/* test_reader_core.c — 阅读器纯逻辑宿主测试（无 SDK/硬件）。
 *
 * 覆盖：
 *   R1 页源契约：空册 / 不可读目录 / 越界 open / 重复 open-close / 首末页 / 自然序 /
 *      隐藏文件与子目录排除 / 销毁后失效；
 *   R2 契约对两种消费方式通用：meta() 给条漫连续滚动排高度，open() 给左右翻页取图；
 *   R3 图片头探测：PNG/JPEG/BMP 原始尺寸（不解码）；
 *   R4 方向语义：tap 分区 / 拖动增量（RTL 默认与 LTR）/ clamp / 提交阈值；
 *   R5 fit 三档 / 缩放 / 平移夹取 / 进场方向 / 档位循环；
 *   R6 阅读方向状态（M3 API）。
 *
 * 编译（在 tuku/ 下）：
 *   gcc -Wall -Wextra -O1 -I. test/test_reader_core.c logic/library.c logic/reader.c \
 *       logic/reader/page_source.c logic/reader/nav.c -o test/test_reader_core
 * 或直接 test/run_tests.sh。
 */
#include "logic/library.h"
#include "logic/reader.h"
#include "logic/reader/nav.h"
#include "logic/reader/page_source.h"

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

static int g_pass, g_fail;
#define CHECK(cond, ...) do { \
    if (cond) { g_pass++; } \
    else { g_fail++; printf("FAIL %s:%d  ", __FILE__, __LINE__); printf(__VA_ARGS__); printf("\n"); } \
} while (0)

/* ============================================================ */
/* 假解码器：meow_img* 用堆上假句柄代替，记录 open/close 次数     */
/* ============================================================ */
typedef struct fake_img { int id; } fake_img;

static int g_loads, g_frees;
static int g_last_maxdim;
static char g_last_path[MR_PATH_MAX];

static meow_img *fake_load(const char *path, void *ud, int maxdim)
{
    (void)ud;
    g_loads++;
    g_last_maxdim = maxdim;
    snprintf(g_last_path, sizeof g_last_path, "%s", path ? path : "");
    fake_img *f = (fake_img *)malloc(sizeof *f);
    if (!f) return NULL;
    f->id = g_loads;
    return (meow_img *)f;
}

static void fake_unload(meow_img *img)
{
    g_frees++;
    free(img);
}

/* ============================================================ */
/* 临时目录工具                                                  */
/* ============================================================ */
static int mkdir_p(const char *path)
{
    char tmp[MR_PATH_MAX];
    snprintf(tmp, sizeof tmp, "%s", path);
    for (size_t i = 1; i <= strlen(tmp); i++) {
        if (tmp[i] == '/' || tmp[i] == '\0') {
            char ch = tmp[i];
            tmp[i] = '\0';
            if (mkdir(tmp, 0755) != 0) {
                struct stat st;
                if (stat(tmp, &st) != 0 || !S_ISDIR(st.st_mode)) return -1;
            }
            tmp[i] = ch;
        }
    }
    return 0;
}

static int write_bytes(const char *path, const unsigned char *buf, int len)
{
    FILE *f = fopen(path, "wb");
    if (!f) return -1;
    int ok = fwrite(buf, 1, (size_t)len, f) == (size_t)len;
    if (fclose(f) != 0) ok = 0;
    return ok ? 0 : -1;
}

static int touch_file(const char *path)
{
    return write_bytes(path, (const unsigned char *)"x", 1);
}

static int rm_rf(const char *path)
{
    struct stat st;
    if (lstat(path, &st) != 0) return -1;
    if (!S_ISDIR(st.st_mode)) return unlink(path);
    DIR *d = opendir(path);
    if (!d) return -1;
    struct dirent *de;
    while ((de = readdir(d)) != NULL) {
        if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0) continue;
        char full[MR_PATH_MAX];
        snprintf(full, sizeof full, "%s/%s", path, de->d_name);
        rm_rf(full);
    }
    closedir(d);
    return rmdir(path);
}

/* ---- 头文件样例（只写头，不写像素） ---- */
static int write_png(const char *path, int w, int h)
{
    unsigned char b[24] = {
        0x89, 'P', 'N', 'G', 0x0D, 0x0A, 0x1A, 0x0A,
        0, 0, 0, 13, 'I', 'H', 'D', 'R',
        (unsigned char)(w >> 24), (unsigned char)(w >> 16),
        (unsigned char)(w >> 8), (unsigned char)w,
        (unsigned char)(h >> 24), (unsigned char)(h >> 16),
        (unsigned char)(h >> 8), (unsigned char)h,
    };
    return write_bytes(path, b, (int)sizeof b);
}

static int write_jpeg(const char *path, int w, int h)
{
    unsigned char b[16] = {
        0xFF, 0xD8,                          /* SOI */
        0xFF, 0xC0, 0x00, 0x11,              /* SOF0, len=17 */
        0x08,                                /* precision */
        (unsigned char)(h >> 8), (unsigned char)h,
        (unsigned char)(w >> 8), (unsigned char)w,
        0x03, 0x01, 0x11, 0x00,              /* 3 分量（长度不足也无妨：只读到 w/h） */
    };
    return write_bytes(path, b, (int)sizeof b);
}

static int write_bmp(const char *path, int w, int h)
{
    unsigned char b[26] = { 0 };
    b[0] = 'B';
    b[1] = 'M';
    b[18] = (unsigned char)w; b[19] = (unsigned char)(w >> 8);
    b[20] = (unsigned char)(w >> 16); b[21] = (unsigned char)(w >> 24);
    b[22] = (unsigned char)h; b[23] = (unsigned char)(h >> 8);
    b[24] = (unsigned char)(h >> 16); b[25] = (unsigned char)(h >> 24);
    return write_bytes(path, b, (int)sizeof b);
}

/* ============================================================ */
/* R1/R2 页源契约                                                */
/* ============================================================ */
static void test_contract(void)
{
    char tmpl[] = "./mr_reader_XXXXXX";
    char *root = mkdtemp(tmpl);
    CHECK(root != NULL, "mkdtemp");
    if (!root) return;

    char p[MR_PATH_MAX];
    snprintf(p, sizeof p, "%s/page10.png", root); write_png(p, 600, 900);
    snprintf(p, sizeof p, "%s/page2.jpg", root);  write_jpeg(p, 1200, 1800);
    snprintf(p, sizeof p, "%s/page1.bmp", root);  write_bmp(p, 800, 1200);
    snprintf(p, sizeof p, "%s/notes.txt", root);  touch_file(p);
    snprintf(p, sizeof p, "%s/.hidden.png", root); touch_file(p);
    snprintf(p, sizeof p, "%s/sub.png", root);    mkdir_p(p);          /* 目录不参与成册 */
    snprintf(p, sizeof p, "%s/sub/inside.png", root); touch_file(p);

    mr_dir_book db;
    mr_book book;
    int n = mr_dir_book_init(&db, root, 640, fake_load, fake_unload, NULL);
    CHECK(n == 3, "init count=%d (want 3)", n);
    CHECK(db.count == 3, "db.count=%d", db.count);
    mr_dir_book_bind(&book, &db);

    CHECK(mr_book_valid(&book) == 1, "book valid");
    CHECK(mr_book_count(&book) == 3, "book count=3");
    CHECK(mr_book_count(NULL) == 0, "NULL count safe");
    CHECK(mr_book_valid(NULL) == 0, "NULL invalid");
    CHECK(mr_book_open(NULL, 0) == NULL, "NULL open safe");
    mr_book_close(NULL, NULL);                  /* 全程 NULL 安全，不崩 */
    mr_book_destroy(NULL);

    /* 自然序 + 首末页 */
    char path[MR_PATH_MAX];
    mr_dir_book_path(&db, 0, path, sizeof path);
    CHECK(strstr(path, "page1.bmp") != NULL, "page 0 = page1 got %s", path);
    mr_dir_book_path(&db, 1, path, sizeof path);
    CHECK(strstr(path, "page2.jpg") != NULL, "page 1 = page2 got %s", path);
    mr_dir_book_path(&db, 2, path, sizeof path);
    CHECK(strstr(path, "page10.png") != NULL, "page 2 = page10 got %s", path);

    /* 越界：open/meta/path 全部安全 */
    CHECK(mr_book_open(&book, -1) == NULL, "open(-1) NULL");
    CHECK(mr_book_open(&book, 3) == NULL, "open(count) NULL");
    CHECK(mr_book_open(&book, 9999) == NULL, "open(9999) NULL");
    int mw = -1, mh = -1;
    CHECK(mr_book_meta(&book, -1, &mw, &mh) == 0 && mw == 0 && mh == 0, "meta(-1) unknown");
    CHECK(mr_book_meta(&book, 3, &mw, &mh) == 0, "meta(count) unknown");
    mr_dir_book_path(&db, 9, path, sizeof path);
    CHECK(path[0] == '\0', "path out of range empty");

    /* 首末页 open + 重复 open-close（每次 open 的句柄独立，各 close 一次） */
    int loads0 = g_loads, frees0 = g_frees;
    meow_img *a = mr_book_open(&book, 0);
    CHECK(a != NULL, "open(0) ok");
    CHECK(strstr(g_last_path, "page1.bmp") != NULL, "open(0) path %s", g_last_path);
    CHECK(g_last_maxdim == 640, "open passes maxdim=%d", g_last_maxdim);
    meow_img *a2 = mr_book_open(&book, 0);
    CHECK(a2 != NULL && a2 != a, "re-open(0) gives independent handle");
    CHECK(g_loads == loads0 + 2, "two loads");
    mr_book_close(&book, a);
    mr_book_close(&book, a2);
    CHECK(g_frees == frees0 + 2, "frees=%d", g_frees - frees0);

    /* 再开再关一轮：契约允许同一页反复 open/close */
    a = mr_book_open(&book, 0);
    CHECK(a != NULL && g_loads == loads0 + 3, "re-open after close");
    mr_book_close(&book, a);
    CHECK(g_frees == frees0 + 3, "re-close frees");

    meow_img *last = mr_book_open(&book, 2);
    CHECK(last != NULL, "open(last) ok");
    CHECK(strstr(g_last_path, "page10.png") != NULL, "open(last) path %s", g_last_path);
    mr_book_close(&book, last);

    /* meta：PNG/JPEG/BMP 头解析 */
    CHECK(mr_book_meta(&book, 0, &mw, &mh) == 1 && mw == 800 && mh == 1200,
          "meta bmp=%dx%d", mw, mh);
    CHECK(mr_book_meta(&book, 1, &mw, &mh) == 1 && mw == 1200 && mh == 1800,
          "meta jpeg=%dx%d", mw, mh);
    CHECK(mr_book_meta(&book, 2, &mw, &mh) == 1 && mw == 600 && mh == 900,
          "meta png=%dx%d", mw, mh);

    /* R2：契约对条漫通用——用 meta 累加高度，按滚动位置定位页（M7 可直接复用）。 */
    long y = 0, heights[3];
    for (int i = 0; i < 3; i++) {
        int sw = 0, sh = 0;
        mr_book_meta(&book, i, &sw, &sh);
        int fw = 0, fh = 0;
        mr_nav_fit_size(MR_FIT_WIDTH, sw, sh, 480, 720, &fw, &fh);
        heights[i] = fh;
        y += fh;
    }
    CHECK(y == 720 + 720 + 720, "column height=%ld", y);
    CHECK(heights[0] == 720 && heights[1] == 720, "meta-derived fit heights");

    /* 销毁：provider 失效，二次 destroy 幂等 */
    mr_book_destroy(&book);
    CHECK(mr_book_valid(&book) == 0, "destroyed invalid");
    CHECK(mr_book_open(&book, 0) == NULL, "open after destroy NULL");
    mr_book_destroy(&book);
    mr_dir_book_free(&db);

    rm_rf(root);
}

static void test_empty_and_bad(void)
{
    char tmpl[] = "./mr_reader_empty_XXXXXX";
    char *root = mkdtemp(tmpl);
    CHECK(root != NULL, "mkdtemp empty");

    /* 空目录：可读但 0 页（≠ 错误） */
    mr_dir_book db;
    int n = mr_dir_book_init(&db, root, 720, fake_load, fake_unload, NULL);
    CHECK(n == 0, "empty dir count=0 got %d", n);
    CHECK(db.count == 0, "empty db count");
    mr_book book;
    mr_dir_book_bind(&book, &db);
    CHECK(mr_book_count(&book) == 0, "empty book count 0");
    CHECK(mr_book_open(&book, 0) == NULL, "empty open NULL");
    CHECK(mr_book_meta(&book, 0, NULL, NULL) == 0, "empty meta NULL-safe");
    mr_dir_book_free(&db);

    /* 目录不存在：-1，且 db 可安全 free */
    mr_dir_book bad;
    CHECK(mr_dir_book_init(&bad, "/no/such/dir/tuku-reader", 720, fake_load, fake_unload,
                           NULL) == -1, "missing dir -> -1");
    CHECK(bad.count == 0 && bad.names == NULL, "missing dir cleared");
    mr_dir_book_free(&bad);

    /* 参数非法 */
    CHECK(mr_dir_book_init(NULL, root, 720, fake_load, fake_unload, NULL) == -1, "NULL db");
    CHECK(mr_dir_book_init(&bad, root, 720, NULL, fake_unload, NULL) == -1, "NULL load");
    CHECK(mr_dir_book_init(&bad, root, 720, fake_load, NULL, NULL) == -1, "NULL unload");
    CHECK(mr_dir_book_init(&bad, "", 720, fake_load, fake_unload, NULL) == -1, "empty dirname");

    rm_rf(root);
}

/* ============================================================ */
/* R4 方向语义                                                   */
/* ============================================================ */
static void test_direction_nav(void)
{
    const int W = 480;
    CHECK(mr_nav_tap_zone(0, W) == MR_ZONE_LEFT, "zone 0");
    CHECK(mr_nav_tap_zone(159, W) == MR_ZONE_LEFT, "zone 159");
    CHECK(mr_nav_tap_zone(160, W) == MR_ZONE_MIDDLE, "zone 160");
    CHECK(mr_nav_tap_zone(319, W) == MR_ZONE_MIDDLE, "zone 319");
    CHECK(mr_nav_tap_zone(320, W) == MR_ZONE_RIGHT, "zone 320");
    CHECK(mr_nav_tap_zone(479, W) == MR_ZONE_RIGHT, "zone 479");
    CHECK(mr_nav_tap_zone(10, 0) == MR_ZONE_MIDDLE, "zone bad width");

    /* RTL（默认）：屏左=下一页，屏右=上一页 */
    CHECK(mr_nav_tap_delta(1, MR_ZONE_LEFT) == 1, "RTL left=next");
    CHECK(mr_nav_tap_delta(1, MR_ZONE_RIGHT) == -1, "RTL right=prev");
    CHECK(mr_nav_tap_delta(1, MR_ZONE_MIDDLE) == 0, "RTL middle=chrome");
    /* LTR：屏左=上一页，屏右=下一页 */
    CHECK(mr_nav_tap_delta(0, MR_ZONE_LEFT) == -1, "LTR left=prev");
    CHECK(mr_nav_tap_delta(0, MR_ZONE_RIGHT) == 1, "LTR right=next");
    CHECK(mr_nav_tap_delta(0, MR_ZONE_MIDDLE) == 0, "LTR middle=chrome");

    /* 拖动：向右（dx>0）露出左侧那页 */
    CHECK(mr_nav_swipe_delta(1, 120) == 1, "RTL drag right=next");
    CHECK(mr_nav_swipe_delta(1, -120) == -1, "RTL drag left=prev");
    CHECK(mr_nav_swipe_delta(0, 120) == -1, "LTR drag right=prev");
    CHECK(mr_nav_swipe_delta(0, -120) == 1, "LTR drag left=next");
    CHECK(mr_nav_swipe_delta(1, 0) == 0, "drag 0 no-op");

    CHECK(mr_nav_clamp_page(-5, 10) == 0, "clamp low");
    CHECK(mr_nav_clamp_page(20, 10) == 9, "clamp high");
    CHECK(mr_nav_clamp_page(3, 10) == 3, "clamp inside");
    CHECK(mr_nav_clamp_page(0, 0) == -1, "clamp empty");

    CHECK(mr_nav_commit_dist(480) == 120, "commit dist 480 -> 120");
    CHECK(mr_nav_commit_dist(200) == 60, "commit dist 200 -> 60");
    CHECK(mr_nav_commit_dist(2000) == 160, "commit dist 2000 -> 160");
    CHECK(mr_nav_commit(119, 480) == 0, "119 not committed");
    CHECK(mr_nav_commit(120, 480) == 1, "120 committed");
    CHECK(mr_nav_commit(-120, 480) == 1, "-120 committed");

    /* 进场方向：RTL 下一页从左侧进，LTR 下一页从右侧进 */
    CHECK(mr_nav_slide_from(1, 1, W) == -W, "RTL next enters left");
    CHECK(mr_nav_slide_from(1, -1, W) == W, "RTL prev enters right");
    CHECK(mr_nav_slide_from(0, 1, W) == W, "LTR next enters right");
    CHECK(mr_nav_slide_from(0, -1, W) == -W, "LTR prev enters left");
    CHECK(mr_nav_slide_from(1, 0, W) == 0, "slide 0");
}

/* ============================================================ */
/* R5 fit / 缩放 / 平移                                          */
/* ============================================================ */
static void test_fit_zoom_pan(void)
{
    int w = 0, h = 0;
    /* 竖图 1000×1500，视口 480×720 */
    CHECK(mr_nav_fit_size(MR_FIT_WIDTH, 1000, 1500, 480, 720, &w, &h) == 0 &&
          w == 480 && h == 720, "fit width %dx%d", w, h);
    CHECK(mr_nav_fit_size(MR_FIT_HEIGHT, 1000, 1500, 480, 720, &w, &h) == 0 &&
          w == 480 && h == 720, "fit height %dx%d", w, h);
    CHECK(mr_nav_fit_size(MR_FIT_ORIGINAL, 1000, 1500, 480, 720, &w, &h) == 0 &&
          w == 1000 && h == 1500, "fit original %dx%d", w, h);

    /* 横图 1500×1000：适宽缩到 480×320，适高放大到 1080×720（可左右平移） */
    CHECK(mr_nav_fit_size(MR_FIT_WIDTH, 1500, 1000, 480, 720, &w, &h) == 0 &&
          w == 480 && h == 320, "landscape fit width %dx%d", w, h);
    CHECK(mr_nav_fit_size(MR_FIT_HEIGHT, 1500, 1000, 480, 720, &w, &h) == 0 &&
          w == 1080 && h == 720, "landscape fit height %dx%d", w, h);

    CHECK(mr_nav_fit_size(MR_FIT_WIDTH, 0, 100, 480, 720, &w, &h) == -1, "fit bad src");
    CHECK(mr_nav_fit_size(MR_FIT_WIDTH, 100, 100, 0, 720, &w, &h) == -1, "fit bad viewport");
    CHECK(mr_nav_fit_size(MR_FIT_WIDTH, 100, 100, 480, 720, NULL, &h) == -1, "fit NULL out");

    CHECK(mr_nav_zoom_size(480, 720, 200, &w, &h) == 0 && w == 960 && h == 1440,
          "zoom 200 %dx%d", w, h);
    CHECK(mr_nav_zoom_size(480, 720, 150, &w, &h) == 0 && w == 720 && h == 1080,
          "zoom 150 %dx%d", w, h);
    CHECK(mr_nav_zoom_size(0, 720, 200, &w, &h) == -1, "zoom bad size");

    int lx = -1, ly = -1;
    mr_nav_pan_limit(960, 1440, 480, 720, &lx, &ly);
    CHECK(lx == 240 && ly == 360, "pan limit %d,%d", lx, ly);
    mr_nav_pan_limit(480, 720, 480, 720, &lx, &ly);
    CHECK(lx == 0 && ly == 0, "no overflow no pan");

    int px = 9999, py = -9999;
    mr_nav_pan_clamp(960, 1440, 480, 720, &px, &py);
    CHECK(px == 240 && py == -360, "pan clamp %d,%d", px, py);
    px = 10; py = 20;
    mr_nav_pan_clamp(480, 720, 480, 720, &px, &py);
    CHECK(px == 0 && py == 0, "pan clamp no overflow");

    CHECK(mr_nav_fit_next(MR_FIT_WIDTH) == MR_FIT_HEIGHT, "fit cycle w->h");
    CHECK(mr_nav_fit_next(MR_FIT_HEIGHT) == MR_FIT_ORIGINAL, "fit cycle h->o");
    CHECK(mr_nav_fit_next(MR_FIT_ORIGINAL) == MR_FIT_WIDTH, "fit cycle o->w");
    CHECK(mr_nav_fit_next(99) == MR_FIT_WIDTH, "fit cycle bad");
}

/* ============================================================ */
/* R3 图片头探测                                                 */
/* ============================================================ */
static void test_probe(void)
{
    char tmpl[] = "./mr_reader_probe_XXXXXX";
    char *root = mkdtemp(tmpl);
    CHECK(root != NULL, "mkdtemp probe");
    if (!root) return;

    char p[MR_PATH_MAX];
    int w = 0, h = 0;
    snprintf(p, sizeof p, "%s/a.png", root);
    write_png(p, 1234, 5678);
    CHECK(mr_probe_size(p, &w, &h) == 1 && w == 1234 && h == 5678, "probe png %dx%d", w, h);

    snprintf(p, sizeof p, "%s/a.jpg", root);
    write_jpeg(p, 1600, 2400);
    CHECK(mr_probe_size(p, &w, &h) == 1 && w == 1600 && h == 2400, "probe jpeg %dx%d", w, h);

    snprintf(p, sizeof p, "%s/a.bmp", root);
    write_bmp(p, 640, 480);
    CHECK(mr_probe_size(p, &w, &h) == 1 && w == 640 && h == 480, "probe bmp %dx%d", w, h);

    snprintf(p, sizeof p, "%s/notes.txt", root);
    touch_file(p);
    CHECK(mr_probe_size(p, &w, &h) == 0 && w == 0 && h == 0, "probe unknown");
    CHECK(mr_probe_size("/no/such/file.png", &w, &h) == 0, "probe missing");
    CHECK(mr_probe_size(NULL, &w, &h) == 0, "probe NULL");

    rm_rf(root);
}

/* ============================================================ */
/* R6 阅读方向状态                                               */
/* ============================================================ */
static void test_direction_state(void)
{
    mr_reader_set_direction(MR_DIR_RTL);
    CHECK(mr_reader_get_direction() == MR_DIR_RTL, "default RTL");
    mr_reader_set_direction(MR_DIR_LTR);
    CHECK(mr_reader_get_direction() == MR_DIR_LTR, "switch LTR");
    mr_reader_set_direction(42);
    CHECK(mr_reader_get_direction() == MR_DIR_LTR, "invalid ignored");
    mr_reader_set_direction(MR_DIR_RTL);
}

int main(void)
{
    test_contract();
    test_empty_and_bad();
    test_probe();
    test_direction_nav();
    test_fit_zoom_pan();
    test_direction_state();
    printf("%s: %d passed, %d failed\n", g_fail ? "FAIL" : "PASS", g_pass, g_fail);
    return g_fail ? 1 : 0;
}