src/wise.sgl — sigil-wise

1;;; (wise) - Wise (TransferWise) API client library.

2;;;

3;;; Provides functions for querying profiles, balances, and transaction

4;;; statements from the Wise API using a personal API token.

6(define-library (wise)

7 (import (sigil core)

8 (sigil dict)

9 (sigil string)

10 (sigil struct)

11 (sigil json)

12 (only (sigil array) array-map)

13 (only (sigil http) url-encode-value build-query-string)

14 (sigil http client)

15 (only (sigil time) parse-iso-date format-iso-date

16 days-in-month add-days date-compare))

18 (export ;; Client

19 wise-client

20 wise-client?

21 wise-client-token

22 wise-client-base-url

24 ;; Records

25 wise-profile

26 wise-profile?

27 wise-profile-id

28 wise-profile-type

29 wise-profile-name

31 wise-balance

32 wise-balance?

33 wise-balance-id

34 wise-balance-currency

35 wise-balance-type

36 wise-balance-amount

37 wise-balance-reserved-amount

39 wise-transaction

40 wise-transaction?

41 wise-transaction-type

42 wise-transaction-date

43 wise-transaction-amount

44 wise-transaction-currency

45 wise-transaction-details

46 wise-transaction-reference-number

47 wise-transaction-running-balance

49 ;; API functions

50 wise-profiles

51 wise-balances

52 wise-statement

53 wise-transactions

55 ;; Parsing

56 parse-profile

57 parse-balance

58 parse-transaction

60 ;; Utilities

61 wise-date-windows)

63 (begin

65 ;; ---------------------------------------------------------------

66 ;; Records

67 ;; ---------------------------------------------------------------

69 (define-struct wise-client

70 (token)

71 (base-url default: "https://api.wise.com"))

73 (define-struct wise-profile

74 (id)

75 (type)

76 (name))

78 (define-struct wise-balance

79 (id)

80 (currency)

81 (type)

82 (amount)

83 (reserved-amount))

85 (define-struct wise-transaction

86 (type)

87 (date)

88 (amount)

89 (currency)

90 (details)

91 (reference-number)

92 (running-balance))

94 ;; ---------------------------------------------------------------

95 ;; Internal helpers

96 ;; ---------------------------------------------------------------

98 ;;; Build authorization headers for the Wise API.

99 (define (wise-auth-headers client)

100 #{ authorization: (string-append "Bearer " (wise-client-token client)) })

101

102 ;;; Build an API URL from the client base URL and path segments.

103 (define (wise-api-url client . parts)

104 (apply build-api-url (wise-client-base-url client) parts))

105

106

107 ;;; Response checker with Wise-specific error context.

108 (define check-wise-response

109 (make-response-checker

110 name: "Wise API"

111 handlers: (list

112

          (cons 403 "This may be an SCA restriction for UK/EEA accounts. See https://docs.wise.com for SCA re-authentication.")

113 (cons 429 "Rate limited. Retry after a delay."))))

114

115 ;;; Perform an authenticated GET request and return parsed JSON.

116 (define (wise-get/json client url)

117 (check-wise-response

118 (http-get url headers: (wise-auth-headers client))))

119

120 ;; ---------------------------------------------------------------

121 ;; Response parsing

122 ;; ---------------------------------------------------------------

123

124 ;;; Parse a profile dict from the API response into a wise-profile record.

125 (define (parse-profile data)

126 (let ((full-name (dict-ref data fullName: #f))

127 (details (dict-ref data details: #f)))

128 (wise-profile

129 id: (dict-ref data id:)

130 type: (dict-ref data type:)

131 name: (or full-name

132 (if details

133 (string-append

134 (dict-ref details firstName: "")

135 " "

136 (dict-ref details lastName: ""))

137 "")))))

138

139 ;;; Parse a balance dict from the API response into a wise-balance record.

140 (define (parse-balance data)

141 (let ((amount-obj (dict-ref data amount: #{}))

142 (reserved-obj (dict-ref data reservedAmount: #{})))

143 (wise-balance

144 id: (dict-ref data id:)

145 currency: (dict-ref data currency:

146 (dict-ref amount-obj currency: ""))

147 type: (dict-ref data type: "STANDARD")

148 amount: (dict-ref amount-obj value: 0)

149 reserved-amount: (dict-ref reserved-obj value: 0))))

150

151 ;;; Parse a transaction dict from the API response into a wise-transaction record.

152 (define (parse-transaction data)

153 (let ((amount-obj (dict-ref data amount: #{}))

154 (balance-obj (dict-ref data runningBalance: #{})))

155 (wise-transaction

156 type: (dict-ref data type:)

157 date: (dict-ref data date:)

158 amount: (dict-ref amount-obj value: 0)

159 currency: (dict-ref amount-obj currency: "")

160 details: (dict-ref data details: #{})

161 reference-number: (dict-ref data referenceNumber: "")

162 running-balance: (dict-ref balance-obj value: 0))))

163

164 ;; ---------------------------------------------------------------

165 ;; Date windowing

166 ;; ---------------------------------------------------------------

167

168 ;;; Maximum number of days per statement request (Wise limit).

169 (define wise-max-window-days 469)

170

171 ;;; Split a date range into windows of at most wise-max-window-days.

172 ;;; Returns a list of (start-iso . end-iso) pairs.

173 (define (wise-date-windows start-iso end-iso)

174 (let ((start (parse-iso-date start-iso))

175 (end (parse-iso-date end-iso)))

176 (let loop ((current start) (windows '()))

177 (if (>= (date-compare current end) 0)

178 (reverse windows)

179 (let* ((window-end (add-days current wise-max-window-days))

180 (actual-end (if (> (date-compare window-end end) 0)

181 end

182 window-end)))

183 (loop actual-end

184 (cons (cons (format-iso-date current)

185 (format-iso-date actual-end))

186 windows)))))))

187

188 ;; ---------------------------------------------------------------

189 ;; API functions

190 ;; ---------------------------------------------------------------

191

192 ;;; Fetch all profiles for the authenticated user.

193 ;;; Returns a list of wise-profile records.

194 (define (wise-profiles client)

195 (let ((data (wise-get/json client

196 (wise-api-url client "v2" "profiles"))))

197 (if (array? data)

198 (array->list (array-map parse-profile data))

199 '())))

200

201 ;;; Fetch balances for a profile.

202 ;;; Returns a list of wise-balance records.

203 (define (wise-balances client profile-id)

204 (let ((url (string-append

205 (wise-api-url client "v4" "profiles"

206 (number->string profile-id)

207 "balances")

208 "?types=STANDARD")))

209 (let ((data (wise-get/json client url)))

210 (if (array? data)

211 (array->list (array-map parse-balance data))

212 '()))))

213

214 ;;; Fetch a balance statement for a single balance and date range.

215 ;;; Automatically splits the range into windows of <= 469 days.

216 ;;; Returns a list of wise-transaction records.

217 (define (wise-statement client profile-id balance-id currency

218 interval-start interval-end)

219 (let ((windows (wise-date-windows interval-start interval-end))

220 (pid (number->string profile-id))

221 (bid (number->string balance-id)))

222 (let loop ((wins windows) (txns '()))

223 (if (null? wins)

224 (reverse txns)

225 (let* ((win (car wins))

226 (url (string-append

227 (wise-api-url client "v1" "profiles" pid

228 "balance-statements" bid

229 "statement.json")

230 (build-query-string

231 (list (cons "currency" currency)

232 (cons "intervalStart" (car win))

233 (cons "intervalEnd" (cdr win))

234 (cons "type" "COMPACT")))))

235 (data (wise-get/json client url))

236 (raw-txns (dict-ref data transactions: #[])))

237 (loop (cdr wins)

238 (append (reverse

239 (array->list

240 (array-map parse-transaction raw-txns)))

241 txns)))))))

242

243 ;;; Fetch transactions across all balances for a profile and date range.

244 ;;; Optionally filter by currency (pass #f for all currencies).

245 ;;; Returns a list of wise-transaction records.

246 (define (wise-transactions client profile-id interval-start interval-end

247 . rest)

248 (let ((currency-filter (if (null? rest) #f (car rest))))

249 (let ((balances (wise-balances client profile-id)))

250 (let ((filtered (if currency-filter

251 (filter (lambda (b)

252 (string=? (wise-balance-currency b)

253 currency-filter))

254 balances)

255 balances)))

256 (let loop ((bals filtered) (all-txns '()))

257 (if (null? bals)

258 (reverse all-txns)

259 (let* ((bal (car bals))

260 (txns (wise-statement client profile-id

261 (wise-balance-id bal)

262 (wise-balance-currency bal)

263 interval-start interval-end)))

264 (loop (cdr bals)

265 (append (reverse txns) all-txns)))))))))

266

267 ))