/* bench/player_flow_sim.c — 播放线程状态机离线回归（0 真实请求，REPORT §18）。
 *
 * 驱动真实 app/play/player_manager.c（外层 player_thread + run_song 全链路），
 * 解码器/音频输出/网络/缓存全部本地 stub（可注入：写失败、url 失败、慢下载）。
 *
 * 用例：
 *   P1 自然播完 → 自动顺延下一首（曲终不停在原地，err=0）；
 *   P2 音频写失败（流死/audiod 断链）→ **置错停播，cur_song 不动**——§18 前静默 break
 *      被外层当「自然播完」连环跳歌+狂发 song_url（本用例在旧代码上 FAIL）；
 *   P3 song_url 无音源 → STOPPED + NCM_ERR_NOTFOUND + errmsg（UI 有错误可显示）；
 *   P4 下载途中切歌 → 旧曲下载完成后**不得**把状态改回 PLAYING/写过期快照
 *      （still_current 护栏；旧代码在切歌后 ~下载完成点 会把 BUFFER 覆盖成 PLAYING）；
 *   P5 错误后 play(cur) 重试 → 状态重新走 BUFFER→PLAYING，err 清零。
 *
 * 编译（宿主，ncm_app 目录下）：
 *   gcc -O2 -ffunction-sections -DJSMN_HEADER -I. -I../sdk -I../meow_launcherd \
 *       -Icore -Ivendor/jsmn -c bench/player_flow_sim.c -o /tmp/pf.o
 *   gcc -O2 -ffunction-sections -DJSMN_HEADER -I. -I../sdk -I../meow_launcherd \
 *       -Icore -Ivendor/jsmn -Ivendor/minimp3 -Ivendor/dr_flac -c app/play/player_manager.c -o /tmp/pf_pm.o
 *   gcc -O2 -Wl,--gc-sections -o player_flow_sim /tmp/pf.o /tmp/pf_pm.o -lpthread -lm
 * 运行：./player_flow_sim  （0 网络；PASS/FAIL 退出码）
 * §19：P6 覆盖缓存键=歌曲ID+档位 + flac type → .flac 落盘扩展名。
 */
#include "../app/ncm_app_internal.h"
#include "../app/play/decoder.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdarg.h>
#include <unistd.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 = 1;
int             g_host_mock = 0;

/* ---- 公共 stub ---- */
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;
}
void meow_log(meow_log_level lvl, const char *fmt, ...) { (void)lvl; (void)fmt; }
void meow_audio_on_preempt(meow_audio_preempt_fn cb, void *ctx) { (void)cb; (void)ctx; }

/* ---- appstate stub：窗内全命中，id=1000+idx ---- */
int appstate_song_copy(int gidx, ncm_song_t *out)
{
    if (gidx < 0 || gidx >= g_st.track_ids_count) return -1;
    memset(out, 0, sizeof *out);
    snprintf(out->id, sizeof out->id, "%d", 1000 + gidx);
    snprintf(out->name, sizeof out->name, "Song%d", gidx);
    out->duration_ms = 180000;
    return 0;
}
int appstate_song_fetch(int gidx, ncm_song_t *out) { return appstate_song_copy(gidx, out) == 0 ? NCM_OK : NCM_ERR_ARG; }

/* ---- 缓存/网络 stub ----
 * g_cache_ok=1 → lookup 命中（给真实存在的 /tmp 文件，免下载）；
 * 否则走下载：song_url(g_url_rc 可注入失败) → http_download(g_dl_delay_ms 模拟慢) → commit。 */
static int g_cache_ok = 1;
static int g_url_rc = NCM_OK;
static int g_dl_delay_ms = 0;
static int g_downloads;         /* http_download 调用数（song_url 请求放大检测） */
static const char *g_url_type = "mp3";   /* §19：song_url 注入的 type（mp3/flac） */
static char g_last_key[80];     /* ncm_cache_open 收到的键（档位键断言用） */
static char g_last_ext[8];      /* ncm_cache_open 收到的扩展名 */

int ncm_cache_lookup(const ncm_cache_t *c, const char *id, const char *ext, char *out, size_t out_sz)
{
    (void)c; (void)id; (void)ext;
    if (!g_cache_ok) return NCM_ERR_NOENT;
    snprintf(out, out_sz, "/tmp/pf_sim.mp3");
    return NCM_OK;
}
int ncm_cache_open(const ncm_cache_t *c, const char *id, const char *ext, ncm_cache_writer_t **w)
{
    (void)c;
    snprintf(g_last_key, sizeof g_last_key, "%s", id);
    snprintf(g_last_ext, sizeof g_last_ext, "%s", ext ? ext : "");
    *w = (ncm_cache_writer_t *)calloc(1, 64); return NCM_OK;
}
int ncm_cache_write(ncm_cache_writer_t *w, const unsigned char *d, size_t l) { (void)w; (void)d; (void)l; return NCM_OK; }
int ncm_cache_commit(ncm_cache_writer_t *w) { free(w); g_cache_ok = 1; return NCM_OK; }
int ncm_cache_abort(ncm_cache_writer_t *w) { free(w); return NCM_OK; }
int ncm_cache_evict(const ncm_cache_t *c) { (void)c; return NCM_OK; }
void ncm_cache_set_limit_gb(ncm_cache_t *c, int gb) { (void)c; (void)gb; }

int ncm_api_song_url_auto(const char *dev, const char *ck, const char *id, int level, ncm_play_url_t *out)
{
    (void)dev; (void)ck; (void)id; (void)level;
    if (g_url_rc != NCM_OK) return g_url_rc;
    memset(out, 0, sizeof *out);
    snprintf(out->url, sizeof out->url, "http://stub/%s.%s", id, g_url_type);
    snprintf(out->type, sizeof out->type, "%s", g_url_type);
    out->size = 4 * 1024 * 1024;
    return NCM_OK;
}

int ncm_http_download(const ncm_http_req_t *req, ncm_http_write_cb cb, void *ctx,
                      size_t maxb, ncm_http_resp_t *resp)
{
    (void)req; (void)maxb;
    g_downloads++;
    if (g_dl_delay_ms > 0) usleep((useconds_t)g_dl_delay_ms * 1000);
    unsigned char chunk[65536];
    memset(chunk, 0x5A, sizeof chunk);
    for (int i = 0; i < 8; i++)                    /* 512KB 总分发（进度回调会走 8 次） */
        if (cb(ctx, chunk, sizeof chunk) != 0) break;
    memset(resp, 0, sizeof *resp);
    resp->status = 200;
    return NCM_OK;
}

/* ---- 解码器 stub（§19：player_manager 改走 ncm_dec_* 分发层）：
 * g_eof 前恒有数据（P1 用 g_reads_left 控制播完点） ---- */
static int g_eof;
static int g_reads_left = -1;    /* >=0: 剩余读次数后 EOF；-1: 直到 g_eof */
static int g_dec_open_bits = 16; /* 模拟流位宽（记录用） */

int ncm_dec_open(ncm_decoder_t **out, const char *path, int *rate, int *ch, int *bits,
                 int64_t *total_frames)
{
    (void)path;
    *out = (ncm_decoder_t *)calloc(1, 16);
    if (rate) *rate = 44100;
    if (ch) *ch = 2;
    if (bits) *bits = g_dec_open_bits;
    if (total_frames) *total_frames = 44100 * 180;
    return *out ? 0 : -1;
}
int64_t ncm_dec_read(ncm_decoder_t *d, void *buf, int64_t cap_frames)
{
    (void)d;
    if (g_eof) return 0;
    if (g_reads_left == 0) return 0;
    if (g_reads_left > 0) g_reads_left--;
    memset(buf, 0, (size_t)cap_frames * 2 * sizeof(int16_t));
    return cap_frames;
}
int  ncm_dec_seek_ms(ncm_decoder_t *d, int64_t ms, int64_t fb, int64_t dur)
{ (void)d; (void)ms; (void)fb; (void)dur; return 0; }
void ncm_dec_close(ncm_decoder_t *d) { free(d); }
const char *ncm_dec_format(const ncm_decoder_t *d) { (void)d; return "stub"; }

/* §19：song_local_file 的缓存键用 ncm_api_level_str(g_level)；ext 判定用 ncm_streq */
int ncm_streq(const char *a, const char *b)
{
    if (!a || !b) return 0;
    return strcmp(a, b) == 0;
}
const char *ncm_api_level_str(int level)
{
    switch (level) {
    case NCM_LEVEL_HIRES:    return "hires";
    case NCM_LEVEL_LOSSLESS: return "lossless";
    case NCM_LEVEL_EXHIGH:   return "exhigh";
    case NCM_LEVEL_HIGHER:   return "higher";
    default:                 return "standard";
    }
}

/* ---- 音频输出 stub：g_write_fail 注入写失败 ---- */
static int g_write_fail;
static int g_writes;
static int g_opens;             /* audio_out_open 次数（每首 run_song 开一次） */

int  audio_out_open(int rate, int ch, int bits) { (void)rate; (void)ch; (void)bits; g_opens++; return 0; }
int  audio_out_write(const void *s, int frames)
{ (void)s; g_writes++; return g_write_fail ? -1 : frames; }
int  audio_out_pause(int paused) { (void)paused; return 0; }
void audio_out_close(void) { }
int  audio_out_buffered_ms(void) { return 0; }
void audio_out_set_target(int ms) { (void)ms; }

/* ---- 歌词（未被调用的 worker 会被 gc-sections 丢弃；lyric_clear 由 worker 用，防御性提供） ---- */
void lyric_clear(void) { }
int  lyric_parse(const char *a, const char *b) { (void)a; (void)b; return 0; }

static int g_fail;
#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)

static int state(void) { return player_manager_state(); }

static int wait_state(int want, int ms)
{
    for (int t = 0; t < ms; t += 10) { if (state() == want) return 1; usleep(10 * 1000); }
    return 0;
}

static int wait_err(int want, int ms)   /* 等错误码出现（初始态可能已是 STOPPED，等状态有竞态） */
{
    for (int t = 0; t < ms; t += 10) { if (player_manager_error() == want) return 1; usleep(10 * 1000); }
    return 0;
}

static int wait_downloads(int want, int ms)
{
    for (int t = 0; t < ms; t += 10) { if (g_downloads >= want) return 1; usleep(10 * 1000); }
    return 0;
}

int main(void)
{
    /* 假 mp3 文件（cache 命中路径 stat 用） */
    FILE *f = fopen("/tmp/pf_sim.mp3", "wb");
    if (!f) { printf("FAIL  tmp file\n"); return 1; }
    for (int i = 0; i < 4096; i++) fputc(i & 0xFF, f);
    fclose(f);

    memset(&g_st, 0, sizeof g_st);
    g_st.track_ids_count = 3;
    for (int i = 0; i < 3; i++) g_st.song_ids[i] = 1000 + i;
    g_st.level = NCM_LEVEL_STANDARD;
    g_st.cache_limit_gb = 10;

    if (player_manager_start() != 0) { printf("FAIL  start\n"); return 1; }

    printf("== P1: natural finish -> auto-advance, err=0 ==\n");
    g_cache_ok = 1; g_reads_left = -1; g_eof = 0; g_write_fail = 0;
    player_manager_play(0);
    CHECK(wait_state(NCM_PC_PLAYING, 2000), "song0 playing (持续读流态可捕获)");
    /* stub 解码/写瞬时完成，整列顺排在一次 poll 内跑完（cur 直接冲到 -1）——
     * 改用 audio_out_open 计数判定：3 首全开过 = 自然顺延链走通。 */
    g_reads_left = 1;                      /* song0 再读 1 次即 EOF → 自然播完 */
    for (int t = 0; t < 4000 && state() != NCM_PC_STOPPED; t += 20) {
        if (g_reads_left <= 0) g_reads_left = 1;
        usleep(20 * 1000);
    }
    CHECK(g_opens == 3, "auto-advance chain: audio opens=%d (expect 3 首全开)", g_opens);
    CHECK(state() == NCM_PC_STOPPED && player_manager_error() == 0,
          "end of playlist -> STOPPED err=%d (expect 0)", player_manager_error());

    printf("== P2: write fail (stream dead) -> STOPPED + err, cur unchanged (不连环跳歌) ==\n");
    g_reads_left = -1; g_eof = 0; g_write_fail = 1; g_writes = 0;
    player_manager_play(1);
    CHECK(wait_err(NCM_ERR_IO, 2000), "err=NCM_ERR_IO after write fail (rc=%d)", player_manager_error());
    CHECK(wait_state(NCM_PC_STOPPED, 1000), "stopped after write fail");
    usleep(500 * 1000);
    CHECK(player_manager_playing_song() == 1, "cur=%d (expect 1, 未跳歌)", player_manager_playing_song());
    CHECK(state() == NCM_PC_STOPPED, "stays STOPPED (no cascade)");
    CHECK(g_writes <= 2, "writes=%d (≤2: 第一次失败即停，不连环)", g_writes);
    g_write_fail = 0;

    printf("== P3: no stream url -> STOPPED + NOTFOUND + errmsg ==\n");
    g_url_rc = NCM_ERR_NOTFOUND; g_cache_ok = 0;
    player_manager_play(2);
    CHECK(wait_err(NCM_ERR_NOTFOUND, 2000), "err=NOTFOUND on no-stream (rc=%d)", player_manager_error());
    CHECK(wait_state(NCM_PC_STOPPED, 1000), "stopped on no-stream");
    pthread_mutex_lock(&g_play.mu);
    const char *em = g_play.errmsg;
    int has_msg = em[0] != 0;
    pthread_mutex_unlock(&g_play.mu);
    CHECK(has_msg, "errmsg set (UI 可显示)");
    g_url_rc = NCM_OK;

    printf("== P4: switch during slow download -> no stale PLAYING overwrite ==\n");
    g_cache_ok = 0; g_dl_delay_ms = 250; g_eof = 0; g_reads_left = -1;
    player_manager_play(0);
    CHECK(wait_downloads(1, 3000), "song0 download started");
    player_manager_play(1);                /* 旧曲下载途中切歌 */
    /* 旧曲下载 +250ms 完成；新代码 still_current 护栏直接返回（状态保持 BUFFER），
     * 旧代码会在此点把 state 覆盖成 PLAYING。+280ms 落在新曲下载窗口内（~+300 才开始）。 */
    usleep(280 * 1000);
    CHECK(state() == NCM_PC_BUFFER,
          "after switch+during new download state=%d (expect BUFFER=%d; 旧代码被旧曲改成 PLAYING)",
          state(), NCM_PC_BUFFER);
    CHECK(wait_state(NCM_PC_PLAYING, 3000), "new song eventually playing");
    ncm_song_t snap;
    CHECK(player_manager_current_song(&snap) == 0 && strcmp(snap.id, "1001") == 0,
          "snapshot id=%s (expect 1001, 无过期快照)", snap.id);
    g_eof = 1;                             /* 让新曲自然收尾 */
    usleep(200 * 1000);
    g_dl_delay_ms = 0;

    printf("== P5: retry after error -> BUFFER->PLAYING, err cleared ==\n");
    g_eof = 0; g_reads_left = -1; g_url_rc = NCM_ERR_NOTFOUND;
    g_cache_ok = 0;
    player_manager_play(2);                /* 制造错误 */
    CHECK(wait_err(NCM_ERR_NOTFOUND, 2000), "error state ready (rc=%d)", player_manager_error());
    g_url_rc = NCM_OK;                     /* 网络恢复 */
    player_manager_play(player_manager_playing_song());   /* 重试（UI 播放键路径） */
    CHECK(wait_state(NCM_PC_PLAYING, 3000), "retry playing");
    CHECK(player_manager_error() == 0, "err cleared on retry");
    g_eof = 1;

    printf("== P6: cache key = id+level, flac type -> .flac ext (§19) ==\n");
    usleep(300 * 1000);                    /* 等 P5 曲收尾 */
    g_eof = 0; g_reads_left = -1; g_cache_ok = 0; g_dl_delay_ms = 0;
    g_url_type = "flac";
    player_manager_set_quality(NCM_LEVEL_LOSSLESS, 10);   /* 换档 → g_level=lossless */
    player_manager_play(0);
    CHECK(wait_state(NCM_PC_PLAYING, 3000), "flac download song playing");
    CHECK(strcmp(g_last_key, "1000_lossless") == 0,
          "cache key=%s (expect 1000_lossless = id+档位)", g_last_key);
    CHECK(strcmp(g_last_ext, "flac") == 0,
          "cache ext=%s (expect flac, type=flac → .flac 落盘)", g_last_ext);
    g_url_type = "mp3";
    player_manager_set_quality(NCM_LEVEL_STANDARD, 10);   /* 还原，避免影响后续（无） */
    g_eof = 1;

    usleep(200 * 1000);
    player_manager_stop_thread();
    printf(g_fail ? "== PLAYER FLOW SIM: FAIL ==\n" : "== PLAYER FLOW SIM: ALL PASS ==\n");
    return g_fail;
}