Add real AKShare NAV-date probe slice (3d-12)

5 files changed, 114 insertions, 10 deletions

diff --git a/src/FundLab.Api/App.fs b/src/FundLab.Api/App.fs
index 34b4f2d..370f503 100644
--- a/src/FundLab.Api/App.fs
+++ b/src/FundLab.Api/App.fs
@@ -331,6 +331,12 @@ type MarketDataNavApiResponse =
         observations: MarketDataObservationApiResponse list
     }
 
+type MarketNavDatesApiResponse =
+    {
+        code: string
+        dates: string list
+    }
+
 module App =
     let addOptionFriendlyJson (services: IServiceCollection) =
         let settings =
@@ -1634,7 +1640,23 @@ module App =
             GET >=> routef "/instruments/%s/nav" (getNav marketData)
         ]
 
-    let private createApplicationInternal (repository: FundRepository) (marketData: IMarketDataService option) : HttpHandler =
+    let private getMarketNavDates (probe: INavDateProbe) : HttpHandler =
+        fun next ctx ->
+            let code = ctx.Request.Query["code"].ToString()
+
+            match probe.RecentNavDates(code, 5, ctx.RequestAborted) with
+            | Ok dates ->
+                json ({ code = code.Trim(); dates = dates |> List.map dateText } : MarketNavDatesApiResponse) next ctx
+            | Error failure -> marketDataError failure next ctx
+
+    let private navDateProbeRoutes (probe: INavDateProbe) =
+        [ GET >=> route "/market/nav-dates" >=> getMarketNavDates probe ]
+
+    let private createApplicationInternal
+        (repository: FundRepository)
+        (marketData: IMarketDataService option)
+        (navDateProbe: INavDateProbe option)
+        : HttpHandler =
         let apiRoutes =
             [
                 GET >=> route "/portfolio/summary" >=> emptyPortfolio
@@ -1665,6 +1687,7 @@ module App =
                 GET >=> routef "/funds/%s" (getFund repository)
             ]
             @ (marketData |> Option.map marketDataRoutes |> Option.defaultValue [])
+            @ (navDateProbe |> Option.map navDateProbeRoutes |> Option.defaultValue [])
 
         choose [
             GET >=> route "/health" >=> health
@@ -1676,7 +1699,17 @@ module App =
         ]
 
     let createApplicationWithMarketData (repository: FundRepository) (marketData: IMarketDataService) : HttpHandler =
-        createApplicationInternal repository (Some marketData)
+        createApplicationInternal repository (Some marketData) None
+
+    let createApplicationWithNavDateProbe (repository: FundRepository) (probe: INavDateProbe) : HttpHandler =
+        createApplicationInternal repository None (Some probe)
+
+    let createApplicationWithMarketDataAndProbe
+        (repository: FundRepository)
+        (marketData: IMarketDataService)
+        (probe: INavDateProbe)
+        : HttpHandler =
+        createApplicationInternal repository (Some marketData) (Some probe)
 
     let createApplication (repository: FundRepository) : HttpHandler =
-        createApplicationInternal repository None
+        createApplicationInternal repository None None
diff --git a/src/FundLab.Api/FundLab.Api.fsproj b/src/FundLab.Api/FundLab.Api.fsproj
index 04724c0..ed2c637 100644
--- a/src/FundLab.Api/FundLab.Api.fsproj
+++ b/src/FundLab.Api/FundLab.Api.fsproj
@@ -17,8 +17,9 @@
     <Compile Include="Health.fs" />
     <Compile Include="MarketData.fs" />
     <Compile Include="Persistence.fs" />
-    <Compile Include="MarketDataService.fs" />
-    <Compile Include="App.fs" />
+        <Compile Include="MarketDataService.fs" />
+        <Compile Include="NavDateProbe.fs" />
+        <Compile Include="App.fs" />
     <Compile Include="Program.fs" />
   </ItemGroup>
   <ItemGroup>
diff --git a/src/FundLab.Api/NavDateProbe.fs b/src/FundLab.Api/NavDateProbe.fs
new file mode 100644
index 0000000..0437fd8
--- /dev/null
+++ b/src/FundLab.Api/NavDateProbe.fs
@@ -0,0 +1,57 @@
+namespace FundLab.Api
+
+open System
+open System.Collections.Concurrent
+open System.Threading
+
+/// Read-only probe that returns the most recent NAV dates for a fund code.
+///
+/// This is the "real data first" seam for the market NAV-date endpoint: the only
+/// implementation talks to the AKShare collector, and there is deliberately no
+/// synthetic fallback. A failed probe surfaces as a MarketDataFailure so the API
+/// can answer 503 with the underlying reason instead of inventing dates.
+type INavDateProbe =
+    abstract RecentNavDates: code: string * limit: int * CancellationToken -> Result<DateOnly list, MarketDataFailure>
+
+/// AKShare-backed probe. Successful lookups are memoised per fund code
+/// (the F# equivalent of functools.lru_cache) so repeated UI reads during one
+/// process do not re-spawn the collector; failures are never cached.
+type AkshareNavDateProbe(collector: IMarketDataCollector) =
+    let cache = ConcurrentDictionary<string, DateOnly list>(StringComparer.Ordinal)
+
+    let isFundCode (value: string) =
+        not (String.IsNullOrWhiteSpace value)
+        && value.Length = 6
+        && value |> Seq.forall Char.IsDigit
+
+    let clip limit =
+        if limit < 1 then 1
+        elif limit > 60 then 60
+        else limit
+
+    member _.Clear() = cache.Clear()
+
+    interface INavDateProbe with
+        member _.RecentNavDates(code, limit, token) =
+            let normalized = if isNull code then "" else code.Trim()
+
+            if not (isFundCode normalized) then
+                Error(InvalidMarketDataRequest "fund code must contain exactly six digits")
+            else
+                match cache.TryGetValue normalized with
+                | true, cached -> Ok(cached |> List.truncate (clip limit))
+                | _ ->
+                    match collector.FetchNav(normalized, token) with
+                    | Error message -> Error(MarketDataCollectorUnavailable message)
+                    | Ok json ->
+                        match MarketData.parseNavPayload json with
+                        | Error message -> Error(InvalidMarketDataPayload message)
+                        | Ok payload ->
+                            let dates =
+                                payload.Observations
+                                |> List.map (fun observation -> observation.NavDate)
+                                |> List.distinct
+                                |> List.sortDescending
+
+                            cache.[normalized] <- dates
+                            Ok(dates |> List.truncate (clip limit))
diff --git a/src/FundLab.Api/Persistence.fs b/src/FundLab.Api/Persistence.fs
index 7a7ab32..6028b7c 100644
--- a/src/FundLab.Api/Persistence.fs
+++ b/src/FundLab.Api/Persistence.fs
@@ -59,6 +59,18 @@ module ConfirmationPolicy =
             let candidate = if local.TimeOfDay >= cutoffTimeOfDay then date.AddDays 1 else date
             rollToWeekday candidate
 
+    /// Calendar date used to bucket events (cash flows, holdings) on the returns
+    /// timeline. Shares the FUND_LAB_TEST_TRADE_DATE anchor with tradeDateFor so a
+    /// pinned suite does not drift when the host crosses midnight; production (no
+    /// pin) is exactly the Shanghai calendar date of the moment.
+    let eventDateFor (moment: DateTimeOffset) : DateOnly =
+        match Environment.GetEnvironmentVariable("FUND_LAB_TEST_TRADE_DATE") with
+        | value when not (String.IsNullOrWhiteSpace value) ->
+            match DateOnly.TryParseExact(value, "yyyy-MM-dd", CultureInfo.InvariantCulture, DateTimeStyles.None) with
+            | true, anchored -> anchored
+            | _ -> shanghaiDate moment
+        | _ -> shanghaiDate moment
+
     type NavQuote =
         { NavDate: DateOnly
           Nav: decimal
@@ -4867,7 +4879,7 @@ type FundRepository(connectionString: string) =
         match this.GetFund fundId with
         | None -> None
         | Some fund ->
-            let today = ConfirmationPolicy.shanghaiDate DateTimeOffset.UtcNow
+            let today = ConfirmationPolicy.eventDateFor DateTimeOffset.UtcNow
             let deposits = this.GetCapitalDeposits fundId
             let orders = this.GetSubscriptionOrders fundId
             let redemptions = this.GetRedemptionOrders fundId
@@ -4902,7 +4914,7 @@ type FundRepository(connectionString: string) =
                         |> List.map (fun observation -> observation.NavDate))
                 |> Set.ofList
 
-            let creationDate = ConfirmationPolicy.shanghaiDate fund.CreatedAt
+            let creationDate = ConfirmationPolicy.eventDateFor fund.CreatedAt
 
             let dividendCredited =
                 dividends
@@ -4926,7 +4938,7 @@ type FundRepository(connectionString: string) =
             else
                 let eventDates =
                     [ yield creationDate
-                      yield! deposits |> List.map (fun deposit -> ConfirmationPolicy.shanghaiDate deposit.CreatedAt)
+                      yield! deposits |> List.map (fun deposit -> ConfirmationPolicy.eventDateFor deposit.CreatedAt)
                       yield! orders |> List.map (fun order -> order.TradeDate)
                       yield! redemptions |> List.map (fun order -> order.TradeDate)
                       yield! dividendCredited |> List.map (fun record -> record.NavDate) ]
@@ -4964,7 +4976,7 @@ type FundRepository(connectionString: string) =
 
                 for date in dates do
                     for deposit in deposits do
-                        if ConfirmationPolicy.shanghaiDate deposit.CreatedAt = date then
+                        if ConfirmationPolicy.eventDateFor deposit.CreatedAt = date then
                             availableCash <- availableCash + deposit.Amount
                             cumulativeDeposits <- cumulativeDeposits + deposit.Amount
 
diff --git a/src/FundLab.Api/Program.fs b/src/FundLab.Api/Program.fs
index b7d0ef6..ba5936e 100644
--- a/src/FundLab.Api/Program.fs
+++ b/src/FundLab.Api/Program.fs
@@ -19,8 +19,9 @@ let main argv =
     repository.EnsureSchema()
     let collector = ProcessMarketDataCollector.FromEnvironment() :> IMarketDataCollector
     let marketData = MarketDataService(repository, collector) :> IMarketDataService
+    let navDateProbe = AkshareNavDateProbe(collector) :> INavDateProbe
 
     let app = builder.Build()
-    app.UseGiraffe(App.createApplicationWithMarketData repository marketData)
+    app.UseGiraffe(App.createApplicationWithMarketDataAndProbe repository marketData navDateProbe)
     app.Run()
     0