/* test/font_resolve_bench.c — M31 字体路径记忆化耗时对比（宿主，不依赖设备）。
 *
 * 同一棵树两种口径：
 *   walk = 每次都重扫（= 加缓存前的 resolve_font 行为），由 font_cache_invalidate() 强制；
 *   hit  = 缓存命中 + access() 校验（= 加缓存后开书路径）。
 * 用法：./font_resolve_bench_host [目录] [迭代数]，不传目录则先造一棵 35 目录的树。
 */
#include "font_resolve.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <time.h>
#include <unistd.h>

static void mkdirs(const char *path)
{
    char t[512];
    snprintf(t, sizeof t, "%s", path);
    for (char *p = t + 1; *p; p++) {
        if (*p == '/') { *p = 0; mkdir(t, 0755); *p = '/'; }
    }
    mkdir(t, 0755);
}

static void write_file(const char *path, const char *body)
{
    FILE *f = fopen(path, "wb");
    if (!f) return;
    fputs(body, f);
    fclose(f);
}

static void make_fonts_tree(const char *root, int ndirs, int files_per_dir)
{
    char p[512];
    for (int i = 0; i < ndirs; i++) {
        snprintf(p, sizeof p, "%s/family_%02d/sub", root, i);
        mkdirs(p);
        for (int j = 0; j < files_per_dir; j++) {
            snprintf(p, sizeof p, "%s/family_%02d/readme_%d.txt", root, i, j);
            write_file(p, "x");
        }
        snprintf(p, sizeof p, "%s/family_%02d/sub/Font%02d.ttf", root, i, i);
        write_file(p, "x");
    }
}

static double ms_now(void)
{
    struct timespec ts;
    clock_gettime(CLOCK_MONOTONIC, &ts);
    return (double)ts.tv_sec * 1000.0 + (double)ts.tv_nsec / 1e6;
}

typedef struct stat_res { double min, avg, max; } stat_res;

static stat_res run(const char *root, int iters, int invalidate_each)
{
    stat_res r = { 1e9, 0, 0 };
    double sum = 0;
    for (int i = 0; i < iters; i++) {
        if (invalidate_each) font_cache_invalidate();
        double t0 = ms_now();
        (void)font_resolve(root);
        double dt = ms_now() - t0;
        if (dt < r.min) r.min = dt;
        if (dt > r.max) r.max = dt;
        sum += dt;
    }
    r.avg = iters ? sum / (double)iters : 0;
    return r;
}

int main(int argc, char **argv)
{
    const char *root = (argc > 1) ? argv[1] : NULL;
    int iters = (argc > 2) ? atoi(argv[2]) : 200;
    char tmpbuf[512] = { 0 };

    if (!root) {
        const char *base = getenv("TMPDIR");
        if (!base || !base[0]) base = "/tmp";
        snprintf(tmpbuf, sizeof tmpbuf, "%s/fontbench_XXXXXX", base);
        if (!mkdtemp(tmpbuf)) { printf("mkdtemp 失败\n"); return 2; }
        make_fonts_tree(tmpbuf, 35, 3);
        root = tmpbuf;
    }
    /* 预热（首轮含 dentry 冷缓存，不计入） */
    font_cache_invalidate(); font_resolve(root);
    font_resolve(root);

    const char *p = font_resolve(root);
    printf("root=%s\n", root);
    printf("font=%s\n", p ? p : "(none)");
    stat_res w = run(root, iters, 1);   /* 每次失效 = 旧行为：每次开书重 walk */
    stat_res h = run(root, iters, 0);   /* 缓存命中 + access 校验 = 新行为 */
    printf("walk (每次重扫): min=%.3f avg=%.3f max=%.3f ms\n", w.min, w.avg, w.max);
    printf("hit  (缓存+access): min=%.3f avg=%.3f max=%.3f ms\n", h.min, h.avg, h.max);
    if (h.avg > 0) printf("提速: %.1fx\n", w.avg / h.avg);

    if (tmpbuf[0]) {
        char cmd[600];
        snprintf(cmd, sizeof cmd, "rm -rf '%s'", tmpbuf);
        if (system(cmd) != 0) { /* 忽略 */ }
    }
    return 0;
}