GoogleChart.elm

module GoogleChart exposing (..)

import Html exposing (Html)
import Html.Attributes as HtmlA
import Json.Encode as E
import List.Extra as List
import Chart exposing (..)


colors =
    [ "5DA5DA"
    , "4D4D4D"
    , "FAA43A"
    , "60BD68"
    , "F17CB0"
    , "B2912F"
    , "B276B2"
    , "DECF3F"
    , "F15854"
    ]


view : Chart -> Html msg
view chart =
    let
        ty =
            case chart.plot of
                Pie _ ->
                    "pie"

                Bar _ ->
                    "bar"

                _ ->
                    "line"

        p value =
            E.float value

        -- E.object [("v", E.float value), ("f", E.string <| String.fromFloat value)]
        seriesToData { headerX, headerY, points } =
            E.list (E.list identity) <|
                [ [ E.string headerX, E.string headerY ] ]
                    ++ List.map (\( label, value ) -> [ E.string label, p value ]) points

        data =
            case chart.plot of
                Pie series ->
                    seriesToData series

                Bar series ->
                    seriesToData series

                Line lines ->
                    E.list identity <|
                        [ E.list (E.string << Tuple.first) lines ]
                            ++ (List.map (E.list E.float) <|
                                    List.transpose (List.map Tuple.second lines)
                               )

        hiddenLegend =
            [ ( "legend"
              , E.object
                    [ ( "position", E.string "none" )
                    ]
              )
            ]

        defaultLegend =
            []

        legend =
            case chart.plot of
                Pie _ ->
                    [ ( "legend"
                      , E.object
                            [ ( "position", E.string "right" )
                            , ( "alignment", E.string "center" )
                            , ( "maxLines", E.int 5 )
                            ]
                      )
                    ]

                Bar _ ->
                    hiddenLegend

                _ ->
                    defaultLegend

        defaultArea =
            []

        tenPercentArea =
            [ ( "chartArea"
              , E.object <|
                    [ ( "top", E.string "15%" )
                    , ( "right", E.string "15%" )
                    , ( "bottom", E.string "15%" )
                    , ( "left", E.string "15%" )
                    ]
              )
            ]

        chartArea =
            case chart.plot of
                Pie _ ->
                    tenPercentArea

                Bar _ ->
                    tenPercentArea

                _ ->
                    tenPercentArea

        vAxis =
            case chart.plot of
                Line _ ->
                    [ ( "vAxis"
                      , E.object
                            [ ( "baseline", E.float 2 )
                            ]
                      )
                    ]

                _ ->
                    [ ( "vAxis"
                      , E.object
                            [ ( "format", E.string "percent" )
                            ]
                      )
                    ]

        hAxis =
            case chart.plot of
                Line lines ->
                    [ ( "hAxis"
                      , E.object []
                        -- [ ( "baseline", E.float 1298 )
                        -- ]
                      )
                    ]

                _ ->
                    []
    in
    Html.node
        "google-chart"
        [ HtmlA.property "type" <| E.string ty

        -- , HtmlA.style "width" (chart.size.width |> round |> String.fromInt |> (\x -> x ++ "px"))
        -- , HtmlA.style "height" (chart.size.height |> round |> String.fromInt |> (\x -> x ++ "px"))
        , HtmlA.property "options" <|
            E.object <|
                [ ( "colors", E.list E.string colors )
                , ( "is3D", E.bool True )
                , ( "backgroundColor", E.string "transparent" )

                -- , ( "title", E.string chart.title )
                , ( "titleTextStyle"
                  , E.object <|
                        [ ( "fontSize", E.int 20 )
                        , ( "fontName", E.string "sans-serif" )
                        , ( "bold", E.bool False )
                        ]
                  )

                -- , ( "pieSliceText", E.string "label" )
                ]
                    ++ chartArea
                    ++ legend
                    ++ vAxis
                    ++ hAxis
        , HtmlA.property "data" data
        ]
        []