/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @file camera_control_service.c
 * @brief Apache Axis2/C HTTP/2 Generic Camera Control Service Implementation
 *
 * Generic camera control service using json-c library (no XML/SOAP dependencies).
 * Provides stub implementations for common camera operations that users can
 * customize for their specific camera systems.
 *
 * This service follows the same patterns as BigDataH2Service, LoginService, and
 * TestwsService to provide a consistent 4th user guide service example.
 *
 * Features:
 * - HTTP/2 transport optimization
 * - Pure JSON processing (no axiom/XML)
 * - Generic camera operation interface
 * - User-implementable stub functions
 * - Comprehensive error handling
 * - Input validation and sanitization
 *
 * CRITICAL IMPLEMENTATION NOTE:
 * This service contains ONLY stub implementations. All camera-specific code
 * has been left as stubs with detailed comments for user implementation.
 * This ensures no GPL or other licensed code contaminates the Apache codebase.
 *
 * Users must implement the camera_device_*_impl() functions for their specific
 * camera system. See implementation guide for integration examples.
 */

#include "camera_control_service.h"
#include <axutil_string.h>
#include <axutil_utils.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>

/* Internal utility functions */
static json_object* create_error_response(const axutil_env_t *env,
                                         const axis2_char_t *error_message);
static json_object* create_success_response(const axutil_env_t *env,
                                           const axis2_char_t *message);
static axis2_bool_t is_valid_clip_name(const axis2_char_t *clip_name);
static axis2_bool_t is_valid_quality(const axis2_char_t *quality);

/**
 * Create Camera Recording Parameters from JSON string using pure json-c
 */
AXIS2_EXTERN camera_recording_params_t* AXIS2_CALL
camera_recording_params_create_from_json(
    const axutil_env_t *env,
    const axis2_char_t *json_string)
{
    camera_recording_params_t *params = NULL;
    json_object *json_obj = NULL;
    json_object *value_obj = NULL;

    if (!env || !json_string)
    {
        AXIS2_ERROR_SET(env->error, AXIS2_ERROR_INVALID_NULL_PARAM, AXIS2_FAILURE);
        return NULL;
    }

    /* Parse JSON using json-c */
    json_obj = json_tokener_parse(json_string);
    if (!json_obj)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI, "Failed to parse JSON camera request");
        return NULL;
    }

    params = AXIS2_MALLOC(env->allocator, sizeof(camera_recording_params_t));
    if (!params)
    {
        json_object_put(json_obj);
        return NULL;
    }
    memset(params, 0, sizeof(camera_recording_params_t));

    /* Extract clip_name */
    if (json_object_object_get_ex(json_obj, "clip_name", &value_obj))
    {
        const char *clip_name = json_object_get_string(value_obj);
        if (clip_name)
        {
            params->clip_name = camera_service_sanitize_input(env, clip_name,
                                                             CAMERA_CLIP_NAME_MAX_LENGTH);
        }
    }

    /* Extract quality */
    if (json_object_object_get_ex(json_obj, "quality", &value_obj))
    {
        const char *quality = json_object_get_string(value_obj);
        if (quality)
        {
            params->quality = camera_service_sanitize_input(env, quality,
                                                           CAMERA_QUALITY_MAX_LENGTH);
        }
    }

    /* Extract duration */
    if (json_object_object_get_ex(json_obj, "duration", &value_obj))
    {
        params->duration = json_object_get_int(value_obj);
    }

    /* Extract format */
    if (json_object_object_get_ex(json_obj, "format", &value_obj))
    {
        const char *format = json_object_get_string(value_obj);
        if (format)
        {
            params->format = camera_service_sanitize_input(env, format,
                                                          CAMERA_QUALITY_MAX_LENGTH);
        }
    }

    json_object_put(json_obj);
    return params;
}

/**
 * Create Camera Settings from JSON string using pure json-c
 */
AXIS2_EXTERN camera_settings_t* AXIS2_CALL
camera_settings_create_from_json(
    const axutil_env_t *env,
    const axis2_char_t *json_string)
{
    camera_settings_t *settings = NULL;
    json_object *json_obj = NULL;
    json_object *value_obj = NULL;

    if (!env || !json_string)
    {
        AXIS2_ERROR_SET(env->error, AXIS2_ERROR_INVALID_NULL_PARAM, AXIS2_FAILURE);
        return NULL;
    }

    json_obj = json_tokener_parse(json_string);
    if (!json_obj)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI, "Failed to parse JSON camera settings");
        return NULL;
    }

    settings = AXIS2_MALLOC(env->allocator, sizeof(camera_settings_t));
    if (!settings)
    {
        json_object_put(json_obj);
        return NULL;
    }
    memset(settings, 0, sizeof(camera_settings_t));

    /* Extract resolution */
    if (json_object_object_get_ex(json_obj, "resolution", &value_obj))
    {
        const char *resolution = json_object_get_string(value_obj);
        if (resolution)
        {
            settings->resolution = camera_service_sanitize_input(env, resolution,
                                                                CAMERA_QUALITY_MAX_LENGTH);
        }
    }

    /* Extract fps */
    if (json_object_object_get_ex(json_obj, "fps", &value_obj))
    {
        const char *fps = json_object_get_string(value_obj);
        if (fps)
        {
            settings->fps = camera_service_sanitize_input(env, fps,
                                                         CAMERA_QUALITY_MAX_LENGTH);
        }
    }

    /* Extract codec */
    if (json_object_object_get_ex(json_obj, "codec", &value_obj))
    {
        const char *codec = json_object_get_string(value_obj);
        if (codec)
        {
            settings->codec = camera_service_sanitize_input(env, codec,
                                                           CAMERA_QUALITY_MAX_LENGTH);
        }
    }

    /* Extract bitrate */
    if (json_object_object_get_ex(json_obj, "bitrate", &value_obj))
    {
        const char *bitrate = json_object_get_string(value_obj);
        if (bitrate)
        {
            settings->bitrate = camera_service_sanitize_input(env, bitrate,
                                                             CAMERA_QUALITY_MAX_LENGTH);
        }
    }

    /* Extract audio_source */
    if (json_object_object_get_ex(json_obj, "audio_source", &value_obj))
    {
        const char *audio_source = json_object_get_string(value_obj);
        if (audio_source)
        {
            settings->audio_source = camera_service_sanitize_input(env, audio_source,
                                                                  CAMERA_QUALITY_MAX_LENGTH);
        }
    }

    json_object_put(json_obj);
    return settings;
}

/**
 * Free camera recording parameters
 */
AXIS2_EXTERN void AXIS2_CALL
camera_recording_params_free(camera_recording_params_t *params,
                            const axutil_env_t *env)
{
    if (!params || !env)
        return;

    if (params->clip_name)
        AXIS2_FREE(env->allocator, params->clip_name);
    if (params->quality)
        AXIS2_FREE(env->allocator, params->quality);
    if (params->format)
        AXIS2_FREE(env->allocator, params->format);

    AXIS2_FREE(env->allocator, params);
}

/**
 * Free camera settings
 */
AXIS2_EXTERN void AXIS2_CALL
camera_settings_free(camera_settings_t *settings,
                    const axutil_env_t *env)
{
    if (!settings || !env)
        return;

    if (settings->resolution)
        AXIS2_FREE(env->allocator, settings->resolution);
    if (settings->fps)
        AXIS2_FREE(env->allocator, settings->fps);
    if (settings->codec)
        AXIS2_FREE(env->allocator, settings->codec);
    if (settings->bitrate)
        AXIS2_FREE(env->allocator, settings->bitrate);
    if (settings->audio_source)
        AXIS2_FREE(env->allocator, settings->audio_source);

    AXIS2_FREE(env->allocator, settings);
}

/**
 * Free camera status
 */
AXIS2_EXTERN void AXIS2_CALL
camera_status_free(camera_status_t *status,
                  const axutil_env_t *env)
{
    if (!status || !env)
        return;

    if (status->state)
        AXIS2_FREE(env->allocator, status->state);
    if (status->active_clip)
        AXIS2_FREE(env->allocator, status->active_clip);
    if (status->last_error)
        AXIS2_FREE(env->allocator, status->last_error);

    AXIS2_FREE(env->allocator, status);
}

/**
 * Create SFTP Transfer Parameters from JSON string using pure json-c
 */
AXIS2_EXTERN sftp_transfer_params_t* AXIS2_CALL
sftp_transfer_params_create_from_json(
    const axutil_env_t *env,
    const axis2_char_t *json_string)
{
    sftp_transfer_params_t *params = NULL;
    json_object *json_obj = NULL;
    json_object *value_obj = NULL;

    if (!env || !json_string)
    {
        AXIS2_ERROR_SET(env->error, AXIS2_ERROR_INVALID_NULL_PARAM, AXIS2_FAILURE);
        return NULL;
    }

    json_obj = json_tokener_parse(json_string);
    if (!json_obj)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI, "Failed to parse JSON SFTP transfer request");
        return NULL;
    }

    params = AXIS2_MALLOC(env->allocator, sizeof(sftp_transfer_params_t));
    if (!params)
    {
        json_object_put(json_obj);
        return NULL;
    }
    memset(params, 0, sizeof(sftp_transfer_params_t));

    /* Extract hostname */
    if (json_object_object_get_ex(json_obj, "hostname", &value_obj))
    {
        const char *hostname = json_object_get_string(value_obj);
        if (hostname)
        {
            params->hostname = camera_service_sanitize_input(env, hostname,
                                                            CAMERA_HOSTNAME_MAX_LENGTH);
        }
    }

    /* Extract username */
    if (json_object_object_get_ex(json_obj, "username", &value_obj))
    {
        const char *username = json_object_get_string(value_obj);
        if (username)
        {
            params->username = camera_service_sanitize_input(env, username,
                                                            CAMERA_USERNAME_MAX_LENGTH);
        }
    }

    /* Extract private_key_path */
    if (json_object_object_get_ex(json_obj, "private_key_path", &value_obj))
    {
        const char *private_key_path = json_object_get_string(value_obj);
        if (private_key_path)
        {
            params->private_key_path = camera_service_sanitize_input(env, private_key_path,
                                                                    CAMERA_PATH_MAX_LENGTH);
        }
    }

    /* Extract remote_path */
    if (json_object_object_get_ex(json_obj, "remote_path", &value_obj))
    {
        const char *remote_path = json_object_get_string(value_obj);
        if (remote_path)
        {
            params->remote_path = camera_service_sanitize_input(env, remote_path,
                                                               CAMERA_PATH_MAX_LENGTH);
        }
    }

    /* Extract local_file_path */
    if (json_object_object_get_ex(json_obj, "local_file_path", &value_obj))
    {
        const char *local_file_path = json_object_get_string(value_obj);
        if (local_file_path)
        {
            params->local_file_path = camera_service_sanitize_input(env, local_file_path,
                                                                   CAMERA_PATH_MAX_LENGTH);
        }
    }

    /* Extract port */
    if (json_object_object_get_ex(json_obj, "port", &value_obj))
    {
        params->port = json_object_get_int(value_obj);
    }
    else
    {
        params->port = 22;  /* Default SSH port */
    }

    json_object_put(json_obj);
    return params;
}

/**
 * Free SFTP transfer parameters
 */
AXIS2_EXTERN void AXIS2_CALL
sftp_transfer_params_free(sftp_transfer_params_t *params,
                         const axutil_env_t *env)
{
    if (!params || !env)
        return;

    if (params->hostname)
        AXIS2_FREE(env->allocator, params->hostname);
    if (params->username)
        AXIS2_FREE(env->allocator, params->username);
    if (params->private_key_path)
        AXIS2_FREE(env->allocator, params->private_key_path);
    if (params->remote_path)
        AXIS2_FREE(env->allocator, params->remote_path);
    if (params->local_file_path)
        AXIS2_FREE(env->allocator, params->local_file_path);

    AXIS2_FREE(env->allocator, params);
}

/**
 * Create File List Parameters from JSON string using pure json-c
 */
AXIS2_EXTERN file_list_params_t* AXIS2_CALL
file_list_params_create_from_json(
    const axutil_env_t *env,
    const axis2_char_t *json_string)
{
    file_list_params_t *params = NULL;
    json_object *json_obj = NULL;
    json_object *value_obj = NULL;

    if (!env || !json_string)
    {
        AXIS2_ERROR_SET(env->error, AXIS2_ERROR_INVALID_NULL_PARAM, AXIS2_FAILURE);
        return NULL;
    }

    json_obj = json_tokener_parse(json_string);
    if (!json_obj)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI, "Failed to parse JSON file list request");
        return NULL;
    }

    params = AXIS2_MALLOC(env->allocator, sizeof(file_list_params_t));
    if (!params)
    {
        json_object_put(json_obj);
        return NULL;
    }
    memset(params, 0, sizeof(file_list_params_t));

    /* Extract pattern (optional) */
    if (json_object_object_get_ex(json_obj, "pattern", &value_obj))
    {
        const char *pattern = json_object_get_string(value_obj);
        if (pattern)
        {
            params->pattern = camera_service_sanitize_input(env, pattern,
                                                           CAMERA_PATH_MAX_LENGTH);
        }
    }

    /* Extract directory (optional) */
    if (json_object_object_get_ex(json_obj, "directory", &value_obj))
    {
        const char *directory = json_object_get_string(value_obj);
        if (directory)
        {
            params->directory = camera_service_sanitize_input(env, directory,
                                                             CAMERA_PATH_MAX_LENGTH);
        }
    }

    json_object_put(json_obj);
    return params;
}

/**
 * Free file list parameters
 */
AXIS2_EXTERN void AXIS2_CALL
file_list_params_free(file_list_params_t *params,
                      const axutil_env_t *env)
{
    if (!params || !env)
        return;

    if (params->pattern)
        AXIS2_FREE(env->allocator, params->pattern);
    if (params->directory)
        AXIS2_FREE(env->allocator, params->directory);

    AXIS2_FREE(env->allocator, params);
}

/**
 * Free file list result
 */
AXIS2_EXTERN void AXIS2_CALL
file_list_result_free(file_list_result_t *result,
                      const axutil_env_t *env)
{
    if (!result || !env)
        return;

    if (result->files)
    {
        for (int i = 0; i < result->file_count; i++)
        {
            if (result->files[i].name)
                AXIS2_FREE(env->allocator, result->files[i].name);
            if (result->files[i].modified)
                AXIS2_FREE(env->allocator, result->files[i].modified);
        }
        AXIS2_FREE(env->allocator, result->files);
    }

    if (result->directory)
        AXIS2_FREE(env->allocator, result->directory);

    AXIS2_FREE(env->allocator, result);
}

/**
 * Create File Delete Parameters from JSON string using pure json-c
 */
AXIS2_EXTERN file_delete_params_t* AXIS2_CALL
file_delete_params_create_from_json(
    const axutil_env_t *env,
    const axis2_char_t *json_string)
{
    file_delete_params_t *params = NULL;
    json_object *json_obj = NULL;
    json_object *value_obj = NULL;

    if (!env || !json_string)
    {
        AXIS2_ERROR_SET(env->error, AXIS2_ERROR_INVALID_NULL_PARAM, AXIS2_FAILURE);
        return NULL;
    }

    json_obj = json_tokener_parse(json_string);
    if (!json_obj)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI, "Failed to parse JSON file delete request");
        return NULL;
    }

    params = AXIS2_MALLOC(env->allocator, sizeof(file_delete_params_t));
    if (!params)
    {
        json_object_put(json_obj);
        return NULL;
    }
    memset(params, 0, sizeof(file_delete_params_t));

    /* Extract pattern (required) */
    if (json_object_object_get_ex(json_obj, "pattern", &value_obj))
    {
        const char *pattern = json_object_get_string(value_obj);
        if (pattern)
        {
            params->pattern = camera_service_sanitize_input(env, pattern,
                                                           CAMERA_PATH_MAX_LENGTH);
        }
    }

    json_object_put(json_obj);
    return params;
}

/**
 * Free file delete parameters
 */
AXIS2_EXTERN void AXIS2_CALL
file_delete_params_free(file_delete_params_t *params,
                        const axutil_env_t *env)
{
    if (!params || !env)
        return;

    if (params->pattern)
        AXIS2_FREE(env->allocator, params->pattern);

    AXIS2_FREE(env->allocator, params);
}

/* ========================================================================
 * STUB IMPLEMENTATIONS - USERS MUST REPLACE WITH CAMERA-SPECIFIC CODE
 * ========================================================================
 *
 * The following functions are STUB implementations only. They provide
 * basic functionality for testing and demonstration purposes, but users
 * must replace them with camera-specific integration code.
 *
 * See the implementation guide for examples of integrating with:
 * - OpenCamera (Android JNI bridge)
 * - V4L2 (Linux Video4Linux2)
 * - IP cameras (RTSP/HTTP control)
 * - Custom camera hardware
 */

/**
 * STUB: Start camera recording implementation
 *
 * IMPLEMENTATION REQUIRED: Users must replace this stub with camera-specific code.
 *
 * Example integration approaches:
 *
 * 1. OpenCamera JNI Integration (requires GPL v3+ fork or external implementation):
 *    ```c
 *    JNIEnv *jni_env = get_jni_env();
 *    jclass camera_class = (*jni_env)->FindClass(jni_env,
 *        "net/sourceforge/opencamera/MainActivity");
 *    jmethodID start_method = (*jni_env)->GetMethodID(jni_env, camera_class,
 *        "startVideoRecording", "(Ljava/lang/String;Ljava/lang/String;)V");
 *    jstring j_clip_name = (*jni_env)->NewStringUTF(jni_env, params->clip_name);
 *    jstring j_quality = (*jni_env)->NewStringUTF(jni_env, params->quality);
 *    (*jni_env)->CallVoidMethod(jni_env, get_main_activity_instance(),
 *                               start_method, j_clip_name, j_quality);
 *    ```
 *
 * 2. V4L2 Integration:
 *    ```c
 *    int fd = open("/dev/video0", O_RDWR);
 *    struct v4l2_format fmt;
 *    // Configure capture format based on params->quality
 *    // Start capture and encoding pipeline
 *    // Save to params->clip_name
 *    ```
 *
 * 3. IP Camera Integration:
 *    ```c
 *    // Send HTTP/RTSP command to start recording
 *    char cmd[512];
 *    snprintf(cmd, sizeof(cmd),
 *        "curl -X POST http://camera-ip/api/record -d '{\"filename\":\"%s\",\"quality\":\"%s\"}'",
 *        params->clip_name, params->quality);
 *    system(cmd);
 *    ```
 */
AXIS2_EXTERN axis2_status_t AXIS2_CALL
camera_device_start_recording_impl(
    const axutil_env_t *env,
    const camera_recording_params_t *params)
{
    /* STUB IMPLEMENTATION - USER MUST REPLACE */

    if (!env || !params)
    {
        return AXIS2_FAILURE;
    }

    /* Basic parameter validation */
    if (!params->clip_name || strlen(params->clip_name) == 0)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI,
            "STUB: Invalid clip_name for recording");
        return AXIS2_FAILURE;
    }

    /* Log the stub operation */
    AXIS2_LOG_INFO(env->log,
        "STUB: Start recording request - clipName: %s, quality: %s, duration: %d, format: %s",
        params->clip_name ? params->clip_name : "default",
        params->quality ? params->quality : "1080p",
        params->duration,
        params->format ? params->format : "mp4");

    AXIS2_LOG_WARNING(env->log, AXIS2_LOG_SI,
        "STUB: camera_device_start_recording_impl() - Replace with camera-specific implementation!");
    AXIS2_LOG_INFO(env->log,
        "STUB: See camera_control_service.c for integration examples (OpenCamera JNI, V4L2, IP cameras)");

    /*
     * USER IMPLEMENTATION GOES HERE
     * Replace this entire function with camera-specific code
     */

    return AXIS2_SUCCESS; /* Stub always succeeds for testing */
}

/**
 * STUB: Stop camera recording implementation
 *
 * IMPLEMENTATION REQUIRED: Users must replace this stub with camera-specific code.
 *
 * Example implementations:
 *
 * 1. OpenCamera JNI Integration:
 *    Call Java methods to stop recording
 *
 * 2. V4L2 Integration:
 *    Stop capture device and close file descriptors
 *
 * 3. IP Camera Integration:
 *    Send stop recording command to camera API
 */
AXIS2_EXTERN axis2_status_t AXIS2_CALL
camera_device_stop_recording_impl(const axutil_env_t *env)
{
    /* STUB IMPLEMENTATION - USER MUST REPLACE */

    if (!env)
    {
        return AXIS2_FAILURE;
    }

    /* Log the stub operation */
    AXIS2_LOG_INFO(env->log, "STUB: Stop recording request");

    AXIS2_LOG_WARNING(env->log, AXIS2_LOG_SI,
        "STUB: camera_device_stop_recording_impl() - Replace with camera-specific implementation!");

    /*
     * USER IMPLEMENTATION GOES HERE
     * Replace this entire function with camera-specific code
     */

    return AXIS2_SUCCESS; /* Stub always succeeds for testing */
}

/**
 * STUB: Get camera status implementation
 *
 * IMPLEMENTATION REQUIRED: Users must replace this stub with camera-specific code.
 */
AXIS2_EXTERN camera_status_t* AXIS2_CALL
camera_device_get_status_impl(const axutil_env_t *env)
{
    /* STUB IMPLEMENTATION - USER MUST REPLACE */

    camera_status_t *status = NULL;

    if (!env)
    {
        return NULL;
    }

    status = AXIS2_MALLOC(env->allocator, sizeof(camera_status_t));
    if (!status)
    {
        return NULL;
    }
    memset(status, 0, sizeof(camera_status_t));

    /* Create stub status response */
    status->state = axutil_strdup(env, "idle");
    status->active_clip = axutil_strdup(env, "none");
    status->recording_duration = 0;
    status->last_error = axutil_strdup(env, "none");

    AXIS2_LOG_INFO(env->log, "STUB: Get status request");
    AXIS2_LOG_WARNING(env->log, AXIS2_LOG_SI,
        "This is a stub function; user needs to implement the code for their use case");

    /* Print message to standard output as well */
    printf("This is a stub function; user needs to implement the code for their use case\n");

    /*
     * USER IMPLEMENTATION GOES HERE
     * Query actual camera device and return real status
     */

    return status;
}

/**
 * STUB: Configure camera settings implementation
 *
 * IMPLEMENTATION REQUIRED: Users must replace this stub with camera-specific code.
 */
AXIS2_EXTERN axis2_status_t AXIS2_CALL
camera_device_configure_settings_impl(
    const axutil_env_t *env,
    const camera_settings_t *settings)
{
    /* STUB IMPLEMENTATION - USER MUST REPLACE */

    if (!env || !settings)
    {
        return AXIS2_FAILURE;
    }

    /* Log the stub operation */
    AXIS2_LOG_INFO(env->log,
        "STUB: Configure settings - resolution: %s, fps: %s, codec: %s, bitrate: %s, audio: %s",
        settings->resolution ? settings->resolution : "default",
        settings->fps ? settings->fps : "30",
        settings->codec ? settings->codec : "h264",
        settings->bitrate ? settings->bitrate : "auto",
        settings->audio_source ? settings->audio_source : "mic");

    AXIS2_LOG_WARNING(env->log, AXIS2_LOG_SI,
        "STUB: camera_device_configure_settings_impl() - Replace with camera-specific implementation!");

    /*
     * USER IMPLEMENTATION GOES HERE
     * Apply settings to actual camera device
     */

    return AXIS2_SUCCESS; /* Stub always succeeds for testing */
}

/**
 * STUB: SFTP file transfer with PKI authentication implementation
 *
 * IMPLEMENTATION REQUIRED: Users must replace this stub with SFTP client code.
 *
 * Example integration approaches:
 *
 * 1. libssh2 Integration (recommended for C applications):
 *    ```c
 *    LIBSSH2_SESSION *session = libssh2_session_init();
 *    libssh2_session_handshake(session, sock);
 *    libssh2_userauth_publickey_fromfile(session, params->username,
 *        NULL, params->private_key_path, NULL);
 *    LIBSSH2_SFTP *sftp_session = libssh2_sftp_init(session);
 *    LIBSSH2_SFTP_HANDLE *sftp_handle = libssh2_sftp_open(sftp_session,
 *        remote_file_path, LIBSSH2_FXF_WRITE|LIBSSH2_FXF_CREAT,
 *        LIBSSH2_SFTP_S_IRUSR|LIBSSH2_SFTP_S_IWUSR);
 *    // Transfer file data
 *    ```
 *
 * 2. System sftp command (simpler but less control):
 *    ```c
 *    char sftp_cmd[1024];
 *    snprintf(sftp_cmd, sizeof(sftp_cmd),
 *        "sftp -o PasswordAuthentication=no -o StrictHostKeyChecking=no "
 *        "-i %s -P %d %s@%s:%s <<< 'put %s'",
 *        params->private_key_path, params->port, params->username,
 *        params->hostname, params->remote_path, params->local_file_path);
 *    int result = system(sftp_cmd);
 *    ```
 *
 * 3. SSH with scp (alternative file transfer):
 *    ```c
 *    char scp_cmd[1024];
 *    snprintf(scp_cmd, sizeof(scp_cmd),
 *        "scp -o PasswordAuthentication=no -i %s -P %d %s %s@%s:%s",
 *        params->private_key_path, params->port, params->local_file_path,
 *        params->username, params->hostname, params->remote_path);
 *    int result = system(scp_cmd);
 *    ```
 */
AXIS2_EXTERN axis2_status_t AXIS2_CALL
camera_device_sftp_transfer_impl(
    const axutil_env_t *env,
    const sftp_transfer_params_t *params)
{
    /* STUB IMPLEMENTATION - USER MUST REPLACE */

    if (!env || !params)
    {
        return AXIS2_FAILURE;
    }

    /* Basic parameter validation */
    if (!params->hostname || strlen(params->hostname) == 0)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI,
            "STUB: Invalid hostname for SFTP transfer");
        return AXIS2_FAILURE;
    }

    if (!params->username || strlen(params->username) == 0)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI,
            "STUB: Invalid username for SFTP transfer");
        return AXIS2_FAILURE;
    }

    if (!params->local_file_path || strlen(params->local_file_path) == 0)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI,
            "STUB: Invalid local file path for SFTP transfer");
        return AXIS2_FAILURE;
    }

    if (!params->private_key_path || strlen(params->private_key_path) == 0)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI,
            "STUB: Invalid private key path for SFTP transfer");
        return AXIS2_FAILURE;
    }

    /* Log the stub operation */
    AXIS2_LOG_INFO(env->log,
        "STUB: SFTP transfer request - file: %s, host: %s@%s:%d, remote_path: %s, key: %s",
        params->local_file_path ? params->local_file_path : "unknown",
        params->username ? params->username : "unknown",
        params->hostname ? params->hostname : "unknown",
        params->port,
        params->remote_path ? params->remote_path : "/",
        params->private_key_path ? params->private_key_path : "unknown");

    AXIS2_LOG_WARNING(env->log, AXIS2_LOG_SI,
        "STUB: camera_device_sftp_transfer_impl() - Replace with SFTP client implementation!");
    AXIS2_LOG_INFO(env->log,
        "STUB: See camera_control_service.c for integration examples (libssh2, system sftp, scp)");

    /*
     * USER IMPLEMENTATION GOES HERE
     * Replace this entire function with SFTP client code
     *
     * Recommended approach:
     * 1. Check if private key file exists and is readable
     * 2. Check if local file to transfer exists
     * 3. Establish SSH connection to remote host
     * 4. Authenticate using private key (PKI - no password)
     * 5. Initialize SFTP session
     * 6. Transfer file to remote path
     * 7. Verify transfer completed successfully
     * 8. Clean up connections and return status
     */

    return AXIS2_SUCCESS; /* Stub always succeeds for testing */
}

/**
 * STUB: List video files on device implementation
 *
 * IMPLEMENTATION REQUIRED: Users must replace this stub with storage-specific code.
 *
 * Example implementations (reference: Kanaha camera app):
 *
 * 1. Android Integration via Intent IPC:
 *    ```c
 *    // Send broadcast to Java receiver
 *    char intent_command[1024];
 *    snprintf(intent_command, sizeof(intent_command),
 *        "am broadcast --user 0 "
 *        "-n org.myapp/org.myapp.CameraReceiver "
 *        "-a org.myapp.CAMERA_CONTROL "
 *        "--es action list_files "
 *        "--es pattern '%s'",
 *        params->pattern ? params->pattern : "");
 *    system(intent_command);
 *    // Read response from file written by Java receiver
 *    ```
 *
 * 2. Linux filesystem integration:
 *    ```c
 *    DIR *dir = opendir("/var/camera/videos");
 *    struct dirent *entry;
 *    struct stat st;
 *    while ((entry = readdir(dir)) != NULL) {
 *        if (fnmatch(params->pattern ? params->pattern : "*.mp4",
 *                    entry->d_name, 0) == 0) {
 *            stat(entry->d_name, &st);
 *            // Add to result list
 *        }
 *    }
 *    closedir(dir);
 *    ```
 */
AXIS2_EXTERN file_list_result_t* AXIS2_CALL
camera_device_list_files_impl(
    const axutil_env_t *env,
    const file_list_params_t *params)
{
    /* STUB IMPLEMENTATION - USER MUST REPLACE */

    file_list_result_t *result = NULL;

    if (!env)
    {
        return NULL;
    }

    result = AXIS2_MALLOC(env->allocator, sizeof(file_list_result_t));
    if (!result)
    {
        return NULL;
    }
    memset(result, 0, sizeof(file_list_result_t));

    /* Log the stub operation */
    AXIS2_LOG_INFO(env->log,
        "STUB: List files request - pattern: %s, directory: %s",
        params && params->pattern ? params->pattern : "*",
        params && params->directory ? params->directory : "default");

    AXIS2_LOG_WARNING(env->log, AXIS2_LOG_SI,
        "STUB: camera_device_list_files_impl() - Replace with storage-specific implementation!");

    /* Create stub result - empty file list */
    result->file_count = 0;
    result->total_size = 0;
    result->files = NULL;
    result->directory = axutil_strdup(env, "/storage/emulated/0/DCIM/OpenCamera");

    /*
     * USER IMPLEMENTATION GOES HERE
     * Replace this entire function with storage-specific code to list video files
     *
     * Expected behavior:
     * 1. Determine target directory (use params->directory or default video storage)
     * 2. List files matching params->pattern (or all video files if NULL)
     * 3. For each file, populate file_info_t with name, size, modified timestamp
     * 4. Return file_list_result_t with file_count, total_size, and files array
     */

    return result;
}

/**
 * STUB: Delete video files from device implementation
 *
 * IMPLEMENTATION REQUIRED: Users must replace this stub with storage-specific code.
 *
 * Pattern support (reference: Kanaha implementation):
 *   - Specific file: "VID_20260104_105049.mp4"
 *   - Wildcard: "*.mp4", "VID_2026*"
 *   - Date: "2026-01-04" (all files from that date)
 *   - Today: "today" (all files from current date)
 *   - All: "*" (delete all video files)
 *
 * Example implementations:
 *
 * 1. Android Integration via Intent IPC:
 *    ```c
 *    char intent_command[1024];
 *    snprintf(intent_command, sizeof(intent_command),
 *        "am broadcast --user 0 "
 *        "-n org.myapp/org.myapp.CameraReceiver "
 *        "-a org.myapp.CAMERA_CONTROL "
 *        "--es action delete_files "
 *        "--es pattern '%s'",
 *        params->pattern);
 *    system(intent_command);
 *    ```
 *
 * 2. Linux filesystem integration:
 *    ```c
 *    // Security: Validate pattern doesn't contain ".."
 *    if (strstr(params->pattern, "..")) return AXIS2_FAILURE;
 *
 *    glob_t globbuf;
 *    char path_pattern[512];
 *    snprintf(path_pattern, sizeof(path_pattern), "/var/camera/videos/%s",
 *             params->pattern);
 *    if (glob(path_pattern, 0, NULL, &globbuf) == 0) {
 *        for (size_t i = 0; i < globbuf.gl_pathc; i++) {
 *            unlink(globbuf.gl_pathv[i]);
 *        }
 *        globfree(&globbuf);
 *    }
 *    ```
 */
AXIS2_EXTERN axis2_status_t AXIS2_CALL
camera_device_delete_files_impl(
    const axutil_env_t *env,
    const file_delete_params_t *params)
{
    /* STUB IMPLEMENTATION - USER MUST REPLACE */

    if (!env || !params)
    {
        return AXIS2_FAILURE;
    }

    /* Security validation - reject path traversal attempts */
    if (params->pattern && strstr(params->pattern, ".."))
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI,
            "STUB: Security violation - path traversal detected in pattern: %s",
            params->pattern);
        return AXIS2_FAILURE;
    }

    /* Require a pattern for deletion */
    if (!params->pattern || strlen(params->pattern) == 0)
    {
        AXIS2_LOG_ERROR(env->log, AXIS2_LOG_SI,
            "STUB: Missing required 'pattern' parameter for file deletion");
        return AXIS2_FAILURE;
    }

    /* Log the stub operation */
    AXIS2_LOG_INFO(env->log,
        "STUB: Delete files request - pattern: %s",
        params->pattern);

    AXIS2_LOG_WARNING(env->log, AXIS2_LOG_SI,
        "STUB: camera_device_delete_files_impl() - Replace with storage-specific implementation!");

    /*
     * USER IMPLEMENTATION GOES HERE
     * Replace this entire function with storage-specific code to delete video files
     *
     * Expected behavior:
     * 1. Validate pattern for security (no path traversal)
     * 2. Resolve pattern to list of files to delete:
     *    - Specific filename: delete that file
     *    - Wildcard (*.mp4, VID_2026*): delete matching files
     *    - "today": delete files with today's date in filename
     *    - Date (YYYY-MM-DD): delete files from that date
     *    - "*": delete all video files
     * 3. Delete each matching file
     * 4. Return AXIS2_SUCCESS if all deletions succeeded
     */

    return AXIS2_SUCCESS; /* Stub always succeeds for testing */
}

/* ========================================================================
 * END STUB IMPLEMENTATIONS
 * ======================================================================== */

/**
 * JSON Service Entry Point - Processes camera control requests
 */
AXIS2_EXTERN json_object* AXIS2_CALL
camera_control_service_invoke_json(const axutil_env_t *env,
                                  json_object *json_request)
{
    json_object *response = NULL;
    json_object *action_obj = NULL;
    const char *action = NULL;

    if (!env || !json_request)
    {
        return create_error_response(env, "Invalid request parameters");
    }

    /* DEBUG: Print the received JSON request */
    const char *json_string = json_object_to_json_string(json_request);
    AXIS2_LOG_INFO(env->log,
        "[CAMERA_DEBUG] Received JSON request: %s", json_string ? json_string : "NULL");
    printf("[CAMERA_DEBUG] Received JSON request: %s\n", json_string ? json_string : "NULL");

    /* Extract action from JSON request */
    if (!json_object_object_get_ex(json_request, "action", &action_obj))
    {
        AXIS2_LOG_INFO(env->log,
            "[CAMERA_DEBUG] json_object_object_get_ex returned FALSE for 'action' key");
        printf("[CAMERA_DEBUG] Failed to find 'action' key in JSON object\n");
        return create_error_response(env, "Missing 'action' parameter");
    }

    action = json_object_get_string(action_obj);
    if (!action)
    {
        return create_error_response(env, "Invalid 'action' parameter");
    }

    AXIS2_LOG_DEBUG(env->log, AXIS2_LOG_SI, "Processing camera action: %s", action);

    /* Route to appropriate camera operation
     * Accept both snake_case (Axis2/C style) and camelCase (user-friendly) action names
     * Reference: Kanaha implementation accepts both for API compatibility
     */
    if (strcmp(action, "start_recording") == 0 || strcmp(action, "startRecording") == 0)
    {
        /* Handle start recording */
        const char *json_str = json_object_to_json_string(json_request);
        camera_recording_params_t *params = camera_recording_params_create_from_json(env, json_str);

        if (!params)
        {
            return create_error_response(env, "Failed to parse recording parameters");
        }

        /* Validate required parameters */
        if (!params->clip_name || !is_valid_clip_name(params->clip_name))
        {
            camera_recording_params_free(params, env);
            return create_error_response(env, "Invalid or missing clip_name");
        }

        if (params->quality && !is_valid_quality(params->quality))
        {
            camera_recording_params_free(params, env);
            return create_error_response(env, "Invalid quality setting");
        }

        /* Call user-implementable function */
        axis2_status_t result = camera_device_start_recording_impl(env, params);

        if (result == AXIS2_SUCCESS)
        {
            response = create_success_response(env, "Recording started successfully");
        }
        else
        {
            response = create_error_response(env, "Failed to start recording");
        }

        camera_recording_params_free(params, env);
    }
    else if (strcmp(action, "stop_recording") == 0 || strcmp(action, "stopRecording") == 0)
    {
        /* Handle stop recording */
        axis2_status_t result = camera_device_stop_recording_impl(env);

        if (result == AXIS2_SUCCESS)
        {
            response = create_success_response(env, "Recording stopped successfully");
        }
        else
        {
            response = create_error_response(env, "Failed to stop recording");
        }
    }
    else if (strcmp(action, "get_status") == 0 || strcmp(action, "getStatus") == 0)
    {
        /* Handle status request */
        camera_status_t *status = camera_device_get_status_impl(env);

        if (status)
        {
            response = json_object_new_object();
            json_object_object_add(response, "success", json_object_new_boolean(1));
            json_object_object_add(response, "state",
                json_object_new_string(status->state ? status->state : "unknown"));
            json_object_object_add(response, "active_clip",
                json_object_new_string(status->active_clip ? status->active_clip : "none"));
            json_object_object_add(response, "recording_duration",
                json_object_new_int(status->recording_duration));
            json_object_object_add(response, "last_error",
                json_object_new_string(status->last_error ? status->last_error : "none"));

            camera_status_free(status, env);
        }
        else
        {
            response = create_error_response(env, "Failed to get camera status");
        }
    }
    else if (strcmp(action, "configure_settings") == 0 || strcmp(action, "configureSettings") == 0 || strcmp(action, "configure") == 0)
    {
        /* Handle settings configuration */
        const char *json_str = json_object_to_json_string(json_request);
        camera_settings_t *settings = camera_settings_create_from_json(env, json_str);

        if (!settings)
        {
            return create_error_response(env, "Failed to parse camera settings");
        }

        axis2_status_t result = camera_device_configure_settings_impl(env, settings);

        if (result == AXIS2_SUCCESS)
        {
            response = create_success_response(env, "Settings configured successfully");
        }
        else
        {
            response = create_error_response(env, "Failed to configure settings");
        }

        camera_settings_free(settings, env);
    }
    else if (strcmp(action, "sftp_transfer") == 0 || strcmp(action, "sftpTransfer") == 0)
    {
        /* Handle SFTP file transfer */
        const char *json_str = json_object_to_json_string(json_request);
        sftp_transfer_params_t *sftp_params = sftp_transfer_params_create_from_json(env, json_str);

        if (!sftp_params)
        {
            return create_error_response(env, "Failed to parse SFTP transfer parameters");
        }

        /* Validate required parameters */
        if (!sftp_params->hostname || !sftp_params->username ||
            !sftp_params->local_file_path || !sftp_params->private_key_path)
        {
            sftp_transfer_params_free(sftp_params, env);
            return create_error_response(env, "Missing required SFTP parameters (hostname, username, local_file_path, private_key_path)");
        }

        /* Call user-implementable function */
        axis2_status_t result = camera_device_sftp_transfer_impl(env, sftp_params);

        if (result == AXIS2_SUCCESS)
        {
            response = create_success_response(env, "File transferred successfully via SFTP");
        }
        else
        {
            response = create_error_response(env, "Failed to transfer file via SFTP");
        }

        sftp_transfer_params_free(sftp_params, env);
    }
    else if (strcmp(action, "list_files") == 0 || strcmp(action, "listFiles") == 0)
    {
        /* Handle list files request */
        const char *json_str = json_object_to_json_string(json_request);
        file_list_params_t *params = file_list_params_create_from_json(env, json_str);

        /* Call user-implementable function */
        file_list_result_t *result = camera_device_list_files_impl(env, params);

        if (result)
        {
            /* Build JSON response with file list */
            response = json_object_new_object();
            json_object_object_add(response, "success", json_object_new_boolean(1));
            json_object_object_add(response, "file_count", json_object_new_int(result->file_count));
            json_object_object_add(response, "total_size", json_object_new_int64(result->total_size));
            json_object_object_add(response, "directory",
                json_object_new_string(result->directory ? result->directory : ""));

            /* Add files array */
            json_object *files_array = json_object_new_array();
            for (int i = 0; i < result->file_count && result->files; i++)
            {
                json_object *file_obj = json_object_new_object();
                json_object_object_add(file_obj, "name",
                    json_object_new_string(result->files[i].name ? result->files[i].name : ""));
                json_object_object_add(file_obj, "size",
                    json_object_new_int64(result->files[i].size));
                json_object_object_add(file_obj, "modified",
                    json_object_new_string(result->files[i].modified ? result->files[i].modified : ""));
                json_object_array_add(files_array, file_obj);
            }
            json_object_object_add(response, "files", files_array);

            file_list_result_free(result, env);
        }
        else
        {
            response = create_error_response(env, "Failed to list files");
        }

        if (params)
            file_list_params_free(params, env);
    }
    else if (strcmp(action, "delete_files") == 0 || strcmp(action, "deleteFiles") == 0)
    {
        /* Handle delete files request */
        const char *json_str = json_object_to_json_string(json_request);
        file_delete_params_t *params = file_delete_params_create_from_json(env, json_str);

        if (!params || !params->pattern || strlen(params->pattern) == 0)
        {
            if (params)
                file_delete_params_free(params, env);
            return create_error_response(env, "Missing required 'pattern' parameter");
        }

        /* Call user-implementable function */
        axis2_status_t result = camera_device_delete_files_impl(env, params);

        if (result == AXIS2_SUCCESS)
        {
            response = create_success_response(env, "Files deleted successfully");
        }
        else
        {
            response = create_error_response(env, "Failed to delete files");
        }

        file_delete_params_free(params, env);
    }
    else
    {
        /* Unknown action */
        char error_msg[256];
        snprintf(error_msg, sizeof(error_msg), "Unknown action: %s", action);
        response = create_error_response(env, error_msg);
    }

    return response;
}

/* HTTP/2 Pure JSON Architecture - No SOAP skeleton functions required */

/* Utility Functions */

/**
 * Create JSON error response
 */
static json_object* create_error_response(const axutil_env_t *env,
                                         const axis2_char_t *error_message)
{
    json_object *response = json_object_new_object();
    json_object_object_add(response, "success", json_object_new_boolean(0));
    json_object_object_add(response, "error",
        json_object_new_string(error_message ? error_message : "Unknown error"));
    return response;
}

/**
 * Create JSON success response
 */
static json_object* create_success_response(const axutil_env_t *env,
                                           const axis2_char_t *message)
{
    json_object *response = json_object_new_object();
    json_object_object_add(response, "success", json_object_new_boolean(1));
    json_object_object_add(response, "message",
        json_object_new_string(message ? message : "Operation successful"));
    return response;
}

/**
 * Validate clip name
 */
static axis2_bool_t is_valid_clip_name(const axis2_char_t *clip_name)
{
    if (!clip_name || strlen(clip_name) == 0 || strlen(clip_name) > CAMERA_CLIP_NAME_MAX_LENGTH)
        return AXIS2_FALSE;

    /* Check for valid filename characters (basic validation) */
    for (int i = 0; clip_name[i] != '\0'; i++)
    {
        char c = clip_name[i];
        if (!isalnum(c) && c != '_' && c != '-' && c != '.')
            return AXIS2_FALSE;
    }

    return AXIS2_TRUE;
}

/**
 * Validate quality setting
 */
static axis2_bool_t is_valid_quality(const axis2_char_t *quality)
{
    if (!quality)
        return AXIS2_TRUE; /* Quality is optional */

    /* Accept common quality settings */
    const char *valid_qualities[] = {"4K", "1080p", "720p", "480p", "360p", "high", "medium", "low", NULL};

    for (int i = 0; valid_qualities[i] != NULL; i++)
    {
        if (strcmp(quality, valid_qualities[i]) == 0)
            return AXIS2_TRUE;
    }

    return AXIS2_FALSE;
}

/**
 * Sanitize input string
 */
AXIS2_EXTERN axis2_char_t* AXIS2_CALL
camera_service_sanitize_input(const axutil_env_t *env,
                             const axis2_char_t *input,
                             int max_length)
{
    axis2_char_t *sanitized = NULL;
    int len;

    if (!env || !input)
        return NULL;

    len = strlen(input);
    if (len > max_length)
        len = max_length;

    sanitized = AXIS2_MALLOC(env->allocator, len + 1);
    if (!sanitized)
        return NULL;

    /* Basic sanitization - remove potential harmful characters */
    int j = 0;
    for (int i = 0; i < len && input[i] != '\0'; i++)
    {
        char c = input[i];
        /* Allow alphanumeric, spaces, and common punctuation */
        if (isalnum(c) || c == ' ' || c == '_' || c == '-' || c == '.' || c == '/')
        {
            sanitized[j++] = c;
        }
    }
    sanitized[j] = '\0';

    return sanitized;
}