/*
 * meow_select.c — §5.8.6 枚举/预设选择器（M7.2 设置页缺口 #4）。
 *
 * 封装 = BottomSheet（标题 + 选项列表）+ meow_listview(SINGLE) 单选列表。选项用 meow_listview
 * 渲染（单选高亮 primaryContainer、可滚动 meow_scroll 惯性）；外层模态复用 meow_ui_modal_*
 * + meow_ui_modal_capture/restore（与 meow_dialog 同源：scrim 只叠一层/关闭无残影）。
 * 阻塞式（meow_input_pop 轮询）；打开前排空残留触摸；点面板外/左缘返回 = 取消；点选项 = 选中 +
 * 关闭 + on_change 回调。选项数组定长（≤MEOW_SELECT_MAX_ITEMS）。
 */
#include "meow_ui.h"
#include "include/meow_select.h"
#include "meow_ui_internal.h"   /* meow_input_pop/drain + meow_ui_modal_capture/restore */
#include <string.h>
#include <stdlib.h>
#include <unistd.h>

#define MEOW_SELECT_ROW   48   /* 选项行高（px） */

struct meow_select {
    char    title[96];
    char    items[MEOW_SELECT_MAX_ITEMS][64];
    int     nitems;
    int     cur;          /* 初始/当前选中项 */
    int     result;       /* 选中下标 / -1=取消 */
    int     done;
    int     h;            /* 面板高度（0=自动） */
    meow_select_fn cb;
    void   *ctx;
};

/* meow_listview src2 数据源：填 title=options[idx]（右尾件无；enabled=1）。 */
static int select_src2(int idx, meow_list_item *out, void *ctx)
{
    meow_select *s = (meow_select *)ctx;
    if (idx < 0 || idx >= s->nitems) return 0;
    memset(out, 0, sizeof *out);
    out->title = s->items[idx];
    out->right = MEOW_LIST_RIGHT_NONE;
    out->enabled = 1;
    return 1;
}

meow_select *meow_select_create(const char *title, int cur)
{
    meow_select *s = (meow_select *)calloc(1, sizeof *s);
    if (!s) return NULL;
    if (title) { strncpy(s->title, title, sizeof s->title - 1); s->title[sizeof s->title - 1] = '\0'; }
    s->cur = cur; s->result = -1; s->done = 0;
    return s;
}
int meow_select_add_item(meow_select *s, const char *label)
{
    if (!s || s->nitems >= MEOW_SELECT_MAX_ITEMS) return -1;
    if (label) { strncpy(s->items[s->nitems], label, 63); s->items[s->nitems][63] = '\0'; }
    int idx = s->nitems;
    s->nitems++;
    return idx;
}
void meow_select_set_on_change(meow_select *s, meow_select_fn cb, void *ctx)
{ if (s) { s->cb = cb; s->ctx = ctx; } }

int meow_select_open(meow_select *s)
{
    if (!s || s->nitems <= 0) return -1;
    const meow_theme *th = meow_theme_get();
    meow_input_start();
    meow_input_drain();          /* 排空残留触摸（goodix 长尾） */

    s->done = 0; s->result = -1;
    int W = meow_ui_width(), H = meow_ui_height();
    int sb = meow_ui_statusbar_height(); if (sb < 0) sb = 0;
    int pad = 24;
    int title_h = meow_ui_text_height(th->font_title);
    int rowh = MEOW_SELECT_ROW;
    int avail = H - sb - 20;
    int min_h = pad + title_h + 12 + rowh + 20;
    int want = (s->h > 0) ? s->h : min_h;
    int est = pad + title_h + 12 + s->nitems * rowh + 20;
    if (est > want) want = est;
    if (want > avail) want = avail;
    if (want < min_h) want = (min_h < avail) ? min_h : avail;
    int ph = want, py = H - ph;                          /* 底部面板（顶部圆角） */
    int list_y = py + pad + title_h + 12;
    int list_h = ph - (list_y - py) - pad;               /* 底部余量 */
    if (list_h < rowh) list_h = rowh;

    /* 选项列表（meow_listview[SINGLE]：单选高亮 + 可滚动）。open 时创建，close 释放（冷路径）。 */
    meow_widget *lv = meow_listview_create(0, list_y, W, list_h, s->nitems,
                                           select_src2, s, MEOW_LIST_SEL_SINGLE);
    if (!lv) return -1;
    meow_listview_set_item_h(lv, rowh);
    /* 定位初始选中项在视口内。 */
    int target = s->cur * rowh - (list_h - rowh) / 2;
    int maxs = meow_listview_max_scroll(lv);
    if (target < 0) target = 0;
    if (target > maxs) target = maxs;
    meow_listview_set_scroll(lv, target);
    meow_listview_set_sel(lv, s->cur);
    meow_scroll *sc = meow_scroll_wrap(lv, 1);           /* 惯性滚动（fling/snap） */

    /* §6.4 模态作用域 + 背景快照（关闭即还原，无残影/不叠黑）。 */
    meow_ui_modal *m = meow_ui_modal_begin();
    meow_ui_modal_capture();
    /* 首次绘制：遮罩 + 底部面板（顶部圆角）+ 标题 + 选项列表。 */
    meow_ui_fill_rect_alpha(0, 0, W, H, 0x000000, 150);
    meow_gfx_fill_round(0, py, W, ph, th->radius_card, th->surfaceContainerHighest);
    meow_ui_text(pad, py + pad, s->title, th->font_title, th->onSurface);
    meow_widget_draw(lv);
    meow_ui_flush();

    int dy_start = 0, down = 0;
    while (!s->done) {
        meow_input_ev e;
        while (meow_input_pop(&e)) {
            meow_ui_activity_ping();   /* 模态期间交互也重置息屏计时 */
            if (e.type == MEOW_EV_TOUCH_DOWN) { down = 1; dy_start = e.b; }
            else if (e.type == MEOW_EV_TOUCH_MOVE) {
                if (down && sc) {
                    meow_scroll_track(sc, e.b - dy_start, meow_ui_time_ms());
                    dy_start = e.b;
                }
            } else if (e.type == MEOW_EV_TAP) {
                int x = e.a, y = e.b;
                if (y < py) { s->done = 1; s->result = -1; break; }   /* 点面板外 = 取消 */
                int idx = meow_listview_tap_at(lv, x, y);             /* 单选高亮 = 选中 */
                if (idx >= 0) {
                    s->result = idx; s->cur = idx;
                    if (s->cb) s->cb(idx, s->ctx);                    /* 关闭即回调 */
                    s->done = 1;
                }
                /* 面板内但未命中项：保持打开（等下一次点击）。 */
            } else if (e.type == MEOW_EV_SWIPE) {
                if (e.a == MEOW_SWIPE_LEFT) { s->done = 1; s->result = -1; }   /* 返回 = 取消 */
                else if (sc) meow_scroll_fling(sc);
            }
        }
        meow_anim_tick();            /* 推进 fling */
        if (!s->done) usleep(16000);
    }
    meow_ui_modal_end(m);
    meow_ui_modal_restore();
    if (sc) meow_scroll_free(sc);
    meow_widget_free(lv);
    return s->result;
}
void meow_select_free(meow_select *s) { if (s) free(s); }

int meow_select_show(const char *title, const char *const *opts, int n, int cur)
{
    if (!opts || n <= 0) return -1;
    meow_select *s = meow_select_create(title, cur);
    if (!s) return -1;
    for (int i = 0; i < n && i < MEOW_SELECT_MAX_ITEMS; i++) meow_select_add_item(s, opts[i]);
    int r = meow_select_open(s);
    meow_select_free(s);
    return r;
}