#!/usr/bin/lua

package.cpath = package.cpath .. ";/usr/lib/lua/5.1/?.so"
local cjson = require("cjson")
-- local mtkwifi = require("mtkwifi")
-- local sys = require("luci.sys")
-- local uci = require("luci.model.uci").cursor()
-- local util = require("luci.util")
-- local devices = mtkwifi.get_all_devs()
local session_file = "/tmp/session_data.json"
local session_timeout = 900 -- Session timeout in seconds (15 minutes)
local SERVER = "https://device-api-stg.wicrypt.com"

-- Function to get device information
function IfDevicesInfo()
    local result = {}
    for _, device in ipairs(devices) do
        for _, vif in ipairs(device.vifs) do
            if vif.vifname == 'ra0' or vif.vifname == 'rai0' then
                table.insert(result, {
                    devname = device.devname,
                    vifs_prefix = device.vifs.__prefix,
                    ssid = vif.__ssid,
                    encrypttype = vif.__encrypttype,
                    authmode = vif.__authmode,
                    vifname = vif.vifname,
                    hidessid = vif.__hidessid,
                    vifidx = vif.vifidx,
                    wpapsk = vif.__wpapsk,
                    bssid = vif.__bssid
                })
            end
        end
    end
    return result
end

-- Function to compute HMAC-SHA256 using OpenSSL
function compute_hmac_sha256(key, message)
    local command = string.format('echo -n \'%s\' | openssl dgst -sha256 -hmac \'%s\' | awk \'{print $2}\'', message, key)
    local handle = io.popen(command)
    local result = handle:read("*a")
    handle:close()
    return result:match("^%s*(.-)%s*$") -- Trim any surrounding whitespace
end

function gen_rand_hash()
    local command = string.format('echo -n "$(date +%s%N)$(openssl rand -hex 8)" | md5sum | awk \'{print $1}\'')
    local handle = io.popen(command)
    local hash = handle:read("*a")
    handle:close()
    return hash
end

-- Function to read session data from file
function read_sessions()
    local file = io.open(session_file, "r")
    if not file then return {} end
    local content = file:read("*a")
    file:close()
    return cjson.decode(content) or {}
end

-- Function to write session data to file
function write_sessions(sessions)
    local file = io.open(session_file, "w")
    file:write(cjson.encode(sessions))
    file:close()
end

-- Function to retrieve session by session_id
function SessionRetrieve(session_id)
    local sessions = read_sessions()
    local session = sessions[session_id]

    if session then
        local current_time = os.time()
        if current_time - session.created_at > session_timeout then
            sessions[session_id] = nil
            write_sessions(sessions)
            return cjson.encode({ error = "Session expired", success = false, data = nil })
        end

        return cjson.encode({ data = session, success = true, error = nil })
    else
        return cjson.encode({ error = "Invalid Session", success = false, data = nil })
    end
end

function Login(pass)
    local cusor = io.open("/etc/wicrypt/database/config.json", "r")
    if cusor == nil then
        return cjson.encode({ data = {}, success = false, error = "Firmware server error" })
    end
    local content = cusor:read("*all")
    cusor:close()
    local configJson = cjson.decode(content)
    if not configJson then
        return cjson.encode({ data = {}, success = false, error = "Firmware server error" })
    end
    local devPhrase = configJson.devPhrase
    local storedHash = configJson.storedHash
    cusor:close()

    if devPhrase == '' and storedHash == '' then
        if pass == "admin" then
            local session_id = gen_rand_hash()
            local sessions = read_sessions()
            sessions[session_id] = { username = "wicrypt", token = gen_rand_hash(), created_at = os.time() }
            write_sessions(sessions)
            print("Set-Cookie: sessionId=" .. session_id .. "; Path=/; HttpOnly")
            print("\r\n")
            return SessionRetrieve(session_id)
        else
            print("\r\n")
            return cjson.encode({ error = "Wrong credentials", success = false, data = nil })
        end
    else
        -- Registered device login
        if devPhrase and storedHash then
            local computedHash = compute_hmac_sha256(devPhrase, pass)

            if computedHash == storedHash then
                local session_id = gen_rand_hash()
                local sessions = read_sessions()
                sessions[session_id] = { username = "wicrypt", token = gen_rand_hash(), created_at = os.time() }
                write_sessions(sessions)

                print("Set-Cookie: sessionId=" .. session_id .. "; Path=/; HttpOnly")
                print("\r\n")
                return SessionRetrieve(session_id)
            else
                print("\r\n")
                return cjson.encode({ error = "Wrong credentials", success = false, data = nil })
            end
        else
            print("\r\n")
            return cjson.encode({ error = "Device not registered", success = false, data = nil })
        end
    end
end

-- Function to clean up expired sessions (can be called periodically)
function CleanupExpiredSessions()
    local sessions = read_sessions()
    local current_time = os.time()
    local changed = false

    for session_id, session in pairs(sessions) do
        if current_time - session.created_at > session_timeout then
            sessions[session_id] = nil
            changed = true
        end
    end

    if changed then
        write_sessions(sessions)
    end
end

function BoardInfo()
    print("\r\n")
    local info = util.ubus("system", "board")
    return jsonc.stringify({ data = info, success = true, error = nil })
end

function FirmwEnable()
    print("\r\n")
    os.execute("/etc/init.d/spikeserviceprocd enable")
    local suc, exitCode, code = os.execute("/etc/init.d/spikeserviceprocd start")
    if suc then
        return jsonc.stringify({ message = "spikeserviceprocd started successfully", error = nil, success = true })
    else
        return jsonc.stringify({ error = "Failed to start spikeserviceprocd", message = nil, success = false })
    end
end

function FirmwDisable()
    print("\r\n")
    local suc, exitCode, code = os.execute("/etc/init.d/spikeserviceprocd disable")
    if suc then
        return jsonc.stringify({ message = "spikeserviceprocd disabled successfully", error = nil, success = true })
    else
        return jsonc.stringify({ error = "Failed to disable spikeserviceprocd", message = nil, success = false })
    end
end

function RegisterDevice(email, pin)
    print("\r\n")
    local mac = util.ubus("luci-rpc", "getNetworkDevices", {}).br0.mac
    local wireless = util.ubus("iwinfo", "info", { device = "ra0" })

    local brd_info = util.ubus("system", "board")

    local license = uci:get("wicrypt", "licence", "key")


    local body = jsonc.stringify({
        architecture = brd_info.system,
        bssid = wireless.bssid,
        deviceModel = brd_info.model,
        email = email,
        macAddress = mac,
        pin = pin,
        releaseVersion = "1.0.0",
        ssid = wireless.ssid
    })

    local curlCommand = string.format(
        'curl -s -X POST -H "Content-Type: application/json" -H "x-license-key: %s"  -d \'%s\' %s/api/v1/device',
        license,
        body, SERVER)
    local result = util.exec(curlCommand)
    return result
end

function RegStatus()
    print("\r\n")
    local ifInfo = IfDevicesInfo()
    local bssid = ifInfo[1].bssid
    local curlCommand = string.format(
        'curl -s -X GET -H encType="multipart/form-data" -d "" "%s/api/v1/device/status/%s"', SERVER, bssid)
    local result = util.exec(curlCommand)
    return result
end

function FirmwServiceStatus()
    print("\r\n")
    local spikeserviceprocd = util.ubus("luci", "getInitList", { name = "spikeserviceprocd" })
    if type(spikeserviceprocd) ~= "table" then
        return jsonc.stringify({ error = "Failed to get spikeserviceprocd status", success = false })
    end
    return jsonc.stringify(spikeserviceprocd)
end

function MemoryInfo()
    print("\r\n")
    local memory_info = util.ubus("system", "info")
    if type(memory_info) ~= "table" then
        return jsonc.stringify({ success = false, error = "Failed to get system info" })
    end
    return jsonc.stringify({ data = memory_info, success = true, error = nil })
end

function Wireless()
    print("\r\n")
    local wifis = IfDevicesInfo()
    return jsonc.stringify({ data = wifis, success = true, error = nil })
end

function transferSpeed()
    print("\r\n")
    local res = util.exec('vnstat -tr -i br0 --json')
    return jsonc.stringify({ data = jsonc.parse(res), success = true, error = nil })
end

function signalStrenght()
    print("\r\n")
    local res = util.exec('iwconfig ra0 | awk \'/Link Quality/ { print $2}\'    ')
    return jsonc.stringify({ data = res, success = true, error = nil })
end

function DhcpLease()
    print("\r\n")
    local cusor = io.open("/tmp/dnsmasq.leases", "r")
    if cusor == nil then
        return jsonc.stringify({ data = {}, success = false, error = "Failed to open dnsmasq.leases" })
    end
    local content = cusor:read("*all")
    cusor:close()
    local result = {}
    -- format the dhcp data to json
    for line in content:gmatch("[^\r\n]+") do
        local parts = {}
        for part in line:gmatch("%S+") do
            table.insert(parts, part)
        end

        local entry = {
            timestamp = tonumber(parts[1]),
            mac = parts[2],
            ip = parts[3],
            clientName = parts[4] == "*" and nil or parts[4],
            additionalMac = parts[5]
        }

        table.insert(result, entry)
    end
    return jsonc.stringify({ data = result, success = true, error = nil })
end

function WifiDevices()
    print("\r\n")
    local result = IfDevicesInfo()
    return jsonc.stringify({ data = result, success = true, error = nil })
end

function ChangeSsid(devname, newssid)
    print("\r\n")
    if devname == "5G" then
        util.exec("wc_wifi_config ssid5 " .. newssid)
    elseif devname == "2.4G" then
        util.exec("wc_wifi_config ssid2.4 " .. newssid)
    end
    return jsonc.stringify({ success = true, error = nil })
end

function ChangeWirelessAuthConfig(devname, authmode, key)
    print("\r\n")
    if devname == "5G" and key ~= nil then
        util.exec("wc_wifi_config pwd5 " .. key)
    end
    if devname == "2.4G" and key ~= nil then
        util.exec("wc_wifi_config pwd2.4 " .. key)
    end
    if devname == "5G" and authmode ~= nil then
        util.exec("wc_wifi_config enc5 " .. authmode)
    elseif devname == "2.4G" and authmode ~= nil then
        util.exec("wc_wifi_config enc2.4 " .. authmode)
    end
    return jsonc.stringify({ success = true, error = nil })
end

function WhitelistedDevices()
    print("\r\n")
    local cursor = io.open("/data/wicrypt/database/whitelisted_devices.json", "r")
    if cursor == nil then
        return jsonc.stringify({ data = {}, success = false, error = "Failed to open whitelisted_devices.json" })
    end
    local content = cursor:read("*all")
    cursor:close()
    return jsonc.stringify({ data = jsonc.parse(content).data.records, success = true, error = nil })
end

function WhitelistDev(mac, name)
    print("\r\n")
    local resp = util.exec("sh /etc/wicrypt/shellscripts/splash_page.sh whitelistDevice " .. mac .. " " .. name)
    return jsonc.stringify(jsonc.parse(resp))
end

function DelistDev(mac, name)
    print("\r\n")
    local resp = util.exec("sh /etc/wicrypt/shellscripts/splash_page.sh unwhitelist " .. mac .. " " .. name)
    return jsonc.stringify(jsonc.parse(resp))
end

function DownloadWhitelisted()
    print("\r\n")
    util.exec("sh /etc/wicrypt/shellscripts/splash_page.sh whitelistedDevices")
    return jsonc.stringify({ success = true, error = nil })
end

function DownloadFirmwFile()
    print("\r\n")
    local suc, exitCode, code = os.execute("sh /etc/wicrypt/shellscripts/splash_page.sh staticFiles")
    if suc then
        return jsonc.stringify({ message = "required files downloaded successfully", error = nil, success = true })
    else
        return jsonc.stringify({ error = "Failed to download required files", message = nil, success = false })
    end
end

function DataUsage()
    print("\r\n")
    local res = util.exec(
        "sed -i 's/\"\"/\"/g' /data/wicrypt/database/data_usage.json && cat /data/wicrypt/database/data_usage.json")
    return jsonc.stringify({ data = jsonc.parse(res), success = true, error = nil })
end

function LinkHub(code)
    print("\r\n")
    local ifInfo = IfDevicesInfo()
    local mac = util.ubus("luci-rpc", "getNetworkDevices", {}).br0.mac
    local brd_info = util.ubus("system", "board")
    local license = uci:get("wicrypt", "licence", "key")
    local imei = util.exec("cat /tmp/.devinfo_module_data | grep \"module_imei\" | cut -d':' -f2")

    local body = jsonc.stringify({
        linkCode = code,
        imei = imei,
        bssid = ifInfo[1].bssid,
        ssid = ifInfo[1].ssid,
        architecture = brd_info.system,
        deviceModel = brd_info.model,
        macAddress = mac,
        releaseVersion = "1.0.0",
    })

    local curlCommand = string.format(
        'curl -s -X POST -H "Content-Type: application/json" -H "x-license-key: %s" -d \'%s\' %s/api/v1/device/link-hub',
        license,
        body,
        SERVER
    )
    local result = util.exec(curlCommand)
    local res = jsonc.parse(result)

    if res.isSuccessful == true then
        local devHash = res.data.devicePinHash
        local devPhrase = res.data.deviceSecurityPhrase

        -- Set the values
        uci:set("wicrypt", "login", "hash", devHash)
        uci:set("wicrypt", "login", "phrase", devPhrase)

        -- Commit the changes
        uci:commit("wicrypt")

        -- Get the values after setting them
        local hash = uci:get("wicrypt", "login", "hash")
        local phrase = uci:get("wicrypt", "login", "phrase")
    end

    return result
end

function FirmwVersion()
    print("\r\n")
    local asset_ver = util.exec("uci get wicrypt.firmwareAssetRelease.releaseVersion")
    local ui_ver = util.exec("uci get wicrypt.firmware.dist_version")
    return jsonc.stringify({ data = { firmware_version = asset_ver, ui_version = ui_ver }, success = true, error = nil })
end

local function fetch_post_data()
    local content_length = tonumber(os.getenv("CONTENT_LENGTH"))
    if content_length then
        local post_data = ""
        local chunk
        repeat
            chunk = io.read(1024) -- Read 1 KB at a time
            if chunk then
                post_data = post_data .. chunk
            end
        until not chunk
        return post_data
    else
        return nil
    end
end

local function validate_session()
    print("\r\n")
    return cjson.encode({ success = true, error = nil })
end

local function api()
    local http_method = os.getenv("REQUEST_METHOD")
    if http_method == "POST" then
        local post_data = fetch_post_data()
        local json_data = cjson.decode(post_data)
        local cookies = os.getenv("HTTP_COOKIE") or ""
        local session_id = cookies:match("sessionId=([^;]+)")
        if session_id == "00000000000000000000000000000000" then
            print("\r\n")
            return cjson.encode({ error = "Invalid Session", success = false })
        end
        local cmd = json_data.cmd or ""

        if cmd == "login" then
            return Login(json_data.password)
        else
            local session = SessionRetrieve(session_id)
            if session.error ~= nil then
                return session
            end
        end
        if cmd == "board_info" then
            return BoardInfo()
        elseif cmd == "firmw_enable" then
            return FirmwEnable()
        elseif cmd == "firmw_disable" then
            return FirmwDisable()
        elseif cmd == "reg_status" then
            return RegStatus()
        elseif cmd == "firmw_status" then
            return FirmwServiceStatus()
        elseif cmd == "memory_info" then
            return MemoryInfo()
        elseif cmd == "wireless" then
            return Wireless()
        elseif cmd == "transfer_speed" then
            return transferSpeed()
        elseif cmd == "signal_strenght" then
            return signalStrenght()
        elseif cmd == "dhcplease" then
            return DhcpLease()
        elseif cmd == "register_device" then
            return RegisterDevice(json_data.email, json_data.pin)
        elseif cmd == "wifis" then
            return WifiDevices()
        elseif cmd == "change_ssid" then
            return ChangeSsid(json_data.devname, json_data.newssid)
        elseif cmd == "change_wireless_key" then
            return ChangeWirelessAuthConfig(json_data.devname, json_data.authmode, json_data.newkey)
        elseif cmd == "setup_firmw" then
            return DownloadFirmwFile()
        elseif cmd == "whitelisted" then
            return WhitelistedDevices()
        elseif cmd == "whitelist" then
            return WhitelistDev(json_data.mac, json_data.name)
        elseif cmd == "delist" then
            return DelistDev(json_data.mac, json_data.name)
        elseif cmd == "download_whitelisted" then
            return DownloadWhitelisted()
        elseif cmd == "data_usg" then
            return DataUsage()
        elseif cmd == "firmw_version" then
            return FirmwVersion()
        elseif cmd == "link_hub" then
            return LinkHub(json_data.code)
        elseif cmd == "validate_session" then
            return validate_session()
        else
            return cjson.encode({ error = "Method not found", success = false })
        end
    else
        return cjson.encode({ error = "Method not allowed", success = false })
    end
end

local http_method = os.getenv("REQUEST_METHOD")
if http_method == "OPTIONS" then
    print("Access-Control-Allow-Origin: *")
    print("Access-Control-Allow-Methods: POST, GET, OPTIONS")
    print("Access-Control-Allow-Headers: Content-Type")
    print("Access-Control-Max-Age: 86400")
    print("Content-Type: application/json")
    print("\r\n")
    return
end
print("Access-Control-Allow-Origin: *")
print("Access-Control-Allow-Methods: POST, OPTIONS")
print("Access-Control-Allow-Headers: Content-Type")
print("Access-Control-Max-Age: 86400")
print("Content-Type: application/json")
print(api())