namespace LivingVillage.Kernel.Tests

open System
open System.IO
open Microsoft.VisualStudio.TestTools.UnitTesting
open LivingVillage.Kernel
open LivingVillage.Kernel.Sim

module private DailyTaskHarness =

    let taskOf (template: Occupation.TaskTemplateId) (state: Occupation.TaskState) : Occupation.DailyTask =
        { TemplateId = template
          TargetNpc = None
          TargetTile = None
          OfferedTick = 0L
          DueTick = Sim.ticksPerDay - 1L
          State = state }

    let accepted (template: Occupation.TaskTemplateId) : Occupation.DailyTask =
        Occupation.acceptTask (taskOf template Occupation.Offered)

    let worldWithAnnal () : World =
        let world = Sim.initialWorldN 7UL 2
        match Sim.trade { Buyer = NpcId 0; Seller = NpcId 1; Item = Food; Quantity = 1 } world with
        | TradeSucceeded next -> next
        | TradeRejected (failure, _) -> Assert.Fail($"trade rejected: {failure}"); Unchecked.defaultof<World>

    let taskForDay (day: int64) : Occupation.DailyTask =
        (Occupation.dailyTaskOf 42UL 7UL day Occupation.Fisher).Value |> Occupation.acceptTask

    let withTempSave (action: string -> unit) =
        let id = Guid.NewGuid().ToString("N")
        let path = Path.Combine(Path.GetTempPath(), $"living-village-p11-{id}.save")
        try
            action path
        finally
            if File.Exists path then File.Delete path

[<TestClass>]
type DailyTaskTests () =

    // ---- §3 生成：hash(seed ^ occupationSeed, dayIndex) mod |pool|（splitmix 同源）----

    [<TestMethod>]
    member _.TaskHashFollowsSplitmixOverSeedXorOccupationSeed () =
        Assert.AreEqual<uint64>(0xF7E9F3F88CC04AD6UL, Occupation.taskHash 42UL 7UL 0L)
        Assert.AreEqual<uint64>(0xFB624BD98F2BE6C4UL, Occupation.taskHash 42UL 7UL 1L)
        Assert.AreEqual<uint64>(0x87FC3F1DAC740225UL, Occupation.taskHash 42UL 7UL 2L)
        Assert.AreEqual<uint64>(0xDA258F1151868B40UL, Occupation.taskHash 42UL 7UL 3L)
        Assert.AreEqual<uint64>(0x02D114B7ABDD7A1FUL, Occupation.taskHash 4242UL 99UL 0L)

    [<TestMethod>]
    member _.EveryOccupationPoolIsNonEmptyAndFarmFisherKeepThree () =
        Assert.AreEqual(
            [ Occupation.DeliverGrain; Occupation.HelpWork; Occupation.TillSoil ],
            Occupation.taskPoolOf Occupation.Farmer)
        Assert.AreEqual(
            [ Occupation.NightCatch; Occupation.SellFish; Occupation.MarketInquiry ],
            Occupation.taskPoolOf Occupation.Fisher)
        Assert.AreEqual(
            [ Occupation.BuyGoods; Occupation.Resell ],
            Occupation.taskPoolOf Occupation.Peddler)
        Assert.AreEqual(
            [ Occupation.ObserveNotes; Occupation.ReasonDebate ],
            Occupation.taskPoolOf Occupation.Scholar)

    [<TestMethod>]
    member _.GeneratedTasksStayInPoolAndRepeatDeterministically () =
        for seed, occ in [ (42UL, 7UL); (7UL, 42UL); (123456789UL, 555UL) ] do
            for kind in Occupation.all do
                let pool = Occupation.taskPoolOf kind
                for day in 0L .. 299L do
                    let task = (Occupation.dailyTaskOf seed occ day kind).Value
                    Assert.IsTrue(pool |> List.contains task.TemplateId, $"day {day} escaped the pool")
                    let again = (Occupation.dailyTaskOf seed occ day kind).Value
                    Assert.AreEqual<Occupation.DailyTask>(task, again)
                let distinct =
                    [ 0L .. 299L ]
                    |> List.map (fun day -> (Occupation.dailyTaskOf seed occ day kind).Value.TemplateId)
                    |> Set.ofList
                Assert.IsTrue(distinct.Count >= 2, "300 days must not pin a single template")

    [<TestMethod>]
    member _.PeddlerAndScholarGenerateTheirOwnDailyTasks () =
        for kind in [ Occupation.Peddler; Occupation.Scholar ] do
            for day in 0L .. 59L do
                let task = (Occupation.dailyTaskOf 42UL 7UL day kind).Value
                Assert.IsTrue(Occupation.taskPoolOf kind |> List.contains task.TemplateId)
        Assert.AreEqual<Occupation.TaskTemplateId>(
            Occupation.BuyGoods,
            (Occupation.dailyTaskOf 42UL 7UL 0L Occupation.Peddler).Value.TemplateId)
        Assert.AreEqual<Occupation.TaskTemplateId>(
            Occupation.ObserveNotes,
            (Occupation.dailyTaskOf 42UL 7UL 0L Occupation.Scholar).Value.TemplateId)

    [<TestMethod>]
    member _.TaskWindowCoversExactlyOneDayStartingOffered () =
        let task = (Occupation.dailyTaskOf 42UL 7UL 3L Occupation.Farmer).Value
        Assert.AreEqual<int64>(3L * Sim.ticksPerDay, task.OfferedTick)
        Assert.AreEqual<int64>(4L * Sim.ticksPerDay - 1L, task.DueTick)
        Assert.AreEqual<Occupation.TaskState>(Occupation.Offered, task.State)
        Assert.AreEqual<int64>(3L, Occupation.dayIndexOf (3L * Sim.ticksPerDay))
        Assert.AreEqual<int64>(3L, Occupation.dayIndexOf (4L * Sim.ticksPerDay - 1L))

    [<TestMethod>]
    member _.TaskTemplateChineseNamesMatchDesignTable () =
        Assert.AreEqual<string>("送粮", Occupation.taskNameOf Occupation.DeliverGrain)
        Assert.AreEqual<string>("帮工", Occupation.taskNameOf Occupation.HelpWork)
        Assert.AreEqual<string>("翻土", Occupation.taskNameOf Occupation.TillSoil)
        Assert.AreEqual<string>("夜捕", Occupation.taskNameOf Occupation.NightCatch)
        Assert.AreEqual<string>("卖渔", Occupation.taskNameOf Occupation.SellFish)
        Assert.AreEqual<string>("询价", Occupation.taskNameOf Occupation.MarketInquiry)
        Assert.AreEqual<string>("收货", Occupation.taskNameOf Occupation.BuyGoods)
        Assert.AreEqual<string>("转卖", Occupation.taskNameOf Occupation.Resell)
        Assert.AreEqual<string>("观察记事", Occupation.taskNameOf Occupation.ObserveNotes)
        Assert.AreEqual<string>("论理", Occupation.taskNameOf Occupation.ReasonDebate)

    // ---- §3 状态机 Offered|Active|Done|Failed ----

    [<TestMethod>]
    member _.AcceptMovesOfferedToActiveOnly () =
        let offered = DailyTaskHarness.taskOf Occupation.HelpWork Occupation.Offered
        let active = Occupation.acceptTask offered
        Assert.AreEqual<Occupation.TaskState>(Occupation.Active, active.State)
        Assert.AreEqual<Occupation.TaskState>(Occupation.Active, (Occupation.acceptTask active).State)
        let finished = { active with State = Occupation.Done }
        Assert.AreEqual<Occupation.TaskState>(Occupation.Done, (Occupation.acceptTask finished).State)
        let failed = { active with State = Occupation.Failed }
        Assert.AreEqual<Occupation.TaskState>(Occupation.Failed, (Occupation.acceptTask failed).State)

    [<TestMethod>]
    member _.SellFishCompletesOnlyOnPlayerFishSales () =
        let active = DailyTaskHarness.accepted Occupation.SellFish
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal (Occupation.Traded(playerId, Fish, 1)) active).State)
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Active,
            (Occupation.applySignal (Occupation.Traded(playerId, Spice, 1)) active).State)
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Active,
            (Occupation.applySignal (Occupation.Traded(NpcId 2, Fish, 4)) active).State)
        let offered = DailyTaskHarness.taskOf Occupation.SellFish Occupation.Offered
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Offered,
            (Occupation.applySignal (Occupation.Traded(playerId, Fish, 1)) offered).State)

    [<TestMethod>]
    member _.DeliverGrainCompletesOnlyOnPlayerFoodGiveaways () =
        let active = DailyTaskHarness.accepted Occupation.DeliverGrain
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal (Occupation.Traded(playerId, Food, 3)) active).State)
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Active,
            (Occupation.applySignal (Occupation.Traded(playerId, Fish, 1)) active).State)
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Active,
            (Occupation.applySignal (Occupation.Traded(NpcId 5, Food, 1)) active).State)

    [<TestMethod>]
    member _.HelpWorkAndTillSoilRespectOptionalTargets () =
        let wildcard = DailyTaskHarness.accepted Occupation.HelpWork
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal (Occupation.Dialogued(NpcId 4)) wildcard).State)
        let targeted =
            { DailyTaskHarness.accepted Occupation.HelpWork with TargetNpc = Some(NpcId 2) }
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal (Occupation.Dialogued(NpcId 2)) targeted).State)
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Active,
            (Occupation.applySignal (Occupation.Dialogued(NpcId 4)) targeted).State)
        let untilled = DailyTaskHarness.accepted Occupation.TillSoil
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal (Occupation.ArrivedAt(1, 1)) untilled).State)
        let plotTilling =
            { DailyTaskHarness.accepted Occupation.TillSoil with TargetTile = Some(52, 38) }
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal (Occupation.ArrivedAt(52, 38)) plotTilling).State)
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Active,
            (Occupation.applySignal (Occupation.ArrivedAt(10, 10)) plotTilling).State)

    [<TestMethod>]
    member _.NightCatchAndMarketInquiryCompleteOnTheirSignals () =
        let active = DailyTaskHarness.accepted Occupation.NightCatch
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal Occupation.NightAtWater active).State)
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Active,
            (Occupation.applySignal (Occupation.Dialogued(NpcId 0)) active).State)
        let inquiring = DailyTaskHarness.accepted Occupation.MarketInquiry
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal (Occupation.Dialogued(NpcId 3)) inquiring).State)
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Active,
            (Occupation.applySignal Occupation.NightAtWater inquiring).State)

    [<TestMethod>]
    member _.DoneAndFailedAreTerminalStates () =
        let finished = { DailyTaskHarness.accepted Occupation.SellFish with State = Occupation.Done }
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Done,
            (Occupation.applySignal (Occupation.Traded(playerId, Fish, 1)) finished).State)
        let failed = { DailyTaskHarness.accepted Occupation.SellFish with State = Occupation.Failed }
        Assert.AreEqual<Occupation.TaskState>(
            Occupation.Failed,
            (Occupation.applySignal (Occupation.Traded(playerId, Fish, 1)) failed).State)

    [<TestMethod>]
    member _.OverdueTasksFailAtDayBoundaryButNotBefore () =
        let active = DailyTaskHarness.accepted Occupation.SellFish
        Assert.AreEqual<Occupation.TaskState>(Occupation.Active, (Occupation.expireAt active.DueTick active).State)
        Assert.AreEqual<Occupation.TaskState>(Occupation.Failed, (Occupation.expireAt (active.DueTick + 1L) active).State)
        let offered = DailyTaskHarness.taskOf Occupation.SellFish Occupation.Offered
        Assert.AreEqual<Occupation.TaskState>(Occupation.Failed, (Occupation.expireAt (offered.DueTick + 1L) offered).State)
        let finished = { active with State = Occupation.Done }
        Assert.AreEqual<Occupation.TaskState>(Occupation.Done, (Occupation.expireAt (finished.DueTick + 1L) finished).State)

    // ---- §2-A 存档 v3：annals 之后追加 today task 尾段 ----

    [<TestMethod>]
    member _.SaveV3AppendsTaskTailAfterAnnalsAndRoundTrips () =
        let world = DailyTaskHarness.worldWithAnnal ()
        let state =
            { (Occupation.stateOf Occupation.Fisher) with
                TaskToken = 5
                StoryStage = 2
                Today = Some(DailyTaskHarness.taskForDay 2L) }
        DailyTaskHarness.withTempSave (fun path ->
            WorldSave.saveToFileWith (Some state) path world
            let text = File.ReadAllText path
            Assert.IsTrue(text.StartsWith("LV_WORLD_SAVE_V3"), "v3 header expected")
            let tokens = text.Split('|')
            Assert.IsTrue(tokens |> Array.exists (fun token -> token = "task-today"), "task tail marker expected")
            Assert.IsTrue(tokens |> Array.exists (fun token -> token = "backpack"), "backpack tail marker expected")
            let markerIndex = tokens |> Array.findIndex (fun token -> token = "task-today")
            let backpackIndex = tokens |> Array.findIndex (fun token -> token = "backpack")
            let lastAnnalKindIndex =
                tokens |> Array.findIndexBack (fun token -> token = "trade")
            Assert.IsTrue(markerIndex > lastAnnalKindIndex, "task tail must follow the annals segment")
            Assert.IsTrue(backpackIndex > markerIndex, "backpack tail must follow the task tail")
            Assert.AreEqual<string>("3", Array.last tokens)
            match WorldSave.loadFromFileWith path with
            | Ok (restored, Some restoredState) ->
                Assert.AreEqual<Occupation.State>(state, restoredState)
                Assert.AreEqual<string>(WorldSave.save world, WorldSave.save restored)
                Assert.AreEqual<string>(text, WorldSave.saveWith (Some restoredState) restored)
            | Ok (_, None) -> Assert.Fail("v3 with task tail must restore the occupation")
            | Error message -> Assert.Fail($"v3 task round trip failed: {message}"))

    [<TestMethod>]
    member _.SaveV3WithoutTaskCarriesOnlyBackpackTail () =
        let world = DailyTaskHarness.worldWithAnnal ()
        let state = Occupation.stateOf Occupation.Peddler
        DailyTaskHarness.withTempSave (fun path ->
            WorldSave.saveToFileWith (Some state) path world
            let text = File.ReadAllText path
            Assert.IsTrue(text.StartsWith("LV_WORLD_SAVE_V3"), "v3 header expected")
            Assert.IsFalse(text.Contains("task-today"), "no-task v3 must not carry a task tail")
            Assert.IsTrue(text.Contains("backpack"), "v3 must carry the backpack tail")
            match WorldSave.loadFromFileWith path with
            | Ok (restored, Some restoredState) ->
                Assert.AreEqual<Occupation.DailyTask option>(None, restoredState.Today)
                Assert.AreEqual<string>(text, WorldSave.saveWith (Some restoredState) restored)
            | Ok (_, None) -> Assert.Fail("v3 with kind must restore the occupation")
            | Error message -> Assert.Fail($"v3 no-task read failed: {message}"))

    [<TestMethod>]
    member _.V1AndV2SavesCarryNoTaskTail () =
        let world = Sim.initialWorld 42UL
        DailyTaskHarness.withTempSave (fun path ->
            WorldSave.saveToFile path world
            let v2Text = File.ReadAllText path
            Assert.IsTrue(v2Text.StartsWith("LV_WORLD_SAVE_V2"), "default save must stay v2")
            Assert.IsFalse(v2Text.Contains("task-today"))
            match WorldSave.loadFromFileWith path with
            | Ok (restored, occupation) ->
                Assert.AreEqual<Occupation.State option>(None, occupation)
                Assert.AreEqual<string>(v2Text, WorldSave.save restored)
            | Error message -> Assert.Fail($"v2 read failed: {message}")

            let firstPipe = v2Text.IndexOf('|')
            let secondPipe = v2Text.IndexOf('|', firstPipe + 1)
            let thirdPipe = v2Text.IndexOf('|', secondPipe + 1)
            let v1Text = "LV_WORLD_SAVE_V1" + v2Text.Substring(thirdPipe)
            File.WriteAllText(path, v1Text)
            match WorldSave.loadFromFileWith path with
            | Ok (_, occupation) -> Assert.AreEqual<Occupation.State option>(None, occupation)
            | Error message -> Assert.Fail($"v1 read failed: {message}")

            File.WriteAllText(path, WorldSave.saveWith (Some (Occupation.stateOf Occupation.Fisher)) world + "|task-today|bogus|offered|0|0|npc-none|tile-none")
            match WorldSave.loadFromFile path with
            | Ok _ -> Assert.Fail("unknown task template must be rejected")
            | Error _ -> ())

    [<TestMethod>]
    member _.TrailingGarbageAfterTaskTailIsRejected () =
        let world = DailyTaskHarness.worldWithAnnal ()
        let state = { (Occupation.stateOf Occupation.Farmer) with Today = Some(DailyTaskHarness.taskForDay 4L) }
        DailyTaskHarness.withTempSave (fun path ->
            let text = WorldSave.saveWith (Some state) world
            File.WriteAllText(path, text + "|junk")
            match WorldSave.loadFromFile path with
            | Ok _ -> Assert.Fail("trailing garbage after the task tail must be rejected")
            | Error _ -> ())

    [<TestMethod>]
    member _.TaskCarryingSavesAreByteIdenticalAcrossRuns () =
        let build () =
            let world = DailyTaskHarness.worldWithAnnal ()
            let state = { (Occupation.stateOf Occupation.Farmer) with Today = Some(DailyTaskHarness.taskForDay 9L) }
            WorldSave.saveWith (Some state) world
        Assert.AreEqual<string>(build (), build ())

    // ---- P15：货郎/书生模板完成信号、事件通道桥、当日刷新 ----

    [<TestMethod>]
    member _.PeddlerAndScholarTemplatesCompleteOnTheirSignals () =
        let buy = DailyTaskHarness.accepted Occupation.BuyGoods
        Assert.AreEqual<Occupation.TaskState>(Occupation.Done, (Occupation.applySignal (Occupation.Purchased(Food, 2)) buy).State)
        Assert.AreEqual<Occupation.TaskState>(Occupation.Active, (Occupation.applySignal (Occupation.Purchased(Food, 0)) buy).State)
        Assert.AreEqual<Occupation.TaskState>(Occupation.Active, (Occupation.applySignal (Occupation.Dialogued(NpcId 0)) buy).State)
        let resell = DailyTaskHarness.accepted Occupation.Resell
        Assert.AreEqual<Occupation.TaskState>(Occupation.Done, (Occupation.applySignal (Occupation.Traded(playerId, Spice, 1)) resell).State)
        Assert.AreEqual<Occupation.TaskState>(Occupation.Active, (Occupation.applySignal (Occupation.Traded(NpcId 2, Spice, 1)) resell).State)
        let observe = DailyTaskHarness.accepted Occupation.ObserveNotes
        Assert.AreEqual<Occupation.TaskState>(Occupation.Done, (Occupation.applySignal Occupation.Observed observe).State)
        Assert.AreEqual<Occupation.TaskState>(Occupation.Active, (Occupation.applySignal (Occupation.Dialogued(NpcId 0)) observe).State)
        let reason = DailyTaskHarness.accepted Occupation.ReasonDebate
        Assert.AreEqual<Occupation.TaskState>(Occupation.Done, (Occupation.applySignal (Occupation.Dialogued(NpcId 3)) reason).State)
        Assert.AreEqual<Occupation.TaskState>(Occupation.Active, (Occupation.applySignal Occupation.Observed reason).State)

    [<TestMethod>]
    member _.SignalBridgeIgnoresNpcInitiatedEvents () =
        let npcDialogue =
            { Tick = 5L
              Kind = DialogueEvent { Tick = 5L; Actor = NpcId 1; Target = NpcId 2; Intent = SmallTalk; Response = Friendly; Valence = 0.3f } }
        Assert.AreEqual<Occupation.TaskSignal option>(None, Occupation.signalOfInteraction npcDialogue)
        let npcTrade = { Tick = 5L; Kind = TradeEvent(NpcId 1, NpcId 2, Food, 1, 1.0f) }
        Assert.AreEqual<Occupation.TaskSignal option>(None, Occupation.signalOfInteraction npcTrade)
        let playerBuy = { Tick = 6L; Kind = TradeEvent(playerId, NpcId 2, Spice, 3, 2.0f) }
        Assert.AreEqual<Occupation.TaskSignal option>(Some(Occupation.Purchased(Spice, 3)), Occupation.signalOfInteraction playerBuy)
        let playerSell = { Tick = 7L; Kind = TradeEvent(NpcId 2, playerId, Fish, 4, 2.0f) }
        Assert.AreEqual<Occupation.TaskSignal option>(Some(Occupation.Traded(playerId, Fish, 4)), Occupation.signalOfInteraction playerSell)

    [<TestMethod>]
    member _.PlayerDialogueEventThroughExistingChannelCompletesTheDaysTask () =
        let world = Sim.initialWorldN 7UL 4
        let nearFirst = { world with Avatar = { world.Avatar with Pos = world.Npcs.[0].Pos } }
        match Sim.chooseDialogue (NpcId 0) SmallTalk nearFirst with
        | DialogueRejected (failure, _) -> Assert.Fail($"dialogue rejected: {failure}")
        | DialogueSucceeded (outcome, afterDialogue) ->
            let event = afterDialogue.Events |> List.last
            Assert.AreEqual<Sim.NpcId>(playerId, outcome.Actor)
            Assert.AreEqual<Occupation.TaskSignal option>(Some(Occupation.Dialogued(NpcId 0)), Occupation.signalOfInteraction event)
            let day =
                [ 0L .. 60L ]
                |> List.find (fun day ->
                    (Occupation.dailyTaskOf 42UL 7UL day Occupation.Farmer).Value.TemplateId = Occupation.HelpWork)
            let offered = (Occupation.dailyTaskOf 42UL 7UL day Occupation.Farmer).Value
            let notAccepted = Occupation.advanceTask event { (Occupation.stateOf Occupation.Farmer) with Today = Some offered }
            Assert.AreEqual<Occupation.TaskState>(Occupation.Offered, notAccepted.Today.Value.State)
            let active = notAccepted.Today |> Option.map Occupation.acceptTask
            let completed = Occupation.advanceTask event { notAccepted with Today = active }
            Assert.AreEqual<Occupation.TaskState>(Occupation.Done, completed.Today.Value.State)

    [<TestMethod>]
    member _.RefreshTodayKeepsSameDayFinalsAndRegeneratesOnDayChange () =
        let day0 = (Occupation.dailyTaskOf 42UL 7UL 0L Occupation.Farmer).Value
        Assert.AreEqual<Occupation.DailyTask option>(
            Some day0,
            Occupation.refreshToday 42UL 7UL Occupation.Farmer (Sim.ticksPerDay - 1L) (Some day0))
        let day1 = (Occupation.dailyTaskOf 42UL 7UL 1L Occupation.Farmer).Value
        Assert.AreEqual<Occupation.DailyTask option>(
            Some day1,
            Occupation.refreshToday 42UL 7UL Occupation.Farmer Sim.ticksPerDay (Some day0))
        let finished = { day0 with State = Occupation.Done }
        Assert.AreEqual<Occupation.DailyTask option>(
            Some finished,
            Occupation.refreshToday 42UL 7UL Occupation.Farmer 10L (Some finished))
        Assert.AreEqual<Occupation.DailyTask option>(
            Some day1,
            Occupation.refreshToday 42UL 7UL Occupation.Farmer Sim.ticksPerDay None)