add dhiraagu bill pay

app/src/main/java/sh/sar/basedbank/api/dhiraagu/DhiraaguPaymentClient.kt

@@ -13,14 +13,14 @@ import java.util.Locale
 import java.util.concurrent.TimeUnit
 
 /**
- * Dhiraagu prepaid reload through the dhiraagu.com.mv "Easy TopUp" page, paid by card on BML's
- * merchant gateway. Dhiraagu only builds the order; the money moves on the BML Merchant Services
- * transaction [createBmlTransaction] hands back, which is paid like any card-only BML merchant
- * link. See `docs/dhiraaguapi/02-reload.md`.
+ * Dhiraagu prepaid reload ("Easy TopUp") and bill payment ("Easy Pay") through dhiraagu.com.mv,
+ * paid by card on BML's merchant gateway. Dhiraagu only builds the order; the money moves on the
+ * BML Merchant Services transaction handed back, which is paid like any card-only BML merchant
+ * link. See `docs/dhiraaguapi/02-reload.md` and `docs/dhiraaguapi/03-bill-pay.md`.
  *
  * Every call blocks, so run it on an IO thread.
  */
-class DhiraaguReloadClient {
+class DhiraaguPaymentClient {
 
     private val client = OkHttpClient.Builder()
         .connectTimeout(30, TimeUnit.SECONDS)
@@ -33,11 +33,11 @@ class DhiraaguReloadClient {
      * amount paid, GST included. Returns the 24-hex BML transaction id. Throws with Dhiraagu's
      * wording when a step is refused.
      */
-    fun createBmlTransaction(number: String, amount: Int): String {
+    fun createReloadTransaction(number: String, amount: Int): String {
         val topupNonce = pageNonce("$BASE/services/easy-topup")
         val gst = gstOf(amount)
         val cart = api("cart", "recharge", topupNonce, JSONObject()
-            .put("formId", FORM_ID)
+            .put("formId", FORM_RELOAD)
             .put("serviceNumber", number)
             .put("amount", amount)
             .put("amountGST", gst.toDouble())
@@ -46,21 +46,66 @@ class DhiraaguReloadClient {
             .put("memberId", "").put("memberName", "").put("memberNId", "")
             .put("customerId", "").put("customerCode", "")
             .put("version", 2))
+        return payCart(FORM_RELOAD, cart, BigDecimal(amount))
+    }
+
+    /**
+     * Creates the bill payment order for postpaid [number] and the BML transaction paying for
+     * it: lookup (for the billing account) → cart → merchant → payment → BML transaction.
+     * [amount] is MVR, up to 2 decimal places. Returns the 24-hex BML transaction id. Throws
+     * with Dhiraagu's wording when a step is refused.
+     */
+    fun createBillPayTransaction(number: String, amount: BigDecimal): String {
+        val easyPayNonce = pageNonce("$BASE/services/easy-pay")
+        // The cart needs the billing account the number belongs to, which only the lookup gives
+        val info = call("dhiraaguIO", "infoUnlisted", easyPayNonce, JSONObject().put("number", number))
+        if (info.optJSONArray("serviceDetails")?.optJSONObject(0)?.optString("prepaidIndicator") == "Y") {
+            throw Exception("Prepaid number is not allowed.")
+        }
+        val accountNumber = info.optString("accountNumber").ifBlank { throw Exception("Invalid account/service number") }
+
+        // The page refuses some account statuses and customer types before ordering; so do we
+        val rules = runCatching { get("setting", "bill", easyPayNonce).getJSONObject("resp").getJSONObject("settingAppJson1") }.getOrNull()
+        val status = info.optString("accountStatus")
+        if (rules != null && status in rules.blockedValues("accountStatus")) {
+            throw Exception("Dhiraagu can't accept payment for this service. Contact Dhiraagu customer service. [Account Status: $status]")
+        }
+        val customerType = info.optString("customerType")
+        if (rules != null && customerType in rules.blockedValues("customerType")) {
+            throw Exception("The number is not allowed. [Customer Type: $customerType]")
+        }
+
+        val cart = api("cart", "easyPay", easyPayNonce, JSONObject()
+            .put("formId", FORM_BILL)
+            .put("serviceNumber", number)
+            .put("accountNumber", accountNumber)
+            .put("amount", money(amount))
+            .put("memberId", "").put("memberName", "").put("memberNId", "")
+            .put("billRef", "")
+            .put("billType", if (info.optString("type") == BILL_WRITE_OFF) BILL_WRITE_OFF else BILL_PAYMENT))
+        return payCart(FORM_BILL, cart, amount)
+    }
+
+    /**
+     * The payment page's half, shared by every form: picks the BML gateway, creates the payment
+     * for [cart] and has Dhiraagu create the BML transaction. Returns its 24-hex id.
+     */
+    private fun payCart(formId: Int, cart: JSONObject, amount: BigDecimal): String {
         val cartId = cart.optString("cartId").ifBlank { throw Exception("Dhiraagu didn't create the order") }
 
         // The payment page carries its own nonce, used for the rest of the order
         val paymentNonce = pageNonce("$BASE/services/payment-v2?cartid=$cartId")
-        val merchants = apiList("merchant", "form", paymentNonce, JSONObject().put("formId", FORM_ID))
+        val merchants = apiList("merchant", "form", paymentNonce, JSONObject().put("formId", formId))
         val bml = (0 until merchants.length()).map { merchants.getJSONObject(it) }
             .firstOrNull { it.optInt("gatewayId") == GATEWAY_BML }
             ?: throw Exception("Dhiraagu isn't taking BML card payments right now")
 
         val payment = api("payment", "create", paymentNonce, JSONObject()
-            .put("formId", FORM_ID)
+            .put("formId", formId)
             .put("cartId", cartId)
             .put("gatewayId", GATEWAY_BML)
             .put("dhiraaguPayNumber", "")
-            .put("amount", String.format(Locale.US, "%.2f", amount.toDouble()))
+            .put("amount", money(amount))
             .put("paymentMerchantId", bml.getString("merchantId"))
             .put("memberId", "").put("tokenize", "").put("paymentType", "")
             .put("recurringFrequency", "").put("bmlTokenId", ""))
@@ -71,13 +116,22 @@ class DhiraaguReloadClient {
             ?: throw Exception("BML didn't create the transaction")
     }
 
+    private fun money(amount: BigDecimal) =
+        String.format(Locale.US, "%.2f", amount.setScale(2, RoundingMode.HALF_UP))
+
+    /** The `val` list of a `setting` rule, e.g. `{"accountStatus":{"val":["F"]}}`. */
+    private fun JSONObject.blockedValues(rule: String): Set<String> {
+        val vals = optJSONObject(rule)?.optJSONArray("val") ?: return emptySet()
+        return (0 until vals.length()).map { vals.optString(it) }.toSet()
+    }
+
     // ── HTTP ─────────────────────────────────────────────────────────────────
 
     /** Every page embeds a `var nonce = "…"` that its API calls send as the `nonce` header. */
     private fun pageNonce(url: String): String =
-        NONCE.find(get(url))?.groupValues?.get(1) ?: throw Exception("Dhiraagu page didn't load")
+        NONCE.find(page(url))?.groupValues?.get(1) ?: throw Exception("Dhiraagu page didn't load")
 
-    private fun get(url: String): String = client.newCall(
+    private fun page(url: String): String = client.newCall(
         Request.Builder().url(url)
             .header("User-Agent", UA)
             .header("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8")
@@ -94,10 +148,16 @@ class DhiraaguReloadClient {
         call(sub, act, nonce, body).getJSONArray("resp")
 
     /** POSTs to `sdk-dhr-webapi.ashx`; throws unless `respStatus` is OK. */
-    private fun call(sub: String, act: String, nonce: String, body: JSONObject): JSONObject {
+    private fun call(sub: String, act: String, nonce: String, body: JSONObject): JSONObject =
+        send(sub, act, nonce, body.toString().toRequestBody(JSON))
+
+    /** GETs from `sdk-dhr-webapi.ashx` (the settings calls); throws unless `respStatus` is OK. */
+    private fun get(sub: String, act: String, nonce: String): JSONObject = send(sub, act, nonce, null)
+
+    private fun send(sub: String, act: String, nonce: String, body: okhttp3.RequestBody?): JSONObject {
         val text = client.newCall(
             Request.Builder().url("$API?website_id=$WEBSITE_ID&sub=$sub&act=$act")
-                .post(body.toString().toRequestBody(JSON))
+                .apply { if (body != null) post(body) }
                 .header("User-Agent", UA)
                 .header("Accept", "application/json, text/javascript, */*; q=0.01")
                 .header("X-Requested-With", "XMLHttpRequest")
@@ -112,7 +172,7 @@ class DhiraaguReloadClient {
             throw Exception("Unexpected response from Dhiraagu")
         }
         if (obj.optString("respStatus") != "OK") {
-            throw Exception(obj.optString("respMsg").ifBlank { obj.optString("resp") }.ifBlank { "Dhiraagu refused the reload" })
+            throw Exception(obj.optString("respMsg").ifBlank { obj.optString("resp") }.ifBlank { "Dhiraagu refused the payment" })
         }
         return obj
     }
@@ -126,14 +186,20 @@ class DhiraaguReloadClient {
         private val NONCE = Regex("""var nonce = "([^"]+)"""")
         private val TXN_URL = Regex("""transaction\.merchants\.bankofmaldives\.com\.mv/([0-9a-fA-F]{24})""")
 
+        /** Easy Pay's (bill payment) form id across cart / merchant / payment. */
+        private const val FORM_BILL = 1
         /** Easy TopUp's form id across cart / merchant / payment. */
-        private const val FORM_ID = 2
+        private const val FORM_RELOAD = 2
         /** Bank of Maldives in `merchant&act=form` (1 = BML, 2 = MIB, 3 = DhiraaguPay). */
         private const val GATEWAY_BML = 1
         private const val GST_RATE = 0.08
 
+        /** Easy Pay's `billType`s; the lookup's `type` says which applies. */
+        private const val BILL_PAYMENT = "BillPayment"
+        private const val BILL_WRITE_OFF = "writeOffPayments"
+
         /**
-         * The GST inside a GST-inclusive [amount], as the page works it out:
+         * The GST inside a GST-inclusive reload [amount], as the page works it out:
          * `amount × rate / (1 + rate)`, to 2 places. The number is credited `amount − gst`.
          */
         fun gstOf(amount: Int): BigDecimal {

app/src/main/java/sh/sar/basedbank/ui/home/transfer/CardPayoutTransferHandler.kt

@@ -9,7 +9,7 @@ import kotlinx.coroutines.withContext
 import sh.sar.basedbank.R
 import sh.sar.basedbank.api.bml.BmlMerchantTxnClient
 import sh.sar.basedbank.api.dhiraagu.DhiraaguClient
-import sh.sar.basedbank.api.dhiraagu.DhiraaguReloadClient
+import sh.sar.basedbank.api.dhiraagu.DhiraaguPaymentClient
 import sh.sar.basedbank.databinding.FragmentTransferBinding
 import sh.sar.basedbank.ui.home.HomeViewModel
 import sh.sar.basedbank.ui.home.TransferFragment
@@ -20,8 +20,8 @@ import java.math.RoundingMode
  * A carrier service a verified BML card can pay, through the carrier's own website and its BML
  * merchant gateway. The limits are the carrier website's, not Fahipay's.
  *
- * Only Dhiraagu reload so far. Add the others as constants once their send path lands; the
- * exhaustive `when`s over this enum point at every site that needs updating.
+ * Only Dhiraagu so far. Add the others as constants once their send path lands; the exhaustive
+ * `when`s over this enum point at every site that needs updating.
  */
 enum class CardPayoutService(
     override val label: String,
@@ -36,8 +36,11 @@ enum class CardPayoutService(
         minAmount = 20, maxAmount = 1000, decimalsAllowed = false, gstPercent = 8) {
         // Dhiraagu rounds the GST to 2 places and credits the rest
         override fun creditedAfterGst(amount: BigDecimal): BigDecimal =
-            amount - DhiraaguReloadClient.gstOf(amount.setScale(0, RoundingMode.DOWN).toInt())
-    };
+            amount - DhiraaguPaymentClient.gstOf(amount.setScale(0, RoundingMode.DOWN).toInt())
+    },
+    // Easy Pay sets no limits of its own: any amount with up to 2 decimals, no GST
+    DHIRAAGU_BILL("Dhiraagu Bill Pay", "Dhiraagu · Bill Pay", R.drawable.dhiraagu_logo,
+        minAmount = 1, maxAmount = null, decimalsAllowed = true, gstPercent = null);
 }
 
 /**
@@ -78,7 +81,11 @@ class CardPayoutTransferHandler(
     fun typesFor(result: CarrierLookup.Result, cards: Set<String>): List<TransferType.Card> {
         if (cards.isEmpty()) return emptyList()
         return buildList {
-            if (result.dhiraagu.type == DhiraaguClient.CustType.RELOAD) add(CardPayoutService.DHIRAAGU_RELOAD)
+            when (result.dhiraagu.type) {
+                DhiraaguClient.CustType.RELOAD -> add(CardPayoutService.DHIRAAGU_RELOAD)
+                DhiraaguClient.CustType.BILL_PAY -> add(CardPayoutService.DHIRAAGU_BILL)
+                DhiraaguClient.CustType.UNSUPPORTED -> {}
+            }
         }.map { TransferType.Card(it, result.ownerName, cards) }
     }
 
@@ -144,7 +151,9 @@ class CardPayoutTransferHandler(
                 runCatching {
                     val txnId = when (svc) {
                         CardPayoutService.DHIRAAGU_RELOAD ->
-                            DhiraaguReloadClient().createBmlTransaction(number, amount.intValueExact())
+                            DhiraaguPaymentClient().createReloadTransaction(number, amount.intValueExact())
+                        CardPayoutService.DHIRAAGU_BILL ->
+                            DhiraaguPaymentClient().createBillPayTransaction(number, amount)
                     }
                     BmlMerchantTxnClient().fetchPayPage(txnId)
                 }