fix(bot): improve calculated purchase confirmation flow

apps/bot/src/openai-purchase-interpreter.ts

@@ -1,12 +1,15 @@
 import { extractOpenAiResponseText, parseJsonFromResponseText } from './openai-responses'
 
 export type PurchaseInterpretationDecision = 'purchase' | 'clarification' | 'not_purchase'
+export type PurchaseInterpretationAmountSource = 'explicit' | 'calculated'
 
 export interface PurchaseInterpretation {
   decision: PurchaseInterpretationDecision
   amountMinor: bigint | null
   currency: 'GEL' | 'USD' | null
   itemDescription: string | null
+  amountSource?: PurchaseInterpretationAmountSource | null
+  calculationExplanation?: string | null
   confidence: number
   parserMode: 'llm'
   clarificationQuestion: string | null
@@ -31,6 +34,8 @@ interface OpenAiStructuredResult {
   amountMinor: string | null
   currency: 'GEL' | 'USD' | null
   itemDescription: string | null
+  amountSource: PurchaseInterpretationAmountSource | null
+  calculationExplanation: string | null
   confidence: number
   clarificationQuestion: string | null
 }
@@ -53,61 +58,15 @@ function normalizeCurrency(value: string | null): 'GEL' | 'USD' | null {
   return value === 'GEL' || value === 'USD' ? value : null
 }
 
-function toMinorUnits(rawAmount: string): bigint {
-  const normalized = rawAmount.replace(',', '.')
-  const [wholePart, fractionalPart = ''] = normalized.split('.')
-  const cents = fractionalPart.padEnd(2, '0').slice(0, 2)
-
-  return BigInt(`${wholePart}${cents}`)
-}
-
-function extractLikelyMoneyAmountMinor(rawText: string): bigint | null {
-  const moneyCueMatches = Array.from(
-    rawText.matchAll(
-      /(?:за|выложил(?:а)?|отдал(?:а)?|заплатил(?:а)?|потратил(?:а)?|стоит|стоило)\s*(\d+(?:[.,]\d{1,2})?)/giu
-    )
-  )
-  if (moneyCueMatches.length === 1) {
-    const rawAmount = moneyCueMatches[0]?.[1]
-    if (rawAmount) {
-      return toMinorUnits(rawAmount)
-    }
-  }
-
-  const explicitMoneyMatches = Array.from(
-    rawText.matchAll(
-      /(\d+(?:[.,]\d{1,2})?)\s*(?:₾|gel|lari|лари|usd|\$|доллар(?:а|ов)?|кровн\p{L}*)/giu
-    )
-  )
-  if (explicitMoneyMatches.length === 1) {
-    const rawAmount = explicitMoneyMatches[0]?.[1]
-    if (rawAmount) {
-      return toMinorUnits(rawAmount)
-    }
-  }
-
-  const standaloneMatches = Array.from(rawText.matchAll(/\b(\d+(?:[.,]\d{1,2})?)\b/gu))
-  if (standaloneMatches.length === 1) {
-    const rawAmount = standaloneMatches[0]?.[1]
-    if (rawAmount) {
-      return toMinorUnits(rawAmount)
-    }
-  }
-
-  return null
-}
-
-function resolveAmountMinor(input: { rawText: string; amountMinor: bigint | null }): bigint | null {
-  if (input.amountMinor === null) {
+function normalizeAmountSource(
+  value: PurchaseInterpretationAmountSource | null,
+  amountMinor: bigint | null
+): PurchaseInterpretationAmountSource | null {
+  if (amountMinor === null) {
     return null
   }
 
-  const explicitAmountMinor = extractLikelyMoneyAmountMinor(input.rawText)
-  if (explicitAmountMinor === null) {
-    return input.amountMinor
-  }
-
-  return explicitAmountMinor === input.amountMinor * 100n ? explicitAmountMinor : input.amountMinor
+  return value === 'calculated' ? 'calculated' : 'explicit'
 }
 
 function normalizeConfidence(value: number): number {
@@ -183,7 +142,11 @@ export function createOpenAiPurchaseInterpreter(
               'Decide whether the latest message is a real shared purchase, needs clarification, or is not a shared purchase at all.',
               `The household default currency is ${options.defaultCurrency}. If a real purchase clearly omits currency, use ${options.defaultCurrency}.`,
               'amountMinor must be expressed in minor currency units. Example: 350 GEL -> 35000, 3.50 GEL -> 350, 45 lari -> 4500.',
+              'If the user gives quantity and per-item price, compute the total spend and return that total in amountMinor.',
+              'Set amountSource to "explicit" when the user directly states the total amount, or "calculated" when you compute it from quantity x price or similar arithmetic.',
+              'When amountSource is "calculated", also return a short calculationExplanation in the user message language, such as "5 × 6 lari = 30 lari".',
               'Ignore item quantities like rolls, kilograms, or layers unless they are clearly the money amount.',
+              'Treat colloquial completed-buy phrasing like "взял", "сходил и взял", or "сторговался до X" as a completed purchase when the message reports a real buy fact.',
               'If recent messages from the same sender are provided, treat them as clarification context for the latest message.',
               'If the latest message is a complete standalone purchase on its own, ignore the earlier clarification context.',
               'If the latest message answers a previous clarification, combine it with the earlier messages to resolve the purchase.',
@@ -233,6 +196,18 @@ export function createOpenAiPurchaseInterpreter(
                 itemDescription: {
                   anyOf: [{ type: 'string' }, { type: 'null' }]
                 },
+                amountSource: {
+                  anyOf: [
+                    {
+                      type: 'string',
+                      enum: ['explicit', 'calculated']
+                    },
+                    { type: 'null' }
+                  ]
+                },
+                calculationExplanation: {
+                  anyOf: [{ type: 'string' }, { type: 'null' }]
+                },
                 confidence: {
                   type: 'number',
                   minimum: 0,
@@ -247,6 +222,8 @@ export function createOpenAiPurchaseInterpreter(
                 'amountMinor',
                 'currency',
                 'itemDescription',
+                'amountSource',
+                'calculationExplanation',
                 'confidence',
                 'clarificationQuestion'
               ]
@@ -286,11 +263,10 @@ export function createOpenAiPurchaseInterpreter(
       return null
     }
 
-    const amountMinor = resolveAmountMinor({
-      rawText,
-      amountMinor: asOptionalBigInt(parsedJson.amountMinor)
-    })
+    const amountMinor = asOptionalBigInt(parsedJson.amountMinor)
     const itemDescription = normalizeOptionalText(parsedJson.itemDescription)
+    const amountSource = normalizeAmountSource(parsedJson.amountSource, amountMinor)
+    const calculationExplanation = normalizeOptionalText(parsedJson.calculationExplanation)
     const currency = resolveMissingCurrency({
       decision: parsedJson.decision,
       amountMinor,
@@ -315,6 +291,8 @@ export function createOpenAiPurchaseInterpreter(
       amountMinor,
       currency,
       itemDescription,
+      amountSource,
+      calculationExplanation: amountSource === 'calculated' ? calculationExplanation : null,
       confidence: normalizeConfidence(parsedJson.confidence),
       parserMode: 'llm',
       clarificationQuestion: decision === 'clarification' ? clarificationQuestion : null