/*
 * Copyright (c) 2020 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: LicenseRef-Nordic-5-Clause
 */

#include "btstack/bluetooth.h"
#include "system/includes.h"
#include "bt_common.h"
#include "api/sig_mesh_api.h"
#include "api/scene_srv.h"
#include "misc/slist.h"
#include "misc/list_gen.h"
#include "misc/byteorder.h"
#include "model_api.h"
#include <access.h>
#include "model_utils.h"
#include "model_types.h"
#include "adaptation.h"

#if (CONFIG_BT_MESH_SCENE_SRV)

#define LOG_TAG             "[Gen_Scene_srv]"
#define LOG_ERROR_ENABLE
#define LOG_DEBUG_ENABLE
#define LOG_INFO_ENABLE
/* #define LOG_DUMP_ENABLE */
#define LOG_CLI_ENABLE
#include "debug.h"

#define SCENE_PAGE_SIZE SETTINGS_MAX_VAL_LEN
/* Account for company ID in data: */
#define VND_MODEL_SCENE_DATA_OVERHEAD sizeof(uint16_t)

struct __attribute__((__packed__)) scene_data {
    uint8_t len;
    uint8_t elem_idx;
    uint16_t id;
    uint8_t data[];
};

static sys_slist_t scene_servers;

static char *scene_path(char *buf, uint16_t scene, bool vnd, uint8_t page)
{
    sprintf(buf, "%x/%c%x", scene, vnd ? 'v' : 's', page);
    return buf;
}

static inline void update_page_count(struct bt_mesh_scene_srv *srv, bool vnd,
                                     uint8_t page)
{
    if (vnd) {
        srv->vndpages = MAX(page + 1, srv->vndpages);
    } else {
        srv->sigpages = MAX(page + 1, srv->sigpages);
    }
}

static const struct bt_mesh_scene_entry *
entry_find(const struct bt_mesh_model *mod, bool vnd)
{
    const struct bt_mesh_scene_entry *it;

    if (vnd) {
        extern const struct bt_mesh_scene_entry
            _bt_mesh_scene_entry_vnd_list_start[];
        extern const struct bt_mesh_scene_entry
            _bt_mesh_scene_entry_vnd_list_end[];

        for (it = _bt_mesh_scene_entry_vnd_list_start;
             it != _bt_mesh_scene_entry_vnd_list_end; it++) {
            if (it->id.vnd.id == mod->vnd.id &&
                it->id.vnd.company == mod->vnd.company) {
                return it;
            }
        }
    } else {
        extern const struct bt_mesh_scene_entry
            _bt_mesh_scene_entry_sig_list_start[];
        extern const struct bt_mesh_scene_entry
            _bt_mesh_scene_entry_sig_list_end[];

        for (it = _bt_mesh_scene_entry_sig_list_start;
             it != _bt_mesh_scene_entry_sig_list_end; it++) {
            if (it->id.sig == mod->id) {
                return it;
            }
        }
    }

    return NULL;
}

static struct bt_mesh_scene_srv *srv_find(uint16_t elem_idx)
{
    struct bt_mesh_scene_srv *srv = scene_servers.head;

    // 遍历链表
    while (srv != NULL) {
        /* Scene servers are added to the link list in reverse
         * composition data order. The first scene server that isn't
         * after this element will be the right one:
         */
        if (srv->model->rt->elem_idx <= elem_idx) {
            return srv;
        }
        srv = (struct bt_mesh_scene_srv *)srv->n.next;
    }

    return NULL;
}

static uint16_t current_scene(const struct bt_mesh_scene_srv *srv)
{
    if (srv->next && k_work_delayable_is_pending(&srv->work)) {
        /* When we're in a transition, the current scene should be NONE (see the Bluetooth
         * mesh model specification, section 5.1.3.2.1). Check that we're not just in a
         * delay phase:
         */
        if (!srv->transition.delay ||
            (k_ticks_to_ms_near64(k_work_delayable_remaining_get(&srv->work)) <=
             srv->transition.time)) {
            return BT_MESH_SCENE_NONE;
        } else {
            return srv->prev;
        }
    }

    return srv->prev;
}

static uint16_t target_scene(const struct bt_mesh_scene_srv *srv)
{
    return srv->next;
}

static void scene_status_encode(struct bt_mesh_scene_srv *srv, struct net_buf_simple *buf,
                                const struct bt_mesh_scene_state *state)
{
    bt_mesh_model_msg_init(buf, BT_MESH_SCENE_OP_STATUS);
    net_buf_simple_add_u8(buf, state->status);
    if (state->target != BT_MESH_SCENE_NONE) {
        net_buf_simple_add_le16(buf, state->current);
        net_buf_simple_add_le16(buf, state->target);
        net_buf_simple_add_u8(buf, model_transition_encode(state->remaining_time));
    } else {
        net_buf_simple_add_le16(buf, state->current);
    }
}

static int scene_status_send(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                             const struct bt_mesh_scene_state *state)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;

    BT_MESH_MODEL_BUF_DEFINE(buf, BT_MESH_SCENE_OP_STATUS,
                             BT_MESH_SCENE_MSG_MAXLEN_STATUS);

    scene_status_encode(srv, &buf, state);

    return bt_mesh_msg_send(model, ctx, &buf);
}

static void curr_scene_state_get(struct bt_mesh_scene_srv *srv, struct bt_mesh_scene_state *state)
{
    state->current = current_scene(srv);
    state->target = target_scene(srv);
    state->remaining_time = k_ticks_to_ms_near64(k_work_delayable_remaining_get(&srv->work));
    state->status = BT_MESH_SCENE_SUCCESS;
}

static int handle_get(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                      struct net_buf_simple *buf)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;
    struct bt_mesh_scene_state state;

    curr_scene_state_get(srv, &state);
    scene_status_send(model, ctx, &state);

    return 0;
}

static int scene_recall(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                        struct net_buf_simple *buf, bool ack)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;
    struct bt_mesh_model_transition transition;
    struct bt_mesh_scene_state state;
    uint16_t scene;
    bool has_trans;
    uint8_t tid;
    int err;

    scene = net_buf_simple_pull_le16(buf);
    if (scene == BT_MESH_SCENE_NONE) {
        return -EINVAL; /* Prohibited */
    }

    tid = net_buf_simple_pull_u8(buf);
    has_trans = !!model_transition_get(srv->model, &transition, buf);

    if (tid_check_and_update(&srv->tid, tid, ctx)) {
        log_debug("Duplicate TID");
        curr_scene_state_get(srv, &state);
        scene_status_send(model, ctx, &state);
        return 0;
    }

    err = bt_mesh_scene_srv_set(srv, scene, has_trans ? &transition : NULL);
    if (err) {
        curr_scene_state_get(srv, &state);
        if (err == -ENOENT) {
            state.status = BT_MESH_SCENE_NOT_FOUND;
        }
    } else {
        state.status = BT_MESH_SCENE_SUCCESS;
        state.current = srv->prev;
        state.target = srv->next;
        state.remaining_time = transition.time;
    }

    if (ack) {
        scene_status_send(model, ctx, &state);
    }

    if (state.status == BT_MESH_SCENE_SUCCESS) {
        /* Publish */
        scene_status_send(model, NULL, &state);
    }

    return 0;
}

static int handle_recall(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                         struct net_buf_simple *buf)
{
    return scene_recall(model, ctx, buf, true);
}

static int handle_recall_unack(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                               struct net_buf_simple *buf)
{
    return scene_recall(model, ctx, buf, false);
}

static int scene_register_status_send(struct bt_mesh_model *model,
                                      struct bt_mesh_msg_ctx *ctx,
                                      enum bt_mesh_scene_status status)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;

    BT_MESH_MODEL_BUF_DEFINE(buf, BT_MESH_SCENE_OP_REGISTER_STATUS,
                             BT_MESH_SCENE_MSG_MINLEN_REGISTER_STATUS +
                             2 * CONFIG_BT_MESH_SCENES_MAX);
    bt_mesh_model_msg_init(&buf, BT_MESH_SCENE_OP_REGISTER_STATUS);
    net_buf_simple_add_u8(&buf, status);
    net_buf_simple_add_le16(&buf, current_scene(srv));

    for (int i = 0; i < srv->count; i++) {
        net_buf_simple_add_le16(&buf, srv->all[i]);
    }

    return bt_mesh_msg_send(model, ctx, &buf);
}

static int handle_register_get(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                               struct net_buf_simple *buf)
{
    (void)scene_register_status_send(model, ctx, BT_MESH_SCENE_SUCCESS);

    return 0;
}

const struct bt_mesh_model_op _bt_mesh_scene_srv_op[] = {
    {
        BT_MESH_SCENE_OP_GET,
        BT_MESH_LEN_EXACT(BT_MESH_SCENE_MSG_LEN_GET),
        handle_get,
    },
    {
        BT_MESH_SCENE_OP_RECALL,
        BT_MESH_LEN_MIN(BT_MESH_SCENE_MSG_MINLEN_RECALL),
        handle_recall,
    },
    {
        BT_MESH_SCENE_OP_RECALL_UNACK,
        BT_MESH_LEN_MIN(BT_MESH_SCENE_MSG_MINLEN_RECALL),
        handle_recall_unack,
    },
    {
        BT_MESH_SCENE_OP_REGISTER_GET,
        BT_MESH_LEN_EXACT(BT_MESH_SCENE_MSG_LEN_REGISTER_GET),
        handle_register_get,
    },
    BT_MESH_MODEL_OP_END,
};

static uint16_t *scene_find(struct bt_mesh_scene_srv *srv, uint16_t scene)
{
    for (int i = 0; i < srv->count; i++) {
        if (srv->all[i] == scene) {
            return &srv->all[i];
        }
    }

    return NULL;
}

static void entry_recover(struct bt_mesh_scene_srv *srv, bool vnd,
                          const struct scene_data *data)
{
    const struct bt_mesh_elem *elem = &bt_mesh_comp_get()->elem[data->elem_idx];
    const size_t overhead = vnd ? VND_MODEL_SCENE_DATA_OVERHEAD : 0;
    const struct bt_mesh_scene_entry *entry;
    struct bt_mesh_model *mod;

    if (vnd) {
        mod = bt_mesh_model_find_vnd(elem, sys_get_le16(data->data), data->id);
    } else {
        mod = bt_mesh_model_find(elem, data->id);
    }

    if (!mod) {
        log_error("No model @%s", bt_hex(&data->elem_idx, vnd ? 5 : 3));
        return;
    }

    /* MeshMDL1.0.1, section 5.1.3.1.1:
     * If a model is extending another model, the extending model shall determine
     * the Stored with Scene behavior of that model.
     */
    if (bt_mesh_model_is_extended(mod)) {
        return;
    }

    entry = entry_find(mod, vnd);
    if (!entry) {
        log_error("No scene entry for %s", bt_hex(&data->elem_idx, vnd ? 5 : 3));
        return;
    }

    entry->recall(mod, &data->data[overhead], data->len - overhead,
                  &srv->transition);
}

static void page_recover(struct bt_mesh_scene_srv *srv, bool vnd,
                         const uint8_t buf[], size_t len)
{
    for (struct scene_data *data = (struct scene_data *)&buf[0];
         data < (struct scene_data *)&buf[len];
         data = (struct scene_data *)&data->data[data->len]) {
        entry_recover(srv, vnd, data);
    }
}

static ssize_t entry_store(struct bt_mesh_model *mod,
                           const struct bt_mesh_scene_entry *entry, bool vnd,
                           uint8_t buf[])
{
    struct scene_data *data = (struct scene_data *)buf;
    ssize_t size;

    data->elem_idx = mod->rt->elem_idx;

    if (vnd) {
        data->id = mod->vnd.id;
        sys_put_le16(mod->vnd.company, data->data);
        size = entry->store(mod,
                            &data->data[VND_MODEL_SCENE_DATA_OVERHEAD]);
        data->len = size + VND_MODEL_SCENE_DATA_OVERHEAD;
    } else {
        data->id = mod->id;
        size = entry->store(mod, &data->data[0]);
        data->len = size;
    }

    if (size > entry->maxlen) {
        log_error("Entry %s:%u:%u: data too large (%u bytes)",
                  vnd ? "vnd" : "sig", mod->rt->elem_idx, mod->rt->mod_idx, size);
        return -EINVAL;
    }

    if (size < 0) {
        log_error("Failed storing %s:%u:%u (%d)", vnd ? "vnd" : "sig",
                  mod->rt->elem_idx, mod->rt->mod_idx, size);
        return size;
    }

    if (size == 0) {
        /* Silently ignore this entry */
        return 0;
    }

    return sizeof(struct scene_data) + data->len;
}

/** Store a single page of the Scene.
 *
 *  To accommodate large scene data, each scene is stored in pages of up to 256
 *  bytes.
 */
static void page_store(struct bt_mesh_scene_srv *srv, uint16_t scene,
                       uint8_t page, bool vnd, uint8_t buf[], size_t len)
{
    char path[9];
    int err;

    scene_path(path, scene, vnd, page);
    update_page_count(srv, vnd, page);

    err = bt_mesh_model_data_store(srv->model, false, path, buf, len);
    if (err) {
        log_error("Failed storing %s: %d", path, err);
    }
}

/** @brief Get the end of the Scene server's controlled elements.
 *
 *  A Scene Server controls all elements whose index is equal to or larger than
 *  its own, and smaller than the return value of this function.
 *
 *  @param[in] srv Scene Server to find control boundary of.
 *
 *  @return The element index of the next Scene Server, or the total element
 *          count.
 */
static uint16_t srv_elem_end(const struct bt_mesh_scene_srv *srv)
{
    uint16_t end = bt_mesh_elem_count();
    struct bt_mesh_scene_srv *it = scene_servers.head;

    // 遍历链表
    while (it != NULL) {
        if (it == srv) {
            break;
        }

        end = it->model->rt->elem_idx;
        it = (struct bt_mesh_scene_srv *)it->n.next;
    }

    return end;
}

static void scene_recall_complete_mod(struct bt_mesh_scene_srv *srv, struct bt_mesh_model *models,
                                      int model_count, bool vnd)
{
    for (int j = 0; j < model_count; j++) {
        const struct bt_mesh_scene_entry *entry;
        struct bt_mesh_model *mod = &models[j];

        if (mod == srv->model) {
            continue;
        }

        /* MeshMDL1.0.1, section 5.1.3.1.1:
         * If a model is extending another model, the extending
         * model shall determine the Stored with Scene behavior
         * of that model.
         */
        if (bt_mesh_model_is_extended(mod)) {
            continue;
        }

        entry = entry_find(mod, vnd);
        if (!entry || !entry->recall_complete) {
            continue;
        }

        entry->recall_complete(mod);
    }
}

static void scene_recall_complete(struct bt_mesh_scene_srv *srv)
{
    const struct bt_mesh_comp *comp = bt_mesh_comp_get();
    uint16_t elem_end = srv_elem_end(srv);

    for (int i = srv->model->rt->elem_idx; i < elem_end; i++) {
        const struct bt_mesh_elem *elem = &comp->elem[i];

        scene_recall_complete_mod(srv, elem->models, elem->model_count, false);
        scene_recall_complete_mod(srv, elem->vnd_models, elem->vnd_model_count, true);
    }
}

static void scene_store_mod(struct bt_mesh_scene_srv *srv, uint16_t scene,
                            bool vnd)
{
    const size_t data_overhead = sizeof(struct scene_data) + (vnd ? 2 : 0);
    const struct bt_mesh_comp *comp = bt_mesh_comp_get();
    uint16_t elem_end = srv_elem_end(srv);
    uint8_t buf[SCENE_PAGE_SIZE];
    uint8_t page = 0;
    size_t len = 0;
    for (int i = srv->model->rt->elem_idx; i < elem_end; i++) {
        const struct bt_mesh_elem *elem = &comp->elem[i];
        struct bt_mesh_model *models = vnd ? elem->vnd_models : elem->models;
        int model_count = vnd ? elem->vnd_model_count : elem->model_count;

        for (int j = 0; j < model_count; j++) {
            const struct bt_mesh_scene_entry *entry;
            struct bt_mesh_model *mod = &models[j];
            ssize_t size;

            if (mod == srv->model) {
                continue;
            }

            /* MeshMDL1.0.1, section 5.1.3.1.1:
             * If a model is extending another model, the extending
             * model shall determine the Stored with Scene behavior
             * of that model.
             */
            if (bt_mesh_model_is_extended(mod)) {
                continue;
            }

            entry = entry_find(mod, vnd);
            if (!entry) {
                continue;
            }

            if (len + data_overhead + entry->maxlen >= SCENE_PAGE_SIZE) {
                page_store(srv, scene, page++, vnd, buf, len);
                len = 0;
            }

            size = entry_store(mod, entry, vnd, &buf[len]);
            len += MAX(0, size);
        }
    }

    if (len) {
        page_store(srv, scene, page, vnd, buf, len);
    }
}

static enum bt_mesh_scene_status scene_store(struct bt_mesh_scene_srv *srv,
        uint16_t scene)
{
    uint16_t *existing = scene_find(srv, scene);

    if (!existing) {
        if (srv->count == ARRAY_SIZE(srv->all)) {
            log_error("Out of space");
            return BT_MESH_SCENE_REGISTER_FULL;
        }

        srv->all[srv->count++] = scene;
    }

    scene_store_mod(srv, scene, false);
    scene_store_mod(srv, scene, true);

    srv->prev = scene;
    srv->next = BT_MESH_SCENE_NONE;
    /* We're checking srv->next in the handler, so failure to cancel is okay: */
    (void)k_work_cancel_delayable(&srv->work);

    return BT_MESH_SCENE_SUCCESS;
}

static void scene_delete(struct bt_mesh_scene_srv *srv, uint16_t *scene)
{
    uint8_t path[9];

    log_debug("0x%x", *scene);

    for (int i = 0; i < srv->sigpages; i++) {
        scene_path(path, *scene, false, i);
        (void)bt_mesh_model_data_store(srv->model, false, path, NULL, 0);
    }

    for (int i = 0; i < srv->vndpages; i++) {
        scene_path(path, *scene, true, i);
        (void)bt_mesh_model_data_store(srv->model, false, path, NULL, 0);
    }

    uint16_t target = target_scene(srv);
    uint16_t current = current_scene(srv);

    if (target == *scene ||
        (current == *scene && target == BT_MESH_SCENE_NONE)) {
        srv->next = BT_MESH_SCENE_NONE;
        srv->prev = BT_MESH_SCENE_NONE;

        /* Cancel failure checked in work handler. */
        (void)k_work_cancel_delayable(&srv->work);
    } else if (current == *scene && target != *scene) {
        srv->prev = BT_MESH_SCENE_NONE;
    }

    *scene = srv->all[--srv->count];
}

static int handle_store(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                        struct net_buf_simple *buf)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;
    enum bt_mesh_scene_status status;
    uint16_t scene_number;

    scene_number = net_buf_simple_pull_le16(buf);
    if (scene_number == BT_MESH_SCENE_NONE) {
        return -EINVAL;
    }

    status = scene_store(srv, scene_number);
    scene_register_status_send(model, ctx, status);

    return 0;
}

static int handle_store_unack(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                              struct net_buf_simple *buf)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;
    uint16_t scene_number;

    scene_number = net_buf_simple_pull_le16(buf);
    if (scene_number == BT_MESH_SCENE_NONE) {
        return -EINVAL;
    }

    (void)scene_store(srv, scene_number);

    return 0;
}

static int delete_scene(struct bt_mesh_scene_srv *srv, struct bt_mesh_msg_ctx *ctx,
                        struct net_buf_simple *buf)
{
    uint16_t *scene;

    scene = scene_find(srv, net_buf_simple_pull_le16(buf));
    if (scene != BT_MESH_SCENE_NONE) {
        scene_delete(srv, scene);
    }

    return 0;
}

static int handle_delete(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                         struct net_buf_simple *buf)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;
    int err;

    err = delete_scene(srv, ctx, buf);
    if (err) {
        return err;
    }

    scene_register_status_send(model, ctx, BT_MESH_SCENE_SUCCESS);

    return 0;
}

static int handle_delete_unack(struct bt_mesh_model *model, struct bt_mesh_msg_ctx *ctx,
                               struct net_buf_simple *buf)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;

    return delete_scene(srv, ctx, buf);
}

const struct bt_mesh_model_op _bt_mesh_scene_setup_srv_op[] = {
    {
        BT_MESH_SCENE_OP_STORE,
        BT_MESH_LEN_EXACT(BT_MESH_SCENE_MSG_LEN_STORE),
        handle_store,
    },
    {
        BT_MESH_SCENE_OP_STORE_UNACK,
        BT_MESH_LEN_EXACT(BT_MESH_SCENE_MSG_LEN_STORE),
        handle_store_unack,
    },
    {
        BT_MESH_SCENE_OP_DELETE,
        BT_MESH_LEN_EXACT(BT_MESH_SCENE_MSG_LEN_DELETE),
        handle_delete,
    },
    {
        BT_MESH_SCENE_OP_DELETE_UNACK,
        BT_MESH_LEN_EXACT(BT_MESH_SCENE_MSG_LEN_DELETE),
        handle_delete_unack,
    },
    BT_MESH_MODEL_OP_END,
};

// static void scene_srv_transition_end(struct k_work *work)
// {
// 	struct bt_mesh_scene_srv *srv =
// 		CONTAINER_OF(k_work_delayable_from_work(work), struct bt_mesh_scene_srv, work);

// 	if (srv->next == BT_MESH_SCENE_NONE) {
// 		/* This is already done */
// 		return;
// 	}

// 	srv->prev = srv->next;
// 	srv->next = BT_MESH_SCENE_NONE;

// 	/* Publish at the end of the transition */
// 	if (bt_mesh_model_transition_time(&srv->transition)) {
// 		bt_mesh_scene_srv_pub(srv, NULL);
// 	}
// }

static int scene_srv_pub_update(struct bt_mesh_model *model)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;
    struct bt_mesh_scene_state state;

    curr_scene_state_get(srv, &state);
    scene_status_encode(srv, &srv->pub_msg, &state);
    return 0;
}

static int scene_srv_init(struct bt_mesh_model *model)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;

    sys_slist_prepend(&scene_servers, &srv->n);

    srv->model = model;

    // k_work_init_delayable(&srv->work, scene_srv_transition_end);

    net_buf_simple_init_with_data(&srv->pub_msg, srv->buf,
                                  sizeof(srv->buf));
    srv->pub.msg = &srv->pub_msg;
    srv->pub.update = scene_srv_pub_update;
    return 0;
}

static int scene_srv_set(struct bt_mesh_model *model, const char *path,
                         size_t len_rd, settings_read_cb read_cb, void *cb_arg)
{
#if 0 // not adapter
    struct bt_mesh_scene_srv *srv = model->rt->user_data;
    uint8_t buf[SCENE_PAGE_SIZE];
    uint16_t scene;
    ssize_t size;
    uint8_t page;
    bool vnd;

    log_debug("path: %s", path);

    /* The entire model data tree is loaded in this callback. Depending on
     * the path and whether we have started the mesh, we'll handle the data
     * differently:
     *
     * - Path "XXXX/vYY": Scene XXXX vendor model page YY
     * - Path "XXXX/sYY": Scene XXXX sig model page YY
     */
    scene = strtol(path, NULL, 16);
    if (scene == BT_MESH_SCENE_NONE) {
        log_error("Unknown data %s", path);
        return 0;
    }

    settings_name_next(path, &path);
    if (!path) {
        return 0;
    }

    vnd = path[0] == 'v';
    page = strtol(&path[1], NULL, 16);
    update_page_count(srv, vnd, page);

    /* Before starting the mesh, we'll just register that the scene exists:
     * Once the mesh starts, we'll load the current scene, and end up in
     * this callback again, but bt_mesh_is_provisioned() will be true.
     */
    if (!bt_mesh_is_provisioned()) {
        if (scene_find(srv, scene)) {
            return 0;
        }

        if (srv->count == ARRAY_SIZE(srv->all)) {
            log_error("No room for scene 0x%x", scene);
            return 0;
        }

        log_debug("Recovered scene 0x%x", scene);
        srv->all[srv->count++] = scene;
        return 0;
    }

    size = read_cb(cb_arg, &buf, sizeof(buf));
    if (size < 0) {
        log_error("Failed loading scene 0x%x", scene);
        return -EINVAL;
    }

    log_debug("0x%x: %s", scene, bt_hex(buf, size));
    page_recover(srv, vnd, buf, size);
#endif
    return 0;
}

static void scene_srv_reset(struct bt_mesh_model *model)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;

    srv->next = BT_MESH_SCENE_NONE;

    while (srv->count) {
        scene_delete(srv, &srv->all[0]);
    }

    srv->prev = BT_MESH_SCENE_NONE;
    /* We're checking srv->next in the handler, so failure to cancel is okay: */
    (void)k_work_cancel_delayable(&srv->work);
    srv->sigpages = 0;
    srv->vndpages = 0;
}

const struct bt_mesh_model_cb _bt_mesh_scene_srv_cb = {
    .init = scene_srv_init,
    .settings_set = scene_srv_set,
    .reset = scene_srv_reset,
};

static int scene_setup_srv_init(struct bt_mesh_model *model)
{
    struct bt_mesh_scene_srv *srv = model->rt->user_data;
    struct bt_mesh_dtt_srv *dtt_srv = NULL;
    int err;

    if (!srv) {
        return -EINVAL;
    }

    srv->setup_mod = model;
    //for compiler, not used now.
    // if (IS_ENABLED(CONFIG_BT_MESH_DTT_SRV)) {
    // 	dtt_srv = bt_mesh_dtt_srv_get(bt_mesh_model_elem(model));
    // }

    // if (!dtt_srv) {
    // 	log_error("Failed to find Generic DTT Server on element");
    // 	return -EINVAL;
    // }

    // err = bt_mesh_model_extend(srv->setup_mod, dtt_srv->model);
    // if (err) {
    // 	return err;
    // }
    //for compiler, not used now.

#if CONFIG_BT_MESH_COMP_PAGE_1
    err = bt_mesh_model_correspond(srv->setup_mod, srv->model);
    if (err) {
        return err;
    }
#endif

#if CONFIG_BT_MESH_MODEL_EXTENSIONS
    return bt_mesh_model_extend(srv->setup_mod, srv->model);
#else
    return 0;
#endif
}

const struct bt_mesh_model_cb _bt_mesh_scene_setup_srv_cb = {
    .init = scene_setup_srv_init,
};

void bt_mesh_scene_invalidate(struct bt_mesh_model *mod)
{
    struct bt_mesh_scene_srv *srv = srv_find(mod->rt->elem_idx);

    if (!srv) {
        return;
    }

    srv->prev = BT_MESH_SCENE_NONE;
    /* We're checking srv->next in the handler, so failure to cancel is okay: */
    (void)k_work_cancel_delayable(&srv->work);
    srv->next = BT_MESH_SCENE_NONE;
}

int bt_mesh_scene_srv_set(struct bt_mesh_scene_srv *srv, uint16_t scene,
                          struct bt_mesh_model_transition *transition)
{
    int32_t transition_time;
    uint16_t curr;
    char path[25];
    int err;

    if (scene == BT_MESH_SCENE_NONE ||
        model_transition_is_invalid(transition)) {
        return -EINVAL;
    }

    if (!scene_find(srv, scene)) {
        log_error("Unknown scene 0x%x", scene);
        return -ENOENT;
    }

    curr = current_scene(srv);
    if (scene == curr) {
        srv->prev = scene;
        srv->next = BT_MESH_SCENE_NONE;
        srv->transition.time = 0;
        srv->transition.delay = 0;
        /* We're checking srv->next in the handler, so failure to cancel is okay: */
        (void)k_work_cancel_delayable(&srv->work);
        return 0;
    }

    transition_time = bt_mesh_model_transition_time(transition);
    if (transition_time) {
        srv->transition = *transition;
        srv->prev = curr;
        srv->next = scene;
        k_work_reschedule(&srv->work, K_MSEC(transition_time));
    } else {
        srv->prev = scene;
        srv->next = BT_MESH_SCENE_NONE;
        srv->transition.time = 0;
        srv->transition.delay = 0;
        /* We're checking srv->next in the handler, so failure to cancel is okay: */
        (void)k_work_cancel_delayable(&srv->work);
    }

    sprintf(path, "bt/mesh/s/%x/data/%x",
            (srv->model->rt->elem_idx << 8) | srv->model->rt->mod_idx, scene);

    log_debug("Loading %s", path);

    //for compiler, not used now.
    // err = settings_load_subtree(path);
    // if (!err) {
    // 	scene_recall_complete(srv);
    // }

    return err;
}

int bt_mesh_scene_srv_pub(struct bt_mesh_scene_srv *srv,
                          struct bt_mesh_msg_ctx *ctx)
{
    struct bt_mesh_scene_state state;

    curr_scene_state_get(srv, &state);
    return scene_status_send(srv->model, ctx, &state);
}

uint16_t bt_mesh_scene_srv_current_scene_get(const struct bt_mesh_scene_srv *srv)
{
    return current_scene(srv);
}

uint16_t bt_mesh_scene_srv_target_scene_get(const struct bt_mesh_scene_srv *srv)
{
    return target_scene(srv);
}

#endif /* CONFIG_BT_MESH_SCENE_SRV */