process_pending_btc_transactions

  1#!/usr/bin/ruby
  2# frozen_string_literal: true
  3
  4# Usage: bin/process_pending-btc_transactions '{
  5#        oxr_app_id = "",
  6#        required_confirmations = 3,
  7#        notify_using = {
  8#          jid = "",
  9#          password = "",
 10#          target = \(jid: Text) -> "+12266669977@cheogram.com",
 11#          body = \(jid: Text) -> \(body: Text) -> "/msg ${jid} ${body}",
 12#        },
 13#        electrum = env:ELECTRUM_CONFIG,
 14#        plans = ./plans.dhall,
 15#        activation_amount = 10000
 16#        }'
 17
 18require "bigdecimal"
 19require "dhall"
 20require "money/bank/open_exchange_rates_bank"
 21require "net/http"
 22require "nokogiri"
 23require "pg"
 24require "redis"
 25
 26require_relative "../lib/blather_notify"
 27require_relative "../lib/electrum"
 28
 29CONFIG =
 30	Dhall::Coder
 31	.new(safe: Dhall::Coder::JSON_LIKE + [Symbol, Proc])
 32	.load(ARGV[0], transform_keys: :to_sym)
 33
 34REDIS = Redis.new
 35ELECTRUM = Electrum.new(**CONFIG[:electrum])
 36
 37DB = PG.connect(dbname: "jmp")
 38DB.type_map_for_results = PG::BasicTypeMapForResults.new(DB)
 39DB.type_map_for_queries = PG::BasicTypeMapForQueries.new(DB)
 40
 41BlatherNotify.start(
 42	CONFIG[:notify_using][:jid],
 43	CONFIG[:notify_using][:password]
 44)
 45
 46unless (cad_to_usd = REDIS.get("cad_to_usd")&.to_f)
 47	oxr = Money::Bank::OpenExchangeRatesBank.new(Money::RatesStore::Memory.new)
 48	oxr.app_id = CONFIG.fetch(:oxr_app_id)
 49	oxr.update_rates
 50	cad_to_usd = oxr.get_rate("CAD", "USD")
 51	REDIS.set("cad_to_usd", cad_to_usd, ex: 60 * 60)
 52end
 53
 54canadianbitcoins = Nokogiri::HTML.parse(
 55	Net::HTTP.get(URI("https://www.canadianbitcoins.com"))
 56)
 57
 58bitcoin_row = canadianbitcoins.at("#ticker > table > tbody > tr")
 59raise "Bitcoin row has moved" unless bitcoin_row.at("td").text == "Bitcoin"
 60
 61btc_sell_price = {}
 62btc_sell_price[:CAD] = BigDecimal(
 63	bitcoin_row.at("td:nth-of-type(3)").text.match(/^\$(\d+\.\d+)/)[1]
 64)
 65btc_sell_price[:USD] = btc_sell_price[:CAD] * cad_to_usd
 66
 67class Plan
 68	def self.for_customer(customer)
 69		row = DB.exec_params(<<-SQL, [customer.id]).first
 70			SELECT customer_plans.plan_name, UPPER(date_range) - LOWER(date_range) < '2 seconds' AS pd
 71			FROM customer_plans LEFT JOIN plan_log
 72				ON customer_plans.customer_id = plan_log.customer_id
 73				AND plan_log.date_range -|- tsrange(expires_at, expires_at, '[]')
 74			WHERE customer_plans.customer_id=$1 LIMIT 1
 75		SQL
 76		return nil unless row
 77
 78		from_name(customer, row["plan_name"], klass: row["pd"] ? Pending : Plan)
 79	end
 80
 81	def self.from_name(customer, plan_name, klass: Plan)
 82		return unless plan_name
 83
 84		plan = CONFIG[:plans].find { |p| p[:name] == plan_name }
 85		klass.new(customer, plan) if plan
 86	end
 87
 88	def initialize(customer, plan)
 89		@customer = customer
 90		@plan = plan
 91	end
 92
 93	def name
 94		@plan[:name]
 95	end
 96
 97	def currency
 98		@plan[:currency]
 99	end
100
101	def bonus_for(fiat_amount)
102		return BigDecimal(0) if fiat_amount <= 15
103
104		fiat_amount * case fiat_amount
105		when (15..29.99)
106			0.01
107		when (30..139.99)
108			0.03
109		else
110			0.05
111		end
112	end
113
114	def price
115		BigDecimal(@plan[:monthly_price].to_i) * 0.0001
116	end
117
118	def notify_any_pending_plan!; end
119
120	class Pending < Plan
121		def initialize(customer, plan)
122			super
123			@go_until = Date.today >> 1
124		end
125
126		def activation_amount
127			camnt = BigDecimal(CONFIG[:activation_amount].to_i) * 0.0001
128			[camnt, price].max
129		end
130
131		def notify_any_pending_plan!
132			if @customer.balance < activation_amount
133				@customer.notify(
134					"Your account could not be activated because your " \
135					"balance of $#{@customer.balance} is less that the " \
136					"required activation amount of $#{activation_amount}. " \
137					"Please buy more credit to have your account activated."
138				)
139			else
140				notify_approved
141			end
142		end
143
144	protected
145
146		def notify_approved
147			@customer.notify(
148				"Your JMP account has been approved. To complete " \
149				"your signup, click/tap here: xmpp:cheogram.com " \
150				"and send register jmp.chat to the bot."
151			)
152		end
153	end
154end
155
156class Customer
157	def initialize(customer_id)
158		@customer_id = customer_id
159	end
160
161	def id
162		@customer_id
163	end
164
165	def notify(body)
166		jid = REDIS.get("jmp_customer_jid-#{@customer_id}")
167		raise "No JID for #{customer_id}" unless jid
168
169		BlatherNotify.say(
170			CONFIG[:notify_using][:target].call(jid),
171			CONFIG[:notify_using][:body].call(jid, body)
172		)
173	end
174
175	def plan
176		Plan.for_customer(self)
177	end
178
179	def balance
180		result = DB.exec_params(<<-SQL, [@customer_id]).first&.[]("balance")
181			SELECT balance FROM balances WHERE customer_id=$1
182		SQL
183		result || BigDecimal(0)
184	end
185
186	def add_btc_credit(txid, btc_amount, fiat_amount)
187		return unless add_transaction(txid, fiat_amount, "Bitcoin payment")
188
189		if (bonus = plan.bonus_for(fiat_amount)).positive?
190			add_transaction("bonus_for_#{txid}", bonus, "Bitcoin payment bonus")
191		end
192		notify_btc_credit(txid, btc_amount, fiat_amount, bonus)
193	end
194
195	def notify_btc_credit(txid, btc_amount, fiat_amount, bonus)
196		tx_hash, = txid.split("/", 2)
197		notify([
198			"Your Bitcoin transaction of #{btc_amount.to_s('F')} BTC ",
199			"has been added as $#{'%.4f' % fiat_amount} (#{plan.currency}) ",
200			("+ $#{'%.4f' % bonus} bonus " if bonus.positive?),
201			"to your account.\n(txhash: #{tx_hash})"
202		].compact.join)
203	end
204
205	def add_transaction(id, amount, note)
206		args = [@customer_id, id, amount, note]
207		DB.exec_params(<<-SQL, args).cmd_tuples.positive?
208			INSERT INTO transactions
209				(customer_id, transaction_id, settled_after, amount, note)
210			VALUES
211				($1, $2, LOCALTIMESTAMP, $3, $4)
212			ON CONFLICT (transaction_id) DO NOTHING
213		SQL
214	end
215end
216
217done = REDIS.hgetall("pending_btc_transactions").map { |(txid, customer_id)|
218	tx_hash, address = txid.split("/", 2)
219	transaction = ELECTRUM.gettransaction(tx_hash)
220	next unless transaction.confirmations >= CONFIG[:required_confirmations]
221
222	btc = transaction.amount_for(address)
223	if btc <= 0
224		# This is a send, not a receive, do not record it
225		REDIS.hdel("pending_btc_transactions", txid)
226		next
227	end
228	DB.transaction do
229		customer = Customer.new(customer_id)
230		if (plan = customer.plan)
231			amount = btc * btc_sell_price.fetch(plan.currency).round(4, :floor)
232			customer.add_btc_credit(txid, btc, amount)
233			plan.notify_any_pending_plan!
234			REDIS.hdel("pending_btc_transactions", txid)
235			txid
236		else
237			warn "No plan for #{customer_id} cannot save #{txid}"
238		end
239	end
240}
241
242puts done.compact.join("\n")