/* app/shelf.c — 书架：扫 TF 卡 `Books/`，识别 TXT/FB2/EPUB/MOBI/CBZ（R1 仅 TXT 可开，
 * 其它显示「R2 支持」占位）；卡片列表 + 最近阅读置顶（按 progress ts 降序）。
 * 用 W_LISTVIEW（结构化列表）+ App 自绘标题。空态=清屏提示。
 */
#include "../reader_internal.h"
#include "progress.h"
#include <dirent.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>

#define SHELF_LIST_X 0
#define SHELF_LIST_Y 64
#define SHELF_LIST_W 480
#define SHELF_LIST_H (720 - 64)

typedef struct shelf_book {
    char  path[400];
    char  title[128];
    char  sub[160];
    int   fmt;          /* 0 txt,1 fb2,2 epub,3 mobi,4 cbz */
    long  size;
    uint64_t ts;        /* 最近阅读 unix；无=0 */
} shelf_book;

static shelf_book g_books[256];
static int        g_nbooks;
static int        g_active;
static meow_widget *g_list;
static uint32_t    g_bg, g_fg, g_dim;
static char        g_notice[160];   /* 空态/提示 */
static int         g_notice_ms;     /* 剩余显示 ms（0=无） */

static const char *fmt_name(int f)
{
    switch (f) { case 0: return "TXT"; case 1: return "FB2"; case 2: return "EPUB";
                 case 3: return "MOBI"; case 4: return "CBZ"; default: return "?"; }
}
static int fmt_from_ext(const char *name)
{
    const char *d = strrchr(name, '.');
    if (!d) return -1;
    if (strcasecmp(d, ".txt") == 0) return 0;
    if (strcasecmp(d, ".fb2") == 0) return 1;
    if (strcasecmp(d, ".epub") == 0) return 2;
    if (strcasecmp(d, ".mobi") == 0) return 3;
    if (strcasecmp(d, ".cbz") == 0) return 4;
    return -1;
}
static void fmt_size(char *out, int outsz, long s)
{
    if (s >= 1 << 20) snprintf(out, outsz, "%.1fMB", (double)s / (1 << 20));
    else if (s >= 1 << 10) snprintf(out, outsz, "%.0fKB", (double)s / (1 << 10));
    else snprintf(out, outsz, "%ldB", s);
}

static int cmp_recent_then_name(const void *a, const void *b)
{
    const shelf_book *x = (const shelf_book *)a, *y = (const shelf_book *)b;
    if (x->ts != y->ts) return (x->ts < y->ts) ? 1 : -1;   /* 最近在前 */
    return strcasecmp(x->title, y->title);
}

static void scan_books(void)
{
    const char *dir = READER_SD_ROOT "/Books";
    g_nbooks = 0;
    DIR *dp = opendir(dir);
    if (!dp) {
        snprintf(g_notice, sizeof g_notice, "未找到 %s 目录，请放入书籍（TXT）", dir);
        g_notice_ms = 4000;
        return;
    }
    struct dirent *de;
    while ((de = readdir(dp)) && g_nbooks < 256) {
        if (de->d_name[0] == '.') continue;
        int f = fmt_from_ext(de->d_name);
        if (f < 0) continue;
        shelf_book *b = &g_books[g_nbooks];
        if (snprintf(b->path, sizeof b->path, "%s/%s", dir, de->d_name) >= (int)sizeof b->path) continue;
        strncpy(b->title, de->d_name, sizeof b->title - 1); b->title[sizeof b->title - 1] = 0;
        char *dot = strrchr(b->title, '.');
        if (dot) *dot = 0;                     /* 标题去扩展名 */
        b->fmt = f;
        struct stat st;
        b->size = (stat(b->path, &st) == 0) ? (long)st.st_size : 0;
        rdprog p;
        b->ts = (rdprog_load(b->path, &p) == 1) ? p.ts : 0;
        char sz[24]; fmt_size(sz, sizeof sz, b->size);
        snprintf(b->sub, sizeof b->sub, "%s  ·  %s%s", fmt_name(f), sz,
                 b->ts ? "  ·  读" : "");
        g_nbooks++;
    }
    closedir(dp);
    qsort(g_books, (size_t)g_nbooks, sizeof(shelf_book), cmp_recent_then_name);
}

/* listview 行源 */
static int shelf_list_src(int idx, meow_list_item *out, void *ctx)
{
    (void)ctx;
    if (idx < 0 || idx >= g_nbooks) return 0;
    const shelf_book *b = &g_books[idx];
    out->icon_kind = MEOW_LIST_ICON_FILE;
    out->title = b->title;
    out->subtitle = b->sub;
    out->right = MEOW_LIST_RIGHT_ARROW;
    out->enabled = 1;
    out->on = 0;
    return 1;
}

static void shelf_list_tapcb(int idx, int op, void *ctx)
{
    (void)op; (void)ctx;
    if (idx < 0 || idx >= g_nbooks) return;
    const shelf_book *b = &g_books[idx];
    if (b->fmt == 0) { reader_open(b->path); }
    else { snprintf(g_notice, sizeof g_notice, "%s 格式 R2 支持（R1 先看 TXT）", fmt_name(b->fmt)); g_notice_ms = 2500; }
}

/* view 生命周期 */
static void shelf_on_create(meow_view *v, void *ctx) { (void)v; (void)ctx; }
static void shelf_on_enter(meow_view *v, void *ctx)
{
    (void)v; (void)ctx;
    g_active = 1;
    scan_books();                     /* 回到书架即重扫（新增/最近读置顶刷新） */
    const meow_theme *th = meow_theme_get();
    g_bg = th->bg; g_fg = th->fg; g_dim = th->dim;
    /* 无控件时重建列表（首次/回到书架） */
    if (g_list) { meow_widget_free(g_list); g_list = NULL; }
    g_list = meow_listview_create(SHELF_LIST_X, SHELF_LIST_Y, SHELF_LIST_W, SHELF_LIST_H,
                                  g_nbooks, shelf_list_src, NULL, MEOW_LIST_SEL_SINGLE);
    meow_listview_set_on_tap(g_list, shelf_list_tapcb, NULL);
    shelf_redraw();
}
static void shelf_on_leave(meow_view *v, void *ctx) { (void)v; (void)ctx; g_active = 0; }
static void shelf_on_destroy(meow_view *v, void *ctx)
{
    (void)v; (void)ctx;
    if (g_list) { meow_widget_free(g_list); g_list = NULL; }
}

meow_view *shelf_view_create(void)
{
    static meow_view_hooks hooks = { shelf_on_create, shelf_on_enter, shelf_on_leave,
                                     shelf_on_destroy, NULL, NULL, NULL };
    return meow_view_create(ACT_SHELF, MEOW_VIEW_ACTIVITY, &hooks, NULL);
}

int shelf_is_active(void) { return g_active; }

void shelf_redraw(void)
{
    const meow_theme *th = meow_theme_get();
    g_bg = th->bg; g_fg = th->fg; g_dim = th->dim;
    meow_ui_clear(g_bg);
    meow_ui_text(20, 22, "书架", 28, g_fg);
    /* 副标题：格式化说明 */
    char sub[96]; snprintf(sub, sizeof sub, "Books/ · %d 本", g_nbooks);
    meow_ui_text(20, 24 + 34, sub, 20, g_dim);

    if (g_list) meow_widget_draw(g_list);
    if (g_nbooks == 0) {
        meow_ui_text(30, 320, "书架为空：请往 TF 卡 Books/ 放书籍", 20, g_dim);
        meow_ui_text(30, 348, "支持 TXT（可读） / FB2 / EPUB / MOBI / CBZ（R2）", 20, g_dim);
    }
    if (g_notice_ms > 0) {
        meow_ui_fill_rect(0, 620, 480, 44, g_bg);
        meow_ui_text(20, 630, g_notice, 20, th->primary);
    }
    meow_ui_flush();
}

int shelf_on_tap(int x, int y)
{
    if (g_list && g_nbooks > 0) {
        int idx = meow_listview_tap_at(g_list, x, y);
        if (idx >= 0) { shelf_redraw(); return 1; }   /* 选中已由 SDK 标脏；重绘 */
    }
    return 0;
}