Add. Support sound prompts on call flow. (#1645)

This file uses new way to load recordings from DB.

resources/install/scripts/resources/functions/file.lua

@@ -0,0 +1,57 @@
+-- load base64 if exists
+	pcall(require, "resources.functions.base64")
+
+-- load logger for file library
+	local log = require "resources.functions.log".file
+
+local base64 = base64
+
+local function write_file(fname, data, mode)
+	local file, err = io.open(fname, mode or "wb")
+	if not file then
+		log.err("Can not open file to write:" .. tostring(err))
+		return nil, err
+	end
+	file:write(data)
+	file:close()
+	return true
+end
+
+-- decode and write to file
+local function write_base64(fname, encoded, mode)
+	return write_file(fname, base64.decode(encoded), mode)
+end
+
+local function read_file(fname, mode)
+	local file, err = io.open(fname, mode or "rb")
+	if not file then
+		log.err("Can not open file to read:" .. tostring(err))
+		return nil, err
+	end
+	local data = file:read("*all")
+	file:close()
+	return data
+end
+
+-- read file and encode
+local function read_base64(fname, mode)
+	local data, err = read_file(fname, mode)
+	if not data then return nil, err end
+	return base64.encode(data)
+end
+
+local function file_exists(name)
+	local f = io.open(name, "r")
+	if not f then return end
+	f:close()
+	return name
+end
+
+return {
+	read         = read_file;
+	read_base64  = read_base64;
+	write        = write_file;
+	write_base64 = write_base64;
+	exists       = file_exists;
+	remove       = os.remove;
+}