/* bench/window_sim.c — 三期第三批 滑动窗口 6000 首滚动全程离线验证（0 网络请求）。
 *
 * 驱动真实 appstate.c（滑动窗口）+ 真实 songmeta.c（盘缓存，/tmp 临时目录），
 * 网络端点（ncm_api_playlist_detail / ncm_api_song_detail）为本地合成 stub。
 * 场景（对齐用户「我喜欢」6000+ 首）：
 *   ① 重头：detail 取全量 6000 trackIds，物化首段（1 detail + 1 song_detail 批）；
 *   ② 全程下滚：视口 12 行、步进 8 行（模拟跟手拖动），每步 pl_maybe_ensure 等价物
 *      ensure(pos-24, pos+36)；每步断言视口 12 行全部物化（列表无占位破窗）；
 *      断言 song_detail 调用数 ≈ 6000/批网格（批对齐预取，无小请求放大）；
 *   ③ 全程回滚到 0：盘缓存（songmeta）全命中，song_detail 调用数 0 增长；
 *   ④ 播放兼容：窗口感知的取歌——播放线程路径 appstate_song_fetch 在窗口远离时
 *      仍能物化当前播放曲（不滑窗、不崩、盘缓存命中免请求）；
 *   ⑤ 尾部/越界：ensure 尾部区间 + 越过尾部无操作；
 *   ⑥ 内存账：6000 首场景改前（1000 截断 × 1324B）vs 改后（窗口 256×608B + 索引）。
 * 风控纪律：0 次真实 NCM 请求（离线 stub + /tmp 盘缓存）。
 *
 * 编译（宿主）：$CC_HOST -O2 -ffunction-sections -DJSMN_HEADER -I. -I../sdk -I../meow_launcherd \
 *      -Icore -I../vendor/jsmn -c bench/window_sim.c -o /tmp/ws.o
 *      $CC_HOST -O2 -ffunction-sections -DJSMN_HEADER -I. -I../sdk -I../meow_launcherd \
 *      -Icore -I../vendor/jsmn -c app/logic/appstate.c -o /tmp/ws_app.o
 *      $CC_HOST -O2 -ffunction-sections -DJSMN_HEADER -I. -I../sdk -I../meow_launcherd \
 *      -Icore -I../vendor/jsmn -c app/logic/songmeta.c -o /tmp/ws_meta.o
 *      $CC_HOST -O2 -Wl,--gc-sections -o window_sim /tmp/ws.o /tmp/ws_app.o /tmp/ws_meta.o -lpthread
 * 运行：./window_sim  （0 网络；PASS/FAIL 退出码）
 */
#include "../app/ncm_app_internal.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

ncm_app_state_t g_st;
ncm_play_run_t  g_play = { .mu = PTHREAD_MUTEX_INITIALIZER, .state = NCM_PC_STOPPED, .cur_song = -1 };
volatile int g_app_quit = 0;
volatile int g_net_ready = 0;
int          g_host_mock = 0;

size_t ncm_strlcpy(char *dst, const char *src, size_t sz)
{
    size_t n = 0;
    if (sz) {
        while (src[n] && n < sz - 1) { dst[n] = src[n]; n++; }
        dst[n] = 0;
    }
    while (src[n]) n++;
    return n;
}

/* ---- 网络端点 stub（离线，合成数据） ---- */
#define SIM_TOTAL 6000
static int g_detail_calls;
static int g_song_calls;
static int g_song_served;    /* song_detail 累计返回首数 */

int ncm_api_playlist_detail(const char *device_id, const char *cookie, const char *playlist_id,
                            char *name, size_t name_sz, char *cover, size_t cover_sz,
                            int64_t *ids, int id_cap, int *out_id_n)
{
    (void)device_id; (void)cookie; (void)cover_sz; (void)playlist_id;
    g_detail_calls++;
    if (name) snprintf(name, name_sz, "Sim Playlist");
    if (cover) cover[0] = 0;
    int n = (SIM_TOTAL < id_cap) ? SIM_TOTAL : id_cap;
    for (int i = 0; i < n; i++) ids[i] = 2000000LL + i;
    *out_id_n = n;
    return NCM_OK;
}

int ncm_api_song_detail(const char *device_id, const char *cookie, const int64_t *ids, int n,
                        ncm_song_t *out, int max, int *out_n)
{
    (void)device_id; (void)cookie;
    g_song_calls++;
    int m = (n < max) ? n : max;
    g_song_served += m;
    for (int i = 0; i < m; i++) {
        snprintf(out[i].id, sizeof out[i].id, "%lld", (long long)ids[i]);
        snprintf(out[i].name, sizeof out[i].name, "Song%lld", (long long)ids[i]);
        snprintf(out[i].art_name, sizeof out[i].art_name, "Artist%lld", (long long)ids[i]);
        snprintf(out[i].album_name, sizeof out[i].album_name, "Album%lld", (long long)ids[i]);
        snprintf(out[i].al_pic, sizeof out[i].al_pic, "http://p.music.126.net/cov%lld.jpg", (long long)ids[i]);
        out[i].duration_ms = 200000;
    }
    *out_n = m;
    return NCM_OK;
}

static int g_fail = 0;
#define CHECK(cond, fmt, ...) do { \
    if (cond) printf("  PASS  " fmt "\n", ##__VA_ARGS__); \
    else { printf("  FAIL  " fmt "\n", ##__VA_ARGS__); g_fail = 1; } \
} while (0)

/* 模拟 playlist.c pl_maybe_ensure：视口 12 行 ±24 行余量。 */
static int ui_ensure(int pos)
{
    int lo = pos - 24, hi = pos + 12 + 24;
    if (lo < 0) lo = 0;
    if (hi > SIM_TOTAL) hi = SIM_TOTAL;
    if (lo >= hi) return NCM_OK;
    if (appstate_range_loaded(lo, hi)) return NCM_OK;
    return appstate_song_ensure_range(lo, hi);
}

int main(void)
{
    if (system("rm -rf /tmp/ncm_window_sim_cache") != 0) {   /* 清上次运行残留（盘缓存） */
        printf("FAIL  cannot clean /tmp cache dir\n");
        return 1;
    }
    memset(&g_st, 0, sizeof g_st);
    snprintf(g_st.cache_dir, sizeof g_st.cache_dir, "/tmp/ncm_window_sim_cache");
    g_st.playlist_count = 1;
    snprintf(g_st.playlists[0].id, sizeof g_st.playlists[0].id, "pl6000");
    g_st.playlists[0].track_count = SIM_TOTAL;

    size_t win_bytes  = sizeof g_st.songs + sizeof g_st.song_valid;
    size_t idx_bytes  = sizeof g_st.song_ids;
    size_t old_bytes  = (size_t)1000 * 1324;             /* §14：NCM_SONG_MAX=1000 × ~1324B/首 */
    printf("== memory model ==\n");
    printf("  ncm_song_t=%zuB (old 1324B)  window=%zuB(%d首)  trackIds idx=%zuB(%d首)\n",
           sizeof(ncm_song_t), win_bytes, NCM_SONG_WINDOW, idx_bytes, NCM_TRACKID_MAX);
    printf("  6000首场景：旧模型 %zuKB（且 1000 截断）→ 新模型 %zuKB（任意长度恒定）\n",
           old_bytes / 1024, (win_bytes + idx_bytes) / 1024);

    /* ① 重头 */
    printf("== phase 1: open 6000-song playlist ==\n");
    int rc = appstate_load_playlist_songs_page(0, 0, NCM_SONG_BATCH);
    CHECK(rc == NCM_OK, "page0 rc=%d", rc);
    CHECK(g_st.track_ids_count == SIM_TOTAL, "track_ids_count=%d (expect %d, 无截断)",
          g_st.track_ids_count, SIM_TOTAL);
    CHECK(g_st.song_count == NCM_SONG_BATCH, "valid slots=%d (expect first batch %d)",
          g_st.song_count, NCM_SONG_BATCH);
    CHECK(g_st.window_base == 0, "window_base=%d", g_st.window_base);
    CHECK(g_detail_calls == 1 && g_song_calls == 1, "detail=%d song_detail=%d (expect 1+1)",
          g_detail_calls, g_song_calls);

    /* ② 全程下滚（0→6000，步进 8 行）：视口每步全部物化 */
    printf("== phase 2: scroll down 0 -> %d (step 8 rows) ==\n", SIM_TOTAL);
    int step_checks = 0;
    for (int pos = 0; pos < SIM_TOTAL; pos += 8) {
        rc = ui_ensure(pos);
        if (rc != NCM_OK) { printf("  FAIL  ensure(pos=%d) rc=%d\n", pos, rc); g_fail = 1; break; }
        int vhi = pos + 12; if (vhi > SIM_TOTAL) vhi = SIM_TOTAL;
        if (!appstate_range_loaded(pos, vhi)) {
            printf("  FAIL  viewport [%d,%d) not fully materialized\n", pos, vhi);
            g_fail = 1; break;
        }
        step_checks++;
    }
    CHECK(step_checks == (SIM_TOTAL + 7) / 8, "scroll steps verified=%d (expect %d)",
          step_checks, (SIM_TOTAL + 7) / 8);
    CHECK(g_st.song_count <= NCM_SONG_WINDOW, "valid slots=%d ≤ window %d (全程不超窗)",
          g_st.song_count, NCM_SONG_WINDOW);
    printf("  INFO  song_detail calls=%d served=%d (grid prefetch; 下限 %d)\n",
           g_song_calls, g_song_served, SIM_TOTAL / NCM_SONG_BATCH);
    CHECK(g_song_calls <= SIM_TOTAL / NCM_SONG_BATCH + 6,
          "song_detail calls=%d ≤ %d (批网格对齐，无小请求放大)",
          g_song_calls, SIM_TOTAL / NCM_SONG_BATCH + 6);
    ncm_song_t sq;
    CHECK(appstate_song_copy(SIM_TOTAL - 1, &sq) == 0 &&
          strcmp(sq.name, "Song2005999") == 0, "tail song name='%s'", sq.name);
    CHECK(appstate_song_copy(0, &sq) != 0, "head evicted after scrolling to tail");

    /* ③ 全程回滚到 0：盘缓存全命中，0 新增 song_detail */
    printf("== phase 3: scroll back up %d -> 0 (disk cache) ==\n", SIM_TOTAL);
    int calls_before = g_song_calls;
    step_checks = 0;
    for (int pos = SIM_TOTAL - 8; pos >= 0; pos -= 8) {
        rc = ui_ensure(pos);
        if (rc != NCM_OK) { printf("  FAIL  ensure(pos=%d) rc=%d\n", pos, rc); g_fail = 1; break; }
        int vhi = pos + 12; if (vhi > SIM_TOTAL) vhi = SIM_TOTAL;
        if (!appstate_range_loaded(pos, vhi)) {
            printf("  FAIL  viewport [%d,%d) not materialized on way back\n", pos, vhi);
            g_fail = 1; break;
        }
        step_checks++;
    }
    CHECK(g_song_calls == calls_before,
          "scroll-back song_detail calls +%d (expect 0，盘缓存全命中)", g_song_calls - calls_before);
    CHECK(appstate_song_copy(0, &sq) == 0 && strcmp(sq.name, "Song2000000") == 0,
          "head re-materialized from disk: name='%s'", sq.name);

    /* ④ 播放兼容：窗口滑出当前播放曲 → fetch 不滑窗、不崩、盘命中免请求 */
    printf("== phase 4: playback survives window slide ==\n");
    rc = appstate_song_ensure_range(3000 - 128, 3000 + 128);   /* 窗口移到 3000 附近 */
    int base_at_play = g_st.window_base;
    CHECK(rc == NCM_OK, "ensure around 3000 rc=%d", rc);
    /* 模拟 run_song：cur=3050 在窗内 → song_copy；然后窗口滑回 0，再 fetch(3050) */
    CHECK(appstate_song_copy(3050, &sq) == 0, "song_copy(3050) in window");
    rc = appstate_song_ensure_range(0, 100);                    /* 用户滚回顶部（窗口滑走） */
    CHECK(rc == NCM_OK && g_st.window_base != base_at_play,
          "window slid away base %d -> %d", base_at_play, g_st.window_base);
    CHECK(appstate_song_copy(3050, &sq) != 0, "playing song evicted from window");
    calls_before = g_song_calls;
    rc = appstate_song_fetch(3050, &sq);                        /* 播放线程路径：不滑窗 */
    CHECK(rc == NCM_OK && strcmp(sq.id, "2003050") == 0 && sq.duration_ms == 200000,
          "fetch(3050) ok id=%s dur=%d", sq.id, sq.duration_ms);
    CHECK(g_st.window_base != base_at_play && g_st.song_count <= NCM_SONG_WINDOW,
          "fetch did not move window (base=%d)", g_st.window_base);
    CHECK(g_song_calls == calls_before, "fetch hit disk cache (0 new requests)");
    /* next/prev 边界语义：cur 可到 SIM_TOTAL-1，不越界不崩 */
    CHECK(appstate_song_fetch(SIM_TOTAL - 1, &sq) == NCM_OK, "fetch(tail) ok");
    CHECK(appstate_song_fetch(SIM_TOTAL, &sq) != NCM_OK, "fetch(out of range) rejected");

    /* ⑤ 尾部/越界 ensure */
    printf("== phase 5: tail & out-of-range ==\n");
    rc = appstate_song_ensure_range(SIM_TOTAL - 12, SIM_TOTAL);
    CHECK(rc == NCM_OK && appstate_range_loaded(SIM_TOTAL - 12, SIM_TOTAL),
          "tail ensure rc=%d", rc);
    CHECK(g_st.window_base <= SIM_TOTAL - NCM_SONG_WINDOW ||
          SIM_TOTAL < NCM_SONG_WINDOW, "base=%d clamped at tail", g_st.window_base);
    rc = appstate_song_ensure_range(SIM_TOTAL, SIM_TOTAL + 100);
    CHECK(rc == NCM_OK, "ensure past tail no-op rc=%d", rc);
    rc = appstate_song_ensure_range(-50, 0);
    CHECK(rc == NCM_OK, "ensure empty range no-op rc=%d", rc);

    /* ⑥ 盘缓存规模核对 */
    printf("== phase 6: disk cache ==\n");
    {
        char cmd[256];
        snprintf(cmd, sizeof cmd,
                 "ls /tmp/ncm_window_sim_cache/meta | wc -l");
        FILE *p = popen(cmd, "r");
        int files = -1;
        if (p) { if (fscanf(p, "%d", &files) != 1) files = -1; pclose(p); }
        CHECK(files == SIM_TOTAL, "songmeta files=%d (expect %d, 全程拉过即落盘)", files, SIM_TOTAL);
    }

    printf("%s\n", g_fail ? "RESULT: FAIL" : "RESULT: PASS");
    return g_fail ? 1 : 0;
}