// widgetTabControl.c — TabControl and TabPage widgets

#include "widgetInternal.h"


// ============================================================
// wgtTabControl
// ============================================================

WidgetT *wgtTabControl(WidgetT *parent) {
    WidgetT *w = widgetAlloc(parent, WidgetTabControlE);

    if (w) {
        w->as.tabControl.activeTab = 0;
        w->weight = 100;
    }

    return w;
}


// ============================================================
// wgtTabControlGetActive
// ============================================================

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

    return w->as.tabControl.activeTab;
}


// ============================================================
// wgtTabControlSetActive
// ============================================================

void wgtTabControlSetActive(WidgetT *w, int32_t idx) {
    if (!w || w->type != WidgetTabControlE) {
        return;
    }

    w->as.tabControl.activeTab = idx;
}


// ============================================================
// wgtTabPage
// ============================================================

WidgetT *wgtTabPage(WidgetT *parent, const char *title) {
    WidgetT *w = widgetAlloc(parent, WidgetTabPageE);

    if (w) {
        w->as.tabPage.title = title;
    }

    return w;
}


// ============================================================
// widgetTabControlCalcMinSize
// ============================================================

void widgetTabControlCalcMinSize(WidgetT *w, const BitmapFontT *font) {
    int32_t tabH       = font->charHeight + TAB_PAD_V * 2;
    int32_t maxPageW   = 0;
    int32_t maxPageH   = 0;
    int32_t tabHeaderW = 0;

    for (WidgetT *c = w->firstChild; c; c = c->nextSibling) {
        if (c->type != WidgetTabPageE) {
            continue;
        }

        widgetCalcMinSizeTree(c, font);
        maxPageW = DVX_MAX(maxPageW, c->calcMinW);
        maxPageH = DVX_MAX(maxPageH, c->calcMinH);

        int32_t labelW = (int32_t)strlen(c->as.tabPage.title) * font->charWidth + TAB_PAD_H * 2;
        tabHeaderW += labelW;
    }

    w->calcMinW = DVX_MAX(maxPageW + TAB_BORDER * 2, tabHeaderW);
    w->calcMinH = tabH + maxPageH + TAB_BORDER * 2;
}


// ============================================================
// widgetTabControlLayout
// ============================================================

void widgetTabControlLayout(WidgetT *w, const BitmapFontT *font) {
    int32_t tabH     = font->charHeight + TAB_PAD_V * 2;
    int32_t contentX = w->x + TAB_BORDER;
    int32_t contentY = w->y + tabH + TAB_BORDER;
    int32_t contentW = w->w - TAB_BORDER * 2;
    int32_t contentH = w->h - tabH - TAB_BORDER * 2;

    if (contentW < 0) { contentW = 0; }
    if (contentH < 0) { contentH = 0; }

    int32_t idx = 0;

    for (WidgetT *c = w->firstChild; c; c = c->nextSibling) {
        if (c->type != WidgetTabPageE) {
            continue;
        }

        c->x = contentX;
        c->y = contentY;
        c->w = contentW;
        c->h = contentH;

        // Only layout the active page
        if (idx == w->as.tabControl.activeTab) {
            widgetLayoutChildren(c, font);
        }

        idx++;
    }
}


// ============================================================
// widgetTabControlOnMouse
// ============================================================

void widgetTabControlOnMouse(WidgetT *hit, WidgetT *root, int32_t vx, int32_t vy) {
    AppContextT *ctx = (AppContextT *)root->userData;
    const BitmapFontT *font = &ctx->font;
    int32_t tabH = font->charHeight + TAB_PAD_V * 2;

    // Only handle clicks in the tab header area
    if (vy >= hit->y && vy < hit->y + tabH) {
        int32_t tabX   = hit->x + 2;
        int32_t tabIdx = 0;

        for (WidgetT *c = hit->firstChild; c; c = c->nextSibling) {
            if (c->type != WidgetTabPageE) {
                continue;
            }

            int32_t tw = (int32_t)strlen(c->as.tabPage.title) * font->charWidth + TAB_PAD_H * 2;

            if (vx >= tabX && vx < tabX + tw) {
                if (tabIdx != hit->as.tabControl.activeTab) {
                    hit->as.tabControl.activeTab = tabIdx;

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

                break;
            }

            tabX += tw;
            tabIdx++;
        }
    }
}


// ============================================================
// widgetTabControlPaint
// ============================================================

void widgetTabControlPaint(WidgetT *w, DisplayT *d, const BlitOpsT *ops, const BitmapFontT *font, const ColorSchemeT *colors) {
    int32_t tabH = font->charHeight + TAB_PAD_V * 2;

    // Content panel
    BevelStyleT panelBevel;
    panelBevel.highlight = colors->windowHighlight;
    panelBevel.shadow    = colors->windowShadow;
    panelBevel.face      = colors->contentBg;
    panelBevel.width     = 2;
    drawBevel(d, ops, w->x, w->y + tabH, w->w, w->h - tabH, &panelBevel);

    // Tab headers
    int32_t tabX   = w->x + 2;
    int32_t tabIdx = 0;

    for (WidgetT *c = w->firstChild; c; c = c->nextSibling) {
        if (c->type != WidgetTabPageE) {
            continue;
        }

        int32_t  tw       = (int32_t)strlen(c->as.tabPage.title) * font->charWidth + TAB_PAD_H * 2;
        bool     isActive = (tabIdx == w->as.tabControl.activeTab);
        int32_t  ty       = isActive ? w->y : w->y + 2;
        int32_t  th       = isActive ? tabH + 2 : tabH;
        uint32_t tabFace  = isActive ? colors->contentBg : colors->windowFace;

        // Fill tab background
        rectFill(d, ops, tabX + 2, ty + 2, tw - 4, th - 2, tabFace);

        // Top edge
        drawHLine(d, ops, tabX + 2, ty, tw - 4, colors->windowHighlight);
        drawHLine(d, ops, tabX + 2, ty + 1, tw - 4, colors->windowHighlight);

        // Left edge
        drawVLine(d, ops, tabX, ty + 2, th - 2, colors->windowHighlight);
        drawVLine(d, ops, tabX + 1, ty + 2, th - 2, colors->windowHighlight);

        // Right edge
        drawVLine(d, ops, tabX + tw - 1, ty + 2, th - 2, colors->windowShadow);
        drawVLine(d, ops, tabX + tw - 2, ty + 2, th - 2, colors->windowShadow);

        if (isActive) {
            // Erase panel top border under active tab
            rectFill(d, ops, tabX + 2, w->y + tabH, tw - 4, 2, colors->contentBg);
        } else {
            // Bottom edge for inactive tab
            drawHLine(d, ops, tabX, ty + th - 1, tw, colors->windowShadow);
            drawHLine(d, ops, tabX + 1, ty + th - 2, tw - 2, colors->windowShadow);
        }

        // Tab label
        int32_t labelY = ty + TAB_PAD_V;

        if (!isActive) {
            labelY++;
        }

        drawText(d, ops, font, tabX + TAB_PAD_H, labelY,
                 c->as.tabPage.title, colors->contentFg, tabFace, true);

        tabX += tw;
        tabIdx++;
    }

    // Paint only active tab page's children
    tabIdx = 0;

    for (WidgetT *c = w->firstChild; c; c = c->nextSibling) {
        if (c->type != WidgetTabPageE) {
            continue;
        }

        if (tabIdx == w->as.tabControl.activeTab) {
            for (WidgetT *gc = c->firstChild; gc; gc = gc->nextSibling) {
                widgetPaintOne(gc, d, ops, font, colors);
            }

            break;
        }

        tabIdx++;
    }
}