#!/usr/bin/env luajit
local function escape(s)
return s:gsub("<", "<"):gsub("<", "<")
end
local function urldecode(s)
if s == nil then return nil end
return s:gsub("+", " "):gsub("%%20", " ")
end
local function urlencode(s)
if s == nil then return nil end
return s:gsub(" ", "%%20")
end
local function parse_query(q)
if q == nil then return {} end
local data = {}
for pair in string.gmatch(q, "([^&]+)") do
local flag = string.match(pair, "^([^=]+)$")
if flag ~= nil then
data[flag] = "1"
else
local key, value = string.match(pair, "^([^=]+)=([^=]*)$")
if key ~= nil and value ~= nil then
data[key] = urldecode(value)
end
end
end
return data
end
local path = os.getenv("PATH_INFO")
local method = os.getenv("REQUEST_METHOD")
local query = parse_query(os.getenv("QUERY_STRING"))
local stylesheet = [[
/* body { background-color: #161616; }
h1, h2, h3, h4, h5, h6, p, label, a { color: #e2e2e2; } */
.amount-presets form { display: inline-block; width: 60px }
.amount-pos { color: green; }
.amount-neg { color: red; }
nav h2 { display: inline-block }
.notif { padding: 0.5em; margin: 0.5em; background-color: #ddd; }
.notif p { margin: 5px }
]]
local script = [[
]]
local function respond(status, title, body)
print(string.format("Status: %d", status))
print("Content-Type: text/html")
print("")
print(string.format([[
%s
]], escape(title), stylesheet, script))
body()
print("")
end
local function respond_error(message)
respond(400, "Error", function()
print(string.format("
Error: %s
", escape(message)))
end)
end
local function redirect(path)
print("Status: 307")
print(string.format("Location: %s", path))
print()
end
local function form_data()
return parse_query(io.read())
end
local function read_log()
local log = io.open("log", "r")
if log == nil then
return function() return nil end
end
local lines = log:lines("l")
return function()
local l = lines()
if l == "" or l == nil then
return nil
end
local time, username, amount, comment = string.match(l, "(%d+),([%w_ -]+),(-?%d+),([%w_ -]*)")
return tonumber(time), username, tonumber(amount), comment
end
end
local function read_products()
local log = io.open("products", "r")
if log == nil then
return function() return nil end
end
local lines = log:lines("l")
return function()
local l = lines()
if l == "" or l == nil then
return nil
end
local barcode, amount, name = string.match(l, "([%w_-]+),(-?%d+),([%w_ -]*)")
return barcode, tonumber(amount), name
end
end
local function balances()
local users = {}
for _, username, amount, _ in read_log() do
users[username] = (users[username] or 0) + amount
end
return users
end
local function r_user()
if path == nil then
return respond_error("no path")
end
local username = urldecode(path:sub(2))
if username == nil or username:match("^([%w_ -]+)$") == nil then
return respond_error("username invalid")
end
local notif = nil
if method == "POST" then
local data = form_data()
local amount = nil
local comment = ""
if data.barcode then
for p_barcode, p_amount, p_name in read_products() do
if p_barcode == data.barcode then
amount = p_amount
comment = p_name
end
end
else
amount = tonumber(data.amount)
comment = data.comment or ""
end
if amount == nil then
return respond_error("amount invalid")
end
if comment:match("^[%w_ -]*$") == nil then
return respond_error("comment invalid")
end
local log = io.open("log", "a+")
if log == nil then
return respond_error("failed to open log")
end
local time = os.time()
log:write(string.format("%d,%s,%s,%s\n", time, username, amount, comment))
log:flush()
log:close()
notif = string.format(
"
Transaction successful: %.02f€ (%s)
",
amount >= 0 and "pos" or "neg", amount / 100, escape(comment)
)
end
return respond(200, username, function()
print(string.format("
%s
", username))
local balance = balances()[username]
local new_user = balance == nil
balance = balance or 0
if new_user then
print([[
This user account does not exist yet. It will only be created after the first transaction.
]])
end
if notif then
print(notif)
end
print(string.format("
Current balance: %.02f€
", balance >= 0 and "pos" or "neg",
balance / 100))
print([[
]])
print("
")
for _, type in ipairs({ 1, -1 }) do
for _, amount in ipairs({ 50, 100, 150, 200, 500, 1000 }) do
print(string.format([[
]], amount * type, ({ [-1] = "-", [1] = "+" })[type], amount / 100,
({ [-1] = "neg", [1] = "pos" })[type]))
end
print(" ")
end
print("
")
end)
end
local function r_log()
return respond(200, "Log", function()
print("
")
print("
Time
Username
Amount
Comment
")
for time, username, amount, comment in read_log() do
print(string.format("
%d
%s
%.02f€
%s
", time, escape(username),
amount / 100, escape(comment)))
end
print("
")
end)
end
local function r_index()
return respond(200, "Users", function()
print([[
]])
print("
")
for username, balance in pairs(balances()) do
print(string.format("
", escape(username), escape(username),
balance / 100))
end
print("
")
end)
end
local function r_create_user()
local username = query.create_user
if username:match("^([%w_ -]+)$") == nil then
return respond_error("invalid username " .. username)
end
return redirect(string.format("/%s", urlencode(username)))
end
if path == "/" then
if query.log then
return r_log()
elseif query.create_user then
return r_create_user()
else
return r_index()
end
else
return r_user()
end