opus-apps/swshop/swshop.lua

local Util = require('util')

local fs        = _G.fs
local os        = _G.os
local shell     = _ENV.shell

local programDir = fs.getDir(shell.getRunningProgram())
os.loadAPI(programDir .. '/'.. 'json')

local w   = require("w")
local r   = require("r")
local k   = require("k")
local jua = require("jua")

local await     = jua.await
local device    = _G.device
local json      = _G.json
local rs        = _G.rs
local textutils = _G.textutils

local chat = device['plethora:chat']

rs.setOutput('top', false)

r.init(jua)
w.init(jua)
k.init(jua, json, w, r)

local function Syntax()
  error('Syntax: swshop [domain] [password | privateKey] [isPrivateKey]')
end

local args = { ... }
local domain = args[1] or Syntax()
local password = args[2] or Syntax()
local privatekey = args[3] and args[2] or k.toKristWalletFormat(password)
local address = k.makev2address(privatekey)
local transactions = Util.readTable('/usr/swshop.log') or { }

jua.on("terminate", function()
  rs.setOutput('top', false)
  jua.stop()
  _G.printError("Terminated")
end)

local function getItemDetails(item)
  local f = fs.open('usr/config/shop', "r")
  if f then
    local t = f.readAll()
    f.close()
    t = textutils.unserialize(t)
    for key, v in pairs(t) do
      if v.name == item then
        return key, v.price
      end
    end
  end
end

local function logTransaction(transaction, details)
  transaction = Util.shallowCopy(transaction)
  Util.merge(transaction, details)
  table.insert(transactions, transaction)
  Util.writeTable('/usr/swshop.log', transactions)
end

local function handleTransaction(transaction)
  local from = transaction.from
  local to = transaction.to
  local value = transaction.value
  if to ~= address or not transaction.metadata then return end

  local metadata = k.parseMeta(transaction.metadata)
  if not metadata.domain or metadata.domain ~= domain then return end

  local recipient = metadata.meta and (metadata.meta["return"] or from) or from
  print("Handling transaction from ", recipient)
  print('purchase: ' .. tostring(metadata.name))
  print('value: ' .. value)

  local t = {
    to = transaction.to,
    from = transaction.from,
    value = transaction.value,
    id = metadata.name,
  }

  local function refundTransaction(amount, reason)
    print("Refunding to ", recipient)
    await(k.makeTransaction, privatekey, recipient, amount, reason)
    logTransaction(t, { refund = amount, reason = reason })
  end

  t.itemId, t.price = getItemDetails(metadata.name)
  if not t.itemId or not t.price then
    print('invalid item')
    logTransaction(t, { reason = 'invalid item' })
    --return refundTransaction(value, "error=Item specified is not valid")
    return -- there could be multiple stores...
  end

  if value < t.price then
    print('value too low')
    return refundTransaction(value, "error=Please pay the price listed on-screen.")
  end

  local count = math.floor(value / t.price)
  local uid = math.random()
  print(string.format('requesting %d of %s', count, t.itemId))
  os.queueEvent('shop_provide', t.itemId, count, uid)
  local timerId = os.startTimer(60)
  while true do
    local e, p1, p2 = os.pullEvent()
    if e == 'timer' and p1 == timerId then
      print('timed out waiting for provide')
      refundTransaction(value, "error=Timed out attempting to provide items")
      break

    elseif e == 'shop_provided' and p1 == uid then
      local extra = value - (t.price * p2)
      logTransaction(t, { purchased = p2 })
      if chat and chat.tell then
        local msg = string.format('PURCHASE: %s bought %d %s for %s',
          recipient, p2, t.itemId, t.price * p2)
        chat.tell(msg)
      end
      if extra > 0 then
        print('extra: ' .. extra)
        refundTransaction(extra, "message=Here's your change!")
      end
      break
    end
  end
end

local function connect()
  print('opening store for: ' .. domain)

  local success, ws = await(k.connect, privatekey)
  assert(success, "Failed to get websocket URL")

  print("Connected to websocket.")
  rs.setOutput('top', true)

  success = await(ws.subscribe, "ownTransactions", function(data)
    local transaction = data.transaction
    handleTransaction(transaction)
  end)
  assert(success, "Failed to subscribe to event")
end

local s, m = pcall(function()
  jua.go(function()
    print("Ready")
    connect()
  end)
end)

rs.setOutput('top', false)
if not s then
  error(m, 2)
end