module (..., package.seeall)

-- Load libraries
require("modelfunctions")
require("posix")
require("fs")
require("format")
require("validator")
require("luasql.sqlite3")
require("session")

-- Set variables
local configfile = "/etc/freeswitchvmail.conf"
local configcontent = fs.read_file(configfile) or ""
local config = format.parse_ini_file(configcontent, "") or {}
config.database = config.database or "/var/lib/freeswitch/db/voicemail_default.db"
config.domain = config.domain or "voicemail"
config.event_socket_ip = config.event_socket_ip or "127.0.0.1"
config.event_socket_port = config.event_socket_port or "8021"
config.event_socket_password = config.event_socket_password or "ClueCon"
local env
local con

local voicemail_users_creation_script = {
	"CREATE TABLE voicemail_users (username VARCHAR(255))",
}

local voicemail_values_creation_script = {
	"CREATE TABLE voicemail_values (username VARCHAR(255), name VARCHAR(255), value VARCHAR(255))",
}

local voicemail_params_creation_script = {
	"CREATE TABLE voicemail_params (name VARCHAR(255) primary key, type VARCHAR(255), label VARCHAR(255), descr VARCHAR(255), value VARCHAR(255))",
	"INSERT INTO voicemail_params VALUES('username', 'text', 'Extension', '', '')",
	"INSERT INTO voicemail_params VALUES('firstname', 'text', 'User First Name', '', '')",
	"INSERT INTO voicemail_params VALUES('lastname', 'text', 'User Last Name', '', '')",
	"INSERT INTO voicemail_params VALUES('vm-password', 'text', 'Voicemail Password', '', '')",
	"INSERT INTO voicemail_params VALUES('vm-password-confirm', 'text', 'Enter again to confirm', '', '')",
	"INSERT INTO voicemail_params VALUES('vm-mailto', 'text', 'Email Address', 'Email a notification, including audio file if enabled', '')",
	"INSERT INTO voicemail_params VALUES('vm-email-all-messages', 'boolean', 'Email Enable', '', 'false')",
	"INSERT INTO voicemail_params VALUES('vm-attach-file', 'boolean', 'Attach voicemail to email', 'Option to attach audio file to email', 'false')",
	"INSERT INTO voicemail_params VALUES('vm-keep-local-after-email', 'boolean', 'Keep voicemail after emailed', 'When disabled the message will be deleted from the voicemailbox after the notification email is sent. This allows receiving voicemail via email alone, rather than having the voicemail available from the Web interface or by telephone. CAUTION: Attach voicemail to email must be enabled, OTHERWISE YOUR MESSAGES WILL BE LOST FOREVER.', 'true')",
	"INSERT INTO voicemail_params VALUES('vm-notify-mailto', 'text', 'Pager Email Address', 'Email a short notification', '')",
	"INSERT INTO voicemail_params VALUES('vm-notify-email-all-messages', 'boolean', 'Pager Email Enable', '', 'false')",
}

local voicemail_folders_creation_script = {
	"CREATE TABLE voicemail_folders (in_folder VARCHAR(255) primary key, label VARCHAR(255))",
	"INSERT INTO voicemail_folders VALUES('inbox', 'Inbox')",
}

local voicemail_prefs_creation_script = {"CREATE TABLE voicemail_prefs (username VARCHAR(255), domain VARCHAR(255), name_path VARCHAR(255), greeting_path VARCHAR(255), password VARCHAR(255))"}

-- ################################################################################
-- LOCAL FUNCTIONS
local function escape_quotes(str)
	return string.gsub(str or "", "'", "'\\''")
end

local function voicemail_inject(user, domain, sound_file, cid_num, cid_name)
	local cmd = "echo -e 'auth "..escape_quotes(config.event_socket_password).."\n\n"
	cmd = cmd.."api voicemail_inject "..escape_quotes(user).."@"..escape_quotes(domain).." "..escape_quotes(sound_file).." "..escape_quotes(cid_num).." "..string.gsub(escape_quotes(cid_name), " ", "%%20")
	cmd = cmd.."\n\nexit\n\n' | nc "..format.escapespecialcharacters(config.event_socket_ip).." "..format.escapespecialcharacters(config.event_socket_port).." 2>&1"
	local f = io.popen( cmd )
	local result = f:read("*a") or ""
	f:close()
	return result
end

local function assert (v, m)
	if not v then
		m = m or "Assertion failed!"
		error(m, 0)
	end
	return v, m
end

-- Escape special characters in sql statements
local escape = function(sql)
	sql = sql or ""
	sql = string.gsub(sql, "'", "''")
	return string.gsub(sql, "\\", "\\\\")
end

local databaseconnect = function()
	if not con then
		-- create environment object
		env = assert (luasql.sqlite3())
		-- connect to data source
		con = assert (env:connect(config.database))
		return true
	end
	return false
end

local databasedisconnect = function()
	if env then
		env:close()
		env = nil
	end
	if con then
		con:close()
		con = nil
	end
end

local runscript = function(script)
	for i,scr in ipairs(script) do
		logevent(scr)
		assert( con:execute(scr) )
	end
end

local checktable = function(table)
	local success = false
	local errtxt
        local res, err = pcall(function()
		local sql = "SELECT * FROM "..table.." LIMIT 1"
		local cur = assert (con:execute(sql))
		cur:close()
		success = true
	end)
	if not res and err then
		errtxt = err
	end
	return success, errtxt
end

local getselectresponse = function(sql)
	local retval = {}
	local cur = assert (con:execute(sql))
	local row = cur:fetch ({}, "a")
	while row do
		local tmp = {}
		for name,val in pairs(row) do
			tmp[name] = val
		end
		retval[#retval + 1] = tmp
		row = cur:fetch (row, "a")
	end
	cur:close()
	return retval
end

local generatewhereclause = function(username, message, foldername)
        local sql = ""
	local where = {}
	if username and username ~= "" then
		where[#where+1] = "username = '"..escape(username).."'"
	end
	if message and type(message) == "string" and message ~= "" then
		where[#where+1] = "uuid = '"..escape(message).."'"
	elseif message and type(message) == "table" and #message > 0 then
		local where2 = {}
		for i,m in ipairs(message) do
			where2[#where2+1] = "uuid = '"..escape(m).."'"
		end
		where[#where+1] = "(" .. table.concat(where2, " OR ") .. ")"
	end
	if foldername and foldername ~= "" then
		where[#where+1] = "in_folder = '"..escape(foldername).."'"
	end
	if #where > 0 then
		sql = " WHERE " .. table.concat(where, " AND ")
	end
	return sql
end

-- These funtions access the new voicemail tables added for ACF

local listfolders = function(foldername)
	if not checktable("voicemail_folders") then runscript(voicemail_folders_creation_script) end
	local sql = "SELECT * FROM voicemail_folders" .. generatewhereclause(nil, nil, foldername).." ORDER BY label"
	return getselectresponse(sql)
end

local validfolder = function(foldername)
	return foldername and (foldername ~= "") and (#listfolders(foldername) > 0)
end

local listusers = function(username)
	if not checktable("voicemail_users") then runscript(voicemail_users_creation_script) end
	local sql = "SELECT * FROM voicemail_users" .. generatewhereclause(username).." ORDER BY username"
	return getselectresponse(sql)
end

local validuser = function(username)
	return username and (username ~= "") and (#listusers(username) > 0)
end

local getuserparams = function(username)
	local retval = {}
	if not checktable("voicemail_params") then runscript(voicemail_params_creation_script) end
	local sql = "SELECT * FROM voicemail_params"
	local params = getselectresponse(sql)
	for i,parm in ipairs(params) do
		if parm.name then
			retval[parm.name] = {}
			for n,v in pairs(parm) do
				retval[parm.name][n] = v
			end
			if retval[parm.name].type == "boolean" then
				retval[parm.name].value = (retval[parm.name].value == "true")
			end
		end
	end
	if retval.username and username then retval.username.value = username end
	if validuser(username) then
		-- Get password from voicemail_prefs (don't fail for missing table)
		if checktable("voicemail_prefs") then
			local sql = "SELECT password FROM voicemail_prefs"..generatewhereclause(username)
			local password = getselectresponse(sql)
			if retval["vm-password"] and password[1] then
				retval["vm-password"].value = password[1].password
			end
		end

		-- Get other parameters from voicemail_values
		if not checktable("voicemail_values") then runscript(voicemail_values_creation_script) end
		sql = "SELECT * FROM voicemail_values"..generatewhereclause(username)
		local params = getselectresponse(sql)
		for i,param in ipairs(params) do
			if param.name and retval[param.name] and param.value then
				if retval[param.name].type == "boolean" then
					param.value = (param.value == "true")
				end
				retval[param.name].value = param.value
			end
		end
	end
	return retval
end

local setuserparams = function(userparams)
	if not userparams.username or not userparams.username.value or not validuser(userparams.username.value) then
		return false, "Invalid User"
	end
	local success = true
	if not checktable("voicemail_params") then runscript(voicemail_params_creation_script) end
	local sql = "SELECT * FROM voicemail_params"
	local params = getselectresponse(sql)
	-- There are a few params not to put in the voicemail_values table
	if not checktable("voicemail_values") then runscript(voicemail_values_creation_script) end
	local ignoreparam = { username=true, ["vm-password"]=true, ["vm-password-confirm"]=true }
	con:execute("START TRANSACTION")
	for i,parm in ipairs(params) do
		if parm.name and not ignoreparam[parm.name] then
			sql = "DELETE FROM voicemail_values"..generatewhereclause(userparams.username.value).." and name='"..parm.name.."'"
			assert( con:execute(sql) )
			if userparams[parm.name] and (userparams[parm.name].value ~= nil) and tostring(userparams[parm.name].value) ~= parm.value then
				sql = "INSERT INTO voicemail_values VALUES('"..userparams.username.value.."', '"..parm.name.."', '"..tostring(userparams[parm.name].value).."')"
				assert( con:execute(sql) )
			end
		end
	end
	-- Set password to voicemail_prefs
	if userparams["vm-password"] and userparams["vm-password"].value and userparams["vm-password"].value ~= "" then
		if not checktable("voicemail_prefs") then runscript(voicemail_prefs_creation_script) end
		sql = "SELECT password FROM voicemail_prefs"..generatewhereclause(userparams.username.value)
		local password = getselectresponse(sql)
		if #password > 0 then
			-- update
			sql = "UPDATE voicemail_prefs SET password='"..userparams["vm-password"].value.."'"..generatewhereclause(userparams.username.value)
		else
			-- insert
			sql = "INSERT INTO voicemail_prefs (username, domain, password) VALUES ('"..userparams.username.value.."', '"..config.domain.."', '"..userparams["vm-password"].value.."')"
		end
		assert( con:execute(sql) )
	end
	con:execute("COMMIT")
	return success
end

local function validateconfig(newconfig)
	local success = true
	if newconfig.value.domain.value == "" then
		newconfig.value.domain.errtxt = "Cannot be blank"
		success = false
	end
	if newconfig.value.database.value == "" then
		newconfig.value.database.errtxt = "Cannot be blank"
		success = false
	end
	if newconfig.value.event_socket_ip.value == "" then
		newconfig.value.event_socket_ip.errtxt = "Cannot be blank"
		success = false
	end
	if newconfig.value.event_socket_port.value == "" then
		newconfig.value.event_socket_port.errtxt = "Cannot be blank"
		success = false
	end
	if newconfig.value.event_socket_password.value == "" then
		newconfig.value.event_socket_password.errtxt = "Cannot be blank"
		success = false
	end
	return success, newconfig
end

-- ################################################################################
-- PUBLIC FUNCTIONS

get_config = function()
	local result = {}
	result.domain = cfe({ value=config.domain, label="Domain" })
	result.database = cfe({ value=config.database, label="Database" })
	result.event_socket_ip = cfe({ value=config.event_socket_ip, label="FS Event Socket IP" })
	result.event_socket_port = cfe({ value=config.event_socket_port, label="FS Event Socket Port" })
	result.event_socket_password = cfe({ value=config.event_socket_password, label="FS Event Socket Password" })
	return cfe({ type="group", value=result, label="Voicemail Config" })
end

update_config = function(newconfig)
	local success = validateconfig(newconfig)
	if success then
		for name,val in pairs(newconfig.value) do
			configcontent = format.update_ini_file(configcontent, "", name, tostring(val.value))
		end

		fs.write_file(configfile, configcontent)
		config = format.parse_ini_file(configcontent, "") or {}
	else
		newconfig.errtxt = "Failed to update config"
	end

	return newconfig
end

list_messages = function(username)
	local retval = {}
	local errtxt
        local res, err = pcall(function()
		local connected = databaseconnect()
		local sql = "SELECT * FROM voicemail_msgs"
		sql = sql .. generatewhereclause(username)
		sql = sql .. " ORDER BY username ASC, created_epoch ASC"
		retval = getselectresponse(sql)
		if connected then databasedisconnect() end
	end)
	if not res and err then
		errtxt = err
	end
	return cfe({ type="structure", value=retval, label="List of Messages", errtxt=errtxt })
end

get_message = function(message, username)
	local retval = cfe({ type="raw", label="error", option="audio/x-wav" })
        local res, err = pcall(function()
		local connected = databaseconnect()
		local sql = "SELECT file_path FROM voicemail_msgs"
		sql = sql .. generatewhereclause(username, message)
		local tmp = getselectresponse(sql)
		if connected then databasedisconnect() end
		if #tmp == 0 then
			retval.errtxt = "Invalid message"
		else
			retval.label = posix.basename(tmp[1].file_path)
			retval.value = fs.read_file(tmp[1].file_path)
			retval.length = #retval.value
		end
	end)
	if not res and err then
		retval.errtxt = err
	end
	return retval
end

delete_message = function(message, username)
	local retval = cfe({ label="Delete message result", errtxt="Failed to delete message - message not found" })
	local messages = format.string_to_table(message, "%s*,%s*")
        local res, err = pcall(function()
		local connected = databaseconnect()
		local sql = "SELECT * FROM voicemail_msgs"
		sql = sql .. generatewhereclause(username, messages)
		local tmp = getselectresponse(sql)
		if #tmp == #messages then
			sql = "DELETE FROM voicemail_msgs" .. generatewhereclause(username, messages)
			assert (con:execute(sql))
			for i,t in ipairs(tmp) do
				os.remove(t.file_path)
			end
			if #messages == 1 then
				retval.value = "Deleted message"
			else
				retval.value = "Deleted "..#messages.." messages"
			end
			retval.errtxt = nil
		end
		if connected then databasedisconnect() end
	end)
	if not res and err then
		retval.errtxt = err
	end

	return retval
end

forward_message = function(message, newuser, username)
	local retval = cfe({ label="Forward message result" })
	local messages = format.string_to_table(message, "%s*,%s*")
        local res, err = pcall(function()
		local connected = databaseconnect()
		-- Check if message exists
		local sql = "SELECT * FROM voicemail_msgs" .. generatewhereclause(username, messages)
		local mess = getselectresponse(sql)
		if #mess == #messages then
			-- Check if newuser exists
			if validuser(newuser) then
				for i,m in ipairs(mess) do
					-- Forward message using mod_voicemail API
					-- doesn't seem like there's any way to tell whether or not it worked
					voicemail_inject(newuser, config.domain, m.file_path, m.cid_number, m.cid_name)
				end
				if #mess == 1 then
					retval.value = "Forwarded message"
				else
					retval.value = "Forwarded "..#mess.." messages"
				end
			else
				retval.errtxt = "Failed to forward message - invalid user"
			end
		else
			retval.errtxt = "Failed to forward message - message not found"
		end
		if connected then databasedisconnect() end
	end)
	if not res and err then
		retval.errtxt = err
	end

	return retval
end

email_message = function(message, address, username)
	local retval = cfe({ label="E-mail message result" })
	local messages = format.string_to_table(message, "%s*,%s*")
        local res, err = pcall(function()
		local connected = databaseconnect()
		-- Check if message exists
		local sql = "SELECT * FROM voicemail_msgs" .. generatewhereclause(username, messages)
		local mess = getselectresponse(sql)
		if #mess == #messages then
			-- Create a temporary user and settings
			local newuser = "tempuser"..session.random_hash(128)
			while validuser(newuser) do
				newuser = "tempuser"..session.random_hash(128)
			end
			local settings = get_usersettings(newuser)
			if settings.value["vm-mailto"] and settings.value["vm-email-all-messages"] and settings.value["vm-attach-file"] and settings.value["vm-keep-local-after-email"] then
				settings.value["vm-mailto"].value = address
				settings.value["vm-email-all-messages"].value = true
				settings.value["vm-attach-file"].value = true
				settings.value["vm-keep-local-after-email"].value = false
				if settings.value["vm-password"] then settings.value["vm-password"].value = "1234" end
				if settings.value["vm-password-confirm"] then settings.value["vm-password-confirm"].value = "1234" end
				settings = create_usersettings(settings)
				if not settings.errtxt then
					for i,m in ipairs(mess) do
						-- E-mail message using mod_voicemail API
						-- doesn't seem like there's any way to tell whether or not it worked
						voicemail_inject(newuser, config.domain, m.file_path, m.cid_number, m.cid_name)
					end
					if #mess == 1 then
						retval.value = "E-mailed message"
					else
						retval.value = "E-mailed "..#mess.." messages"
					end
					-- Now, delete the temporary user
					delete_user(newuser)
				else
					retval.errtxt = "Failed to e-mail message - "..settings.errtxt
				end
			else
				retval.errtxt = "Failed to e-mail message - unsupported"
			end
		else
			retval.errtxt = "Failed to e-mail message - message not found"
		end
		if connected then databasedisconnect() end
	end)
	if not res and err then
		retval.errtxt = err
	end

	return retval
end

move_message = function(message, newfolder, username)
	local retval = cfe({ label="Move message result" })
	local messages = format.string_to_table(message, "%s*,%s*")
        local res, err = pcall(function()
		local connected = databaseconnect()
		-- Check if message exists
		local sql = "SELECT * FROM voicemail_msgs" .. generatewhereclause(username, messages)
		local mess = getselectresponse(sql)
		if #mess == #messages then
			-- Check if newfolder exists
			if validfolder(newfolder) then
				for i,m in ipairs(mess) do
					local sql = "UPDATE voicemail_msgs SET in_folder='"..newfolder.."'" .. generatewhereclause(username, messages)
					assert (con:execute(sql))
				end
				if #mess == 1 then
					retval.value = "Moved message"
				else
					retval.value = "Moved "..#mess.." messages"
				end
			else
				retval.errtxt = "Failed to move message - invalid folder"
			end
		else
			retval.errtxt = "Failed to move message - message not found"
		end
		if connected then databasedisconnect() end
	end)
	if not res and err then
		retval.errtxt = err
	end

	return retval
end

list_folders = function()
	local errtxt
	local folders = {}
        local res, err = pcall(function()
		local connected = databaseconnect()
		folders = listfolders()
		if connected then databasedisconnect() end
	end)
	if not res and err then
		errtxt = err
	end

	return cfe({ type="structure", value=folders, label="Voicemail Folders", errtxt=errtxt })
end

list_users = function()
	local errtxt
	local users = {}
        local res, err = pcall(function()
		local connected = databaseconnect()
		users = listusers()
		-- Go in reverse order to remove the temporary users used for e-mailing messages
		for i=#users,1,-1 do
			u = users[i]
			-- Remove the temporary users
			if string.find(u.username, "^tempuser") then
				table.remove(users, i)
			else
				local sql = "SELECT * FROM voicemail_values"..generatewhereclause(u.username).." and (name='firstname' or name='lastname')"
				local cur = con:execute(sql)
				local row = cur:fetch ({}, "a")
				while row do
					u[row.name] = row.value
					row = cur:fetch (row, "a")
				end
				cur:close()
			end
		end
		if connected then databasedisconnect() end
	end)
	if not res and err then
		errtxt = err
	end

	return cfe({ type="structure", value=users, label="Voicemail Users", errtxt=errtxt })
end

delete_user = function(username)
	local result = ""
	local errtxt
	errtxt = nil
       	local res, err = pcall(function()
		local connected = databaseconnect()
		local users = listusers(username)
		if #users == 0 then
			errtxt = "User does not exist"
		else
			-- Delete all of the user's voicemails
			local messages = list_messages(username)
			if #messages.value then
				for i,m in ipairs(messages.value) do
					delete_message(m.uuid)
				end
			end
			-- Remove the user parameters
			sql = "DELETE FROM voicemail_values " .. generatewhereclause(username)
			assert (con:execute(sql))
			-- Remove the user
			sql = "DELETE FROM voicemail_users " .. generatewhereclause(username)
			assert (con:execute(sql))
			result = "Voicemail User Deleted"
		end
		if connected then databasedisconnect() end
	end)
	if not res and err then
		errtxt = err
	end

	return cfe({ value=result, errtxt=errtxt, label="Delete User Result" })
end

get_usersettings = function(username)
	local retval = {}
	local errtxt
        local res, err = pcall(function()
		local connected = databaseconnect()
		retval = getuserparams(username)
		if connected then databasedisconnect() end
	end)
	if not res and err then
		errtxt = err
	end
	if retval["vm-password"] and retval["vm-password-confirm"] then retval["vm-password-confirm"].value = retval["vm-password"].value end

	return cfe({ type="group", value=retval, label="Voicemail User Settings", errtxt=errtxt })
end

create_usersettings = function(usersettings)
	return update_usersettings(usersettings, true)
end

update_usersettings = function(usersettings, create)
	local success = true
	local errtxt
	-- Validate the settings
	if not validator.is_integer(usersettings.value["vm-password"].value) then
		success = false
		usersettings.value["vm-password"].errtxt = "Password must be all numbers"
	end
	if usersettings.value["vm-password"].value ~= usersettings.value["vm-password-confirm"].value then
		success = false
		usersettings.value["vm-password-confirm"].errtxt = "Password does not match"
	end
	if success then
        	local res, err = pcall(function()
			local connected = databaseconnect()
			local u = listusers(usersettings.value.username.value)
			if create and #u > 0 then
				success = false
				errtxt = "User already exists"
			elseif not create and #u == 0 then
				success = false
				errtxt = "User does not exist"
			else
				if create then
					sql = "INSERT INTO voicemail_users VALUES('"..escape(usersettings.value.username.value).."')"
					assert (con:execute(sql))
				end
				success,errtxt = setuserparams(usersettings.value)
			end
			if connected then databasedisconnect() end
		end)
		if not res and err then
			success = false
			errtxt = err
		end
	end
	if not success then
		if create then
			usersettings.errtxt = errtxt or "Failed to create user"
		else
			usersettings.errtxt = errtxt or "Failed to save settings"
		end
	end
	return usersettings
end

process_directory_xml_request = function(input)
	local output = {}
	local errtxt
        local res, err = pcall(function()
		local connected = databaseconnect()
		if validuser(input.user) then
			output = getuserparams(input.user)
			-- Add the domain
			output.domain = cfe({ value=input.domain })
		else
			errtxt = "User not found"
		end
		if connected then databasedisconnect() end
	end)
	if not res and err then
		errtxt = err
	end
	return cfe({ type="group", value=output, label="Directory Data", errtxt=errtxt })
end

process_dialplan_xml_request = function(input)
	local output = {}
	local errtxt
        local res, err = pcall(function()
		local connected = databaseconnect()
		if validuser(input["Caller-Destination-Number"]) then
			output.domain = cfe({ value=config.domain })
			output.username = cfe({ value=input["Caller-Destination-Number"] })
		else
			errtxt = "User not found"
		end
		if connected then databasedisconnect() end
	end)
	if not res and err then
		errtxt = err
	end
	return cfe({ type="group", value=output, label="Dialplan Data", errtxt=errtxt })
end