module Games.TicTacToe exposing (..)

{-| This module exposes a library for the simple game of tic-tac-toe.
-}

import Color
import Element exposing (Element)
import Json.Decode as D
import Layout
import Pixels exposing (Pixels)
import Quantity exposing (Quantity)
import Svg
import Svg.Attributes
import Theme



-- MODEL


type Field
    = X
    | O
    | Empty


type alias TicTacToe =
    { field_1 : Field
    , field_2 : Field
    , field_3 : Field
    , field_4 : Field
    , field_5 : Field
    , field_6 : Field
    , field_7 : Field
    , field_8 : Field
    , field_9 : Field
    }


decoder : D.Decoder TicTacToe
decoder =
    D.map3
        (\( a, b, c ) ( d, e, f ) ( g, h, i ) ->
            TicTacToe a b c d e f g h i
        )
        (D.map3 (\a b c -> ( a, b, c )) fieldDecoder fieldDecoder fieldDecoder)
        (D.map3 (\a b c -> ( a, b, c )) fieldDecoder fieldDecoder fieldDecoder)
        (D.map3 (\a b c -> ( a, b, c )) fieldDecoder fieldDecoder fieldDecoder)


empty : TicTacToe
empty =
    { field_1 = Empty
    , field_2 = Empty
    , field_3 = Empty
    , field_4 = Empty
    , field_5 = Empty
    , field_6 = Empty
    , field_7 = Empty
    , field_8 = Empty
    , field_9 = Empty
    }


fieldDecoder : D.Decoder Field
fieldDecoder =
    D.andThen
        (\s ->
            case s of
                "X" ->
                    D.succeed X

                "O" ->
                    D.succeed O

                "" ->
                    D.succeed Empty

                _ ->
                    D.fail "Unknown field type"
        )
        D.string



-- VIEW


view :
    { flavor : Theme.Flavor
    , game : TicTacToe
    , height : Quantity Int Pixels
    , width : Quantity Int Pixels
    }
    -> Element msg
view data =
    Layout.svg
        { aspectRatio = 1 / 1
        , height = Pixels.inPixels data.height
        , width = Pixels.inPixels data.width
        , viewMinX = 0
        , viewMaxX = 300
        , viewMinY = 0
        , viewMaxY = 300
        , svg =
            Svg.g
                [ Svg.Attributes.strokeLinecap "round"
                ]
                [ svgField { field = data.game.field_1, flavor = data.flavor, offsetX = 0, offsetY = 0 }
                , svgField { field = data.game.field_2, flavor = data.flavor, offsetX = 1, offsetY = 0 }
                , svgField { field = data.game.field_3, flavor = data.flavor, offsetX = 2, offsetY = 0 }
                , svgField { field = data.game.field_4, flavor = data.flavor, offsetX = 0, offsetY = 1 }
                , svgField { field = data.game.field_5, flavor = data.flavor, offsetX = 1, offsetY = 1 }
                , svgField { field = data.game.field_6, flavor = data.flavor, offsetX = 2, offsetY = 1 }
                , svgField { field = data.game.field_7, flavor = data.flavor, offsetX = 0, offsetY = 2 }
                , svgField { field = data.game.field_8, flavor = data.flavor, offsetX = 1, offsetY = 2 }
                , svgField { field = data.game.field_9, flavor = data.flavor, offsetX = 2, offsetY = 2 }
                , Svg.g
                    [ Svg.Attributes.fill <| Color.toCssString <| Theme.text data.flavor
                    , Svg.Attributes.strokeWidth "7.5"
                    ]
                    [ Svg.line
                        [ Svg.Attributes.x1 "100"
                        , Svg.Attributes.x1 "100"
                        , Svg.Attributes.y1 "20"
                        , Svg.Attributes.y2 "280"
                        ]
                        []
                    , Svg.line
                        [ Svg.Attributes.x1 "200"
                        , Svg.Attributes.x1 "200"
                        , Svg.Attributes.y1 "20"
                        , Svg.Attributes.y2 "280"
                        ]
                        []
                    , Svg.line
                        [ Svg.Attributes.x1 "20"
                        , Svg.Attributes.x1 "280"
                        , Svg.Attributes.y1 "100"
                        , Svg.Attributes.y2 "100"
                        ]
                        []
                    , Svg.line
                        [ Svg.Attributes.x1 "20"
                        , Svg.Attributes.x1 "280"
                        , Svg.Attributes.y1 "200"
                        , Svg.Attributes.y2 "200"
                        ]
                        []
                    ]
                ]
        }


svgField :
    { field : Field
    , flavor : Theme.Flavor
    , offsetX : Int
    , offsetY : Int
    }
    -> Svg.Svg svg
svgField data =
    let
        radius =
            35
    in
    Svg.g
        [ Svg.Attributes.fill <| Color.toCssString <| Theme.subtext0 data.flavor
        , Svg.Attributes.strokeWidth "10"
        ]
        [ case data.field of
            Empty ->
                Svg.g [] []

            O ->
                Svg.circle
                    [ Svg.Attributes.cx (String.fromInt (50 + 100 * data.offsetX))
                    , Svg.Attributes.cy (String.fromInt (50 + 100 * data.offsetY))
                    , Svg.Attributes.r (String.fromInt radius)
                    ]
                    []

            X ->
                Svg.g
                    []
                    [ Svg.line
                        [ Svg.Attributes.x1 (String.fromInt (50 - radius))
                        , Svg.Attributes.x2 (String.fromInt (50 + radius))
                        , Svg.Attributes.y1 (String.fromInt (50 - radius))
                        , Svg.Attributes.y2 (String.fromInt (50 + radius))
                        ]
                        []
                    , Svg.line
                        [ Svg.Attributes.x1 (String.fromInt (50 - radius))
                        , Svg.Attributes.x2 (String.fromInt (50 + radius))
                        , Svg.Attributes.y1 (String.fromInt (50 + radius))
                        , Svg.Attributes.y2 (String.fromInt (50 - radius))
                        ]
                        []
                    ]
        ]