Pacman Maze in FunScript

[<ReflectedDefinition>]
module Program

open FunScript
open FunScript.TypeScript

let maze = "\
##/------------7/------------7##,\
##|............|!............|##,\
##|./__7./___7.|!./___7./__7.|##,\
##|o|  !.|   !.|!.|   !.|  !o|##,\
##|.L--J.L---J.LJ.L---J.L--J.|##,\
##|..........................|##,\
##|./__7./7./______7./7./__7.|##,\
##|.L--J.|!.L--7/--J.|!.L--J.|##,\
##|......|!....|!....|!......|##,\
##L____7.|L__7 |! /__J!./____J##,\
#######!.|/--J LJ L--7!.|#######,\
#######!.|!          |!.|#######,\
#######!.|! /__==__7 |!.|#######,\
-------J.LJ |      ! LJ.L-------,\
########.   | **** !   .########,\
_______7./7 |      ! /7./_______,\
#######!.|! L______J |!.|#######,\
#######!.|!          |!.|#######,\
#######!.|! /______7 |!.|#######,\
##/----J.LJ L--7/--J LJ.L----7##,\
##|............|!............|##,\
##|./__7./___7.|!./___7./__7.|##,\
##|.L-7!.L---J.LJ.L---J.|/-J.|##,\
##|o..|!.......<>.......|!..o|##,\
##L_7.|!./7./______7./7.|!./_J##,\
##/-J.LJ.|!.L--7/--J.|!.LJ.L-7##,\
##|......|!....|!....|!......|##,\
##|./____JL__7.|!./__JL____7.|##,\
##|.L--------J.LJ.L--------J.|##,\
##|..........................|##,\
##L--------------------------J##".Split(',')

let tl = [|
    0b00000000
    0b00000000
    0b00000000
    0b00000000
    0b00000011
    0b00000100
    0b00001000
    0b00001000|]
let top = [|
    0b00000000
    0b00000000
    0b00000000
    0b00000000
    0b11111111
    0b00000000
    0b00000000
    0b00000000|]
let tr = [|
    0b00000000
    0b00000000
    0b00000000
    0b00000000
    0b11000000
    0b00100000
    0b00010000
    0b00010000|]
let left = [|
    0b00001000
    0b00001000
    0b00001000
    0b00001000
    0b00001000
    0b00001000
    0b00001000
    0b00001000|]
let blank = [|
    0b00000000
    0b00000000
    0b00000000
    0b00000000
    0b00000000
    0b00000000
    0b00000000
    0b00000000|]
let right = [|
    0b00010000
    0b00010000
    0b00010000
    0b00010000
    0b00010000
    0b00010000
    0b00010000
    0b00010000|]
let bl = [|
    0b00001000
    0b00001000
    0b00000100
    0b00000011
    0b00000000
    0b00000000
    0b00000000
    0b00000000|]
let bottom = [|
    0b00000000
    0b00000000
    0b00000000
    0b11111111
    0b00000000
    0b00000000
    0b00000000
    0b00000000|]
let br = [|
    0b00010000
    0b00010000
    0b00100000
    0b11000000
    0b00000000
    0b00000000
    0b00000000
    0b00000000|]
let door = [|
    0b00000000
    0b00000000
    0b00000000
    0b00000000
    0b11111111
    0b00000000
    0b00000000
    0b00000000|]
let pill = [|
    0b00000000
    0b00000000
    0b00000000
    0b00011000
    0b00011000
    0b00000000
    0b00000000
    0b00000000|]
let power = [|
    0b00000000
    0b00011000
    0b00111100
    0b01111110
    0b01111110
    0b00111100
    0b00011000
    0b00000000|]

type Brush = Blue | Yellow

let toTile c =
    match c with
    | '=' -> door, Blue
    | '_' -> top, Blue
    | '|' -> left, Blue
    | '!' -> right, Blue
    | '/' -> tl, Blue
    | '7' -> tr, Blue
    | 'L' -> bl, Blue
    | 'J' -> br, Blue
    | '-' -> bottom, Blue
    | '.' -> pill, Yellow
    | 'o' -> power, Yellow
    | _ -> blank, Blue


[<JSEmit("return {0} << {1};")>]
let ShiftLeft(x:int,n:int) : int = failwith "never"

[<JSEmit("return {0} & {1};")>]
let And(a:int,b:int) : int = failwith "never"

let draw f (lines:int[]) =
    let width = 8
    lines |> Array.iteri (fun y line ->
        let line = line
        for x = 0 to width-1 do
            let bit = ShiftLeft(1, width - 1 - x)
            let pattern = And(line,bit)
            if pattern <> 0 then f (x,y)
    )

type ts = Api<"../Typings/lib.d.ts">

type Context(context:ts.CanvasRenderingContext2D) =
    member __.createBrush(r,g,b,a) =
        let id = context.createImageData(float 1,float 1)
        let d = id.data
        d.[0] <- float r; d.[1] <- float g; d.[2] <- float b; d.[3] <- float a
        id
    member __.plot(brush,x,y) =
        context.putImageData(brush, float x, float y)

let main() =
    let map = unbox<ts.HTMLCanvasElement>(ts.document.createElement("canvas"))
    map.width <- 256.
    map.height <- 256.
    let context = map.getContext("2d")
    context.fillStyle <- "rgb(0,0,0)"
    context.fillRect (0., 0. , 256., 256.);
    let context = Context(context)
    let blue = context.createBrush (63,63,255,255)
    let yellow = context.createBrush (255,255,0,255)
    let lines = maze
    for y = 0 to lines.Length-1 do
        let line = lines.[y]
        for x = 0 to line.Length-1 do
            let c = line.[x]
            let tile, color = toTile c
            let brush = match color with Blue -> blue | Yellow -> yellow
            let f (x',y') = context.plot(brush, x*8 + x', (y+1)*8 + y')
            draw f tile
    let b = context
    let canvas = unbox<ts.HTMLCanvasElement>(ts.document.getElementById("canvas"))
    let context = canvas.getContext("2d")
    canvas.width <- 1000.
    canvas.height <- 800.
    context.drawImage(unbox<ts.HTMLElement>(map), 0., 0.)
    context.drawImage(unbox<ts.HTMLElement>(map), 256., 0.)
    context.drawImage(unbox<ts.HTMLElement>(map), 256., 256.)
    context.drawImage(unbox<ts.HTMLElement>(map), 0., 256.)

do Runtime.Run(directory="Web", components=Interop.Components.all)