#!/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 function load_config()
local log = io.open("config", "r")
if log == nil then return {} end
local config = {}
for l in log:lines("l") do
if l ~= "" and l[0] ~= "#" then
local key, value = string.match(l, "^([^=]+)=([^=]*)")
if key ~= nil and value ~= nil then
config[key] = value
end
end
end
return config
end
local config = load_config()
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.error { background-color: #faa; }
.notif p { margin: 5px; }
form.box { border: 2px solid grey; padding: 0.5em; margin: 0.5em; display: inline-block; }
form h3 { margin: 5px; }
]]
local script = [[
document.addEventListener("keypress", ev => {
if (!(document.activeElement instanceof HTMLInputElement)) {
if (ev.code.startsWith("Digit"))
document.forms.buy_product.product.value += ev.code.substring(5)
if (ev.code == "Enter")
document.forms.buy_product.submit()
}
})
]]
local function respond(status, title, body)
print(string.format("Status: %d", status))
print("Content-Type: text/html")
print("")
print(string.format([[
%s
%s
]], escape(title), stylesheet, script, config.head_extra or ""))
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 format_duration(t)
if t > 86400 then return string.format("%d days", t / 86400) end
if t > 3600 then return string.format("%d hours", t / 3600) end
if t > 60 then return string.format("%d minutes", t / 60) end
return string.format("%d seconds", t)
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 last_txns()
local users = {}
for time, username, _, _ in read_log() do
users[username] = time
end
return users
end
local function error_box(message)
return string.format([[
Error: %s
]], message)
end
local function r_user_post(username)
local data = form_data()
local amount = nil
local comment = ""
if data.product then
for p_barcode, p_amount, p_name in read_products() do
if p_barcode == data.product then
amount = p_amount
comment = p_name
end
end
if amount == nil then
return error_box("unknown product")
end
else
amount = tonumber(data.amount)
comment = data.comment or ""
end
if amount == nil then
return error_box("amount invalid")
end
if comment:match("^[%w_ -]*$") == nil then
return error_box("comment invalid")
end
local log = io.open("log", "a+")
if log == nil then
return error_box("failed to open log")
end
local time = os.time()
log:write(string.format("%d,%s,%d,%s\n", time, username, amount, comment))
log:flush()
log:close()
return string.format([[
Transaction successful: %.02f€ (%s)
]],
amount >= 0 and "pos" or "neg", amount / 100,
escape(comment),
config.transaction_sound or ""
)
end
local function r_user(username)
local notif = nil
if method == "POST" then
notif = r_user_post(username)
end
return respond(200, username, function()
print(string.format("
%s
", username))
local balance = balances()[username]
local last_txn = last_txns()[username]
local new_user = balance == nil
balance = balance or 0
if notif then print(notif) end
if new_user then
print([[
This user account does not exist yet. It will only be created after the first transaction.
]])
else
print(string.format([[
Current balance: %.02f€
]], balance >= 0 and "pos" or "neg", balance / 100))
print(string.format([[
Last transaction added %s ago. View user log
]], format_duration(os.time() - last_txn), username))
end
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(filter)
return respond(200, "Log", function()
print("
")
print("
Time
Username
Amount
Comment
")
for time, username, amount, comment in read_log() do
if filter == nil or filter == username then
print(string.format(
"
%d (%s ago)
%s
%.02f€
%s
",
time, format_duration(os.time() - time),
escape(username),
amount >= 0 and "pos" or "neg", amount / 100,
escape(comment)
))
end
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
local function extract_username()
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 nil
end
return 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
local username = extract_username()
if username == nil then
return respond_error("username invalid")
elseif query.log then
return r_log(username)
else
return r_user(username)
end
end