feat(box3): touch gamebook (tap to choose)

Context:
The Freenove gamebook is screen+buttons, the PLIP is audio+dial. The
ESP32-S3-BOX-3 has a 320x240 touchscreen, so its natural format is a
tap-to-choose "livre dont tu es le heros": read the passage on screen,
tap a choice button to navigate.

Approach:
A new gamebook module reuses the same SD pack as the master (the JSON
passages already carry screen/text/choices[label,goto]) and builds the
UI on the already-running LVGL stack: a scrollable column with the
title, the wrapped passage text, and one tappable button per choice.

Changes:
- New gamebook.c/.h: mounts the SD (bsp_sdcard_mount), reads
  /sdcard/gamebook/{library.json, <id>.json}, shows a story list, then
  per passage renders title + text + choice buttons; tapping a choice
  goes to its target, an ending offers "back to menu". cJSON runs on
  PSRAM hooks (the expanded books are ~80 KB JSON); LVGL calls are
  wrapped in bsp_display_lock at init (button callbacks already run in
  the LVGL task).
- main.c: call gamebook_init() after the scenario server is up; it
  takes over the screen when a pack is on the SD, else no-op (the phone
  UI stays).
- CMakeLists: build gamebook.c.

Impact:
With a JSON pack on its SD, the BOX-3 is a touch gamebook: tap a story,
tap your choices. Text-only (no audio needed). Hardware-validated:
boots into a 6-story touch library.

box3_voice/main/CMakeLists.txt

@@ -1,5 +1,5 @@
 idf_component_register(
-    SRCS "main.c" "voice_ws_client.c" "scenario_server.c" "plip_virtual.c" "plip_ui.c" "stimulus.c" "cmd_exec.c"
+    SRCS "main.c" "voice_ws_client.c" "scenario_server.c" "plip_virtual.c" "plip_ui.c" "stimulus.c" "cmd_exec.c" "gamebook.c"
     INCLUDE_DIRS "."
     PRIV_REQUIRES
         driver

box3_voice/main/gamebook.c

@@ -0,0 +1,223 @@
+// gamebook.c — see gamebook.h. Touch CYOA for the ESP32-S3-BOX-3.
+#include "gamebook.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "cJSON.h"
+#include "esp_log.h"
+#include "esp_heap_caps.h"
+
+#include "bsp/esp-bsp.h"
+#include "lvgl.h"
+
+static const char *TAG = "gamebook";
+
+#define GB_DIR      "/sdcard/gamebook"
+#define GB_LIBRARY  GB_DIR "/library.json"
+#define GB_JSON_MAX (256 * 1024)        // expanded books are ~80 KB of JSON
+
+// Colours (Workbench-ish palette).
+#define COL_BG     0x101820
+#define COL_TITLE  0xFFCC55
+#define COL_TEXT   0xF0F0F0
+#define COL_BTN    0x224466
+
+static cJSON   *s_lib_root  = NULL;     // owns library.json
+static cJSON   *s_lib       = NULL;     // borrowed: root->"library"
+static int      s_lib_n     = 0;
+
+static cJSON   *s_book      = NULL;     // owns the current <id>.json
+static cJSON   *s_passages  = NULL;     // borrowed: book->"passages"
+
+static lv_obj_t *s_root     = NULL;     // scrollable full-screen column
+
+// ── PSRAM allocators for cJSON (book trees are large) ───────────────────────
+static void *gb_malloc(size_t sz) { return heap_caps_malloc(sz, MALLOC_CAP_SPIRAM); }
+static void  gb_free(void *p)      { heap_caps_free(p); }
+
+static cJSON *load_json(const char *path)
+{
+    FILE *f = fopen(path, "rb");
+    if (!f) { ESP_LOGW(TAG, "open %s failed", path); return NULL; }
+    fseek(f, 0, SEEK_END);
+    long sz = ftell(f);
+    rewind(f);
+    if (sz <= 0 || sz > GB_JSON_MAX) { fclose(f); ESP_LOGW(TAG, "%s size %ld", path, sz); return NULL; }
+    char *buf = heap_caps_malloc((size_t)sz + 1, MALLOC_CAP_SPIRAM);
+    if (!buf) { fclose(f); return NULL; }
+    size_t rd = fread(buf, 1, (size_t)sz, f);
+    fclose(f);
+    buf[rd] = '\0';
+    cJSON *root = cJSON_Parse(buf);
+    heap_caps_free(buf);
+    if (!root) ESP_LOGW(TAG, "malformed JSON: %s", path);
+    return root;
+}
+
+// ── Root container (created once, cleared per view) ─────────────────────────
+// All UI functions below assume the LVGL lock is held (gamebook_init takes it;
+// button callbacks already run inside the LVGL task / lock).
+static void ensure_root(void)
+{
+    if (s_root) { lv_obj_clean(s_root); return; }
+    lv_obj_t *scr = lv_screen_active();
+    s_root = lv_obj_create(scr);
+    lv_obj_set_size(s_root, LV_PCT(100), LV_PCT(100));
+    lv_obj_set_pos(s_root, 0, 0);
+    lv_obj_set_style_bg_color(s_root, lv_color_hex(COL_BG), 0);
+    lv_obj_set_style_bg_opa(s_root, LV_OPA_COVER, 0);
+    lv_obj_set_style_border_width(s_root, 0, 0);
+    lv_obj_set_style_radius(s_root, 0, 0);
+    lv_obj_set_style_pad_all(s_root, 8, 0);
+    lv_obj_set_style_pad_row(s_root, 8, 0);
+    lv_obj_set_flex_flow(s_root, LV_FLEX_FLOW_COLUMN);
+    lv_obj_set_scroll_dir(s_root, LV_DIR_VER);
+}
+
+static lv_obj_t *add_title(const char *txt)
+{
+    lv_obj_t *l = lv_label_create(s_root);
+    lv_obj_set_style_text_font(l, &lv_font_montserrat_24, 0);
+    lv_obj_set_style_text_color(l, lv_color_hex(COL_TITLE), 0);
+    lv_label_set_long_mode(l, LV_LABEL_LONG_WRAP);
+    lv_obj_set_width(l, LV_PCT(100));
+    lv_label_set_text(l, txt);
+    return l;
+}
+
+static lv_obj_t *add_text(const char *txt)
+{
+    lv_obj_t *l = lv_label_create(s_root);
+    lv_obj_set_style_text_font(l, &lv_font_montserrat_14, 0);
+    lv_obj_set_style_text_color(l, lv_color_hex(COL_TEXT), 0);
+    lv_label_set_long_mode(l, LV_LABEL_LONG_WRAP);
+    lv_obj_set_width(l, LV_PCT(100));
+    lv_label_set_text(l, txt);
+    return l;
+}
+
+static lv_obj_t *add_button(const char *txt, lv_event_cb_t cb, void *user)
+{
+    lv_obj_t *b = lv_button_create(s_root);
+    lv_obj_set_width(b, LV_PCT(100));
+    lv_obj_set_style_bg_color(b, lv_color_hex(COL_BTN), 0);
+    lv_obj_set_style_pad_all(b, 10, 0);
+    lv_obj_add_event_cb(b, cb, LV_EVENT_CLICKED, user);
+    lv_obj_t *l = lv_label_create(b);
+    lv_obj_set_style_text_font(l, &lv_font_montserrat_14, 0);
+    lv_label_set_long_mode(l, LV_LABEL_LONG_WRAP);
+    lv_obj_set_width(l, LV_PCT(100));
+    lv_label_set_text(l, txt);
+    return b;
+}
+
+// Forward decls
+static void show_library(void);
+static void enter_passage(const char *pid);
+
+static void tile_cb(lv_event_t *e);
+static void choice_cb(lv_event_t *e);
+static void menu_cb(lv_event_t *e);
+
+// ── Library menu ────────────────────────────────────────────────────────────
+static void show_library(void)
+{
+    if (s_book) { cJSON_Delete(s_book); s_book = NULL; s_passages = NULL; }
+    ensure_root();
+    add_title("Choisis ton histoire");
+    for (int i = 0; i < s_lib_n; i++) {
+        const cJSON *t = cJSON_GetObjectItem(cJSON_GetArrayItem(s_lib, i), "title");
+        add_button(cJSON_IsString(t) ? t->valuestring : "?",
+                   tile_cb, (void *)(intptr_t)i);
+    }
+    lv_obj_scroll_to_y(s_root, 0, LV_ANIM_OFF);
+}
+
+// ── Passage ─────────────────────────────────────────────────────────────────
+static void enter_passage(const char *pid)
+{
+    const cJSON *p = cJSON_GetObjectItem(s_passages, pid);
+    if (!cJSON_IsObject(p)) { ESP_LOGW(TAG, "passage '%s' missing", pid); return; }
+    const cJSON *screen  = cJSON_GetObjectItem(p, "screen");
+    const cJSON *text    = cJSON_GetObjectItem(p, "text");
+    const cJSON *choices = cJSON_GetObjectItem(p, "choices");
+
+    ensure_root();
+    add_title(cJSON_IsString(screen) ? screen->valuestring : "");
+    add_text(cJSON_IsString(text) ? text->valuestring : "");
+    int n = cJSON_IsArray(choices) ? cJSON_GetArraySize(choices) : 0;
+    if (n == 0) {
+        add_button("Revenir au menu", menu_cb, NULL);
+    } else {
+        for (int i = 0; i < n; i++) {
+            const cJSON *c = cJSON_GetArrayItem(choices, i);
+            const cJSON *lbl = cJSON_GetObjectItem(c, "label");
+            const cJSON *g   = cJSON_GetObjectItem(c, "goto");
+            // goto valuestring stays valid while s_book is alive → use as user_data
+            add_button(cJSON_IsString(lbl) ? lbl->valuestring : "?",
+                       choice_cb, cJSON_IsString(g) ? g->valuestring : NULL);
+        }
+    }
+    lv_obj_scroll_to_y(s_root, 0, LV_ANIM_OFF);
+    ESP_LOGI(TAG, "passage '%s' (%d choices)", pid, n);
+}
+
+static void load_book(int idx)
+{
+    const cJSON *e = cJSON_GetArrayItem(s_lib, idx);
+    const cJSON *file = cJSON_GetObjectItem(e, "book");
+    if (!cJSON_IsString(file)) return;
+    char path[128];
+    snprintf(path, sizeof(path), "%s/%s", GB_DIR, file->valuestring);
+    cJSON *book = load_json(path);
+    if (!book) return;
+    const cJSON *passages = cJSON_GetObjectItem(book, "passages");
+    const cJSON *start = cJSON_GetObjectItem(book, "start");
+    if (!cJSON_IsObject(passages) || !cJSON_IsString(start)) {
+        cJSON_Delete(book); return;
+    }
+    if (s_book) cJSON_Delete(s_book);
+    s_book = book;
+    s_passages = (cJSON *)passages;
+    ESP_LOGI(TAG, "load book #%d @ '%s'", idx, start->valuestring);
+    enter_passage(start->valuestring);
+}
+
+// ── Touch callbacks (run inside the LVGL task → lock already held) ───────────
+static void tile_cb(lv_event_t *e)   { load_book((int)(intptr_t)lv_event_get_user_data(e)); }
+static void menu_cb(lv_event_t *e)   { (void)e; show_library(); }
+static void choice_cb(lv_event_t *e)
+{
+    const char *goto_id = (const char *)lv_event_get_user_data(e);
+    if (goto_id) enter_passage(goto_id);
+}
+
+// ── Public init ─────────────────────────────────────────────────────────────
+void gamebook_init(void)
+{
+    cJSON_Hooks hooks = { .malloc_fn = gb_malloc, .free_fn = gb_free };
+    cJSON_InitHooks(&hooks);   // keep the big book trees in PSRAM
+
+    if (bsp_sdcard_mount() != ESP_OK) {
+        ESP_LOGW(TAG, "no SD card — gamebook disabled");
+        return;
+    }
+    s_lib_root = load_json(GB_LIBRARY);
+    if (!s_lib_root) { ESP_LOGW(TAG, "no library.json — gamebook disabled"); return; }
+    s_lib = cJSON_GetObjectItem(s_lib_root, "library");
+    if (!cJSON_IsArray(s_lib) || cJSON_GetArraySize(s_lib) == 0) {
+        cJSON_Delete(s_lib_root); s_lib_root = NULL; s_lib = NULL;
+        ESP_LOGW(TAG, "empty library");
+        return;
+    }
+    s_lib_n = cJSON_GetArraySize(s_lib);
+
+    bsp_display_brightness_set(80);
+    if (bsp_display_lock(1000)) {
+        show_library();
+        bsp_display_unlock();
+    }
+    ESP_LOGI(TAG, "touch gamebook up (%d stories)", s_lib_n);
+}

box3_voice/main/gamebook.h

@@ -0,0 +1,27 @@
+#pragma once
+// gamebook — "livre dont tu es le héros" TACTILE pour l'ESP32-S3-BOX-3.
+//
+// Écran 320x240 + tactile : on lit le passage à l'écran et on TOUCHE un bouton
+// pour choisir. Réutilise le pack gamebook du master sur la SD :
+//   /sdcard/gamebook/{library.json, <id>.json}
+// où chaque passage porte {screen, text, choices:[{label, goto}]} (le champ
+// "wav" éventuel est ignoré — version texte/tactile, pas d'audio requis).
+//
+// S'appuie sur la stack LVGL déjà démarrée par bsp_display_start() : on
+// construit une UUI (menu d'histoires en liste, puis pages tactiles) et la
+// navigation se fait dans les callbacks de boutons LVGL. 100% local, hors-ligne.
+
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// Monte la SD, charge la bibliothèque et affiche le menu tactile des histoires.
+// À appeler une fois depuis app_main, après bsp_display_start() et le serveur
+// de fichiers (pour que la SD soit accessible). No-op si aucun pack présent.
+void gamebook_init(void);
+
+#ifdef __cplusplus
+}
+#endif

box3_voice/main/main.c

@@ -28,6 +28,7 @@
 #include "scenario_server.h"
 #include "plip_virtual.h"
 #include "plip_ui.h"
+#include "gamebook.h"
 #include "stimulus.h"
 #include "scenario_mesh.h"
 #include "cmd_exec.h"
@@ -463,6 +464,11 @@ void app_main(void)
         } else {
             ESP_LOGW(TAG, "stimulus_init failed — QR/melody generator off");
         }
+
+        /* Touch gamebook: if a story pack is on the SD (/sdcard/gamebook/),
+         * take over the screen with a tap-to-choose "livre dont tu es le
+         * héros". No-op (and the phone UI stays) when no pack is present. */
+        gamebook_init();
     }
 
     /* Start the ESP-NOW receiver so the master can relay scenarios to us even

idf_zacus/components/display_ui/display_ui.cpp

@@ -255,9 +255,12 @@ static lv_obj_t *s_gb_title;          // page title, top
 static lv_obj_t *s_gb_body;           // full passage text, wrapped
 static lv_obj_t *s_gb_menu;           // choice lines, bottom
 static volatile bool s_gamebook_open = false;
+static lv_obj_t *s_gb_body_cont;      // scrollable container holding s_gb_body
 static char s_gb_title_buf[64];
 static char s_gb_body_buf[1100];
 static char s_gb_menu_buf[160];
+static volatile int  s_gb_scroll_req = 0;   // pending scroll: +pages down / -pages up
+static volatile bool s_gb_scroll_home = false;  // reset scroll to top on new passage
 
 // ── Gamebook library (tile grid) ────────────────────────────────────────────
 #define LIB_TILES 6
@@ -824,39 +827,49 @@ static void build_gamebook_screen(void) {
     lv_obj_set_style_bg_color(s_scr_gamebook, lv_color_hex(0x000000), 0);
     lv_obj_set_style_bg_opa(s_scr_gamebook, LV_OPA_COVER, 0);
 
+    // Compact title line at the very top.
     s_gb_title = lv_label_create(s_scr_gamebook);
-    lv_obj_set_style_text_color(s_gb_title, lv_color_hex(COL_VALUE), 0);
-    lv_obj_set_style_text_font(s_gb_title, &lv_font_montserrat_24, 0);
+    lv_obj_set_style_text_color(s_gb_title, lv_color_hex(COL_CODE), 0);
+    lv_obj_set_style_text_font(s_gb_title, &lv_font_montserrat_14, 0);
     lv_label_set_long_mode(s_gb_title, LV_LABEL_LONG_DOT);
-    lv_obj_set_width(s_gb_title, DUI_HOR_RES - 16);
+    lv_obj_set_width(s_gb_title, DUI_HOR_RES - 12);
     lv_obj_set_style_text_align(s_gb_title, LV_TEXT_ALIGN_CENTER, 0);
     lv_label_set_text(s_gb_title, "");
-    lv_obj_align(s_gb_title, LV_ALIGN_TOP_MID, 0, 6);
+    lv_obj_align(s_gb_title, LV_ALIGN_TOP_MID, 0, 4);
 
-    // Body band: top area, height-bounded so it can never run into the menu.
-    s_gb_body = lv_label_create(s_scr_gamebook);
-    lv_obj_set_style_text_color(s_gb_body, lv_color_hex(COL_VALUE), 0);
-    lv_obj_set_style_text_font(s_gb_body, &lv_font_montserrat_14, 0);
-    // Wrap to width AND scroll vertically so long passages are never clipped:
-    // the whole text scrolls slowly through the band while the WAV narrates it.
-    lv_label_set_long_mode(s_gb_body, LV_LABEL_LONG_SCROLL_CIRCULAR);
-    lv_obj_set_size(s_gb_body, DUI_HOR_RES - 24, 196);
-    lv_label_set_text(s_gb_body, "");
-    lv_obj_align(s_gb_body, LV_ALIGN_TOP_LEFT, 12, 44);
-
-    // Menu band: reserved strip at the bottom, drawn last (foreground), with a
-    // faint background so the choices stand out from the body text.
+    // Choice selector: a single line pinned at the very bottom. Left/Right cycle
+    // the selection, click confirms. Drawn last (foreground).
     s_gb_menu = lv_label_create(s_scr_gamebook);
     lv_obj_set_style_text_color(s_gb_menu, lv_color_hex(COL_CODE), 0);
-    lv_obj_set_style_bg_color(s_gb_menu, lv_color_hex(0x101820), 0);
+    lv_obj_set_style_bg_color(s_gb_menu, lv_color_hex(0x182230), 0);
     lv_obj_set_style_bg_opa(s_gb_menu, LV_OPA_COVER, 0);
-    lv_obj_set_style_pad_all(s_gb_menu, 6, 0);
+    lv_obj_set_style_pad_all(s_gb_menu, 5, 0);
     lv_obj_set_style_text_font(s_gb_menu, &lv_font_montserrat_14, 0);
-    lv_label_set_long_mode(s_gb_menu, LV_LABEL_LONG_WRAP);
+    lv_label_set_long_mode(s_gb_menu, LV_LABEL_LONG_DOT);
     lv_obj_set_width(s_gb_menu, DUI_HOR_RES);
+    lv_obj_set_style_text_align(s_gb_menu, LV_TEXT_ALIGN_CENTER, 0);
     lv_label_set_text(s_gb_menu, "");
-    lv_obj_align(s_gb_menu, LV_ALIGN_BOTTOM_LEFT, 0, 0);
-    lv_obj_move_foreground(s_gb_menu);
+    lv_obj_align(s_gb_menu, LV_ALIGN_BOTTOM_MID, 0, 0);
+
+    // Reading area: a vertically-scrollable container filling the whole height
+    // between the title and the choice line. Up/Down scroll it by half-pages.
+    s_gb_body_cont = lv_obj_create(s_scr_gamebook);
+    lv_obj_set_style_bg_color(s_gb_body_cont, lv_color_hex(0x000000), 0);
+    lv_obj_set_style_bg_opa(s_gb_body_cont, LV_OPA_COVER, 0);
+    lv_obj_set_style_border_width(s_gb_body_cont, 0, 0);
+    lv_obj_set_style_pad_all(s_gb_body_cont, 6, 0);
+    lv_obj_set_size(s_gb_body_cont, DUI_HOR_RES, 264);   // 24 (title) .. 288 (menu)
+    lv_obj_set_pos(s_gb_body_cont, 0, 24);
+    lv_obj_set_scroll_dir(s_gb_body_cont, LV_DIR_VER);
+    lv_obj_set_scrollbar_mode(s_gb_body_cont, LV_SCROLLBAR_MODE_AUTO);
+
+    s_gb_body = lv_label_create(s_gb_body_cont);
+    lv_obj_set_style_text_color(s_gb_body, lv_color_hex(COL_VALUE), 0);
+    lv_obj_set_style_text_font(s_gb_body, &lv_font_montserrat_14, 0);
+    lv_label_set_long_mode(s_gb_body, LV_LABEL_LONG_WRAP);
+    lv_obj_set_width(s_gb_body, DUI_HOR_RES - 24);   // container width minus padding
+    lv_label_set_text(s_gb_body, "");
+    lv_obj_align(s_gb_body, LV_ALIGN_TOP_LEFT, 0, 0);
 }
 
 static void build_status_screen(void) {
@@ -951,11 +964,22 @@ static void apply_status(const display_status_t *s) {
     // Active step → scene view; idle → status view. The 5-way buttons can
     // override (1=force status, 2=force scene; 0=auto). Fade 240 ms, the
     // original ui_manager default transition (SceneTransition::kFade, 240).
-    // Gamebook page: refresh its labels from the latest show() buffers.
+    // Gamebook page: refresh its labels from the latest show() buffers, then
+    // apply any pending manual scroll (Up/Down) on the reading container.
     if (s_gamebook_open) {
         lv_label_set_text(s_gb_title, s_gb_title_buf);
         lv_label_set_text(s_gb_body,  s_gb_body_buf);
         lv_label_set_text(s_gb_menu,  s_gb_menu_buf);
+        if (s_gb_scroll_home) {
+            lv_obj_scroll_to_y(s_gb_body_cont, 0, LV_ANIM_OFF);
+            s_gb_scroll_home = false;
+        }
+        int req = s_gb_scroll_req;
+        if (req != 0) {
+            s_gb_scroll_req = 0;
+            // +1 page = read further down (content moves up): negative dy.
+            lv_obj_scroll_by(s_gb_body_cont, 0, -req * 130, LV_ANIM_ON);
+        }
     }
     // Library grid: refresh tile titles + highlight the selected one.
     if (s_library_open) {
@@ -1280,18 +1304,27 @@ extern "C" void display_ui_set_key_hook(display_ui_key_hook_t hook) {
 }
 
 extern "C" void display_ui_gamebook_show(const char *title, const char *body,
-                                         const char *menu) {
+                                         const char *menu, bool reset_scroll) {
     if (s_mutex) xSemaphoreTake(s_mutex, portMAX_DELAY);
     snprintf(s_gb_title_buf, sizeof(s_gb_title_buf), "%s", title ? title : "");
     snprintf(s_gb_body_buf,  sizeof(s_gb_body_buf),  "%s", body  ? body  : "");
     snprintf(s_gb_menu_buf,  sizeof(s_gb_menu_buf),  "%s", menu  ? menu  : "");
+    if (reset_scroll) s_gb_scroll_home = true;   // new passage → back to top
     s_gamebook_open = true;
     s_dirty = true;
     if (s_mutex) xSemaphoreGive(s_mutex);
 }
 
+extern "C" void display_ui_gamebook_scroll(int dir) {
+    // dir > 0 : read further down ; dir < 0 : back up. Accumulated and applied
+    // on the display task (this runs on the buttons task).
+    s_gb_scroll_req += (dir > 0) ? 1 : -1;
+    s_dirty = true;
+}
+
 extern "C" void display_ui_gamebook_hide(void) {
     s_gamebook_open = false;
+    s_gb_scroll_req = 0;
     s_dirty = true;
 }
 

idf_zacus/components/display_ui/include/display_ui.h

@@ -103,7 +103,13 @@ void display_ui_set_key_hook(display_ui_key_hook_t hook);
  * @param menu   choice lines (bottom), e.g. "[OK] ...\n[<>] ..."
  */
 void display_ui_gamebook_show(const char *title, const char *body,
-                              const char *menu);
+                              const char *menu, bool reset_scroll);
+
+/**
+ * @brief Scroll the gamebook reading area (Up/Down buttons).
+ * @param dir  >0 = read further down, <0 = back up. Half-page per call.
+ */
+void display_ui_gamebook_scroll(int dir);
 
 /** @brief Leave the gamebook view and return to the normal scene/status flow. */
 void display_ui_gamebook_hide(void);

idf_zacus/components/gamebook/gamebook.c

@@ -112,8 +112,10 @@ static int cur_choice_count(void)
     return cJSON_IsArray(ch) ? cJSON_GetArraySize(ch) : 0;
 }
 
-/* (Re)draw the current page: title + wrapped text + choice list with a cursor. */
-static void render_page(void)
+/* (Re)draw the current page. `home` true = new passage (reset scroll to top);
+ * false = same passage, only the choice cursor moved (keep scroll position).
+ * The bottom line shows ONE choice with < > arrows (Left/Right cycles). */
+static void render_page(bool home)
 {
     const cJSON *p = cur_passage();
     if (!cJSON_IsObject(p)) return;
@@ -122,23 +124,25 @@ static void render_page(void)
     const cJSON *choices = cJSON_GetObjectItem(p, "choices");
     int n = cJSON_IsArray(choices) ? cJSON_GetArraySize(choices) : 0;
 
-    char menu[256];
+    char menu[160];
     if (n == 0) {
         snprintf(menu, sizeof(menu), "~ Fin ~   (clic = bibliotheque)");
     } else {
-        size_t off = 0;
-        for (int i = 0; i < n && off < sizeof(menu); i++) {
-            const cJSON *lbl = cJSON_GetObjectItem(cJSON_GetArrayItem(choices, i),
-                                                   "label");
-            off += snprintf(menu + off, sizeof(menu) - off, "%s%s\n",
-                            i == s_sel ? "> " : "  ",
-                            cJSON_IsString(lbl) ? lbl->valuestring : "?");
+        const cJSON *lbl = cJSON_GetObjectItem(cJSON_GetArrayItem(choices, s_sel),
+                                               "label");
+        const char *txt = cJSON_IsString(lbl) ? lbl->valuestring : "?";
+        if (n > 1) {
+            /* Down cycles the answer, Click validates. */
+            snprintf(menu, sizeof(menu), "%d/%d  %s   (bas / clic)",
+                     s_sel + 1, n, txt);
+        } else {
+            snprintf(menu, sizeof(menu), "%s   (clic)", txt);
         }
     }
     display_ui_gamebook_show(
         cJSON_IsString(screen) ? screen->valuestring : s_title,
         cJSON_IsString(text)   ? text->valuestring   : "",
-        menu);
+        menu, home);
 }
 
 static void enter_passage(const char *pid)
@@ -147,7 +151,7 @@ static void enter_passage(const char *pid)
     if (!cJSON_IsObject(p)) { ESP_LOGW(TAG, "passage '%s' not found", pid); return; }
     snprintf(s_current, sizeof(s_current), "%s", pid);
     s_sel = 0;
-    render_page();
+    render_page(true);
 
     const cJSON *wav = cJSON_GetObjectItem(p, "wav");
     if (cJSON_IsString(wav) && wav->valuestring[0]) {
@@ -191,43 +195,58 @@ static void load_book(int idx)
 
 // ── Input ─────────────────────────────────────────────────────────────────────
 
-/* Library grid nav: 2 columns. up/down = ±2 (row), left/right = ±1 (col),
- * click = open the highlighted story. Codes: 1=click 2=down 3=left 4=right
- * 5=up (5-way ladder). */
+/* MEASURED pad mapping on this hardware (ADC ladder, see calibration):
+ *   key1 = CLICK (centre, ~0 mV)
+ *   key2 = LEFT  (gauche, ~700 mV)
+ *   key4 = DOWN  (bas,    ~1350 mV)
+ *   key5 = RIGHT (droite, ~1994 mV)
+ *   key3 is never produced; the physical UP button is electrically dead
+ *   (held = no voltage change), so nothing can depend on it. */
+#define PAD_CLICK 1
+#define PAD_LEFT  2
+#define PAD_DOWN  4
+#define PAD_RIGHT 5
+
+/* Library nav: Down/Right → next tile, Left → previous, Click → open.
+ * Selection wraps, so the working buttons reach every story without Up. */
 static bool library_key(uint8_t key)
 {
-    int s = s_lib_sel;
+    if (s_lib_n <= 0) return true;
     switch (key) {
-    case 5: s -= 2; break;   /* up    */
-    case 2: s += 2; break;   /* down  */
-    case 3: s -= 1; break;   /* left  */
-    case 4: s += 1; break;   /* right */
-    case 1:                  /* click → open */
-        load_book(s_lib_sel);
-        return true;
-    default: return true;
+    case PAD_DOWN: case PAD_RIGHT:
+        s_lib_sel = (s_lib_sel + 1) % s_lib_n; render_library(); break;
+    case PAD_LEFT:
+        s_lib_sel = (s_lib_sel - 1 + s_lib_n) % s_lib_n; render_library(); break;
+    case PAD_CLICK:
+        load_book(s_lib_sel); break;
+    default: break;
     }
-    if (s >= 0 && s < s_lib_n) { s_lib_sel = s; render_library(); }
     return true;
 }
 
-/* Story nav: D-pad moves the choice cursor, click confirms. Ending + click
- * returns to the library. */
+/* Story nav (Up is dead, so it's never used):
+ *   Left  → scroll the reading text UP
+ *   Right → scroll the reading text DOWN
+ *   Down  → next answer (cycles through all choices, wraps around)
+ *   Click → validate the highlighted answer
+ * On an ending page (no choices): Left/Right still scroll, Click → library. */
 static bool story_key(uint8_t key)
 {
+    if (key == PAD_LEFT)  { display_ui_gamebook_scroll(-1); return true; }  /* scroll up   */
+    if (key == PAD_RIGHT) { display_ui_gamebook_scroll(+1); return true; }  /* scroll down */
+
     int n = cur_choice_count();
-    if (n == 0) {                       /* ending → back to library on click */
-        if (key == 1) open_library();
+    if (n == 0) {                       /* ending → click returns to library */
+        if (key == PAD_CLICK) open_library();
         return true;
     }
     switch (key) {
-    case 5: case 3: s_sel = (s_sel - 1 + n) % n; render_page(); break;  /* up/left  */
-    case 2: case 4: s_sel = (s_sel + 1) % n;     render_page(); break;  /* down/right */
-    case 1: {                           /* click → confirm */
+    case PAD_DOWN: s_sel = (s_sel + 1) % n; render_page(false); break;  /* next answer */
+    case PAD_CLICK: {                                                   /* validate */
         const cJSON *choices = cJSON_GetObjectItem(cur_passage(), "choices");
         const cJSON *g = cJSON_GetObjectItem(cJSON_GetArrayItem(choices, s_sel), "goto");
         if (cJSON_IsString(g)) {
-            ESP_LOGI(TAG, "select #%d -> '%s'", s_sel, g->valuestring);
+            ESP_LOGI(TAG, "validate #%d -> '%s'", s_sel, g->valuestring);
             enter_passage(g->valuestring);
         }
         break;

plip_voice/main/CMakeLists.txt

@@ -13,6 +13,7 @@ idf_component_register(
         "dtmf.c"
         "turn_client.c"
         "slic.c"
+        "plip_gamebook.c"
     INCLUDE_DIRS "."
     PRIV_REQUIRES
         driver

plip_voice/main/conversation.c

@@ -23,6 +23,7 @@
 #include "phone.h"
 #include "slic.h"
 #include "turn_client.h"
+#include "plip_gamebook.h"
 #if CONFIG_PLIP_DIAL_DTMF
 #include "dtmf.h"
 #endif
@@ -68,6 +69,7 @@ typedef enum {
     STATE_BUSY,
     STATE_GREET,       /* fetching + playing NPC greeting (Stage 2) */
     STATE_CONNECTED,   /* in-call — Stage 3 will add listen loop     */
+    STATE_GAMEBOOK,    /* audio "livre dont vous êtes le héros"      */
 } conv_state_t;
 
 static volatile conv_state_t s_state    = STATE_IDLE;
@@ -129,6 +131,7 @@ static void go_idle(void)
     audio_stop();
     audio_pa_set(false);
     dialer_reset();
+    plip_gamebook_end();   /* no-op if the gamebook wasn't running */
 #if CONFIG_PLIP_DIAL_DTMF
     dtmf_stop();
 #endif
@@ -185,6 +188,17 @@ static void conv_task(void *arg)
                     if (s_incoming_armed) {
                         /* INCOMING call answered (phone.c detected the edge). */
                         enter_incoming_greet();
+                    } else if (plip_gamebook_available()) {
+                        /* Gamebook phone: a story pack is on the SD → pick up
+                         * launches the audio "livre dont vous êtes le héros".
+                         * Digits dialed choose the story then the answers. */
+                        dialer_reset();
+#if CONFIG_PLIP_DIAL_DTMF
+                        dtmf_start();
+#endif
+                        plip_gamebook_begin();
+                        s_state = STATE_GAMEBOOK;
+                        ESP_LOGI(TAG, "off-hook -> GAMEBOOK");
                     } else {
                         /* Outgoing call: dial tone, wait for digits. */
                         dialer_reset();
@@ -224,6 +238,21 @@ static void conv_task(void *arg)
             }
             break;
 
+        case STATE_GAMEBOOK:
+            if (!s_offhook) {
+                go_idle();
+                break;
+            }
+            /* Each dialed digit drives one choice. Consume a single digit at a
+             * time (take the first, reset) so the player can dial again right
+             * away — even over the narration, which gets interrupted. */
+            if (!dialer_idle()) {
+                int d = dialer_current()[0] - '0';
+                dialer_reset();
+                plip_gamebook_feed_digit(d);
+            }
+            break;
+
         case STATE_DIALING:
             if (!s_offhook) {
                 go_idle();

plip_voice/main/net.c

@@ -54,8 +54,9 @@
 
 #define SPIFFS_LABEL  "storage"
 #define SPIFFS_BASE   "/spiffs"
-#define MAX_BODY      (512 * 1024)   /* streamed in 2 KB chunks → RAM-safe; raised
-                                        so full-length say() hint WAVs fit on SD */
+#define MAX_BODY      (3 * 1024 * 1024) /* streamed in 2 KB chunks → RAM-safe;
+                                          raised to fit full-length neural-TTS
+                                          (Kyutai) gamebook narration WAVs */
 
 static volatile bool    s_connected  = false;
 static httpd_handle_t   s_httpd      = NULL;

plip_voice/main/plip_gamebook.c

@@ -0,0 +1,171 @@
+// plip_gamebook.c — see plip_gamebook.h. Audio CYOA for the PLIP phone.
+#include "plip_gamebook.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "cJSON.h"
+#include "esp_log.h"
+
+#include "audio.h"
+
+static const char *TAG = "plip_gb";
+
+#define GB_DIR      "/sdcard/gamebook"
+#define GB_LIBRARY  GB_DIR "/library.json"
+#define GB_MENU_WAV GB_DIR "/menu.wav"
+#define GB_JSON_MAX (64 * 1024)
+
+typedef enum { GB_OFF, GB_MENU, GB_STORY } gb_mode_t;
+
+static cJSON   *s_lib_root  = NULL;   // owns library.json
+static cJSON   *s_lib       = NULL;   // borrowed: root->"library"
+static int      s_lib_n     = 0;
+
+static cJSON   *s_book      = NULL;   // owns the current <id>.json
+static cJSON   *s_passages  = NULL;   // borrowed: book->"passages"
+static char     s_current[48] = {0};
+
+static gb_mode_t s_mode = GB_OFF;
+
+bool plip_gamebook_active(void) { return s_mode != GB_OFF; }
+
+static cJSON *load_json(const char *path)
+{
+    FILE *f = fopen(path, "rb");
+    if (!f) { ESP_LOGW(TAG, "open %s failed", path); return NULL; }
+    fseek(f, 0, SEEK_END);
+    long sz = ftell(f);
+    rewind(f);
+    if (sz <= 0 || sz > GB_JSON_MAX) { fclose(f); return NULL; }
+    char *buf = malloc((size_t)sz + 1);
+    if (!buf) { fclose(f); return NULL; }
+    size_t rd = fread(buf, 1, (size_t)sz, f);
+    fclose(f);
+    buf[rd] = '\0';
+    cJSON *root = cJSON_Parse(buf);
+    free(buf);
+    if (!root) ESP_LOGW(TAG, "malformed JSON: %s", path);
+    return root;
+}
+
+static void play_wav(const char *file)   // file = bare name under GB_DIR
+{
+    char path[96];
+    snprintf(path, sizeof(path), "%s/%s", GB_DIR, file);
+    audio_stop();                 // interrupt any current narration
+    audio_play_async(path);
+}
+
+bool plip_gamebook_available(void)
+{
+    if (!audio_ensure_sd()) return false;
+    FILE *f = fopen(GB_LIBRARY, "rb");
+    if (!f) return false;
+    fclose(f);
+    return true;
+}
+
+static void free_story(void)
+{
+    if (s_book) { cJSON_Delete(s_book); s_book = NULL; }
+    s_passages = NULL;
+    s_current[0] = '\0';
+}
+
+static void enter_menu(void)
+{
+    free_story();
+    s_mode = GB_MENU;
+    audio_stop();
+    audio_play_async(GB_MENU_WAV);   // absolute path
+    ESP_LOGI(TAG, "menu (%d stories)", s_lib_n);
+}
+
+// Play a passage by id (its WAV narrates the text + numbered choices).
+static void enter_passage(const char *pid)
+{
+    const cJSON *p = cJSON_GetObjectItem(s_passages, pid);
+    if (!cJSON_IsObject(p)) { ESP_LOGW(TAG, "passage '%s' missing", pid); return; }
+    snprintf(s_current, sizeof(s_current), "%s", pid);
+    const cJSON *wav = cJSON_GetObjectItem(p, "wav");
+    if (cJSON_IsString(wav) && wav->valuestring[0]) play_wav(wav->valuestring);
+    const cJSON *ch = cJSON_GetObjectItem(p, "choices");
+    ESP_LOGI(TAG, "passage '%s' (%d choices)", pid,
+             cJSON_IsArray(ch) ? cJSON_GetArraySize(ch) : 0);
+}
+
+static void load_book(int idx)
+{
+    const cJSON *e = cJSON_GetArrayItem(s_lib, idx);
+    const cJSON *file = cJSON_GetObjectItem(e, "book");
+    if (!cJSON_IsString(file)) return;
+    char path[128];
+    snprintf(path, sizeof(path), "%s/%s", GB_DIR, file->valuestring);
+    cJSON *book = load_json(path);
+    if (!book) return;
+    const cJSON *passages = cJSON_GetObjectItem(book, "passages");
+    const cJSON *start = cJSON_GetObjectItem(book, "start");
+    if (!cJSON_IsObject(passages) || !cJSON_IsString(start)) {
+        cJSON_Delete(book); return;
+    }
+    free_story();
+    s_book = book;
+    s_passages = (cJSON *)passages;
+    s_mode = GB_STORY;
+    ESP_LOGI(TAG, "load book #%d @ '%s'", idx, start->valuestring);
+    enter_passage(start->valuestring);
+}
+
+void plip_gamebook_begin(void)
+{
+    plip_gamebook_end();   // clean any previous run
+
+    s_lib_root = load_json(GB_LIBRARY);
+    if (!s_lib_root) return;
+    s_lib = cJSON_GetObjectItem(s_lib_root, "library");
+    if (!cJSON_IsArray(s_lib) || cJSON_GetArraySize(s_lib) == 0) {
+        cJSON_Delete(s_lib_root); s_lib_root = NULL; s_lib = NULL;
+        return;
+    }
+    s_lib_n = cJSON_GetArraySize(s_lib);
+    audio_pa_set(true);    // earpiece amplifier on
+    enter_menu();
+}
+
+void plip_gamebook_feed_digit(int d)
+{
+    if (s_mode == GB_MENU) {
+        if (d >= 1 && d <= s_lib_n) load_book(d - 1);
+        return;
+    }
+    if (s_mode == GB_STORY) {
+        const cJSON *p = cJSON_GetObjectItem(s_passages, s_current);
+        const cJSON *ch = cJSON_GetObjectItem(p, "choices");
+        int n = cJSON_IsArray(ch) ? cJSON_GetArraySize(ch) : 0;
+        if (n == 0) {                 // ending: 0 (or any) → back to menu
+            enter_menu();
+            return;
+        }
+        if (d >= 1 && d <= n) {
+            const cJSON *g = cJSON_GetObjectItem(cJSON_GetArrayItem(ch, d - 1),
+                                                 "goto");
+            if (cJSON_IsString(g)) {
+                ESP_LOGI(TAG, "choice %d -> '%s'", d, g->valuestring);
+                enter_passage(g->valuestring);
+            }
+        }
+        // out-of-range digit: ignore (player can dial again)
+    }
+}
+
+void plip_gamebook_end(void)
+{
+    if (s_mode == GB_OFF && !s_lib_root && !s_book) return;
+    s_mode = GB_OFF;
+    audio_stop();
+    free_story();
+    if (s_lib_root) { cJSON_Delete(s_lib_root); s_lib_root = NULL; s_lib = NULL; }
+    ESP_LOGI(TAG, "ended");
+}

plip_voice/main/plip_gamebook.h

@@ -0,0 +1,44 @@
+#pragma once
+// plip_gamebook — "livre dont vous êtes le héros" AUDIO pour le téléphone PLIP.
+//
+// Pas d'écran : tout passe par l'écouteur. On décroche, le narrateur lit le
+// menu des histoires ("pour le dragon, faites le 1..."), on compose un chiffre
+// au cadran pour choisir une histoire, puis à chaque passage le narrateur lit
+// le texte ET les choix numérotés ("pour examiner la machine, faites le 1..."),
+// et on compose le chiffre du choix. Raccrocher arrête tout.
+//
+// Lit /sdcard/gamebook/{library.json, menu.wav, <id>.json, <id>_<passage>.wav}
+// (pack audio "téléphone" produit par tools/gamebook/build_phone_gamebook.py,
+// où la narration des WAV inclut déjà les invites "faites le N"). 100% local,
+// aucun modèle, aucun réseau.
+//
+// Intégration : conversation.c lance plip_gamebook_begin() au décroché (si un
+// pack est présent sur la SD), pousse chaque chiffre composé via
+// plip_gamebook_feed_digit(), et appelle plip_gamebook_end() au raccroché.
+
+#include <stdbool.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// La SD est-elle montée et un pack gamebook présent ? (à tester au décroché)
+bool plip_gamebook_available(void);
+
+// Démarre le mode livre-jeu : charge la bibliothèque et joue le menu audio.
+void plip_gamebook_begin(void);
+
+// Traite un chiffre composé (0..9). Menu → choisit l'histoire ; en histoire →
+// choisit la réponse ; sur une fin → 0 revient au menu. Interrompt la
+// narration en cours pour enchaîner.
+void plip_gamebook_feed_digit(int digit);
+
+// Quitte le mode livre-jeu (raccroché) : stoppe l'audio, libère la mémoire.
+void plip_gamebook_end(void);
+
+// Vrai tant qu'une partie est en cours.
+bool plip_gamebook_active(void);
+
+#ifdef __cplusplus
+}
+#endif