, int32_t count) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (count > LISTVIEW_MAX_COLS) {
        count = LISTVIEW_MAX_COLS;
    }

    lv->cols      = cols;
    lv->colCount  = count;
    lv->totalColW = 0;

    if (lv->rowCount > 0) {
        AppContextT *ctx = wgtGetContext(w);

        if (ctx) {
            resolveColumnWidths(w, &ctx->font);
        }
    }

    wgtInvalidate(w);
}


void wgtListViewSetData(WidgetT *w, const char **cellData, int32_t rowCount) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (lv->sortIndex) {
        free(lv->sortIndex);
        lv->sortIndex = NULL;
    }

    lv->cellData  = cellData;
    lv->rowCount  = rowCount;
    lv->totalColW = 0;

    if (lv->selectedIdx >= rowCount) {
        lv->selectedIdx = rowCount > 0 ? 0 : -1;
    }

    if (lv->selectedIdx < 0 && rowCount > 0) {
        lv->selectedIdx = 0;
    }

    lv->anchorIdx = lv->selectedIdx;

    listViewBuildSortIndex(w);
    allocListViewSelBits(w);

    if (lv->selBits && lv->selectedIdx >= 0) {
        lv->selBits[lv->selectedIdx] = 1;
    }

    if (lv->colCount > 0) {
        AppContextT *ctx = wgtGetContext(w);

        if (ctx) {
            resolveColumnWidths(w, &ctx->font);
        }
    }

    wgtInvalidate(w);
}


void wgtListViewSetMultiSelect(WidgetT *w, bool multi) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    lv->multiSelect = multi;
    allocListViewSelBits(w);

    if (lv->selBits && lv->selectedIdx >= 0) {
        lv->selBits[lv->selectedIdx] = 1;
    }
}


void wgtListViewSetReorderable(WidgetT *w, bool reorderable) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    lv->reorderable = reorderable;

    if (reorderable) {
        lv->sortCol = -1;
        lv->sortDir = ListViewSortNoneE;

        if (lv->sortIndex) {
            free(lv->sortIndex);
            lv->sortIndex = NULL;
        }
    }
}


void wgtListViewSetSort(WidgetT *w, int32_t col, ListViewSortE dir) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    lv->sortCol = col;
    lv->sortDir = dir;
    listViewBuildSortIndex(w);
    wgtInvalidatePaint(w);
}


// ============================================================
// widgetListViewScrollDragUpdate
// ============================================================

// Handle column resize drag. orient == -1 means column resize (sent by
// widgetEvent.c when sResizeListView is set). The drag is deferred: we
// don't start modifying column widths until the mouse actually moves from
// the initial click position. This prevents accidental resizes from stray
// clicks on column borders.
static void widgetListViewScrollDragUpdate(WidgetT *w, int32_t orient, int32_t dragOff, int32_t mouseX, int32_t mouseY) {
    ListViewDataT *lv = (ListViewDataT *)w->data;

    // orient == -1 means column resize drag
    if (orient == -1) {
        if (!lv->resizeDragging) {
            if (mouseX == lv->resizeStartX) {
                return;
            }
            lv->resizeDragging = true;
        }

        int32_t delta = mouseX - lv->resizeStartX;
        int32_t newW  = lv->resizeOrigW + delta;

        if (newW < LISTVIEW_MIN_COL_W) {
            newW = LISTVIEW_MIN_COL_W;
        }

        if (newW != lv->resolvedColW[lv->resizeCol]) {
            lv->resolvedColW[lv->resizeCol] = newW;

            int32_t total = 0;

            for (int32_t c = 0; c < lv->colCount; c++) {
                total += lv->resolvedColW[c];
            }

            lv->totalColW = total;
        }

        return;
    }

    AppContextT       *ctx  = wgtGetContext(w);
    const BitmapFontT *font = &ctx->font;

    int32_t headerH     = font->charHeight + 4;
    int32_t innerH      = w->h - LISTVIEW_BORDER * 2 - headerH;
    int32_t innerW      = w->w - LISTVIEW_BORDER * 2;
    int32_t visibleRows = innerH / font->charHeight;
    int32_t totalColW   = lv->totalColW;
    bool    needVSb     = (lv->rowCount > visibleRows);

    if (needVSb) {
        innerW -= WGT_SB_W;
    }

    if (totalColW > innerW) {
        innerH -= WGT_SB_W;
        visibleRows = innerH / font->charHeight;

        if (!needVSb && lv->rowCount > visibleRows) {
            needVSb = true;
            innerW -= WGT_SB_W;
        }
    }

    if (visibleRows < 1) {
        visibleRows = 1;
    }

    if (orient == 0) {
        // Vertical scrollbar drag
        int32_t maxScroll = lv->rowCount - visibleRows;

        if (maxScroll <= 0) {
            return;
        }

        int32_t trackLen = innerH - WGT_SB_W * 2;
        int32_t thumbPos;
        int32_t thumbSize;
        widgetScrollbarThumb(trackLen, lv->rowCount, visibleRows, lv->scrollPos, &thumbPos, &thumbSize);

        int32_t sbY      = w->y + LISTVIEW_BORDER + headerH;
        int32_t relMouse = mouseY - sbY - WGT_SB_W - dragOff;
        int32_t newScroll = (trackLen > thumbSize) ? (maxScroll * relMouse) / (trackLen - thumbSize) : 0;
        lv->scrollPos = clampInt(newScroll, 0, maxScroll);
    } else if (orient == 1) {
        // Horizontal scrollbar drag
        int32_t maxScroll = totalColW - innerW;

        if (maxScroll <= 0) {
            return;
        }

        int32_t trackLen = innerW - WGT_SB_W * 2;
        int32_t thumbPos;
        int32_t thumbSize;
        widgetScrollbarThumb(trackLen, totalColW, innerW, lv->scrollPosH, &thumbPos, &thumbSize);

        int32_t sbX      = w->x + LISTVIEW_BORDER;
        int32_t relMouse = mouseX - sbX - WGT_SB_W - dragOff;
        int32_t newScroll = (trackLen > thumbSize) ? (maxScroll * relMouse) / (trackLen - thumbSize) : 0;
        lv->scrollPosH = clampInt(newScroll, 0, maxScroll);
    }
}


// ============================================================
// DXE registration
// ============================================================

// ============================================================
// widgetListViewGetCursorShape
// ============================================================

int32_t widgetListViewGetCursorShape(const WidgetT *w, int32_t vx, int32_t vy) {
    if (widgetListViewColBorderHit(w, vx, vy)) {
        return CURSOR_RESIZE_H;
    }

    return 0;
}


static void widgetListViewReorderUpdate(WidgetT *w, WidgetT *root, int32_t x, int32_t y) {
    (void)root;
    (void)x;
    ListViewDataT *lv  = (ListViewDataT *)w->data;
    AppContextT *ctx   = wgtGetContext(w);
    const BitmapFontT *font = &ctx->font;
    int32_t headerH    = font->charHeight + 4;
    int32_t dataY      = w->y + LISTVIEW_BORDER + headerH;
    int32_t relY       = y - dataY;
    int32_t dropIdx    = lv->scrollPos + relY / font->charHeight;

    if (dropIdx < 0) {
        dropIdx = 0;
    }

    if (dropIdx > lv->rowCount) {
        dropIdx = lv->rowCount;
    }

    lv->dropIdx = dropIdx;

    // Auto-scroll near edges
    int32_t innerH      = w->h - LISTVIEW_BORDER * 2 - headerH;
    int32_t visibleRows = innerH / font->charHeight;

    if (relY < font->charHeight && lv->scrollPos > 0) {
        lv->scrollPos--;
    } else if (relY >= (visibleRows - 1) * font->charHeight && lv->scrollPos < lv->rowCount - visibleRows) {
        lv->scrollPos++;
    }
}


static void widgetListViewReorderDrop(WidgetT *w) {
    ListViewDataT *lv = (ListViewDataT *)w->data;
    int32_t from      = lv->dragIdx;
    int32_t to        = lv->dropIdx;

    lv->dragIdx = -1;
    lv->dropIdx = -1;

    if (from < 0 || to < 0 || from == to || from == to - 1) {
        return;
    }

    if (from < 0 || from >= lv->rowCount) {
        return;
    }

    // Move row data by shifting the cellData pointers.
    // cellData is row-major: cellData[row * colCount + col].
    int32_t cols = lv->colCount;
    const char **moving = (const char **)malloc(cols * sizeof(const char *));

    if (!moving) {
        return;
    }

    // Save the moving row
    for (int32_t c = 0; c < cols; c++) {
        moving[c] = lv->cellData[from * cols + c];
    }

    // Save the moving row's selection bit
    uint8_t movingSel = (lv->selBits && from < lv->rowCount) ? lv->selBits[from] : 0;

    if (to > from) {
        // Moving down: shift rows up
        for (int32_t r = from; r < to - 1; r++) {
            for (int32_t c = 0; c < cols; c++) {
                ((const char **)lv->cellData)[r * cols + c] = lv->cellData[(r + 1) * cols + c];
            }

            if (lv->selBits) {
                lv->selBits[r] = lv->selBits[r + 1];
            }
        }

        for (int32_t c = 0; c < cols; c++) {
            ((const char **)lv->cellData)[(to - 1) * cols + c] = moving[c];
        }

        if (lv->selBits) {
            lv->selBits[to - 1] = movingSel;
        }

        lv->selectedIdx = to - 1;
    } else {
        // Moving up: shift rows down
        for (int32_t r = from; r > to; r--) {
            for (int32_t c = 0; c < cols; c++) {
                ((const char **)lv->cellData)[r * cols + c] = lv->cellData[(r - 1) * cols + c];
            }

            if (lv->selBits) {
                lv->selBits[r] = lv->selBits[r - 1];
            }
        }

        for (int32_t c = 0; c < cols; c++) {
            ((const char **)lv->cellData)[to * cols + c] = moving[c];
        }

        if (lv->selBits) {
            lv->selBits[to] = movingSel;
        }

        lv->selectedIdx = to;
    }

    free(moving);

    if (w->onChange) {
        w->onChange(w);
    }
}


// ============================================================
// widgetListViewOnDragEnd
// ============================================================

static void widgetListViewOnDragEnd(WidgetT *w, WidgetT *root, int32_t x, int32_t y) {
    (void)root;
    (void)x;
    (void)y;
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (lv->dragIdx >= 0) {
        widgetListViewReorderDrop(w);
        lv->dragIdx = -1;
    }

    lv->resizeDragging = false;
    wgtInvalidatePaint(w);
}


// ============================================================
// widgetListViewOnDragUpdate
// ============================================================

static void widgetListViewOnDragUpdate(WidgetT *w, WidgetT *root, int32_t x, int32_t y) {
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (lv->resizeDragging) {
        widgetListViewScrollDragUpdate(w, -1, 0, x, y);
    } else if (lv->dragIdx >= 0) {
        widgetListViewReorderUpdate(w, root, x, y);
    } else {
        widgetListViewScrollDragUpdate(w, lv->sbDragOrient, lv->sbDragOff, x, y);
    }
}


static const WidgetClassT sClassListView = {
    .version = WGT_CLASS_VERSION,
    .flags   = WCLASS_FOCUSABLE | WCLASS_NO_HIT_RECURSE | WCLASS_SCROLLABLE,
    .handlers = {
        [WGT_METHOD_PAINT]            = (void *)widgetListViewPaint,
        [WGT_METHOD_CALC_MIN_SIZE]    = (void *)widgetListViewCalcMinSize,
        [WGT_METHOD_ON_MOUSE]         = (void *)widgetListViewOnMouse,
        [WGT_METHOD_ON_KEY]           = (void *)widgetListViewOnKey,
        [WGT_METHOD_DESTROY]          = (void *)widgetListViewDestroy,
        [WGT_METHOD_GET_CURSOR_SHAPE] = (void *)widgetListViewGetCursorShape,
        [WGT_METHOD_ON_DRAG_UPDATE]   = (void *)widgetListViewOnDragUpdate,
        [WGT_METHOD_ON_DRAG_END]      = (void *)widgetListViewOnDragEnd,
    }
};


// ============================================================
// Widget creation functions and accessors
// ============================================================


WidgetT *wgtListView(WidgetT *parent) {
    WidgetT *w = widgetAlloc(parent, sTypeId);

    if (!w) {
        return NULL;
    }

    ListViewDataT *lv = (ListViewDataT *)calloc(1, sizeof(ListViewDataT));

    if (!lv) {
        free(w);
        return NULL;
    }

    lv->selectedIdx = -1;
    lv->anchorIdx   = -1;
    lv->sortCol     = -1;
    lv->sortDir     = ListViewSortNoneE;
    lv->dragIdx     = -1;
    lv->dropIdx     = -1;
    lv->resizeCol   = -1;
    w->data         = lv;
    w->weight       = 100;

    return w;
}


void wgtListViewAddItem(WidgetT *w, const char *text) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (lv->colCount <= 0) {
        return;
    }

    // If at a row boundary, add colCount empty cells to start a new row
    if (lv->nextCell % lv->colCount == 0) {
        for (int32_t c = 0; c < lv->colCount; c++) {
            arrput(lv->ownedCells, strdup(""));
        }
    }

    // Replace the next empty cell with the provided text
    int32_t idx = lv->nextCell;
    free(lv->ownedCells[idx]);
    lv->ownedCells[idx] = strdup(text ? text : "");
    lv->nextCell++;

    listViewSyncOwned(w);
}


void wgtListViewClear(WidgetT *w) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    for (int32_t i = 0; i < (int32_t)arrlen(lv->ownedCells); i++) {
        free(lv->ownedCells[i]);
    }
    arrsetlen(lv->ownedCells, 0);
    lv->nextCell    = 0;
    lv->selectedIdx = -1;
    lv->scrollPos   = 0;
    lv->scrollPosH  = 0;
    listViewSyncOwned(w);
}


void wgtListViewClearSelection(WidgetT *w) {
    if (!w || w->type != sTypeId) {
        return;
    }

    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (!lv->selBits) {
        return;
    }

    memset(lv->selBits, 0, lv->rowCount);
    wgtInvalidatePaint(w);
}


const char *wgtListViewGetCell(const WidgetT *w, int32_t row, int32_t col) {
    if (!w || w->type != sTypeId) {
        return "";
    }

    const ListViewDataT *lv = (const ListViewDataT *)w->data;

    if (row < 0 || row >= lv->rowCount || col < 0 || col >= lv->colCount) {
        return "";
    }

    const char *cell = lv->cellData[row * lv->colCount + col];
    return cell ? cell : "";
}


int32_t wgtListViewGetRowCount(const WidgetT *w) {
    if (!w || w->type != sTypeId) {
        return 0;
    }

    const ListViewDataT *lv = (const ListViewDataT *)w->data;
    return lv->rowCount;
}


int32_t wgtListViewGetSelected(const WidgetT *w) {
    VALIDATE_WIDGET(w, sTypeId, -1);
    const ListViewDataT *lv = (const ListViewDataT *)w->data;

    return lv->selectedIdx;
}


bool wgtListViewIsItemSelected(const WidgetT *w, int32_t idx) {
    VALIDATE_WIDGET(w, sTypeId, false);
    const ListViewDataT *lv = (const ListViewDataT *)w->data;

    if (!lv->multiSelect) {
        return idx == lv->selectedIdx;
    }

    if (!lv->selBits || idx < 0 || idx >= lv->rowCount) {
        return false;
    }

    return lv->selBits[idx] != 0;
}


void wgtListViewRemoveRow(WidgetT *w, int32_t row) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (row < 0 || row >= lv->rowCount || lv->colCount <= 0) {
        return;
    }

    // Remove colCount cells starting at row * colCount
    int32_t base = row * lv->colCount;

    for (int32_t c = 0; c < lv->colCount; c++) {
        free(lv->ownedCells[base + c]);
    }

    // Shift remaining cells down by colCount positions
    int32_t totalCells = (int32_t)arrlen(lv->ownedCells);

    for (int32_t i = base; i < totalCells - lv->colCount; i++) {
        lv->ownedCells[i] = lv->ownedCells[i + lv->colCount];
    }

    arrsetlen(lv->ownedCells, totalCells - lv->colCount);

    // Adjust nextCell if it was past the removed row
    if (lv->nextCell > base + lv->colCount) {
        lv->nextCell -= lv->colCount;
    } else if (lv->nextCell > base) {
        lv->nextCell = base;
    }

    listViewSyncOwned(w);

    if (lv->selectedIdx >= lv->rowCount) {
        lv->selectedIdx = lv->rowCount > 0 ? lv->rowCount - 1 : -1;
    }
}


void wgtListViewSelectAll(WidgetT *w) {
    if (!w || w->type != sTypeId) {
        return;
    }

    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (!lv->selBits) {
        return;
    }

    memset(lv->selBits, 1, lv->rowCount);
    wgtInvalidatePaint(w);
}


void wgtListViewSetCell(WidgetT *w, int32_t row, int32_t col, const char *text) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (row < 0 || row >= lv->rowCount || col < 0 || col >= lv->colCount) {
        return;
    }

    if (!lv->ownsCells) {
        return;
    }

    int32_t idx = row * lv->colCount + col;
    free(lv->ownedCells[idx]);
    lv->ownedCells[idx] = strdup(text ? text : "");

    // cellData pointer may have been invalidated by prior arrput; refresh it
    lv->cellData  = (const char **)lv->ownedCells;
    lv->totalColW = 0;
    wgtInvalidate(w);
}


void wgtListViewSetHeaderClickCallback(WidgetT *w, void (*cb)(WidgetT *w, int32_t col, ListViewSortE dir)) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    lv->onHeaderClick = cb;
}


void wgtListViewSetItemSelected(WidgetT *w, int32_t idx, bool selected) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    if (!lv->selBits || idx < 0 || idx >= lv->rowCount) {
        return;
    }

    lv->selBits[idx] = selected ? 1 : 0;
    wgtInvalidatePaint(w);
}


void wgtListViewSetSelected(WidgetT *w, int32_t idx) {
    VALIDATE_WIDGET_VOID(w, sTypeId);
    ListViewDataT *lv = (ListViewDataT *)w->data;

    lv->selectedIdx = idx;
    lv->anchorIdx   = idx;

    if (lv->selBits) {
        memset(lv->selBits, 0, lv->rowCount);

        if (idx >= 0 && idx < lv->rowCount) {
            lv->selBits[idx] = 1;
        }
    }

    wgtInvalidatePaint(w);
}


// ============================================================
// DXE registration
// ============================================================


static const struct {
    WidgetT *(*create)(WidgetT *parent);
    void     (*setColumns)(WidgetT *w, const ListViewColT *cols, int32_t count);
    void     (*setData)(WidgetT *w, const char **cellData, int32_t rowCount);
    int32_t  (*getSelected)(const WidgetT *w);
    void     (*setSelected)(WidgetT *w, int32_t idx);
    void     (*setSort)(WidgetT *w, int32_t col, ListViewSortE dir);
    void     (*setHeaderClickCallback)(WidgetT *w, void (*cb)(WidgetT *w, int32_t col, ListViewSortE dir));
    void     (*setMultiSelect)(WidgetT *w, bool multi);
    bool     (*isItemSelected)(const WidgetT *w, int32_t idx);
    void     (*setItemSelected)(WidgetT *w, int32_t idx, bool selected);
    void     (*selectAll)(WidgetT *w);
    void     (*clearSelection)(WidgetT *w);
    void     (*setReorderable)(WidgetT *w, bool reorderable);
    void     (*addItem)(WidgetT *w, const char *text);
    void     (*removeRow)(WidgetT *w, int32_t row);
    void     (*clear)(WidgetT *w);
    const char *(*getCell)(const WidgetT *w, int32_t row, int32_t col);
    void     (*setCell)(WidgetT *w, int32_t row, int32_t col, const char *text);
    int32_t  (*getRowCount)(const WidgetT *w);
} sApi = {
    .create                = wgtListView,
    .setColumns            = wgtListViewSetColumns,
    .setData               = wgtListViewSetData,
    .getSelected           = wgtListViewGetSelected,
    .setSelected           = wgtListViewSetSelected,
    .setSort               = wgtListViewSetSort,
    .setHeaderClickCallback = wgtListViewSetHeaderClickCallback,
    .setMultiSelect        = wgtListViewSetMultiSelect,
    .isItemSelected        = wgtListViewIsItemSelected,
    .setItemSelected       = wgtListViewSetItemSelected,
    .selectAll             = wgtListViewSelectAll,
    .clearSelection        = wgtListViewClearSelection,
    .setReorderable        = wgtListViewSetReorderable,
    .addItem               = wgtListViewAddItem,
    .removeRow             = wgtListViewRemoveRow,
    .clear                 = wgtListViewClear,
    .getCell               = wgtListViewGetCell,
    .setCell               = wgtListViewSetCell,
    .getRowCount           = wgtListViewGetRowCount
};

static const WgtPropDescT sProps[] = {
    { "ListIndex", WGT_IFACE_INT, (void *)wgtListViewGetSelected, (void *)wgtListViewSetSelected, NULL }
};

static const WgtMethodDescT sMethods[] = {
    { "AddItem",         WGT_SIG_STR,          (void *)wgtListViewAddItem },
    { "Clear",           WGT_SIG_VOID,         (void *)wgtListViewClear },
    { "ClearSelection",  WGT_SIG_VOID,         (void *)wgtListViewClearSelection },
    { "GetCell",         WGT_SIG_RET_STR_INT_INT,  (void *)wgtListViewGetCell },
    { "IsItemSelected",  WGT_SIG_RET_BOOL_INT, (void *)wgtListViewIsItemSelected },
    { "RemoveItem",      WGT_SIG_INT,          (void *)wgtListViewRemoveRow },
    { "RowCount",        WGT_SIG_RET_INT,      (void *)wgtListViewGetRowCount },
    { "SelectAll",       WGT_SIG_VOID,         (void *)wgtListViewSelectAll },
    { "SetCell",         WGT_SIG_INT_INT_STR,  (void *)wgtListViewSetCell },
    { "SetItemSelected", WGT_SIG_INT_BOOL,     (void *)wgtListViewSetItemSelected },
    { "SetMultiSelect",  WGT_SIG_BOOL,         (void *)wgtListViewSetMultiSelect },
    { "SetReorderable",  WGT_SIG_BOOL,         (void *)wgtListViewSetReorderable },
};

static const WgtIfaceT sIface = {
    .basName      = "ListView",
    .props        = sProps,
    .propCount    = 1,
    .methods      = sMethods,
    .methodCount  = 12,
    .events       = NULL,
    .eventCount   = 0,
    .createSig    = WGT_CREATE_PARENT,
    .defaultEvent = "Click"
};

void wgtRegister(void) {
    sTypeId = wgtRegisterClass(&sClassListView);
    wgtRegisterApi("listview", &sApi);
    wgtRegisterIface("listview", &sIface);
}