Add stock sell vertical slice with cash recovery and snapshot pricing (3d-26)

1 files changed, 179 insertions, 0 deletions

diff --git a/src/FundLab.Api/App.fs b/src/FundLab.Api/App.fs
index 44a9afe..896a2c4 100644
--- a/src/FundLab.Api/App.fs
+++ b/src/FundLab.Api/App.fs
@@ -160,6 +160,20 @@ type StockPositionsResponse =
         positions: StockPositionResponse list
     }
 
+type StockSellResponse =
+    {
+        id: Guid
+        fundId: Guid
+        instrumentCode: string
+        stockName: string option
+        quantity: string
+        price: string
+        feeAmount: string
+        proceeds: string
+        executedAt: string
+        isSynthetic: bool
+    }
+
 type BondTradeResponse =
     {
         id: Guid
@@ -599,6 +613,20 @@ module App =
             isSynthetic = trade.IsSynthetic
         }
 
+    let private stockSellResponse (sell: StockSellRecord) : StockSellResponse =
+        {
+            id = sell.Id
+            fundId = sell.FundId
+            instrumentCode = sell.InstrumentCode
+            stockName = sell.StockName
+            quantity = decimalText sell.Quantity
+            price = decimalText sell.Price
+            feeAmount = cashText sell.FeeAmount
+            proceeds = cashText sell.Proceeds
+            executedAt = timestampText sell.ExecutedAt
+            isSynthetic = sell.IsSynthetic
+        }
+
     let private stockPositionResponse (position: StockPositionRecord) : StockPositionResponse =
         {
             instrumentCode = position.InstrumentCode
@@ -928,6 +956,51 @@ module App =
         with
         | :? JsonException -> Error "request body must be valid JSON"
 
+    let private parseStockSellCommand (body: string) : Result<StockSellCommand, string> =
+        try
+            use document = JsonDocument.Parse(body)
+            let root = document.RootElement
+
+            if root.ValueKind <> JsonValueKind.Object then
+                Error "request body must be a JSON object"
+            else
+                match tryStringProperty root "instrumentCode" with
+                | None -> Error "instrumentCode is required"
+                | Some code ->
+                    if code.Trim().Length <> 6 || not (code.Trim() |> Seq.forall Char.IsDigit) then
+                        Error "instrumentCode must contain exactly six digits"
+                    else
+                        match tryStringProperty root "quantity" with
+                        | None -> Error "quantity is required"
+                        | Some quantityText ->
+                            match tryDecimal "quantity" quantityText with
+                            | Error message -> Error message
+                            | Ok quantity ->
+                                match tryStringProperty root "feeAmount" with
+                                | None ->
+                                    Ok
+                                        {
+                                            InstrumentCode = code.Trim()
+                                            StockName = tryStringProperty root "stockName"
+                                            Quantity = quantity
+                                            Price = 0m
+                                            FeeAmount = 0m
+                                        }
+                                | Some feeText ->
+                                    match tryDecimal "feeAmount" feeText with
+                                    | Error message -> Error message
+                                    | Ok fee ->
+                                        Ok
+                                            {
+                                                InstrumentCode = code.Trim()
+                                                StockName = tryStringProperty root "stockName"
+                                                Quantity = quantity
+                                                Price = 0m
+                                                FeeAmount = fee
+                                            }
+        with
+        | :? JsonException -> Error "request body must be valid JSON"
+
     let private parseBondTradeCommand (body: string) : Result<BondTradeCommand, string> =
         try
             use document = JsonDocument.Parse(body)
@@ -2149,6 +2222,111 @@ module App =
                 with _ ->
                     errorResponse 500 "PERSISTENCE_ERROR" "stock position persistence failed" next ctx
 
+    let private completeStockSell
+        (repository: FundRepository)
+        (fundId: Guid)
+        (idempotencyKey: string)
+        (command: StockSellCommand)
+        next
+        ctx
+        =
+        task {
+            try
+                match repository.CreateStockSell(idempotencyKey, fundId, command) with
+                | StockSellWriteResult.StockSellCreated sell ->
+                    return! invokeHandler (setStatusCode 201 >=> json (stockSellResponse sell)) next ctx
+                | StockSellWriteResult.StockSellReplayed sell ->
+                    return! invokeHandler (json (stockSellResponse sell)) next ctx
+                | StockSellWriteResult.StockSellIdempotencyConflict ->
+                    return! invokeHandler (errorResponse 409 "IDEMPOTENCY_CONFLICT" "idempotency key was used with a different request") next ctx
+                | StockSellWriteResult.StockSellInsufficientHoldings message ->
+                    return! invokeHandler (errorResponse 400 "INSUFFICIENT_STOCK_HOLDINGS" message) next ctx
+                | StockSellWriteResult.StockSellInvalid message ->
+                    return! invokeHandler (errorResponse 400 "INVALID_STOCK_SELL_REQUEST" message) next ctx
+                | StockSellWriteResult.StockSellFundNotFound ->
+                    return! invokeHandler (errorResponse 404 "FUND_NOT_FOUND" "fund was not found") next ctx
+            with _ ->
+                return! invokeHandler (errorResponse 500 "PERSISTENCE_ERROR" "stock sale persistence failed") next ctx
+        }
+
+    let private createStockSell (repository: FundRepository) (probes: MarketProbes option) (fundIdText: string) : HttpHandler =
+        fun next ctx ->
+            task {
+                match Guid.TryParse fundIdText with
+                | false, _ ->
+                    return! invokeHandler (errorResponse 400 "INVALID_STOCK_SELL_REQUEST" "fund id must be a UUID") next ctx
+                | true, fundId ->
+                    use reader = new StreamReader(ctx.Request.Body)
+                    let! body = reader.ReadToEndAsync()
+                    let idempotencyKey = ctx.Request.Headers["Idempotency-Key"].ToString()
+
+                    match parseStockSellCommand body with
+                    | Error message ->
+                        return! invokeHandler (errorResponse 400 "INVALID_STOCK_SELL_REQUEST" message) next ctx
+                    | Ok command ->
+                        let asOfDate = ConfirmationPolicy.eventDateFor DateTimeOffset.UtcNow
+
+                        let snapshotPrice =
+                            try
+                                repository.GetLatestSnapshots(fundId, "stock", asOfDate)
+                                |> Map.tryFind command.InstrumentCode
+                                |> Option.map (fun snapshot -> snapshot.Price)
+                            with _ ->
+                                None
+
+                        let existingName =
+                            try
+                                repository.GetStockPositions fundId
+                                |> List.tryFind (fun position -> position.InstrumentCode = command.InstrumentCode)
+                                |> Option.bind (fun position -> position.StockName)
+                            with _ ->
+                                None
+
+                        let resolveName (candidate: string option) =
+                            match candidate with
+                            | Some name when not (String.IsNullOrWhiteSpace name) -> Some name
+                            | _ -> existingName
+
+                        match snapshotPrice with
+                        | Some price ->
+                            return!
+                                completeStockSell
+                                    repository
+                                    fundId
+                                    idempotencyKey
+                                    { command with Price = price; StockName = resolveName command.StockName }
+                                    next
+                                    ctx
+                        | None ->
+                            match probes with
+                            | None ->
+                                return!
+                                    invokeHandler
+                                        (marketDataError (MarketDataCollectorUnavailable "stock quote probe is not configured"))
+                                        next
+                                        ctx
+                            | Some configured ->
+                                match configured.StockQuotes.GetQuote(command.InstrumentCode, ctx.RequestAborted) with
+                                | Error failure -> return! invokeHandler (marketDataError failure) next ctx
+                                | Ok quote ->
+                                    match quote.Price with
+                                    | None ->
+                                        return!
+                                            invokeHandler
+                                                (marketDataError (InvalidMarketDataPayload "stock quote did not include a price"))
+                                                next
+                                                ctx
+                                    | Some price ->
+                                        return!
+                                            completeStockSell
+                                                repository
+                                                fundId
+                                                idempotencyKey
+                                                { command with Price = price; StockName = resolveName quote.Name }
+                                                next
+                                                ctx
+            }
+
     let private createBondTrade (repository: FundRepository) (probes: MarketProbes option) (fundIdText: string) : HttpHandler =
         fun next ctx ->
             task {
@@ -2584,6 +2762,7 @@ module App =
                 POST >=> routef "/funds/%s/investment-plans" (createInvestmentPlan repository)
                 GET >=> routef "/funds/%s/investment-plans" (getInvestmentPlans repository)
                 POST >=> routef "/funds/%s/stock-trades" (createStockTrade repository probes)
+                POST >=> routef "/funds/%s/stock-sells" (createStockSell repository probes)
                 GET >=> routef "/funds/%s/stock-positions" (getStockPositions repository)
                 POST >=> routef "/funds/%s/bond-trades" (createBondTrade repository probes)
                 GET >=> routef "/funds/%s/bond-positions" (getBondPositions repository)