/* bench/degrade_sim.c — song_url_auto 全档降级链离线矩阵（§20，0 真实请求）。
 *
 * 驱动真实 core/ncm_api.c 的 ncm_api_song_url_auto_f（注入假 try_fn，按「可用下限」
 * 模型应答：level <= avail_from 才给 url）。覆盖：
 *   ① desired × avail_from 全矩阵（9 档 × 9 档 + 全不可用）：命中档 = min(desired, avail_from)，
 *      请求数 = desired - 命中 + 1（逐级试，不多不少）；
 *   ② desired 越界钳制（DOLBY=16 → SURROUND；负数 → STANDARD）；
 *   ③ url 在但 type 未知（如 aac）→ 跳过继续降；
 *   ④ type 缺失时按 url 扩展名收 flac；
 *   ⑤ out_level 回填值与命中档一致（「下首恢复用户档」由调用方重传 desired 保证，
 *      链内不记忆——每次调用独立从 desired 起步）。
 *
 * 编译（宿主，ncm_app 目录下，先跑过 build_core.sh 产出 out/core-host/ 全部对象）：
 *   gcc -O2 -Wall -Wextra -DJSMN_HEADER -Icore -Ivendor/jsmn \
 *       bench/degrade_sim.c out/core-host/全部.o \
 *       -Lout/mbedtls/host -lmbedtls -lmbedx509 -lmbedcrypto -o degrade_sim -lpthread -lm
 * 运行：./degrade_sim  （PASS/FAIL 退出码）
 */
#include "ncm.h"
#include <stdio.h>
#include <string.h>

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)

/* ---- 假逐档取址：level <= g_avail_from 给 url（type 可配），记录每档请求次数 ---- */
static int g_avail_from;                 /* 可用下限；-1=全档不可用 */
static const char *g_type = "mp3";       /* 应答 type（""=缺省看扩展名） */
static const char *g_resp_level = NULL;  /* 非 NULL：响应 data[0].level 固定串（服务端静默降档模拟） */
static int g_calls[NCM_LEVEL_SURROUND + 1];

static int fake_try(const char *dev, const char *ck, const char *id, int level,
                    ncm_play_url_t *out)
{
    (void)dev; (void)ck; (void)id;
    if (level >= 0 && level <= NCM_LEVEL_SURROUND) g_calls[level]++;
    memset(out, 0, sizeof *out);
    if (level > g_avail_from) return NCM_OK;   /* 该档不可用：url 空 */
    snprintf(out->url, sizeof out->url, "http://sim/%lld.%s", (long long)12345,
             (level >= NCM_LEVEL_LOSSLESS) ? "flac" : "mp3");
    /* §2① 档位保真：无损级及以上，服务端 encodeType=flac → 应答 type=flac（真实）；g_type=""
     * （缺失）时保留空串，交给 level_attempt 按 url 扩展名推断（测试该推断路径）。 */
    if (level >= NCM_LEVEL_LOSSLESS && g_type[0])
        snprintf(out->type, sizeof out->type, "flac");
    else
        snprintf(out->type, sizeof out->type, "%s", g_type);
    if (g_resp_level) snprintf(out->level, sizeof out->level, "%s", g_resp_level);
    out->br = 320000;
    out->size = 9000000;
    return NCM_OK;
}

static int g_bad_type_from = -1;         /* >=0: 该档以上给 aac（未知格式应跳过） */
static int fake_try_badtype(const char *dev, const char *ck, const char *id, int level,
                            ncm_play_url_t *out)
{
    int r = fake_try(dev, ck, id, level, out);
    if (r == NCM_OK && out->url[0] && level >= g_bad_type_from)
        snprintf(out->type, sizeof out->type, "aac");
    return r;
}

static void reset_calls(void) { memset(g_calls, 0, sizeof g_calls); }
static int total_calls(void)
{
    int n = 0;
    for (int i = 0; i <= NCM_LEVEL_SURROUND; i++) n += g_calls[i];
    return n;
}

/* ---- §20.3 账户/fee 感知降级链（auto_av_f）期望模型 ----
 * cap(vip)：NONE→EXHIGH / CVIP→HIRES / SVIP→SURROUND（与 account.c account_level_cap 同口径）。
 * start = clamp(desired, STANDARD, cap)；只试 gate(lv)<=vip 的档；落在 lv<=avail 的最近可用档。 */
static int cap_for_vip(int vip) {
    switch (vip) {
        case NCM_VIP_SVIP: return NCM_LEVEL_SURROUND;
        case NCM_VIP_CVIP: return NCM_LEVEL_HIRES;
        default:           return NCM_LEVEL_EXHIGH;
    }
}
static int expect_land(int vip, int desired, int avail) {
    int cap = cap_for_vip(vip);
    int start = desired > cap ? cap : desired;
    if (start < NCM_LEVEL_STANDARD) start = NCM_LEVEL_STANDARD;
    for (int lv = start; lv >= NCM_LEVEL_STANDARD; lv--)
        if (ncm_api_level_gate(lv) <= vip && lv <= avail) return lv;
    return -1;
}
static int expect_tried(int vip, int desired, int best) {
    int cap = cap_for_vip(vip);
    int start = desired > cap ? cap : desired;
    if (start < NCM_LEVEL_STANDARD) start = NCM_LEVEL_STANDARD;
    int n = 0;
    for (int lv = start; lv >= NCM_LEVEL_STANDARD; lv--)
        if (ncm_api_level_gate(lv) <= vip && (best < 0 || lv >= best)) n++;
    return n;
}

int main(void)
{
    ncm_play_url_t u;
    int eff;

    printf("== 1) desired × avail_from 全矩阵 ==\n");
    int cases = 0, bad = 0;
    for (int desired = NCM_LEVEL_STANDARD; desired <= NCM_LEVEL_SURROUND; desired++) {
        for (int avail = NCM_LEVEL_STANDARD; avail <= NCM_LEVEL_SURROUND; avail++) {
            reset_calls();
            g_avail_from = avail; g_type = "mp3";
            int rc = ncm_api_song_url_auto_f("dev", "ck", "1", desired, &u, &eff, fake_try);
            int want = (avail < desired) ? avail : desired;   /* 期望命中 = min */
            int ok = (rc == NCM_OK) && (eff == want) && u.url[0] &&
                     (total_calls() == desired - want + 1);
            /* 高档（>命中）各恰好 1 次，低档不请求 */
            for (int lv = want + 1; lv <= desired; lv++) ok = ok && (g_calls[lv] == 1);
            for (int lv = 0; lv < want; lv++) ok = ok && (g_calls[lv] == 0);
            cases++;
            if (!ok) {
                bad++;
                printf("  FAIL  desired=%d(%s) avail=%d -> rc=%d eff=%d calls=%d (want %d/%d)\n",
                       desired, ncm_api_level_str(desired), avail, rc, eff, total_calls(),
                       want, desired - want + 1);
                g_fail = 1;
            }
        }
        /* 全不可用 → NOTFOUND，且恰好 desired+1 次请求 */
        reset_calls();
        g_avail_from = -1; g_type = "mp3";
        int rc = ncm_api_song_url_auto_f("dev", "ck", "1", desired, &u, &eff, fake_try);
        int ok = (rc == NCM_ERR_NOTFOUND) && (eff == -1) &&
                 (total_calls() == desired - NCM_LEVEL_STANDARD + 1);
        cases++;
        if (!ok) {
            bad++;
            printf("  FAIL  desired=%d all-unavail -> rc=%d eff=%d calls=%d\n",
                   desired, rc, eff, total_calls());
            g_fail = 1;
        }
    }
    CHECK(bad == 0, "matrix %d cases all pass (desired 9 x avail 9 + 全不可用 9)", cases);

    printf("== 2) desired 越界钳制 ==\n");
    reset_calls();
    g_avail_from = NCM_LEVEL_SURROUND; g_type = "mp3";
    CHECK(ncm_api_song_url_auto_f("d", "c", "1", NCM_LEVEL_DOLBY, &u, &eff, fake_try) == NCM_OK &&
          eff == NCM_LEVEL_SURROUND && total_calls() == 1 && g_calls[NCM_LEVEL_SURROUND] == 1,
          "desired=DOLBY(16) clamped to SURROUND (eff=%d calls=%d)", eff, total_calls());
    reset_calls();
    CHECK(ncm_api_song_url_auto_f("d", "c", "1", -7, &u, &eff, fake_try) == NCM_OK &&
          eff == NCM_LEVEL_STANDARD && total_calls() == 1,
          "desired=-7 clamped to STANDARD (eff=%d)", eff);

    printf("== 3) 未知 type 跳过继续降 ==\n");
    reset_calls();
    g_avail_from = NCM_LEVEL_SURROUND; g_bad_type_from = NCM_LEVEL_HIRES;
    /* hires 及以上 url 在但 type=aac → 跳过，落在 lossless */
    CHECK(ncm_api_song_url_auto_f("d", "c", "1", NCM_LEVEL_SKY, &u, &eff, fake_try_badtype)
              == NCM_OK && eff == NCM_LEVEL_LOSSLESS,
          "aac above hires -> land lossless (eff=%d)", eff);

    printf("== 4) type 缺失按 url 扩展名收 flac ==\n");
    reset_calls();
    g_avail_from = NCM_LEVEL_LOSSLESS; g_type = "";
    CHECK(ncm_api_song_url_auto_f("d", "c", "1", NCM_LEVEL_LOSSLESS, &u, &eff, fake_try)
              == NCM_OK && strcmp(u.type, "flac") == 0,
          "type empty + .flac url -> type backfilled flac");

    printf("== 5) out_level 每次独立（下首恢复用户档语义） ==\n");
    reset_calls();
    g_avail_from = NCM_LEVEL_STANDARD; g_type = "mp3";
    ncm_api_song_url_auto_f("d", "c", "1", NCM_LEVEL_SURROUND, &u, &eff, fake_try);
    int first_eff = eff;
    reset_calls();
    g_avail_from = NCM_LEVEL_SURROUND;
    ncm_api_song_url_auto_f("d", "c", "2", NCM_LEVEL_SURROUND, &u, &eff, fake_try);
    CHECK(first_eff == NCM_LEVEL_STANDARD && eff == NCM_LEVEL_SURROUND,
          "prev degraded to standard, next song back at surround (eff %d -> %d)",
          first_eff, eff);

    printf("== 6) 响应 level 静默降档采信（data[0].level < 请求档） ==\n");
    reset_calls();
    g_avail_from = NCM_LEVEL_SURROUND; g_type = "flac"; g_resp_level = "exhigh";
    CHECK(ncm_api_song_url_auto_f("d", "c", "1", NCM_LEVEL_HIRES, &u, &eff, fake_try) == NCM_OK &&
          eff == NCM_LEVEL_EXHIGH,
          "req hires, resp level=exhigh -> eff=exhigh (got %d)", eff);
    reset_calls();
    g_resp_level = "sky";   /* sky 族有歧义：不采信，保守取请求档 */
    CHECK(ncm_api_song_url_auto_f("d", "c", "1", NCM_LEVEL_SURROUND, &u, &eff, fake_try) == NCM_OK &&
          eff == NCM_LEVEL_SURROUND,
          "req surround, resp level=sky (歧义) -> eff=surround (got %d)", eff);
    g_resp_level = NULL;

    printf("== 7) auto_av_f fee 门禁（§20.4：fee∈{1,4} 且非 CVIP → 零请求 NCM_ERR_VIP）==\n");
    reset_calls(); g_avail_from = NCM_LEVEL_SURROUND; g_type = "mp3";
    CHECK(ncm_api_song_url_auto_av_f("d", "c", "1", NCM_VIP_NONE, 1, NCM_LEVEL_HIRES, &u, &eff, fake_try)
              == NCM_ERR_VIP && total_calls() == 0,
          "fee=1 + NONE -> NCM_ERR_VIP (calls=%d)", total_calls());
    CHECK(ncm_api_song_url_auto_av_f("d", "c", "1", NCM_VIP_NONE, 4, NCM_LEVEL_HIRES, &u, &eff, fake_try)
              == NCM_ERR_VIP && total_calls() == 0,
          "fee=4 + NONE -> NCM_ERR_VIP (calls=%d)", total_calls());
    CHECK(ncm_api_song_url_auto_av_f("d", "c", "1", NCM_VIP_CVIP, 1, NCM_LEVEL_HIRES, &u, &eff, fake_try)
              == NCM_OK, "fee=1 + CVIP -> 放行");
    CHECK(ncm_api_song_url_auto_av_f("d", "c", "1", NCM_VIP_NONE, 8, NCM_LEVEL_HIRES, &u, &eff, fake_try)
              == NCM_OK, "fee=8 + NONE -> 放行（免费听低音质）");
    CHECK(ncm_api_song_url_auto_av_f("d", "c", "1", NCM_VIP_NONE, 0, NCM_LEVEL_HIRES, &u, &eff, fake_try)
              == NCM_OK, "fee=0 + NONE -> 放行");

    printf("== 8) auto_av_f 全矩阵: account_vip 3 x desired 9 x avail 9（钳顶+门槛+最近可用档）==\n");
    int av_bad = 0, av_cases = 0;
    for (int vip = NCM_VIP_NONE; vip <= NCM_VIP_SVIP; vip++) {
        for (int desired = NCM_LEVEL_STANDARD; desired <= NCM_LEVEL_SURROUND; desired++) {
            for (int avail = NCM_LEVEL_STANDARD; avail <= NCM_LEVEL_SURROUND; avail++) {
                reset_calls();
                g_avail_from = avail; g_type = "mp3";
                int rc = ncm_api_song_url_auto_av_f("dev", "ck", "1", vip, 0, desired, &u, &eff, fake_try);
                int want = expect_land(vip, desired, avail);
                int ok = (want >= 0 && rc == NCM_OK && eff == want && u.url[0] &&
                          total_calls() == expect_tried(vip, desired, want));
                av_cases++;
                if (!ok) {
                    av_bad++;
                    printf("  FAIL  vip=%d desired=%d(%s) avail=%d -> rc=%d eff=%d calls=%d (want %d/%d)\n",
                           vip, desired, ncm_api_level_str(desired), avail, rc, eff, total_calls(),
                           want, expect_tried(vip, desired, want));
                    g_fail = 1;
                }
            }
        }
    }
    CHECK(av_bad == 0, "auto_av matrix %d cases all pass (vip 3 x desired 9 x avail 9)", av_cases);

    printf("== 9) 真机场景复现：CVIP + 设置Hi-Res + 歌曲「有SQ无Hi-Res」→ 落无损SQ ==\n");
    reset_calls();
    g_avail_from = NCM_LEVEL_LOSSLESS;   /* 歌曲只提供到 SQ（及更低）→ 无 Hi-Res */
    g_type = "flac";                     /* SQ 以 flac 下发 */
    int rc9 = ncm_api_song_url_auto_av_f("d", "c", "10", NCM_VIP_CVIP, 0, NCM_LEVEL_HIRES,
                                         &u, &eff, fake_try);
    CHECK(rc9 == NCM_OK && eff == NCM_LEVEL_LOSSLESS && strcmp(u.type, "flac") == 0,
          "CVIP Hi-Res、有SQ无HiRes -> 落无损SQ (rc=%d eff=%d(%s) type=%s)",
          rc9, eff, ncm_api_level_str(eff), u.type);
    /* 对照：若账户VIP态未就绪(NONE)，钳顶把Hi-Res压到极高，SQ被跳过（旧app clamp即此路径） */
    reset_calls();
    g_avail_from = NCM_LEVEL_LOSSLESS; g_type = "flac";
    int rcn = ncm_api_song_url_auto_av_f("d", "c", "10", NCM_VIP_NONE, 0, NCM_LEVEL_HIRES,
                                         &u, &eff, fake_try);
    CHECK(rcn == NCM_OK && eff == NCM_LEVEL_EXHIGH,
          "NONE+Hi-Res -> 钳到极高EXHIGH (rc=%d eff=%d) — 旧app clamp正是此路径致SQ被跳过",
          rcn, eff);

    printf(g_fail ? "== DEGRADE SIM: FAIL ==\n" : "== DEGRADE SIM: ALL PASS ==\n");
    return g_fail;
}