/*
 * FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 * Copyright (C) 2005-2016, Anthony Minessale II <anthm@freeswitch.org>
 *
 * Version: MPL 1.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is FreeSWITCH Modular Media Switching Software Library / Soft-Switch Application
 *
 * The Initial Developer of the Original Code is
 * Anthony Minessale II <anthm@freeswitch.org>
 * Portions created by the Initial Developer are Copyright (C)
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *
 * Christopher M. Rienzo <chris@rienzo.com>
 * Darren Schreiber <d@d-man.org>
 *
 * Maintainer: Christopher M. Rienzo <chris@rienzo.com>
 *
 * mod_http_cache.c -- HTTP GET with caching
 *                  -- designed for downloading audio files from a webserver for playback
 *
 */
#include <switch.h>
#include <switch_curl.h>
#include "aws.h"
#include "azure.h"

#include <stdlib.h>

#ifdef WIN32
#include <BaseTsd.h>
typedef SSIZE_T ssize_t;

#include <stdlib.h>
#include <ctype.h>

char *strcasestr(const char *str, const char *pattern) {
	size_t i;

	if (!*pattern)
		return (char*)str;

	for (; *str; str++) {
		if (toupper(*str) == toupper(*pattern)) {
			for (i = 1;; i++) {
				if (!pattern[i])
					return (char*)str;
				if (toupper(str[i]) != toupper(pattern[i]))
					break;
			}
		}
	}
	return NULL;
}

char *strndup(const char *s, size_t n)
{
	char *p;

	p = (char *)malloc(n + 1);
	if (p == NULL)
		return NULL;
	memcpy(p, s, n);
	p[n] = '\0';
	return p;
}
#endif

/* 253 max domain size + '/' + NUL byte */
#define DOMAIN_BUF_SIZE 255

/* Defines module interface to FreeSWITCH */
SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_http_cache_shutdown);
SWITCH_MODULE_LOAD_FUNCTION(mod_http_cache_load);
SWITCH_MODULE_DEFINITION(mod_http_cache, mod_http_cache_load, mod_http_cache_shutdown, NULL);
SWITCH_STANDARD_API(http_cache_get);
SWITCH_STANDARD_API(http_cache_put);
SWITCH_STANDARD_API(http_cache_tryget);
SWITCH_STANDARD_API(http_cache_clear);
SWITCH_STANDARD_API(http_cache_remove);
SWITCH_STANDARD_API(http_cache_prefetch);

#define DOWNLOAD_NEEDED "download"
#define DOWNLOAD 1
#define PREFETCH 2

typedef struct url_cache url_cache_t;

struct block_info {
	FILE *f;
	size_t bytes_to_read;
};
typedef struct block_info block_info_t;

/**
 * status if the cache entry
 */
enum cached_url_status {
	/** downloading */
	CACHED_URL_RX_IN_PROGRESS,
	/** marked for removal */
	CACHED_URL_REMOVE,
	/** available */
	CACHED_URL_AVAILABLE
};
typedef enum cached_url_status cached_url_status_t;

/**
 * Cached URL information
 */
struct cached_url {
	/** The URL that was cached */
	char *url;
	/** The path and name of the cached URL */
	char *filename;
	/** File extension */
	char *extension;
	/** Content-Type of this URL (audio/3gpp) */
	char *content_type;
	/** Content-Type parameters  (codecs=samr) */
	const char *content_type_params;
	/** The size of the cached URL, in bytes */
	size_t size;
	/** URL use flag */
	int used;
	/** Status of this entry */
	cached_url_status_t status;
	/** Number of sessions waiting for this URL */
	int waiters;
	/** time when downloaded */
	switch_time_t download_time;
	/** nanoseconds until stale */
	switch_time_t max_age;
};
typedef struct cached_url cached_url_t;

static cached_url_t *cached_url_create(url_cache_t *cache, const char *url, const char *filename);
static void cached_url_destroy(cached_url_t *url, switch_memory_pool_t *pool);

/**
 * Data for write_file_callback()
 */
struct http_get_data {
	/** File descriptor for the cached URL */
	int fd;
	/** The cached URL data */
	cached_url_t *url;
};
typedef struct http_get_data http_get_data_t;

static switch_status_t http_get(url_cache_t *cache, http_profile_t *profile, cached_url_t *url, switch_core_session_t *session);
static size_t get_file_callback(void *ptr, size_t size, size_t nmemb, void *get);
static size_t get_header_callback(void *ptr, size_t size, size_t nmemb, void *url);
static void process_cache_control_header(cached_url_t *url, char *data);
static void process_content_type_header(cached_url_t *url, char *data);

static switch_status_t http_put(url_cache_t *cache, http_profile_t *profile, switch_core_session_t *session, const char *url, const char *filename, int cache_local_file, long *httpRes);

/**
 * Queue used for clock cache replacement algorithm.  This
 * queue has been simplified since replacement only happens
 * once it is filled.
 */
struct simple_queue {
	/** The queue data */
	void **data;
	/** queue bounds */
	size_t max_size;
	/** queue size */
	size_t size;
	/** Current index */
	int pos;
};
typedef struct simple_queue simple_queue_t;

/**
 * The cache
 */
struct url_cache {
	/** The maximum number of URLs to cache */
	int max_url;
	/** The maximum size of this cache, in bytes */
	size_t max_size;
	/** The default time to allow a cached URL to live, if none is specified */
	switch_time_t default_max_age;
	/** The current size of this cache, in bytes */
	size_t size;
	/** The location of the cache in the filesystem */
	char *location;
	/** HTTP profiles */
	switch_hash_t *profiles;
	/** profiles mapped by FQDN */
	switch_hash_t *fqdn_profiles;
	/** Cache mapped by URL */
	switch_hash_t *map;
	/** Cached URLs queued for replacement */
	simple_queue_t queue;
	/** Synchronizes access to cache */
	switch_mutex_t *mutex;
	/** Memory pool */
	switch_memory_pool_t *pool;
	/** Number of cache hits */
	int hits;
	/** Number of cache misses */
	int misses;
	/** Number of cache errors */
	int errors;
	/** The prefetch queue */
	switch_queue_t *prefetch_queue;
	/** Max size of prefetch queue */
	int prefetch_queue_size;
	/** Size of prefetch thread pool */
	int prefetch_thread_count;
	/** Shutdown flag */
	int shutdown;
	/** Synchronizes shutdown of cache */
	switch_thread_rwlock_t *shutdown_lock;
	/** SSL cert filename */
	char *ssl_cacert;
	/** Verify certificate */
	int ssl_verifypeer;
	/** Verify that hostname matches certificate */
	int ssl_verifyhost;
	/** True if http/https file formats should be loaded */
	int enable_file_formats;
	/** How long to wait, in seconds, for TCP connection.  If 0, use default value of 300 seconds */
	long connect_timeout;
	/** How long to wait, in seconds, for download of file.  If 0, use default value of 300 seconds */
	long download_timeout;
};
static url_cache_t gcache;

static char *url_cache_get(url_cache_t *cache, http_profile_t *profile, switch_core_session_t *session, const char *url, int download, int refresh, switch_memory_pool_t *pool);
static switch_status_t url_cache_add(url_cache_t *cache, switch_core_session_t *session, cached_url_t *url);
static void url_cache_remove(url_cache_t *cache, switch_core_session_t *session, cached_url_t *url);
static void url_cache_remove_soft(url_cache_t *cache, switch_core_session_t *session, cached_url_t *url);
static switch_status_t url_cache_replace(url_cache_t *cache, switch_core_session_t *session);
static void url_cache_lock(url_cache_t *cache, switch_core_session_t *session);
static void url_cache_unlock(url_cache_t *cache, switch_core_session_t *session);
static void url_cache_clear(url_cache_t *cache, switch_core_session_t *session);
static http_profile_t *url_cache_http_profile_find(url_cache_t *cache, const char *name);
static http_profile_t *url_cache_http_profile_find_by_fqdn(url_cache_t *cache, const char *url);


/**
 * Parse FQDN from URL
 */
static void parse_domain(const char *url, char *domain_buf, int domain_buf_len)
{
	char *end;
	char *start;
	domain_buf[0] = '\0';
	if (zstr(url)) {
		return;
	}
	start = strstr(url, "://");
	if (!start) {
		return;
	}
	start += 3;
	if (!*start) {
		return;
	}
	strncpy(domain_buf, start, domain_buf_len);
	end = strchr(domain_buf, '/');
	if (end) {
		*end = '\0';
	} else {
		/* bad URL */
		domain_buf[0] = '\0';
	}
}

static size_t read_callback(void *ptr, size_t size, size_t nmemb, void *userp)
{
	block_info_t *block_info = (block_info_t *) userp;

	if (size * nmemb <= block_info->bytes_to_read) {
		block_info->bytes_to_read -= size * nmemb;
		return fread(ptr, size, nmemb, block_info->f);
	} else {
		int i = block_info->bytes_to_read;
		block_info->bytes_to_read = 0;
		return fread(ptr, 1, i, block_info->f);
	}
}

/**
 * Put a file to the URL
 * @param cache the cache
 * @param profile the HTTP profile
 * @param session the (optional) session uploading the file
 * @param url The URL
 * @param filename The file to upload
 * @param cache_local_file true if local file should be mapped to url in cache
 * @return SWITCH_STATUS_SUCCESS if successful
 */
static switch_status_t http_put(url_cache_t *cache, http_profile_t *profile, switch_core_session_t *session, const char *url, const char *filename, int cache_local_file, long *httpRes)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;

	switch_curl_slist_t *headers = NULL;  /* optional linked-list of HTTP headers */
	char *ext;  /* file extension, used for MIME type identification */
	const char *mime_type = "application/octet-stream";
	char *buf;

	CURL *curl_handle = NULL;
	struct stat file_info = {0};
	FILE *file_to_put = NULL;

	switch_size_t sent_bytes = 0;
	switch_size_t bytes_per_block;
	unsigned int block_num = 1;
	*httpRes = 0;

	/* guess what type of mime content this is going to be */
	if ((ext = strrchr(filename, '.'))) {
		ext++;
		if (!(mime_type = switch_core_mime_ext2type(ext))) {
			mime_type = "application/octet-stream";
		}
	}

	/* find profile for domain */
	if (!profile) {
		profile = url_cache_http_profile_find_by_fqdn(cache, url);
	}

	/* open file and get the file size */
	switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "opening %s for upload to %s\n", filename, url);

	file_to_put = fopen(filename, "rb");
	if (!file_to_put) {
		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "fopen() error: %s\n", strerror(errno));
		return SWITCH_STATUS_FALSE;
	}

	if (fstat(fileno(file_to_put), &file_info) == -1) {
		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "fstat() error: %s\n", strerror(errno));
		fclose(file_to_put);
		return SWITCH_STATUS_FALSE;
	}

	buf = switch_mprintf("Content-Type: %s", mime_type);

	bytes_per_block = profile && profile->bytes_per_block ? profile->bytes_per_block : file_info.st_size;

	// for Azure - will re-upload all of the file on error we could just upload the blocks
	// that failed.  Also, we could do it all in parallel.

	while (sent_bytes < file_info.st_size) {
		switch_size_t content_length = file_info.st_size - sent_bytes < bytes_per_block ? file_info.st_size - sent_bytes : bytes_per_block;
		block_info_t block_info = { file_to_put, content_length };
		// make a copy of the URL so we can add the query string to ir
		char *query_string = NULL;
		char *full_url = NULL;

		headers = switch_curl_slist_append(NULL, buf);
		if (profile && profile->append_headers_ptr) {
			profile->append_headers_ptr(profile, headers, "PUT", content_length, mime_type, url, block_num, &query_string);
		}

		if (query_string) {
			full_url = switch_mprintf("%s?%s", url, query_string);
			free(query_string);
		} else {
			switch_strdup(full_url, url);
		}

		// seek to the correct position in the file
		if (fseek(file_to_put, sent_bytes, SEEK_SET) != 0) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Failed to seek file - errno=%d\n", errno);
			status = SWITCH_STATUS_FALSE;
			goto done;
		}

		curl_handle = switch_curl_easy_init();
		if (!curl_handle) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "switch_curl_easy_init() failure\n");
			status = SWITCH_STATUS_FALSE;
			goto done;
		}
		switch_curl_easy_setopt(curl_handle, CURLOPT_UPLOAD, 1);
		switch_curl_easy_setopt(curl_handle, CURLOPT_PUT, 1);
		switch_curl_easy_setopt(curl_handle, CURLOPT_NOSIGNAL, 1);
		switch_curl_easy_setopt(curl_handle, CURLOPT_HTTPHEADER, headers);
		switch_curl_easy_setopt(curl_handle, CURLOPT_URL, full_url);

		/* we want to use our own read function so we can send a portion of the file */
		switch_curl_easy_setopt(curl_handle, CURLOPT_READFUNCTION, read_callback);
		switch_curl_easy_setopt(curl_handle, CURLOPT_READDATA, &block_info);

		switch_curl_easy_setopt(curl_handle, CURLOPT_INFILESIZE_LARGE,(curl_off_t) content_length);
		switch_curl_easy_setopt(curl_handle, CURLOPT_FOLLOWLOCATION, 1);
		switch_curl_easy_setopt(curl_handle, CURLOPT_MAXREDIRS, 10);
		switch_curl_easy_setopt(curl_handle, CURLOPT_USERAGENT, "freeswitch-http-cache/1.0");
		if (cache->connect_timeout > 0) {
			switch_curl_easy_setopt(curl_handle, CURLOPT_CONNECTTIMEOUT, cache->connect_timeout);
		}
		if (!cache->ssl_verifypeer) {
			switch_curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYPEER, 0L);
		} else {
			/* this is the file with all the trusted certificate authorities */
			if (!zstr(cache->ssl_cacert)) {
				switch_curl_easy_setopt(curl_handle, CURLOPT_CAINFO, cache->ssl_cacert);
			}
			/* verify that the host name matches the cert */
			if (!cache->ssl_verifyhost) {
				switch_curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYHOST, 0L);
			}
		}
		switch_curl_easy_perform(curl_handle);
		switch_curl_easy_getinfo(curl_handle, CURLINFO_RESPONSE_CODE, httpRes);
		switch_curl_easy_cleanup(curl_handle);

		if (*httpRes == 200 || *httpRes == 201 || *httpRes == 202 || *httpRes == 204) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "%s saved to %s\n", filename, full_url);
		} else {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "Received HTTP error %ld trying to save %s to %s\n", *httpRes, filename, url);
			status = SWITCH_STATUS_GENERR;
		}

	done:
		switch_safe_free(full_url);

		if (headers) {
			switch_curl_slist_free_all(headers);
		}

		if (status == SWITCH_STATUS_SUCCESS) {
			sent_bytes += content_length;
			block_num ++;
		} else {
			// there's no point doing the rest of the blocks if one failed
			break;
		}
	}	//while

	fclose(file_to_put);

	if (status == SWITCH_STATUS_SUCCESS) {
		if (cache_local_file) {
			cached_url_t *u = NULL;
			/* save to cache */
			url_cache_lock(cache, session);
			u = cached_url_create(cache, url, filename);
			u->size = file_info.st_size;
			u->status = CACHED_URL_AVAILABLE;
			if (url_cache_add(cache, session, u) != SWITCH_STATUS_SUCCESS) {
				/* This error should never happen */
				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_CRIT, "Failed to add URL to cache!\n");
				cached_url_destroy(u, cache->pool);
			}
			url_cache_unlock(cache, session);
		}

		if (profile && profile->finalise_put_ptr) {
			profile->finalise_put_ptr(profile, url, block_num);
		}
	}

	switch_safe_free(buf);

	return status;
}

/**
 * Called by libcurl to write result of HTTP GET to a file
 * @param ptr The data to write
 * @param size The size of the data element to write
 * @param nmemb The number of elements to write
 * @param get Info about this current GET request
 * @return bytes processed
 */
static size_t get_file_callback(void *ptr, size_t size, size_t nmemb, void *get)
{
	size_t realsize = (size * nmemb);
	http_get_data_t *get_data = get;
	ssize_t bytes_written = write(get_data->fd, ptr, realsize);
	size_t result = 0;
	if (bytes_written == -1) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "write(): %s\n", strerror(errno));
	} else {
		if (bytes_written != realsize) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "write(): short write!\n");
		}
		get_data->url->size += bytes_written;
		result = bytes_written;
	}

	return result;
}

/**
 * trim whitespace characters from string
 * @param str the string to trim
 * @return the trimmed string
 */
static char *trim(char *str)
{
	size_t len;
	int i;

	if (zstr(str)) {
		return str;
	}
	len = strlen(str);

	/* strip whitespace from front */
	for (i = 0; i < len; i++) {
		if (!isspace(str[i])) {
			str = &str[i];
			len -= i;
			break;
		}
	}
	if (zstr(str)) {
		return str;
	}

	/* strip whitespace from end */
	for (i = len - 1; i >= 0; i--) {
		if (!isspace(str[i])) {
			break;
		}
		str[i] = '\0';
	}
	return str;
}

#define MAX_AGE "max-age="
/**
 * cache-control: max-age=123456
 * Only support max-age.  All other params are ignored.
 */
static void process_cache_control_header(cached_url_t *url, char *data)
{
	char *max_age_str;
	switch_time_t max_age;
	int i;

	/* trim whitespace and check if empty */
	data = trim(data);
	if (zstr(data)) {
		return;
	}

	/* find max-age param */
	max_age_str = strcasestr(data, MAX_AGE);
	if (zstr(max_age_str)) {
		return;
	}

	/* find max-age value */
	max_age_str = max_age_str + (sizeof(MAX_AGE) - 1);
	if (zstr(max_age_str)) {
		return;
	}
	for (i = 0; i < strlen(max_age_str); i++) {
		if (!isdigit(max_age_str[i])) {
			max_age_str[i] = '\0';
			break;
		}
	}
	if (zstr(max_age_str)) {
		return;
	}
	max_age = atoi(max_age_str);

	if (max_age < 0) {
		return;
	}

	url->max_age = max_age * 1000 * 1000;
	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "setting max age to %u seconds from now\n", (int)max_age);
}

/**
 * Content-Type: audio/mpeg; foo=bar
 */
static void process_content_type_header(cached_url_t *url, char *data)
{
	char *params;

	/* trim whitespace and check if empty */
	data = trim(data);
	if (zstr(data)) {
		return;
	}

	/* copy header, removing any params */
	url->content_type = strdup(data);
	params = strchr(url->content_type, ';');
	if (params) {
		*params = '\0';
		url->content_type_params = trim(++params);
	}
}

#define CACHE_CONTROL_HEADER "cache-control:"
#define CACHE_CONTROL_HEADER_LEN (sizeof(CACHE_CONTROL_HEADER) - 1)
#define CONTENT_TYPE_HEADER "content-type:"
#define CONTENT_TYPE_HEADER_LEN (sizeof(CONTENT_TYPE_HEADER) - 1)
/**
 * Called by libcurl to process headers from HTTP GET response
 * @param ptr the header data
 * @param size The size of the data element to write
 * @param nmemb The number of elements to write
 * @param get get data
 * @return bytes processed
 */
static size_t get_header_callback(void *ptr, size_t size, size_t nmemb, void *get)
{
	size_t realsize = (size * nmemb);
	cached_url_t *url = get;
	char *header = NULL;

	/* validate length... Apache and IIS won't send a header larger than 16 KB */
	if (realsize == 0 || realsize > 1024 * 16) {
		return realsize;
	}

	/* get the header, adding NULL terminator if there isn't one */
	switch_zmalloc(header, realsize + 1);
	strncpy(header, (char *)ptr, realsize);
	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "%s", header);

	/* check which header this is and process it */
	if (!strncasecmp(CACHE_CONTROL_HEADER, header, CACHE_CONTROL_HEADER_LEN)) {
		process_cache_control_header(url, header + CACHE_CONTROL_HEADER_LEN);
	} else if (!strncasecmp(CONTENT_TYPE_HEADER, header, CONTENT_TYPE_HEADER_LEN)) {
		process_content_type_header(url, header + CONTENT_TYPE_HEADER_LEN);
	}

	switch_safe_free(header);
	return realsize;
}

/**
 * Get exclusive access to the cache
 * @param cache The cache
 * @param session The session acquiring the cache
 */
static void url_cache_lock(url_cache_t *cache, switch_core_session_t *session)
{
	switch_mutex_lock(cache->mutex);
	switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "Locked cache\n");
}

/**
 * Relinquish exclusive access to the cache
 * @param cache The cache
 * @param session The session relinquishing the cache
 */
static void url_cache_unlock(url_cache_t *cache, switch_core_session_t *session)
{
	switch_mutex_unlock(cache->mutex);
	switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "Unlocked cache\n");
}

/**
 * Empties the cache
 */
static void url_cache_clear(url_cache_t *cache, switch_core_session_t *session)
{
	int i;

	url_cache_lock(cache, session);

	// remove each cached URL from the hash and the queue
	for (i = 0; i < cache->queue.max_size; i++) {
		cached_url_t *url = cache->queue.data[i];
		if (url) {
			switch_core_hash_delete(cache->map, url->url);
			cached_url_destroy(url, cache->pool);
			cache->queue.data[i] = NULL;
		}
	}
	cache->queue.pos = 0;
	cache->queue.size = 0;

	// reset cache stats
	cache->size = 0;
	cache->hits = 0;
	cache->misses = 0;
	cache->errors = 0;

	url_cache_unlock(cache, session);

	switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "Emptied cache\n");
}

/**
 * Get a URL from the cache, add it if it does not exist
 * @param cache The cache
 * @param profile optional profile
 * @param session the (optional) session requesting the URL
 * @param url The URL
 * @param download If DOWNLOAD, the file will be downloaded if it does not exist in the cache.  If PREFETCH, the file will be downloaded if not in cache and not being downloaded by another thread.
 * @param refresh If true, existing cache entry is invalidated
 * @param pool The pool to use for allocating the filename
 * @return The filename or NULL if there is an error
 */
static char *url_cache_get(url_cache_t *cache, http_profile_t *profile, switch_core_session_t *session, const char *url, int download, int refresh, switch_memory_pool_t *pool)
{
	switch_time_t download_timeout_ns = cache->download_timeout * 1000 * 1000;
	char *filename = NULL;
	cached_url_t *u = NULL;
	if (zstr(url)) {
		return NULL;
	}

	url_cache_lock(cache, session);
	u = switch_core_hash_find(cache->map, url);

	if (u && u->status == CACHED_URL_AVAILABLE) {
		if (switch_time_now() >= (u->download_time + u->max_age)) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "Cached URL has expired.\n");
			url_cache_remove_soft(cache, session, u); /* will get permanently deleted upon replacement */
			u = NULL;
		} else if (switch_file_exists(u->filename, pool) != SWITCH_STATUS_SUCCESS) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "Cached URL file is missing.\n");
			url_cache_remove_soft(cache, session, u); /* will get permanently deleted upon replacement */
			u = NULL;
		} else if (refresh) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "Cached URL manually expired.\n");
			url_cache_remove_soft(cache, session, u); /* will get permanently deleted upon replacement */
			u = NULL;
		} else if (u->status == CACHED_URL_RX_IN_PROGRESS && switch_time_now() >= (u->download_time + download_timeout_ns)) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "Download of URL has timed out.\n");
			u = NULL;
		}
	}

	if (!u && download) {
		/* URL is not cached, let's add it.*/
		/* Set up URL entry and add to map to prevent simultaneous downloads */
		cache->misses++;
		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "Cache MISS: size = %zu (%zu MB), hit ratio = %d/%d\n", cache->queue.size, cache->size / 1000000, cache->hits, cache->hits + cache->misses);
		u = cached_url_create(cache, url, NULL);
		if (url_cache_add(cache, session, u) != SWITCH_STATUS_SUCCESS) {
			/* This error should never happen */
			url_cache_unlock(cache, session);
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_CRIT, "Failed to add URL to cache!\n");
			cached_url_destroy(u, cache->pool);
			return NULL;
		}

		/* download the file */
		url_cache_unlock(cache, session);
		if (http_get(cache, profile, u, session) == SWITCH_STATUS_SUCCESS) {
			/* Got the file, let the waiters know it is available */
			url_cache_lock(cache, session);
			u->status = CACHED_URL_AVAILABLE;
			filename = switch_core_strdup(pool, u->filename);
			cache->size += u->size;
		} else {
			/* Did not get the file, flag for replacement */
			url_cache_lock(cache, session);
			url_cache_remove_soft(cache, session, u);
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "Failed to download URL %s\n", url);
			cache->errors++;
		}
	} else if (!u || (u->status == CACHED_URL_RX_IN_PROGRESS && download != DOWNLOAD)) {
		filename = DOWNLOAD_NEEDED;
	} else {
		/* Wait until file is downloaded */
		if (u->status == CACHED_URL_RX_IN_PROGRESS) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "Waiting for URL %s to be available\n", url);
			u->waiters++;
			url_cache_unlock(cache, session);
			while(u->status == CACHED_URL_RX_IN_PROGRESS && switch_time_now() < (u->download_time + download_timeout_ns)) {
				switch_sleep(10 * 1000); /* 10 ms */
			}
			url_cache_lock(cache, session);
			u->waiters--;
		}

		/* grab filename if everything is OK */
		if (u->status == CACHED_URL_AVAILABLE) {
			filename = switch_core_strdup(pool, u->filename);
			cache->hits++;
			u->used = 1;
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "Cache HIT: size = %zu (%zu MB), hit ratio = %d/%d\n", cache->queue.size, cache->size / 1000000, cache->hits, cache->hits + cache->misses);
		}
	}
	url_cache_unlock(cache, session);
	return filename;
}

/**
 * Add a URL to the cache.  The caller must lock the cache.
 * @param cache the cache
 * @param session the (optional) session
 * @param url the URL to add
 * @return SWITCH_STATUS_SUCCESS if successful
 */
static switch_status_t url_cache_add(url_cache_t *cache, switch_core_session_t *session, cached_url_t *url)
{
	simple_queue_t *queue = &cache->queue;
	if (queue->size >= queue->max_size && url_cache_replace(cache, session) != SWITCH_STATUS_SUCCESS) {
		return SWITCH_STATUS_FALSE;
	}
	switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "Adding %s(%s) to cache index %d\n", url->url, url->filename, queue->pos);

	queue->data[queue->pos] = url;
	queue->pos = (queue->pos + 1) % queue->max_size;
	queue->size++;
	switch_core_hash_insert(cache->map, url->url, url);
	return SWITCH_STATUS_SUCCESS;
}

/**
 * Select a URL for replacement and remove it from the cache.
 * Currently implemented with the clock replacement algorithm.  It's not
 * great, but is better than least recently used and is simple to implement.
 *
 * @param cache the cache
 * @param session the (optional) session
 * @return SWITCH_STATUS_SUCCESS if successful
 */
static switch_status_t url_cache_replace(url_cache_t *cache, switch_core_session_t *session)
{
	switch_status_t status = SWITCH_STATUS_FALSE;
	int i = 0;
	simple_queue_t *queue = &cache->queue;

	if (queue->size < queue->max_size || queue->size == 0) {
		return SWITCH_STATUS_FALSE;
	}

	for (i = 0; i < queue->max_size * 2; i++) {
		cached_url_t *to_replace = (cached_url_t *)queue->data[queue->pos];

		/* check for queue corruption */
		if (to_replace == NULL) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_CRIT, "Unexpected empty URL at cache index %d\n", queue->pos);
			status = SWITCH_STATUS_SUCCESS;
			break;
		}

		/* check if available for replacement */
		if (!to_replace->used && !to_replace->waiters) {
			/* remove from cache and destroy it */
			url_cache_remove(cache, session, to_replace);
			cached_url_destroy(to_replace, cache->pool);
			status = SWITCH_STATUS_SUCCESS;
			break;
		}

		/* not available for replacement.  Mark as not used and move to back of queue */
		if (to_replace->status == CACHED_URL_AVAILABLE) {
			to_replace->used = 0;
		}
		queue->pos = (queue->pos + 1) % queue->max_size;
	}

	return status;
}

/**
 * Remove a URL from the hash map and mark it as eligible for replacement from the queue.
 */
static void url_cache_remove_soft(url_cache_t *cache, switch_core_session_t *session, cached_url_t *url)
{
	switch_core_hash_delete(cache->map, url->url);
	url->used = 0;
	url->status = CACHED_URL_REMOVE;
}

/**
 * Remove a URL from the front or back of the cache
 * @param cache the cache
 * @param session the (optional) session
 * @param url the URL to remove
 */
static void url_cache_remove(url_cache_t *cache, switch_core_session_t *session, cached_url_t *url)
{
	simple_queue_t *queue;
	cached_url_t *to_remove;

	url_cache_remove_soft(cache, session, url);

	/* make sure cached URL matches the item in the queue and remove it */
	queue = &cache->queue;
	to_remove = (cached_url_t *)queue->data[queue->pos];
	if (url == to_remove) {
		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "Removing %s(%s) from cache index %d\n", url->url, url->filename, queue->pos);
		queue->data[queue->pos] = NULL;
		queue->size--;
	} else {
		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_CRIT, "URL entry, %s, not in cache queue!!!\n", url->url);
	}

	/* adjust cache statistics */
	cache->size -= url->size;
}

/**
 * Find a profile
 */
static http_profile_t *url_cache_http_profile_find(url_cache_t *cache, const char *name)
{
	if (cache && !zstr(name)) {
		return (http_profile_t *)switch_core_hash_find(cache->profiles, name);
	}
	return NULL;
}

/**
 * Find a profile by domain name
 */
static http_profile_t *url_cache_http_profile_find_by_fqdn(url_cache_t *cache, const char *url)
{
	if (cache && !zstr(url)) {
		char fqdn[DOMAIN_BUF_SIZE];
		parse_domain(url, fqdn, DOMAIN_BUF_SIZE);
		if (!zstr_buf(fqdn)) {
			return (http_profile_t *)switch_core_hash_find(cache->fqdn_profiles, fqdn);
		}
	}
	return NULL;
}

/**
 * Find file extension at end of URL.
 * @param url to search
 * @param found_extension
 * @param found_extension_len
 */
static void find_extension(const char *url, const char **found_extension, size_t *found_extension_len)
{
	const char *ext;
	size_t ext_len = 0;

	/* find extension on the end of URL */
	for (ext = &url[strlen(url) - 1]; ext != url; ext--) {
		if (*ext == '/' || *ext == '\\') {
			break;
		}
		if (*ext == '?' || *ext == '#') {
			ext_len = 0;
		} else if (*ext == '.') {
			/* found it */
			*found_extension_len = ext_len;
			*found_extension = ++ext;
			break;
		} else {
			ext_len++;
		}
	}
}

/**
 * Create a cached URL filename.
 * @param cache
 * @param url
 * @param extension if set, extension is duplicated here
 * @return the cached URL filename.  Free when done.
 */
static char *cached_url_filename_create(url_cache_t *cache, const char *url, char **extension)
{
	char *filename;
	char *dirname;
	char uuid_dir[3] = { 0 };
	switch_uuid_t uuid;
	char uuid_str[SWITCH_UUID_FORMATTED_LENGTH + 1] = { 0 };
	const char *found_extension = NULL;
	size_t found_extension_len = 0;

	find_extension(url, &found_extension, &found_extension_len);

	/* filename is constructed from UUID and is stored in cache dir (first 2 characters of UUID) */
	switch_uuid_get(&uuid);
	switch_uuid_format(uuid_str, &uuid);
	strncpy(uuid_dir, uuid_str, 2);
	dirname = switch_mprintf("%s%s%s", cache->location, SWITCH_PATH_SEPARATOR, uuid_dir);

	/* create sub-directory if it doesn't exist */
	switch_dir_make_recursive(dirname, SWITCH_DEFAULT_DIR_PERMS, cache->pool);

	if (!zstr(found_extension) && found_extension_len > 0) {
		char *found_extension_dup = strndup(found_extension, found_extension_len);
		filename = switch_mprintf("%s%s%s.%s", dirname, SWITCH_PATH_SEPARATOR, &uuid_str[2], found_extension_dup);
		if (extension) {
			*extension = found_extension_dup;
		} else {
			free(found_extension_dup);
		}
 	} else {
		filename = switch_mprintf("%s%s%s", dirname, SWITCH_PATH_SEPARATOR, &uuid_str[2]);
		if (extension) {
			*extension = NULL;
		}
	}
	free(dirname);
	return filename;
}

/**
 * Rename cached URL with filename extension if one can be determined
 * @param url the cached URL
 */
static void cached_url_set_extension_from_content_type(cached_url_t *url, switch_core_session_t *session)
{
	if (!url->extension && url->content_type) {
		const char *new_extension = switch_core_mime_type2ext(url->content_type);
		if (new_extension) {
			char *new_filename = switch_mprintf("%s.%s", url->filename, new_extension);
			if (rename(url->filename, new_filename) != -1) {
				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "renamed cached URL to %s\n", new_filename);
				free(url->filename);
				url->filename = new_filename;
				url->extension = strdup(new_extension);
			} else {
				switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_WARNING, "rename(%s): %s\n", new_filename, strerror(errno));
				free(new_filename);
			}
		}
	}
}

/**
 * Create a cached URL entry
 * @param cache the cache
 * @param url the URL to cache
 * @param filename (optional) pre-defined local filename
 * @return the cached URL
 */
static cached_url_t *cached_url_create(url_cache_t *cache, const char *url, const char *filename)
{
	cached_url_t *u = NULL;

	if (zstr(url)) {
		return NULL;
	}

	switch_zmalloc(u, sizeof(cached_url_t));

	/* intialize cached URL */
	if (zstr(filename)) {
		u->filename = cached_url_filename_create(cache, url, &u->extension);
	} else {
		u->filename = strdup(filename);
	}
	u->url = switch_safe_strdup(url);
	u->size = 0;
	u->used = 1;
	u->status = CACHED_URL_RX_IN_PROGRESS;
	u->waiters = 0;
	u->download_time = switch_time_now();
	u->max_age = cache->default_max_age;

	return u;
}

/**
 * Destroy a cached URL (delete file and struct)
 */
static void cached_url_destroy(cached_url_t *url, switch_memory_pool_t *pool)
{
	if (!zstr(url->filename)) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "Deleting %s from cache\n", url->filename);
		switch_file_remove(url->filename, pool);
	}
	switch_safe_free(url->filename);
	switch_safe_free(url->extension);
	switch_safe_free(url->content_type);
	switch_safe_free(url->url);
	switch_safe_free(url);
}

/**
 * Fetch a file via HTTP
 * @param cache the cache
 * @param profile the HTTP profile
 * @param url The cached URL entry
 * @param session the (optional) session
 * @return SWITCH_STATUS_SUCCESS if successful
 */
static switch_status_t http_get(url_cache_t *cache, http_profile_t *profile, cached_url_t *url, switch_core_session_t *session)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	switch_curl_slist_t *headers = NULL;  /* optional linked-list of HTTP headers */
	switch_CURL *curl_handle = NULL;
	http_get_data_t get_data = {0};
	long httpRes = 0;
	int start_time_ms = switch_time_now() / 1000;

	/* set up HTTP GET */
	get_data.fd = 0;
	get_data.url = url;

	/* find profile for domain */
	if (!profile) {
		profile = url_cache_http_profile_find_by_fqdn(cache, url->url);
	}

	if (profile && profile->append_headers_ptr) {
		headers = profile->append_headers_ptr(profile, headers, "GET", 0, "", url->url, 0, NULL);
	}

	curl_handle = switch_curl_easy_init();
	switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_DEBUG, "opening %s for URL cache\n", get_data.url->filename);
	if ((get_data.fd = open(get_data.url->filename, O_CREAT | O_RDWR | O_TRUNC, S_IRUSR | S_IWUSR)) > -1) {
		switch_curl_easy_setopt(curl_handle, CURLOPT_FOLLOWLOCATION, 1);
		switch_curl_easy_setopt(curl_handle, CURLOPT_MAXREDIRS, 10);
		switch_curl_easy_setopt(curl_handle, CURLOPT_NOSIGNAL, 1);
		if (headers) {
			switch_curl_easy_setopt(curl_handle, CURLOPT_HTTPHEADER, headers);
		}
		switch_curl_easy_setopt(curl_handle, CURLOPT_URL, get_data.url->url);
		switch_curl_easy_setopt(curl_handle, CURLOPT_WRITEFUNCTION, get_file_callback);
		switch_curl_easy_setopt(curl_handle, CURLOPT_WRITEDATA, (void *) &get_data);
		switch_curl_easy_setopt(curl_handle, CURLOPT_HEADERFUNCTION, get_header_callback);
		switch_curl_easy_setopt(curl_handle, CURLOPT_WRITEHEADER, (void *) url);
		switch_curl_easy_setopt(curl_handle, CURLOPT_USERAGENT, "freeswitch-http-cache/1.0");
		if (cache->connect_timeout > 0) {
			switch_curl_easy_setopt(curl_handle, CURLOPT_CONNECTTIMEOUT, cache->connect_timeout);
		}
		if (cache->download_timeout > 0) {
			switch_curl_easy_setopt(curl_handle, CURLOPT_TIMEOUT, cache->download_timeout);
		}
		if (!cache->ssl_verifypeer) {
			switch_curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYPEER, 0L);
		} else {
			/* this is the file with all the trusted certificate authorities */
			if (!zstr(cache->ssl_cacert)) {
				switch_curl_easy_setopt(curl_handle, CURLOPT_CAINFO, cache->ssl_cacert);
			}
			/* verify that the host name matches the cert */
			if (!cache->ssl_verifyhost) {
				switch_curl_easy_setopt(curl_handle, CURLOPT_SSL_VERIFYHOST, 0L);
			}
		}
		switch_curl_easy_perform(curl_handle);
		switch_curl_easy_getinfo(curl_handle, CURLINFO_RESPONSE_CODE, &httpRes);
		switch_curl_easy_cleanup(curl_handle);
		close(get_data.fd);
	} else {
		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "open() error: %s\n", strerror(errno));
		status = SWITCH_STATUS_GENERR;
		goto done;
	}

	if (httpRes == 200) {
		int duration_ms = (switch_time_now() / 1000) - start_time_ms;
		if (duration_ms > 500) {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_WARNING, "URL %s downloaded in %d ms\n", url->url, duration_ms);
		} else {
			switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_INFO, "URL %s downloaded in %d ms\n", url->url, duration_ms);
		}
		if (!url->extension) {
			cached_url_set_extension_from_content_type(url, session);
		}
	} else {
		url->size = 0; // nothing downloaded or download interrupted
		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_ERROR, "Received HTTP error %ld trying to fetch %s\n", httpRes, url->url);
		status = SWITCH_STATUS_GENERR;
		goto done;
	}

done:

	if (headers) {
		switch_curl_slist_free_all(headers);
	}

	return status;
}

/**
 * Empties the entire cache
 * @param cache the cache to empty
 */
static void setup_dir(url_cache_t *cache)
{
	int i;

	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "setting up %s\n", cache->location);
	switch_dir_make_recursive(cache->location, SWITCH_DEFAULT_DIR_PERMS, cache->pool);

	for (i = 0x00; i <= 0xff; i++) {
		switch_dir_t *dir = NULL;
		char *dirname = switch_mprintf("%s%s%02x", cache->location, SWITCH_PATH_SEPARATOR, i);
		if (switch_dir_open(&dir, dirname, cache->pool) == SWITCH_STATUS_SUCCESS) {
			char filenamebuf[256] = { 0 };
			const char *filename = NULL;
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "deleting cache files in %s...\n", dirname);
			for(filename = switch_dir_next_file(dir, filenamebuf, sizeof(filenamebuf)); filename;
					filename = switch_dir_next_file(dir, filenamebuf, sizeof(filenamebuf))) {
				char *path = switch_mprintf("%s%s%s", dirname, SWITCH_PATH_SEPARATOR, filename);
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG, "deleting: %s\n", path);
				switch_file_remove(path, cache->pool);
				switch_safe_free(path);
			}
			switch_dir_close(dir);
		}
		switch_safe_free(dirname);
	}
}

#define HTTP_PREFETCH_SYNTAX "{param=val}<url>"
SWITCH_STANDARD_API(http_cache_prefetch)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	char *url;

	if (zstr(cmd)) {
		stream->write_function(stream, "USAGE: %s\n", HTTP_PREFETCH_SYNTAX);
		return SWITCH_STATUS_SUCCESS;
	}

	/* send to thread pool */
	url = switch_mprintf("{prefetch=true}%s", cmd);
	if (switch_queue_trypush(gcache.prefetch_queue, url) != SWITCH_STATUS_SUCCESS) {
		switch_safe_free(url);
		switch_log_printf(SWITCH_CHANNEL_SESSION_LOG(session), SWITCH_LOG_WARNING, "Failed to queue prefetch request\n");
		stream->write_function(stream, "-ERR\n");
	} else {
		stream->write_function(stream, "+OK\n");
	}

	return status;
}

#define HTTP_GET_SYNTAX "{param=val}<url>"
/**
 * Get a file from the cache, download if it isn't cached
 */
SWITCH_STANDARD_API(http_cache_get)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	switch_memory_pool_t *lpool = NULL;
	switch_memory_pool_t *pool = NULL;
	http_profile_t *profile = NULL;
	char *filename;
	switch_event_t *params = NULL;
	char *url;
	int refresh = SWITCH_FALSE;
	int download = DOWNLOAD;

	if (zstr(cmd)) {
		stream->write_function(stream, "USAGE: %s\n", HTTP_GET_SYNTAX);
		return SWITCH_STATUS_SUCCESS;
	}

	if (session) {
		pool = switch_core_session_get_pool(session);
	} else {
		switch_core_new_memory_pool(&lpool);
		pool = lpool;
	}

	/* parse params and get profile */
	url = switch_core_strdup(pool, cmd);
	if (*url == '{') {
		switch_event_create_brackets(url, '{', '}', ',', &params, &url, SWITCH_FALSE);
	}
	if (params) {
		profile = url_cache_http_profile_find(&gcache, switch_event_get_header(params, "profile"));
		if (switch_true(switch_event_get_header(params, "prefetch"))) {
			download = PREFETCH;
		}
		refresh = switch_true(switch_event_get_header(params, "refresh"));
	}

	filename = url_cache_get(&gcache, profile, session, url, download, refresh, pool);
	if (filename) {
		stream->write_function(stream, "%s", filename);

	} else {
		stream->write_function(stream, "-ERR\n");
		status = SWITCH_STATUS_FALSE;
	}

	if (lpool) {
		switch_core_destroy_memory_pool(&lpool);
	}

	if (params) {
		switch_event_destroy(&params);
	}

	return status;
}

#define HTTP_TRYGET_SYNTAX "{param=val}<url>"
/**
 * Get a file from the cache, fail if download is needed
 */
SWITCH_STANDARD_API(http_cache_tryget)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	switch_memory_pool_t *lpool = NULL;
	switch_memory_pool_t *pool = NULL;
	char *filename;
	switch_event_t *params = NULL;
	char *url;

	if (zstr(cmd)) {
		stream->write_function(stream, "USAGE: %s\n", HTTP_GET_SYNTAX);
		return SWITCH_STATUS_SUCCESS;
	}

	if (session) {
		pool = switch_core_session_get_pool(session);
	} else {
		switch_core_new_memory_pool(&lpool);
		pool = lpool;
	}

	/* parse params */
	url = switch_core_strdup(pool, cmd);
	if (*url == '{') {
		switch_event_create_brackets(url, '{', '}', ',', &params, &url, SWITCH_FALSE);
	}

	filename = url_cache_get(&gcache, NULL, session, url, 0, params ? switch_true(switch_event_get_header(params, "refresh")) : SWITCH_FALSE, pool);
	if (filename) {
		if (!strcmp(DOWNLOAD_NEEDED, filename)) {
			stream->write_function(stream, "-ERR %s\n", DOWNLOAD_NEEDED);
		} else {
			stream->write_function(stream, "%s", filename);
		}
	} else {
		stream->write_function(stream, "-ERR\n");
		status = SWITCH_STATUS_FALSE;
	}

	if (lpool) {
		switch_core_destroy_memory_pool(&lpool);
	}

	if (params) {
		switch_event_destroy(&params);
	}

	return status;
}

#define HTTP_PUT_SYNTAX "{param=val}<url> <file>"
/**
 * Put a file to the server
 */
SWITCH_STANDARD_API(http_cache_put)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	http_profile_t *profile = NULL;
	switch_memory_pool_t *lpool = NULL;
	switch_memory_pool_t *pool = NULL;
	char *args = NULL;
	char *argv[10] = { 0 };
	int argc = 0;
	switch_event_t *params = NULL;
	char *url;
	long httpRes = 0;

	if (session) {
		pool = switch_core_session_get_pool(session);
	} else {
		switch_core_new_memory_pool(&lpool);
		pool = lpool;
	}

	if (zstr(cmd)) {
		stream->write_function(stream, "USAGE: %s\n", HTTP_PUT_SYNTAX);
		status = SWITCH_STATUS_SUCCESS;
		goto done;
	}

	args = strdup(cmd);
	argc = switch_separate_string(args, ' ', argv, (sizeof(argv) / sizeof(argv[0])));
	if (argc != 2) {
		stream->write_function(stream, "USAGE: %s\n", HTTP_PUT_SYNTAX);
		status = SWITCH_STATUS_SUCCESS;
		goto done;
	}

	/* parse params and get profile */
	url = switch_core_strdup(pool, argv[0]);
	if (*url == '{') {
		switch_event_create_brackets(url, '{', '}', ',', &params, &url, SWITCH_FALSE);
	}
	if (params) {
		profile = url_cache_http_profile_find(&gcache, switch_event_get_header(params, "profile"));
	}

	status = http_put(&gcache, profile, session, url, argv[1], 0, &httpRes);
	if (status == SWITCH_STATUS_SUCCESS) {
		stream->write_function(stream, "+OK %ld\n", httpRes);
	} else {
		stream->write_function(stream, "-ERR %ld\n", httpRes);
	}

done:
	switch_safe_free(args);

	if (lpool) {
		switch_core_destroy_memory_pool(&lpool);
	}

	if (params) {
		switch_event_destroy(&params);
	}

	return status;
}

#define HTTP_CACHE_CLEAR_SYNTAX ""
/**
 * Clears the cache
 */
SWITCH_STANDARD_API(http_cache_clear)
{
	if (!zstr(cmd)) {
		stream->write_function(stream, "USAGE: %s\n", HTTP_CACHE_CLEAR_SYNTAX);
	} else {
		url_cache_clear(&gcache, session);
		stream->write_function(stream, "+OK\n");
	}
	return SWITCH_STATUS_SUCCESS;
}

#define HTTP_CACHE_REMOVE_SYNTAX "<url>"
/**
 * Invalidate a cached URL
 */
SWITCH_STANDARD_API(http_cache_remove)
{
	switch_memory_pool_t *lpool = NULL;
	switch_memory_pool_t *pool = NULL;
	switch_event_t *params = NULL;
	char *url;

	if (zstr(cmd)) {
		stream->write_function(stream, "USAGE: %s\n", HTTP_CACHE_REMOVE_SYNTAX);
		return SWITCH_STATUS_SUCCESS;
	}

	if (session) {
		pool = switch_core_session_get_pool(session);
	} else {
		switch_core_new_memory_pool(&lpool);
		pool = lpool;
	}

	/* parse params */
	url = switch_core_strdup(pool, cmd);
	if (*url == '{') {
		switch_event_create_brackets(url, '{', '}', ',', &params, &url, SWITCH_FALSE);
	}

	url_cache_get(&gcache, NULL, session, url, 0, 1, pool);
	stream->write_function(stream, "+OK\n");

	if (lpool) {
		switch_core_destroy_memory_pool(&lpool);
	}

	if (params) {
		switch_event_destroy(&params);
	}

	return SWITCH_STATUS_SUCCESS;
}

/**
 * Thread to prefetch URLs
 * @param thread the thread
 * @param obj started flag
 * @return NULL
 */
static void *SWITCH_THREAD_FUNC prefetch_thread(switch_thread_t *thread, void *obj)
{
	int *started = obj;
	void *url = NULL;

	switch_thread_rwlock_rdlock(gcache.shutdown_lock);
	*started = 1;

	// process prefetch requests
	while (!gcache.shutdown) {
		if (switch_queue_pop(gcache.prefetch_queue, &url) == SWITCH_STATUS_SUCCESS) {
			switch_stream_handle_t stream = { 0 };
			SWITCH_STANDARD_STREAM(stream);
			switch_api_execute("http_get", url, NULL, &stream);
			switch_safe_free(stream.data);
			switch_safe_free(url);
		}
		url = NULL;
	}

	// shutting down- clear the queue
	while (switch_queue_trypop(gcache.prefetch_queue, &url) == SWITCH_STATUS_SUCCESS) {
		switch_safe_free(url);
		url = NULL;
	}

	switch_thread_rwlock_unlock(gcache.shutdown_lock);

	return NULL;
}

/**
 * Configure the module
 * @param cache to configure
 * @return SWITCH_STATUS_SUCCESS if successful
 */
static switch_status_t do_config(url_cache_t *cache)
{
	char *cf = "http_cache.conf";
	switch_xml_t cfg, xml, param, settings, profiles;
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	int max_urls;
	switch_time_t default_max_age_sec;

	if (!(xml = switch_xml_open_cfg(cf, &cfg, NULL))) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "open of %s failed\n", cf);
		return SWITCH_STATUS_TERM;
	}

	/* set default config */
	max_urls = 4000;
	default_max_age_sec = 86400;
	cache->location = switch_core_sprintf(cache->pool, "%s%s", SWITCH_GLOBAL_dirs.base_dir, "/http_cache");
	cache->prefetch_queue_size = 100;
	cache->prefetch_thread_count = 8;
	cache->ssl_cacert = switch_core_sprintf(cache->pool, "%s%s", SWITCH_GLOBAL_dirs.certs_dir, "/cacert.pem");
	cache->ssl_verifyhost = 1;
	cache->ssl_verifypeer = 1;
	cache->enable_file_formats = 0;
	cache->connect_timeout = 300;
	cache->download_timeout = 300;

	/* get params */
	settings = switch_xml_child(cfg, "settings");
	if (settings) {
		for (param = switch_xml_child(settings, "param"); param; param = param->next) {
			char *var = (char *) switch_xml_attr_soft(param, "name");
			char *val = (char *) switch_xml_attr_soft(param, "value");
			if (!strcasecmp(var, "enable-file-formats")) {
				cache->enable_file_formats = switch_true(val);
				if (cache->enable_file_formats) {
					switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_NOTICE, "Enabling http:// and https:// formats.  This is unstable if mod_httapi is also loaded\n");
				}
			} else if (!strcasecmp(var, "max-urls")) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting max-urls to %s\n", val);
				max_urls = atoi(val);
			} else if (!strcasecmp(var, "location")) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting location to %s\n", val);
				cache->location = switch_core_strdup(cache->pool, val);
			} else if (!strcasecmp(var, "default-max-age")) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting default-max-age to %s\n", val);
				default_max_age_sec = atoi(val);
			} else if (!strcasecmp(var, "prefetch-queue-size")) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting prefetch-queue-size to %s\n", val);
				cache->prefetch_queue_size = atoi(val);
			} else if (!strcasecmp(var, "prefetch-thread-count")) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting prefetch-thread-count to %s\n", val);
				cache->prefetch_thread_count = atoi(val);
			} else if (!strcasecmp(var, "ssl-cacert")) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting ssl-cacert to %s\n", val);
				cache->ssl_cacert = switch_core_strdup(cache->pool, val);
			} else if (!strcasecmp(var, "ssl-verifyhost")) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting ssl-verifyhost to %s\n", val);
				cache->ssl_verifyhost = !switch_false(val); /* only disable if explicitly set to false */
			} else if (!strcasecmp(var, "ssl-verifypeer")) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting ssl-verifypeer to %s\n", val);
				cache->ssl_verifypeer = !switch_false(val); /* only disable if explicitly set to false */
			} else if (!strcasecmp(var, "connect-timeout")) {
				int int_val = atoi(val);
				if (int_val > 0) {
					switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting connect-timeout to %s\n", val);
					cache->connect_timeout = int_val;
				}
			} else if (!strcasecmp(var, "download-timeout")) {
				int int_val = atoi(val);
				if (int_val > 0) {
					switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Setting download-timeout to %s\n", val);
					cache->download_timeout = int_val;
				}
			} else {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Unsupported param: %s\n", var);
			}
		}
	}

	/* get profiles */
	profiles = switch_xml_child(cfg, "profiles");
	if (profiles) {
		switch_xml_t profile;
		for (profile = switch_xml_child(profiles, "profile"); profile; profile = profile->next) {
			const char *name = switch_xml_attr_soft(profile, "name");
			if (!zstr(name)) {
				http_profile_t *profile_obj = switch_core_alloc(cache->pool, sizeof(*profile_obj));
				switch_xml_t profile_xml;
				switch_xml_t domains;

				switch_strdup(profile_obj->name, name);
				profile_obj->aws_s3_access_key_id = NULL;
				profile_obj->secret_access_key = NULL;
				profile_obj->base_domain = NULL;
				profile_obj->bytes_per_block = 0;
				profile_obj->append_headers_ptr = NULL;
				profile_obj->finalise_put_ptr = NULL;

				profile_xml = switch_xml_child(profile, "aws-s3");
				if (profile_xml) {
					if (aws_s3_config_profile(profile_xml, profile_obj) == SWITCH_STATUS_FALSE) {
						continue;
					}
				} else {
					profile_xml = switch_xml_child(profile, "azure-blob");
					if (profile_xml) {
						if (azure_blob_config_profile(profile_xml, profile_obj) == SWITCH_STATUS_FALSE) {
							continue;
						}
					}
				}

				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Adding profile \"%s\" to cache\n", name);
				switch_core_hash_insert(cache->profiles, profile_obj->name, profile_obj);

				domains = switch_xml_child(profile, "domains");
				if (domains) {
					switch_xml_t domain;
					for (domain = switch_xml_child(domains, "domain"); domain; domain = domain->next) {
						const char *fqdn = switch_xml_attr_soft(domain, "name");
						if (!zstr(fqdn)) {
							switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO, "Adding profile \"%s\" domain \"%s\" to cache\n", name, fqdn);
							switch_core_hash_insert(cache->fqdn_profiles, fqdn, profile_obj);
						} else {
							switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "HTTP profile domain missing name!\n");
						}
					}
				}
			} else {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "HTTP profile missing name\n");
			}
		}
	}

	/* check config */
	if (max_urls <= 0) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "max-urls must be > 0\n");
		status = SWITCH_STATUS_TERM;
		goto done;
	}
	if (zstr(cache->location)) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "location must not be empty\n");
		status = SWITCH_STATUS_TERM;
		goto done;
	}
	if (default_max_age_sec <= 0) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "default-max-age must be > 0\n");
		status = SWITCH_STATUS_TERM;
		goto done;
	}
	if (cache->prefetch_queue_size <= 0) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "prefetch-queue-size must be > 0\n");
		status = SWITCH_STATUS_TERM;
		goto done;
	}
	if (cache->prefetch_thread_count <= 0) {
		switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "prefetch-thread-count must be > 0\n");
		status = SWITCH_STATUS_TERM;
		goto done;
	}

	cache->max_url = max_urls;
	cache->default_max_age = (default_max_age_sec * 1000 * 1000); /* convert from seconds to nanoseconds */
done:
	switch_xml_free(xml);

	return status;
}

/**
 * HTTP file playback state
 */
struct http_context {
	switch_file_handle_t fh;
	http_profile_t *profile;
	char *local_path;
	const char *write_url;
};

/**
 * Open URL
 * @param handle
 * @param path the URL
 * @return SWITCH_STATUS_SUCCESS if opened
 */
static switch_status_t http_cache_file_open(switch_file_handle_t *handle, const char *path)
{
	switch_status_t status = SWITCH_STATUS_SUCCESS;
	struct http_context *context = switch_core_alloc(handle->memory_pool, sizeof(*context));
	int file_flags = SWITCH_FILE_DATA_SHORT | (switch_test_flag(handle, SWITCH_FILE_FLAG_VIDEO) ? SWITCH_FILE_FLAG_VIDEO : 0);

	if (handle->params) {
		context->profile = url_cache_http_profile_find(&gcache, switch_event_get_header(handle->params, "profile"));
	}

	if (switch_test_flag(handle, SWITCH_FILE_FLAG_WRITE)) {
		/* WRITE = HTTP PUT */
		file_flags |= SWITCH_FILE_FLAG_WRITE;
		context->write_url = switch_core_strdup(handle->memory_pool, path);
		/* allocate local file in cache */
		context->local_path = cached_url_filename_create(&gcache, context->write_url, NULL);
	} else {
		/* READ = HTTP GET */
		file_flags |= SWITCH_FILE_FLAG_READ;
		context->local_path = url_cache_get(&gcache, context->profile, NULL, path, 1, handle->params ? switch_true(switch_event_get_header(handle->params, "refresh")) : 0, handle->memory_pool);
		if (!context->local_path) {
			return SWITCH_STATUS_FALSE;
		}
	}

	if ((status = switch_core_file_open(&context->fh,
			context->local_path,
			handle->channels,
			handle->samplerate,
			file_flags, NULL)) != SWITCH_STATUS_SUCCESS) {
			switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_ERROR, "Failed to open HTTP cache file: %s, %s\n", context->local_path, path);
			if (switch_test_flag(handle, SWITCH_FILE_FLAG_WRITE)) {
				switch_safe_free(context->local_path);
			}
			return status;
	}

	handle->private_info = context;
	handle->samples = context->fh.samples;
	handle->format = context->fh.format;
	handle->sections = context->fh.sections;
	handle->seekable = context->fh.seekable;
	handle->speed = context->fh.speed;
	handle->interval = context->fh.interval;
	handle->channels = context->fh.channels;
	handle->flags |= SWITCH_FILE_NOMUX;

	if (switch_test_flag((&context->fh), SWITCH_FILE_NATIVE)) {
		switch_set_flag_locked(handle, SWITCH_FILE_NATIVE);
	} else {
		switch_clear_flag_locked(handle, SWITCH_FILE_NATIVE);
	}

	if (switch_test_flag(&context->fh, SWITCH_FILE_FLAG_VIDEO)) {
		switch_set_flag_locked(handle, SWITCH_FILE_FLAG_VIDEO);
	} else {
		switch_clear_flag_locked(handle, SWITCH_FILE_FLAG_VIDEO);
	}

	return status;
}

/**
 * Open HTTP URL
 * @param handle
 * @param path the URL
 * @return SWITCH_STATUS_SUCCESS if opened
 */
static switch_status_t http_file_open(switch_file_handle_t *handle, const char *path)
{
	return http_cache_file_open(handle, switch_core_sprintf(handle->memory_pool, "http://%s", path));
}

/**
 * Open HTTPS URL
 * @param handle
 * @param path the URL
 * @return SWITCH_STATUS_SUCCESS if opened
 */
static switch_status_t https_file_open(switch_file_handle_t *handle, const char *path)
{
	return http_cache_file_open(handle, switch_core_sprintf(handle->memory_pool, "https://%s", path));
}

/**
 * Read from HTTP file
 * @param handle
 * @param data
 * @param len
 * @return
 */
static switch_status_t http_file_read(switch_file_handle_t *handle, void *data, size_t *len)
{
	struct http_context *context = (struct http_context *)handle->private_info;
	return switch_core_file_read(&context->fh, data, len);
}

/**
 * Write to HTTP file
 * @param handle
 * @param data
 * @param len
 * @return
 */
static switch_status_t http_file_write(switch_file_handle_t *handle, void *data, size_t *len)
{
	struct http_context *context = (struct http_context *)handle->private_info;
	return switch_core_file_write(&context->fh, data, len);
}

/**
 * Read from HTTP video file
 * @param handle
 * @param frame
 * @return
 */
static switch_status_t http_file_read_video(switch_file_handle_t *handle, switch_frame_t *frame, switch_video_read_flag_t flags)
{
	struct http_context *context = (struct http_context *)handle->private_info;
	return switch_core_file_read_video(&context->fh, frame, flags);
}

/**
 * Write to HTTP video file
 * @param handle
 * @param frame
 * @return
 */
static switch_status_t http_file_write_video(switch_file_handle_t *handle, switch_frame_t *frame)
{
	struct http_context *context = (struct http_context *)handle->private_info;
	return switch_core_file_write_video(&context->fh, frame);
}

/**
 * Close HTTP file
 * @param handle
 * @return SWITCH_STATUS_SUCCESS
 */
static switch_status_t http_file_close(switch_file_handle_t *handle)
{
	struct http_context *context = (struct http_context *)handle->private_info;
	switch_status_t status = switch_core_file_close(&context->fh);
	long httpRes = 0;

	if (status == SWITCH_STATUS_SUCCESS && !zstr(context->write_url)) {
		status = http_put(&gcache, context->profile, NULL, context->write_url, context->local_path, 1, &httpRes);
	}
	if (!zstr(context->write_url)) {
		switch_safe_free(context->local_path);
	}
	return status;
}

static char *http_supported_formats[] = { "http", NULL };
static char *https_supported_formats[] = { "https", NULL };
static char *http_cache_supported_formats[] = { "http_cache", NULL };

/**
 * Called when FreeSWITCH loads the module
 */
SWITCH_MODULE_LOAD_FUNCTION(mod_http_cache_load)
{
	switch_api_interface_t *api;
	int i;
	switch_file_interface_t *file_interface;

	*module_interface = switch_loadable_module_create_module_interface(pool, modname);

	SWITCH_ADD_API(api, "http_get", "HTTP GET", http_cache_get, HTTP_GET_SYNTAX);
	SWITCH_ADD_API(api, "http_tryget", "HTTP GET from cache only", http_cache_tryget, HTTP_GET_SYNTAX);
	SWITCH_ADD_API(api, "http_put", "HTTP PUT", http_cache_put, HTTP_PUT_SYNTAX);
	SWITCH_ADD_API(api, "http_clear_cache", "Clear the cache", http_cache_clear, HTTP_CACHE_CLEAR_SYNTAX);
	SWITCH_ADD_API(api, "http_remove_cache", "Remove URL from cache", http_cache_remove, HTTP_CACHE_REMOVE_SYNTAX);
	SWITCH_ADD_API(api, "http_prefetch", "Prefetch document in a background thread.  Use http_get to get the prefetched document", http_cache_prefetch, HTTP_PREFETCH_SYNTAX);

	memset(&gcache, 0, sizeof(url_cache_t));
	gcache.pool = pool;
	switch_core_hash_init(&gcache.map);
	switch_core_hash_init(&gcache.profiles);
	switch_core_hash_init_nocase(&gcache.fqdn_profiles);
	switch_mutex_init(&gcache.mutex, SWITCH_MUTEX_UNNESTED, gcache.pool);
	switch_thread_rwlock_create(&gcache.shutdown_lock, gcache.pool);

	if (do_config(&gcache) != SWITCH_STATUS_SUCCESS) {
		return SWITCH_STATUS_TERM;
	}

	file_interface = switch_loadable_module_create_interface(*module_interface, SWITCH_FILE_INTERFACE);
	file_interface->interface_name = modname;
	file_interface->extens = http_cache_supported_formats;
	file_interface->file_open = http_cache_file_open;
	file_interface->file_close = http_file_close;
	file_interface->file_read = http_file_read;
	file_interface->file_write = http_file_write;
	file_interface->file_read_video = http_file_read_video;
	file_interface->file_write_video = http_file_write_video;

	if (gcache.enable_file_formats) {
		file_interface = switch_loadable_module_create_interface(*module_interface, SWITCH_FILE_INTERFACE);
		file_interface->interface_name = modname;
		file_interface->extens = http_supported_formats;
		file_interface->file_open = http_file_open;
		file_interface->file_close = http_file_close;
		file_interface->file_read = http_file_read;
		file_interface->file_write = http_file_write;
		file_interface->file_read_video = http_file_read_video;
		file_interface->file_write_video = http_file_write_video;

		file_interface = switch_loadable_module_create_interface(*module_interface, SWITCH_FILE_INTERFACE);
		file_interface->interface_name = modname;
		file_interface->extens = https_supported_formats;
		file_interface->file_open = https_file_open;
		file_interface->file_close = http_file_close;
		file_interface->file_read = http_file_read;
		file_interface->file_write = http_file_write;
		file_interface->file_read_video = http_file_read_video;
		file_interface->file_write_video = http_file_write_video;
	}

	/* create the queue from configuration */
	gcache.queue.max_size = gcache.max_url;
	gcache.queue.data = switch_core_alloc(gcache.pool, sizeof(void *) * gcache.queue.max_size);
	gcache.queue.pos = 0;
	gcache.queue.size = 0;

	setup_dir(&gcache);

	/* Start the prefetch threads */
	switch_queue_create(&gcache.prefetch_queue, gcache.prefetch_queue_size, gcache.pool);
	for (i = 0; i < gcache.prefetch_thread_count; i++) {
		int started = 0;
		switch_thread_t *thread;
		switch_threadattr_t *thd_attr = NULL;
		switch_threadattr_create(&thd_attr, gcache.pool);
		switch_threadattr_detach_set(thd_attr, 1);
		switch_threadattr_stacksize_set(thd_attr, SWITCH_THREAD_STACKSIZE);
		switch_thread_create(&thread, thd_attr, prefetch_thread, &started, gcache.pool);
		while (!started) {
			switch_sleep(1000);
		}
	}

	/* indicate that the module should continue to be loaded */
	return SWITCH_STATUS_SUCCESS;
}

/**
 * Called when FreeSWITCH stops the module
 */
SWITCH_MODULE_SHUTDOWN_FUNCTION(mod_http_cache_shutdown)
{
	gcache.shutdown = 1;
	switch_queue_interrupt_all(gcache.prefetch_queue);
	switch_thread_rwlock_wrlock(gcache.shutdown_lock);
	switch_thread_rwlock_unlock(gcache.shutdown_lock);

	url_cache_clear(&gcache, NULL);
	switch_core_hash_destroy(&gcache.map);
	switch_core_hash_destroy(&gcache.profiles);
	switch_core_hash_destroy(&gcache.fqdn_profiles);
	switch_mutex_destroy(gcache.mutex);
	return SWITCH_STATUS_SUCCESS;
}


/* For Emacs:
 * Local Variables:
 * mode:c
 * indent-tabs-mode:t
 * tab-width:4
 * c-basic-offset:4
 * End:
 * For VIM:
 * vim:set softtabstop=4 shiftwidth=4 tabstop=4 noet:
 */
