path: root/src/LivingVillage.Desktop/Game.fs

namespace LivingVillage.Desktop

open System
open Microsoft.Xna.Framework
open Microsoft.Xna.Framework.Graphics
open Microsoft.Xna.Framework.Input
open LivingVillage.Kernel
open LivingVillage.Kernel.Sim
open LivingVillage.Desktop.ChineseText
open LivingVillage.Desktop.VillagePresentation

module PixelText =
    let private glyphs =
        [ 'A', [| "01110"; "10001"; "10001"; "11111"; "10001"; "10001"; "10001" |]
          'B', [| "11110"; "10001"; "10001"; "11110"; "10001"; "10001"; "11110" |]
          'C', [| "01111"; "10000"; "10000"; "10000"; "10000"; "10000"; "01111" |]
          'D', [| "11110"; "10001"; "10001"; "10001"; "10001"; "10001"; "11110" |]
          'E', [| "11111"; "10000"; "10000"; "11110"; "10000"; "10000"; "11111" |]
          'F', [| "11111"; "10000"; "10000"; "11110"; "10000"; "10000"; "10000" |]
          'G', [| "01111"; "10000"; "10000"; "10111"; "10001"; "10001"; "01111" |]
          'H', [| "10001"; "10001"; "10001"; "11111"; "10001"; "10001"; "10001" |]
          'I', [| "11111"; "00100"; "00100"; "00100"; "00100"; "00100"; "11111" |]
          'J', [| "00111"; "00010"; "00010"; "00010"; "00010"; "10010"; "01100" |]
          'K', [| "10001"; "10010"; "10100"; "11000"; "10100"; "10010"; "10001" |]
          'L', [| "10000"; "10000"; "10000"; "10000"; "10000"; "10000"; "11111" |]
          'M', [| "10001"; "11011"; "10101"; "10101"; "10001"; "10001"; "10001" |]
          'N', [| "10001"; "11001"; "10101"; "10011"; "10001"; "10001"; "10001" |]
          'O', [| "01110"; "10001"; "10001"; "10001"; "10001"; "10001"; "01110" |]
          'P', [| "11110"; "10001"; "10001"; "11110"; "10000"; "10000"; "10000" |]
          'Q', [| "01110"; "10001"; "10001"; "10001"; "10101"; "10010"; "01101" |]
          'R', [| "11110"; "10001"; "10001"; "11110"; "10100"; "10010"; "10001" |]
          'S', [| "01111"; "10000"; "10000"; "01110"; "00001"; "00001"; "11110" |]
          'T', [| "11111"; "00100"; "00100"; "00100"; "00100"; "00100"; "00100" |]
          'U', [| "10001"; "10001"; "10001"; "10001"; "10001"; "10001"; "01110" |]
          'V', [| "10001"; "10001"; "10001"; "10001"; "10001"; "01010"; "00100" |]
          'W', [| "10001"; "10001"; "10001"; "10101"; "10101"; "11011"; "10001" |]
          'X', [| "10001"; "10001"; "01010"; "00100"; "01010"; "10001"; "10001" |]
          'Y', [| "10001"; "10001"; "01010"; "00100"; "00100"; "00100"; "00100" |]
          'Z', [| "11111"; "00001"; "00010"; "00100"; "01000"; "10000"; "11111" |]
          '0', [| "01110"; "10001"; "10011"; "10101"; "11001"; "10001"; "01110" |]
          '1', [| "00100"; "01100"; "00100"; "00100"; "00100"; "00100"; "01110" |]
          '2', [| "01110"; "10001"; "00001"; "00010"; "00100"; "01000"; "11111" |]
          '3', [| "11110"; "00001"; "00001"; "01110"; "00001"; "00001"; "11110" |]
          '4', [| "00010"; "00110"; "01010"; "10010"; "11111"; "00010"; "00010" |]
          '5', [| "11111"; "10000"; "10000"; "11110"; "00001"; "00001"; "11110" |]
          '6', [| "01110"; "10000"; "10000"; "11110"; "10001"; "10001"; "01110" |]
          '7', [| "11111"; "00001"; "00010"; "00100"; "01000"; "01000"; "01000" |]
          '8', [| "01110"; "10001"; "10001"; "01110"; "10001"; "10001"; "01110" |]
          '9', [| "01110"; "10001"; "10001"; "01111"; "00001"; "00001"; "01110" |]
          ('-', [| "00000"; "00000"; "00000"; "11111"; "00000"; "00000"; "00000" |])
          ('.', [| "00000"; "00000"; "00000"; "00000"; "00000"; "00110"; "00110" |])
          ('=', [| "00000"; "11111"; "00000"; "00000"; "11111"; "00000"; "00000" |])
          (':', [| "00000"; "00110"; "00110"; "00000"; "00110"; "00110"; "00000" |])
          (';', [| "00000"; "00110"; "00110"; "00000"; "00110"; "00100"; "01000" |])
          ('/', [| "00001"; "00010"; "00010"; "00100"; "01000"; "01000"; "10000" |])
          ('>', [| "10000"; "01000"; "00100"; "00010"; "00100"; "01000"; "10000" |])
          ('?', [| "01110"; "10001"; "00001"; "00010"; "00100"; "00000"; "00100" |]) ]
         |> Map.ofList

    let isRenderable (text: string) : bool =
        not (isNull text)
        && text
           |> Seq.forall (fun character ->
               character = ' '
               || Map.containsKey (Char.ToUpperInvariant character) glyphs
                || CjkGlyphAtlas.contains character)

    let draw (spriteBatch: SpriteBatch) (pixel: Texture2D) (cjkAtlas: Texture2D) (x: int) (y: int) (scale: int) (color: Color) (text: string) =
        let mutable cursor = x
        for character in text.ToUpperInvariant() do
            if character = ' ' then
                cursor <- cursor + (4 * scale)
            elif CjkGlyphAtlas.sourceRectangle character |> Option.isSome then
                let source = CjkGlyphAtlas.sourceRectangle character |> Option.get
                let glyphPixels = 8 * scale
                spriteBatch.Draw(
                    cjkAtlas,
                    Rectangle(cursor, y, glyphPixels, glyphPixels),
                    Nullable<Rectangle>(source),
                    color)
                cursor <- cursor + glyphPixels
            else
                match glyphs |> Map.tryFind character with
                | Some rows ->
                    for row in 0 .. rows.Length - 1 do
                        for column in 0 .. rows.[row].Length - 1 do
                            if rows.[row].[column] = '1' then
                                spriteBatch.Draw(pixel, Rectangle(cursor + column * scale, y + row * scale, scale, scale), color)
                    cursor <- cursor + (6 * scale)
                | None ->
                    // Unsupported characters are intentionally blank, never a fake glyph.
                    cursor <- cursor + (6 * scale)

type LivingVillageGame() as this =
    inherit Game()

    let autoplay = Environment.GetEnvironmentVariable("LV_AUTOPLAY") = "1"
    let autoplayFlow = Environment.GetEnvironmentVariable("LV_AUTOPLAY_FLOW") = "1"
    let sampleMode = Environment.GetEnvironmentVariable("LV_AUTOPLAY_SAMPLE") = "1"
    let daylightAutoplay = Environment.GetEnvironmentVariable("LV_AUTOPLAY_DAYLIGHT") = "1"
    let automated = autoplay || autoplayFlow
    let modeName =
        if sampleMode then "sample"
        elif autoplayFlow then "autoplay-flow"
        elif autoplay then "autoplay"
        else "keyboard"
    let configuredStepsPerFrame =
        match Environment.GetEnvironmentVariable("LV_STEPS_PER_FRAME") with
        | null | "" -> 1
        | s ->
            match Int32.TryParse s with
            | true, n when n > 0 -> n
            | _ -> 1
    let initialSimulationControl, initialLegacyStepsPerFrame =
        SimulationControl.initialForConfiguredSteps configuredStepsPerFrame
    let startSimulationControl =
        if sampleMode then SimulationControl.setSpeed TwoX initialSimulationControl else initialSimulationControl
    let savePath =
        match Environment.GetEnvironmentVariable("LV_SAVE_PATH") with
        | null | "" -> "living-village.save"
        | path -> path
    let graphics = new GraphicsDeviceManager(this)
    let mutable spriteBatch = Unchecked.defaultof<SpriteBatch>
    let mutable artTextures = Unchecked.defaultof<VillageArt.ArtTextures>
    let mutable cjkAtlas = Unchecked.defaultof<Texture2D>
    let mutable pixel = Unchecked.defaultof<Texture2D>
    let renderPlan = VillageArt.sampleRenderPlan ()
    let createInitialWorld () =
        WorldBootstrap.initialWorldForDaylight daylightAutoplay 42UL Sim.npcCount
    let mutable world = createInitialWorld ()
    let mutable camera = Vector2.Zero
    let mutable avatarFacing = VillageArt.SouthFacing
    let mutable fpsFrames = 0
    let mutable fpsSeconds = 0.0
    let mutable prevKb = Unchecked.defaultof<KeyboardState>
    let mutable relationView = false
    let mutable relationSnapshot: float32[,] option = None
    let mutable m5View = M5Interaction.initial
    let mutable simulationControl = startSimulationControl
    let mutable legacyStepsPerFrame = (if sampleMode then None else initialLegacyStepsPerFrame)
    let mutable menu = MenuState.create startSimulationControl false
    let mutable autoplayFrames = 0
    let mutable flowStep = 0
    let mutable flowHold = 0
    let mutable sampleState = SampleScript.initial
    let mutable hudClock = 0L
    let mutable hudStatus = ""
    let mutable hudStatusAt = 0L
    let mutable pauseHelpControl: SimulationControl option = None
    let recordMode = Environment.GetEnvironmentVariable("LV_AUTOPLAY_RECORD") = "1"
    let mutable recordIndex = 0

    do
        graphics.PreferredBackBufferWidth <- 1280
        graphics.PreferredBackBufferHeight <- 720
        graphics.SynchronizeWithVerticalRetrace <- true
        this.IsFixedTimeStep <- true
        this.TargetElapsedTime <- TimeSpan.FromTicks(TimeSpan.TicksPerSecond / 60L)
        this.Window.Title <- ChineseText.copy.SceneTitle
        printfn $"mode={modeName} seed=42"
        printfn "controls=WASD move E interact 1-6 choose Q observe Tab needs C chronicle L relations P pause F1/F2/F3 speed F6 save F7 load Esc close/exit"
    member private this.CenterCamera() =
        let viewport = this.GraphicsDevice.Viewport
        let vw = float32 viewport.Width
        let vh = float32 viewport.Height
        let worldW = float32 (Sim.mapWidthTiles * Sim.tilePixels)
        let worldH = float32 (Sim.mapHeightTiles * Sim.tilePixels)
        let half = float32 Sim.tilePixels / 2.0f
        let x = MathHelper.Clamp(world.Avatar.Pos.X + half - vw / 2.0f, 0.0f, max 0.0f (worldW - vw))
        let y = MathHelper.Clamp(world.Avatar.Pos.Y + half - vh / 2.0f, 0.0f, max 0.0f (worldH - vh))
        camera <- Vector2(x, y)

    member private this.ResetWorldView() =
        relationView <- false
        relationSnapshot <- None
        avatarFacing <- VillageArt.SouthFacing
        m5View <- M5Interaction.refreshPrompt world M5Interaction.initial
        this.CenterCamera()

    member private this.StartNewGame() =
        world <- createInitialWorld ()
        this.ResetWorldView()
        menu <- menu |> MenuState.setCurrentWorld true |> MenuState.enterGame
        printfn $"new-game=ok seed=42 npcs={Sim.npcCount}"

    member private this.SaveWorld (prefix: string) : bool =
        try
            WorldSave.saveToFile savePath world
            m5View <- { m5View with Status = "save succeeded"; StatusTick = Some world.Tick }
            printfn $"{prefix}=ok path={savePath} tick={world.Tick}"
            true
        with
        | ex ->
            m5View <- { m5View with Status = "save failed"; StatusTick = Some world.Tick }
            printfn $"{prefix}=error path={savePath} message={ex.Message}"
            false

    member private this.LoadWorld (prefix: string) : Result<int64, string> =
        match WorldSave.loadFromFile savePath with
        | Ok nextWorld ->
            world <- nextWorld
            this.ResetWorldView()
            printfn $"{prefix}=ok path={savePath} tick={world.Tick}"
            Ok world.Tick
        | Error failure ->
            printfn $"{prefix}=error path={savePath} message={failure}"
            Error failure

    member private this.OpenMainMenu() =
        relationView <- false
        relationSnapshot <- None
        m5View <- M5Interaction.initial
        menu <- menu |> MenuState.setCurrentWorld true |> MenuState.openMain
        printfn $"menu=open tick={world.Tick}"

    member private this.ApplyMenuCommand (command: MenuCommand) =
        match command with
        | NoCommand -> ()
        | ContinueGame ->
            menu <- menu |> MenuState.setCurrentWorld true |> MenuState.enterGame
            printfn $"continue=ok tick={world.Tick}"
        | StartNewGame -> this.StartNewGame()
        | LoadGame ->
            match this.LoadWorld "load" with
            | Ok _ ->
                menu <- menu |> MenuState.setCurrentWorld true |> MenuState.enterGame
            | Error failure ->
                menu <- menu |> MenuState.showLoadError failure
        | ApplySettings nextControl ->
            simulationControl <- nextControl
            legacyStepsPerFrame <- None
            menu <- menu |> MenuState.setSettings nextControl
            printfn $"simulation={M6Presentation.clockLabel simulationControl}"
        | ExitGame ->
            printfn "menu=exit"
            this.Exit()

    member private this.DispatchMenuInput (input: MenuInput) =
        let nextMenu, command = MenuState.update input menu
        menu <- nextMenu
        this.ApplyMenuCommand command

    member private this.UpdateMenu (pressed: Keys -> bool) =
        let pressedAny (keys: Keys list) = keys |> List.exists pressed
        let input =
            if pressedAny [ Keys.Up; Keys.W ] then Some Up
            elif pressedAny [ Keys.Down; Keys.S ] then Some Down
            elif pressed Keys.Enter then Some Confirm
            elif pressed Keys.Escape then Some Back
            else None
        match input with
        | Some nextInput -> this.DispatchMenuInput nextInput
        | None when (autoplay || sampleMode) && not autoplayFlow && menu.Page = MainMenu && not menu.HasCurrentWorld ->
            autoplayFrames <- autoplayFrames + 1
            if autoplayFrames >= 15 then
                this.DispatchMenuInput Confirm
        | None -> ()

    member private this.RunSampleMode () =
        let stageBefore = sampleState.Stage
        let positionBefore = world.Avatar.Pos
        let nextWorld, nextView, nextState = SampleScript.runFrame world m5View sampleState
        if nextWorld.Avatar.Pos <> positionBefore then
            avatarFacing <- VillageArt.facingAfterMovement positionBefore nextWorld.Avatar.Pos avatarFacing
        world <- nextWorld
        m5View <- nextView
        sampleState <- nextState
        this.CenterCamera()
        if nextState.Stage <> stageBefore then
            printfn $"sample stage={nextState.Stage} tick={nextWorld.Tick} pos=({nextWorld.Avatar.Pos.X:F0},{nextWorld.Avatar.Pos.Y:F0})"
            if nextState.Stage = SampleScript.SampleComplete then
                printfn (if nextState.TimedOut then "sample result=timeout" else "sample result=ok")
                this.Exit()

    member private this.UpdatePlaying (gameTime: GameTime) (kb: KeyboardState) (pressed: Keys -> bool) (pressedAny: Keys list -> bool) =
        if sampleMode then
            this.RunSampleMode()
        else
            this.UpdatePlayingManual gameTime kb pressed pressedAny

    member private this.UpdatePlayingManual (gameTime: GameTime) (kb: KeyboardState) (pressed: Keys -> bool) (pressedAny: Keys list -> bool) =
        let mutable loadFailed = false
        let mutable leftGame = false
        let lPressed = pressed Keys.L
        let escapePressed = pressed Keys.Escape
        if pressed Keys.P then
            if m5View.Panel = WorldPanel then
                let helpState, pausedControl = MenuState.enterPauseHelp simulationControl menu
                menu <- helpState
                pauseHelpControl <- Some simulationControl
                simulationControl <- pausedControl
                printfn $"help=pause-open simulation={M6Presentation.clockLabel simulationControl}"
        if pressed Keys.F1 then
            simulationControl <- SimulationControl.setSpeed OneX simulationControl
            legacyStepsPerFrame <- None
            menu <- MenuState.setSettings simulationControl menu
            printfn $"simulation={M6Presentation.clockLabel simulationControl}"
        if pressed Keys.F2 then
            simulationControl <- SimulationControl.setSpeed TwoX simulationControl
            legacyStepsPerFrame <- None
            menu <- MenuState.setSettings simulationControl menu
            printfn $"simulation={M6Presentation.clockLabel simulationControl}"
        if pressed Keys.F3 then
            simulationControl <- SimulationControl.setSpeed FiveX simulationControl
            legacyStepsPerFrame <- None
            menu <- MenuState.setSettings simulationControl menu
            printfn $"simulation={M6Presentation.clockLabel simulationControl}"
        if pressed Keys.F6 then
            this.SaveWorld "save" |> ignore
        if pressed Keys.F7 then
            match this.LoadWorld "load" with
            | Ok _ -> menu <- MenuState.setCurrentWorld true menu
            | Error failure ->
                menu <- menu |> MenuState.setCurrentWorld true |> MenuState.showLoadError failure
                loadFailed <- true
        if not loadFailed && escapePressed then
            if m5View.Panel <> WorldPanel then
                let nextWorld, nextView = M5Interaction.apply ClosePanel world m5View
                world <- nextWorld
                m5View <- nextView
                printfn $"m5 panel={M5Interaction.panelName m5View} status={m5View.Status} tick={world.Tick}"
            elif relationView then
                relationView <- false
                relationSnapshot <- None
                printfn $"relation view=off tick={world.Tick}"
            else
                this.OpenMainMenu()
                leftGame <- true
        if not loadFailed && not leftGame then
            if lPressed && M5Interaction.worldInputAllowed m5View then
                relationView <- not relationView
                if relationView then relationSnapshot <- Some(Sim.relationMatrix world)
                let state = if relationView then "on" else "off"
                printfn $"relation view={state} tick={world.Tick}"
            let m5Command =
                if M5Interaction.worldInputAllowed m5View && pressed Keys.E then Some Interact
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D1; Keys.NumPad1 ] then Some Intent1
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D2; Keys.NumPad2 ] then Some Intent2
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D3; Keys.NumPad3 ] then Some Intent3
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D4; Keys.NumPad4 ] then Some Intent4
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D5; Keys.NumPad5 ] then Some Intent5
                elif m5View.Panel = DialoguePanel && pressedAny [ Keys.D6; Keys.NumPad6 ] then Some Intent6
                elif pressed Keys.Q then Some Observe
                elif pressed Keys.Tab then Some ToggleNeeds
                elif pressed Keys.C then Some ShowChronicle
                else None
            match m5Command with
            | Some command ->
                let nextWorld, nextView = M5Interaction.apply command world m5View
                world <- nextWorld
                m5View <- nextView
                printfn $"m5 panel={M5Interaction.panelName m5View} status={m5View.Status} tick={world.Tick}"
            | None -> ()
            let panelOpen = m5View.Panel <> WorldPanel
            if not relationView && not panelOpen then
                let input =
                    if automated then
                        let t = float32 world.Tick
                        { MoveX = MathF.Sin(t / 60.0f) * 0.8f
                          MoveY = MathF.Cos(t / 90.0f) * 0.6f }
                    else
                        { MoveX =
                            (if kb.IsKeyDown(Keys.D) then 1.0f
                             elif kb.IsKeyDown(Keys.A) then -1.0f
                             else 0.0f)
                          MoveY =
                            (if kb.IsKeyDown(Keys.S) then 1.0f
                             elif kb.IsKeyDown(Keys.W) then -1.0f
                             else 0.0f) }
                let ts = { Input = input }
                let stepCount = SimulationControl.stepsPerFrameWithLegacy legacyStepsPerFrame simulationControl
                if stepCount > 0 then
                    for _ in 1 .. stepCount do
                        let previousPosition = world.Avatar.Pos
                        world <- Sim.step ts world
                        avatarFacing <- VillageArt.facingAfterMovement previousPosition world.Avatar.Pos avatarFacing
                this.CenterCamera()
            m5View <- M5Interaction.refreshPrompt world m5View

    member private this.RunAutoplayFlow() =
        let moveDown count =
            for _ in 1 .. count do
                this.DispatchMenuInput Down
        match flowStep with
        | 0 ->
            printfn "flow=main-menu"
            flowStep <- 50
        | 50 when menu.Page = MainMenu ->
            flowHold <- flowHold + 1
            if flowHold >= 60 then
                flowHold <- 0
                this.DispatchMenuInput Confirm
                printfn "flow=new-game"
                flowStep <- 1
        | 50 ->
            printfn "flow=new-game"
            flowStep <- 1
        | 1 when menu.Page = Playing ->
            this.OpenMainMenu()
            printfn "flow=return-menu"
            flowStep <- 2
        | 2 when menu.Page = MainMenu ->
            moveDown 3
            this.DispatchMenuInput Confirm
            printfn "flow=settings=open"
            this.DispatchMenuInput Down
            this.DispatchMenuInput Confirm
            this.DispatchMenuInput Back
            printfn "flow=settings=back"
            flowStep <- 3
        | 3 when menu.Page = MainMenu ->
            moveDown 4
            this.DispatchMenuInput Confirm
            printfn "flow=controls=open"
            flowStep <- 30
        | 30 ->
            flowHold <- flowHold + 1
            if flowHold >= 60 || menu.Page <> Controls then
                flowHold <- 0
                flowStep <- 31
        | 31 ->
            this.DispatchMenuInput Back
            printfn "flow=controls=back"
            flowStep <- 4
        | 4 when menu.Page = MainMenu ->
            this.DispatchMenuInput Confirm
            this.SaveWorld "flow=save" |> ignore
            flowStep <- 5
        | 5 when menu.Page = Playing ->
            this.LoadWorld "flow=load" |> ignore
            flowStep <- 6
        | 6 ->
            this.OpenMainMenu()
            printfn "flow=exit"
            this.Exit()
            flowStep <- 7
        | _ -> ()

    override this.Initialize() =
        base.Initialize()
        prevKb <- Keyboard.GetState()

    override _.LoadContent() =
        spriteBatch <- new SpriteBatch(this.GraphicsDevice)
        artTextures <- VillageArt.loadTextures this.GraphicsDevice
        cjkAtlas <- CjkGlyphAtlas.load this.GraphicsDevice
        pixel <- new Texture2D(this.GraphicsDevice, 1, 1)
        pixel.SetData([| Color.White |])

    override _.UnloadContent() =
        if not (isNull artTextures.TileAtlas) then artTextures.TileAtlas.Dispose()
        if not (isNull artTextures.CharacterAtlas) then artTextures.CharacterAtlas.Dispose()
        if not (isNull artTextures.InteriorAtlas) then artTextures.InteriorAtlas.Dispose()
        if not (isNull cjkAtlas) then cjkAtlas.Dispose()
        if not (isNull pixel) then pixel.Dispose()
        if not (isNull spriteBatch) then spriteBatch.Dispose()

    override this.Update(gameTime: GameTime) =
        let kb = Keyboard.GetState()
        let pressed (key: Keys) = kb.IsKeyDown(key) && not (prevKb.IsKeyDown(key))
        let pressedAny (keys: Keys list) = keys |> List.exists pressed
        if autoplayFlow then
            this.RunAutoplayFlow()
        elif menu.Page = Playing then
            this.UpdatePlaying gameTime kb pressed pressedAny
        else
            this.UpdateMenu pressed
        match pauseHelpControl with
        | Some original when menu.Page = Playing ->
            let _, restoredControl = MenuState.exitPauseHelp original menu
            simulationControl <- restoredControl
            pauseHelpControl <- None
            printfn $"help=pause-close simulation={M6Presentation.clockLabel simulationControl}"
        | _ -> ()
        hudClock <- hudClock + 1L
        if m5View.Status <> hudStatus then
            hudStatus <- m5View.Status
            hudStatusAt <- hudClock
        fpsFrames <- fpsFrames + 1
        fpsSeconds <- fpsSeconds + gameTime.ElapsedGameTime.TotalSeconds
        if fpsSeconds >= 1.0 then
            let fps = float fpsFrames / fpsSeconds
            fpsFrames <- 0
            fpsSeconds <- 0.0
            printfn $"fps={fps:F1} tick={world.Tick} pos=({world.Avatar.Pos.X:F0},{world.Avatar.Pos.Y:F0})"
        prevKb <- kb

    member private this.DrawLine (a: Vector2) (b: Vector2) (thickness: float32) (color: Color) =
        let d = b - a
        let len = d.Length()
        if len > 1.0f then
            let angle = MathF.Atan2(d.Y, d.X)
            spriteBatch.Draw(pixel, a, System.Nullable(), color, angle, Vector2.Zero, Vector2(len, thickness), SpriteEffects.None, 0.0f)

    member private this.DrawRelationView() =
        let profile = M6Presentation.profileAtTick world.Tick
        this.GraphicsDevice.Clear(profile.Background)
        let viewport = this.GraphicsDevice.Viewport
        let vw = float32 viewport.Width
        let vh = float32 viewport.Height
        let mapW = float32 (Sim.mapWidthTiles * Sim.tilePixels)
        let mapH = float32 (Sim.mapHeightTiles * Sim.tilePixels)
        let margin = 48.0f
        let scale = min ((vw - 2.0f * margin) / mapW) ((vh - 2.0f * margin) / mapH)
        let ox = (vw - mapW * scale) / 2.0f
        let oy = (vh - mapH * scale) / 2.0f
        let toScreen (p: Vec2) : Vector2 = Vector2(ox + p.X * scale, oy + p.Y * scale)
        spriteBatch.Begin()
        match relationSnapshot with
        | Some m ->
            let n = Array2D.length1 m
            for i in 0 .. n - 1 do
                for j in i + 1 .. n - 1 do
                    let r = m.[i, j]
                    if abs r > Sim.relationThreshold then
                        let a = toScreen world.Npcs.[i].Pos
                        let b = toScreen world.Npcs.[j].Pos
                        let color = if r > 0.0f then Color.LimeGreen else Color.IndianRed
                        let thickness = Sim.clamp (1.5f + 3.0f * abs r) 1.5f 12.0f
                        this.DrawLine a b thickness color
            for npc in world.Npcs do
                let p = toScreen npc.Pos
                spriteBatch.Draw(pixel, Rectangle(int p.X - 5, int p.Y - 5, 10, 10), Color.Cyan)
        | None -> ()
        spriteBatch.End()

    override this.Draw(gameTime: GameTime) =
        if menu.Page <> Playing then
            this.DrawMenu()
        elif relationView then
            this.DrawRelationView()
            this.DrawM5Overlay()
        else
            this.DrawWorldView()
        if recordMode && sampleMode then
            recordIndex <- recordIndex + 1
            if recordIndex % 25 = 0 then
                let directory = "/tmp/lv-p5-prompt"
                System.IO.Directory.CreateDirectory directory |> ignore
                let width, height =
                    this.GraphicsDevice.PresentationParameters.BackBufferWidth,
                    this.GraphicsDevice.PresentationParameters.BackBufferHeight
                let buffer = Array.zeroCreate<Color> (width * height)
                this.GraphicsDevice.GetBackBufferData<Color>(buffer)
                use texture = new Texture2D(this.GraphicsDevice, width, height)
                texture.SetData(buffer)
                let path = sprintf "%s/rec-frame-%04d.png" directory recordIndex
                use stream = System.IO.File.Create(path)
                texture.SaveAsPng(stream, width, height)

    member private this.DrawMenu() =
        let viewport = this.GraphicsDevice.Viewport
        let width = viewport.Width
        let height = viewport.Height
        let layout = TitleScreen.layout width height
        let panelWidth = layout.PanelWidth
        let panelX = layout.PanelX
        let panelY = layout.PanelY
        let contentRows =
            match menu.Page with
            | MainMenu -> MenuState.items menu |> List.length
            | Settings -> MenuState.settings.Length
            | Controls -> MenuState.controlRows.Length
            | LoadError -> 4
            | Playing -> 0
        let rowHeight = if menu.Page = Controls then 25 else layout.MenuLineHeight
        let panelY =
            if menu.Page = Controls then layout.ControlsPanelY else layout.PanelY
        let panelHeight =
            min (height - panelY - 16)
                (max layout.PanelHeight (120 + contentRows * rowHeight + 48))
        let innerX = layout.MenuX
        let textScale = 2
        let lineHeight = layout.MenuLineHeight
        let selectedColor = Color(245, 222, 120)
        let textColor = Color(210, 226, 220)
        let mutedColor = Color(140, 170, 170)
        let drawText (x: int) (y: int) (color: Color) (text: string) =
            PixelText.draw spriteBatch pixel cjkAtlas x y textScale color text
        let drawSelection (index: int) (label: string) (y: int) =
            let selected = index = menu.Selected
            let cursor, labelRect = TitleScreen.selectionRects layout index
            if selected then
                PixelText.draw spriteBatch pixel cjkAtlas cursor.X cursor.Y textScale selectedColor ">"
            else
                PixelText.draw spriteBatch pixel cjkAtlas cursor.X cursor.Y textScale mutedColor " "
            PixelText.draw spriteBatch pixel cjkAtlas labelRect.X labelRect.Y textScale (if selected then selectedColor else textColor) label
        spriteBatch.Begin()

        // Layered dusk gradient: sky bands darken toward the horizon, never a flat block.
        let bandCount = List.length layout.SkyBands
        let bandHeight = height / bandCount
        List.iteri (fun index (band: TitleScreen.ColorRgb) ->
            let y0 = index * bandHeight
            let y1 = if index = bandCount - 1 then height else y0 + bandHeight
            spriteBatch.Draw(pixel, Rectangle(0, y0, width, y1 - y0), Color(band.R, band.G, band.B))) layout.SkyBands

        // Jiangnan skyline: eave tiles continuously, ridge tiles rising above them.
        List.iteri (fun column slot ->
            let x = column * Sim.tilePixels
            let source = VillageArt.atlasTileRectangle slot
            if slot = fst TitleScreen.roofSlots then
                spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, layout.RidgeY, Sim.tilePixels, Sim.tilePixels), source, Color.White)
            spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, layout.EaveY, Sim.tilePixels, Sim.tilePixels), VillageArt.atlasTileRectangle (snd TitleScreen.roofSlots), Color.White))
            layout.RoofTileSlots

        // Water band drawn from the atlas water tile, reflecting the skyline above.
        for row in layout.WaterRows do
            for x in 0 .. Sim.tilePixels .. width - 1 do
                spriteBatch.Draw(artTextures.TileAtlas, Rectangle(x, row, Sim.tilePixels, Sim.tilePixels), VillageArt.atlasTileRectangle TitleScreen.waterSlot, Color(150, 170, 178))

        // Lantern glows along the water bank.
        let lanternColor, lanternHalo = TitleScreen.lanternColors
        for (lx, ly) in layout.Lanterns do
            spriteBatch.Draw(pixel, Rectangle(lx - 8, ly - 8, 24, 24), Color(lanternHalo.R, lanternHalo.G, lanternHalo.B, 70))
            spriteBatch.Draw(pixel, Rectangle(lx - 3, ly - 5, 8, 10), Color(lanternColor.R, lanternColor.G, lanternColor.B))
            spriteBatch.Draw(pixel, Rectangle(lx - 1, ly - 7, 4, 2), Color(90, 60, 40))
            spriteBatch.Draw(pixel, Rectangle(lx - 2, ly + 5, 6, 2), Color(90, 60, 40))

        // Title: large CJK atlas glyphs with a soft shadow for readability.
        PixelText.draw spriteBatch pixel cjkAtlas (layout.TitleX + 4) (layout.TitleY + 4) layout.TitleScale (Color(12, 20, 28)) layout.TitleText
        PixelText.draw spriteBatch pixel cjkAtlas layout.TitleX layout.TitleY layout.TitleScale (Color(235, 246, 232)) layout.TitleText

        // Menu panel floats over the lower half; translucent so the scene layers stay visible.
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY, panelWidth, panelHeight), Color(11, 19, 27, 200))
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY, panelWidth, 4), Color(92, 180, 190))
        let contentY = panelY + 60
        let headingY = panelY + 20
        match menu.Page with
        | MainMenu ->
            drawText innerX headingY mutedColor (ChineseText.menuHeading MainMenuHeading)
            MenuState.items menu
            |> List.iteri (fun index item -> drawSelection index (MenuState.itemLabel item) (contentY + index * lineHeight))
            drawText innerX (panelY + panelHeight - 40) mutedColor "UP DOWN 选择 ENTER 确认"
        | Settings ->
            drawText innerX headingY mutedColor (ChineseText.menuHeading SettingsHeading)
            MenuState.settings
            |> List.iteri (fun index setting -> drawSelection index (MenuState.settingsLabel setting) (contentY + index * lineHeight))
            drawText innerX (panelY + panelHeight - 72) mutedColor (sprintf "当前 %s" (M6Presentation.clockLabel menu.Settings))
            drawText innerX (panelY + panelHeight - 40) mutedColor "ENTER 应用 ESC 返回"
        | Controls ->
            drawText innerX headingY mutedColor (ChineseText.menuHeading ControlsHeading)
            MenuState.controlRows
            |> List.iteri (fun index row ->
                let keyRect, actionRect = TitleScreen.controlRowRects layout index
                PixelText.draw spriteBatch pixel cjkAtlas keyRect.X keyRect.Y textScale textColor row.Keys
                PixelText.draw spriteBatch pixel cjkAtlas actionRect.X actionRect.Y textScale textColor row.Action)
            drawText innerX (panelY + panelHeight - 40) mutedColor "ESC 返回"
        | LoadError ->
            drawText innerX headingY (Color(240, 130, 120)) "读取失败"
            let message = menu.Error |> Option.defaultValue "暂无存档"
            let visible = if message.Length > 24 then message.Substring(0, 24) else message
            drawText innerX contentY textColor visible
            drawText innerX (contentY + lineHeight * 2) mutedColor "ENTER ESC 返回"
        | Playing -> ()
        spriteBatch.End()

    member private this.DrawWorldView() =
        let profile = M6Presentation.profileAtTick world.Tick
        let viewport = this.GraphicsDevice.Viewport
        this.GraphicsDevice.Clear(profile.Background)
        spriteBatch.Begin()
        match m5View.HomeMode with
        | Inside _ ->
            VillageArt.drawInterior spriteBatch pixel artTextures viewport.Width viewport.Height renderPlan.Interior profile.WorldTint
            let interiorAvatarSpec = VillageArt.avatarSpriteSpec avatarFacing world.Tick
            VillageArt.drawInteriorCharacter spriteBatch artTextures viewport.Width viewport.Height world.Avatar.Pos interiorAvatarSpec profile.WorldTint
        | Outside ->
            VillageArt.drawWorld
                spriteBatch
                artTextures
                camera
                viewport.Width
                viewport.Height
                renderPlan
                world.Tick
                profile.WorldTint

            let avatarSpec = VillageArt.avatarSpriteSpec avatarFacing world.Tick
            VillageArt.drawCharacter spriteBatch artTextures camera world.Avatar.Pos avatarSpec profile.WorldTint

            for npc in world.Npcs do
                let spec = VillageArt.npcSpriteSpecAtTarget npc.Id npc.Pos npc.Mind.Target world.Tick
                VillageArt.drawCharacter spriteBatch artTextures camera npc.Pos spec profile.WorldTint
        spriteBatch.End()

        // Contextual floating prompt over the unique target; same CJK atlas font path as the HUD.
        if m5View.Panel = M5Panel.WorldPanel && menu.Page = Playing then
            match m5View.Prompt, m5View.PromptTargetPos with
            | Some text, Some targetPos ->
                let scale = 2
                let rect = FloatingPrompt.layout viewport.Width viewport.Height targetPos.X targetPos.Y camera.X camera.Y scale text
                spriteBatch.Begin()
                spriteBatch.Draw(pixel, Rectangle(rect.X - 6, rect.Y - 5, rect.Width + 12, rect.Height + 8), Color(15, 19, 25, 200))
                spriteBatch.Draw(pixel, Rectangle(rect.X - 6, rect.Y - 5, rect.Width + 12, 2), Color(92, 180, 190))
                PixelText.draw spriteBatch pixel cjkAtlas rect.X rect.Y scale (Color(240, 250, 240)) text
                spriteBatch.End()
            | _ -> ()
        this.DrawM5Overlay()

    member private this.DrawM5Overlay() =
        let viewport = this.GraphicsDevice.Viewport
        let textScale = 2
        let lineHeight = 18
        let profile = M6Presentation.profileAtTick world.Tick
        let timeLine = sprintf "时间 %s %s" (M6Presentation.dayNightLabel profile.Mode) (M6Presentation.clockLabel simulationControl)
        let persistentLines =
            timeLine :: (m5View.Prompt |> Option.toList)
        let dialogueLines =
            match m5View.Panel, m5View.Menu with
            | DialoguePanel, Some menu ->
                menu.Options
                |> List.mapi (fun index intent -> sprintf "%d %s" (index + 1) (M5Interaction.intentLine intent))
                |> fun options -> [ sprintf "互动：村民 %d" (M5Interaction.menuNpcNumber menu) ] @ options
            | _ -> []
        let statusView = { m5View with StatusTick = Some hudStatusAt }
        let statusLine = M5Interaction.transientStatusLine hudClock statusView |> Option.toList
        let allLines = persistentLines @ dialogueLines @ statusLine
        let cornerLines = M5Interaction.cornerStatusLines world
        let panelWidth = min 360 (max 1 (viewport.Width - 32))
        let maxLines = max 1 ((viewport.Height - 48) / lineHeight)
        let lines = allLines |> List.truncate maxLines
        let panelHeight = lines.Length * lineHeight + 24
        let panelX = 16
        let panelY = max 16 (viewport.Height - panelHeight - 16)
        let panel = Rectangle(panelX, panelY, panelWidth, panelHeight)
        let innerX = panelX + 12
        let innerWidth = max 1 (panelWidth - 24)
        let maxChars = max 1 (innerWidth / (6 * textScale))
        spriteBatch.Begin()
        spriteBatch.Draw(pixel, panel, Color(15, 19, 25, 160))
        spriteBatch.Draw(pixel, Rectangle(panelX, panelY, panelWidth, 3), Color(92, 180, 190))
        lines
        |> List.iteri (fun index line ->
            let visible = if line.Length > maxChars then line.Substring(0, maxChars) else line
            let color = if index = 0 then Color(220, 235, 220) else Color(190, 205, 210)
            PixelText.draw spriteBatch pixel cjkAtlas innerX (panelY + 12 + index * lineHeight) textScale color visible)

        // Minimal top-right status strip: day counter + real money/energy values.
        let cornerWidth = 232
        let cornerHeight = List.length cornerLines * lineHeight + 20
        let cornerX = viewport.Width - cornerWidth - 16
        let cornerY = 16
        spriteBatch.Draw(pixel, Rectangle(cornerX, cornerY, cornerWidth, cornerHeight), Color(15, 19, 25, 150))
        spriteBatch.Draw(pixel, Rectangle(cornerX, cornerY, cornerWidth, 3), Color(92, 180, 190))
        cornerLines
        |> List.iteri (fun index line ->
            let visible = if line.Length > maxChars then line.Substring(0, maxChars) else line
            PixelText.draw spriteBatch pixel cjkAtlas (cornerX + 10) (cornerY + 10 + index * lineHeight) textScale (Color(220, 235, 220)) visible)
        spriteBatch.End()