tool
extends Chart2D

"""
[Linechart2D] - General purpose node for Line Charts
A line chart or line plot or line graph or curve chart is a type of chart which
displays information as a series of data points called 'markers'
connected by straight line segments.
It is a basic type of chart common in many fields. It is similar to a scatter plot
except that the measurement points are ordered (typically by their x-axis value)
and joined with straight line segments.
A line chart is often used to visualize a trend in data over intervals of time –
a time series – thus the line is often drawn chronologically.
In these cases they are known as run charts.
/ source: Wikipedia /
"""


var OutlinesTween: Tween
var FunctionsTween: Tween
var Functions: Node2D
var GridTween: Tween
var PointData: PointData
var Outlines: Line2D
var Grid: Node2D

var point_node: PackedScene = preload("../Utilities/Point/Point.tscn")
var FunctionLegend: PackedScene = preload("../Utilities/Legend/FunctionLegend.tscn")

var font_size: float = 16
var const_height: float = font_size / 2 * font_size / 20
var const_width: float = font_size / 2

var OFFSET: Vector2 = Vector2(0,0)

#-------------------------------------------------------------------------#
var origin: Vector2

# actual distance between x and y values
var x_pass: float
var y_pass: float

# vertical distance between y consecutive points used for intervals
var v_dist: float
var h_dist: float

# quantization, representing the interval in which values will be displayed

# define values on x an y axis
var x_chors: Array
var y_chors: Array

# actual coordinates of points (in pixel)
var x_coordinates: Array
var y_coordinates: Array

# datas contained in file
var datas: Array

# amount of functions to represent
var functions: int = 0

var x_label: String

# database values
var x_datas: Array
var y_datas: Array

# labels displayed on chart
var x_labels: Array
var y_labels: Array

var x_margin_min: int = 0
var y_margin_min: int = 0

# actual values of point, from the database
var point_values: Array

# actual position of points in pixel
var point_positions: Array

var legend: Array setget set_legend,get_legend

# ---------------------
export (Vector2) var SIZE: Vector2 = Vector2() setget _set_size
export (String, FILE, "*.txt, *.csv") var source: String = ""
export (String) var delimiter: String = ";"
export (bool) var origin_at_zero: bool = true

export (bool) var are_values_columns: bool = false
export (int, 0, 100) var x_values_index: int = 0
export(bool) var show_x_values_as_labels: bool = true

#export (float,1,20,0.5) var column_width: float = 10
#export (float,0,10,0.5) var column_gap: float = 2

export (float, 0.1, 10.0) var x_decim: float = 5.0
export (float, 0.1, 10.0) var y_decim: float = 5.0
export (PointShapes) var point_shape: int = 0
export (PoolColorArray) var function_colors = [Color("#1e1e1e")]
export (Color) var v_lines_color: Color = Color("#cacaca")
export (Color) var h_lines_color: Color = Color("#cacaca")

export (bool) var boxed: bool = true
export (Color) var box_color: Color = Color("#1e1e1e")
export (Font) var font: Font
export (Font) var bold_font: Font
export (Color) var font_color: Color = Color("#1e1e1e")
export (TemplatesNames) var template: int = Chart.TemplatesNames.Default setget apply_template
export (float, 0.1, 1) var drawing_duration: float = 0.5
export (bool) var invert_chart: bool = false

var templates: Dictionary = {}

signal chart_plotted(chart)
signal point_pressed(point)


func _point_plotted():
    pass


func _ready():
    _get_children()


func _get_children():
    OutlinesTween = $OutlinesTween
    FunctionsTween = $FunctionsTween
    Functions = $Functions
    GridTween = $GridTween
    PointData = $PointData/PointData
    Outlines = $Outlines
    Grid = $Grid


func _set_size(size: Vector2):
    SIZE = size
    build_chart()
    if Engine.editor_hint:
        _get_children()
        Outlines.set_point_position(0, Vector2(origin.x, 0))
        Outlines.set_point_position(1, Vector2(SIZE.x, 0))
        Outlines.set_point_position(2, Vector2(SIZE.x, origin.y))
        Outlines.set_point_position(3, origin)
        Outlines.set_point_position(4, Vector2(origin.x, 0))

        Grid.get_node("VLine").set_point_position(0, Vector2((OFFSET.x + SIZE.x) / 2,0))
        Grid.get_node("VLine").set_point_position(1, Vector2((OFFSET.x + SIZE.x) / 2, origin.y))
        Grid.get_node("HLine").set_point_position(0, Vector2(origin.x, origin.y / 2))
        Grid.get_node("HLine").set_point_position(1, Vector2(SIZE.x, origin.y / 2))


func clear():
    Outlines.points = []
    Grid.get_node("HLine").queue_free()
    Grid.get_node("VLine").queue_free()


func load_font():
    if font != null:
        font_size = font.get_height()
        var theme: Theme = Theme.new()
        theme.set_default_font(font)
        PointData.set_theme(theme)
    else:
        var lbl = Label.new()
        font = lbl.get_font("")
        lbl.free()
    if bold_font != null:
        PointData.Data.set("custom_fonts/font",bold_font)


func _plot(source: String, delimiter: String, are_values_columns: bool, x_values_index: int):
    randomize()

    clear()

    load_font()
    PointData.hide()

    datas = read_datas(source, delimiter)
    count_functions()
    structure_datas(datas, are_values_columns, x_values_index)
    build_chart()
    calculate_pass()
    calculate_coordinates()
    calculate_colors()
    draw_chart()

    create_legend()
    emit_signal("chart_plotted", self)


func plot():
    randomize()

    clear()

    load_font()
    PointData.hide()

    if source == "" or source == null:
        Utilities._print_message("Can't plot a chart without a Source file. Please, choose it in editor, or use the custom function _plot().", 1)
        return
    datas = read_datas(source,delimiter)
    count_functions()
    structure_datas(datas, are_values_columns, x_values_index)
    build_chart()
    calculate_pass()
    calculate_coordinates()
    calculate_colors()
    draw_chart()

    create_legend()
    emit_signal("chart_plotted", self)


func calculate_colors():
    if function_colors.empty() or function_colors.size() < functions:
        for function in functions:
            function_colors.append(Color("#1e1e1e"))


func draw_chart():
    draw_outlines()
    draw_v_grid()
    draw_h_grid()
    draw_functions()


func draw_outlines():
    if boxed:
        Outlines.set_default_color(box_color)
        OutlinesTween.interpolate_method(
                Outlines,
                "add_point",
                Vector2(origin.x, 0),
                Vector2(SIZE.x, 0),
                drawing_duration * 0.5,
                Tween.TRANS_QUINT,
                Tween.EASE_OUT)
        OutlinesTween.start()
        yield(OutlinesTween, "tween_all_completed")
        OutlinesTween.interpolate_method(
                Outlines,
                "add_point",
                Vector2(SIZE.x,0),
                Vector2(SIZE.x, origin.y),
                drawing_duration * 0.5,
                Tween.TRANS_QUINT,
                Tween.EASE_OUT)
        OutlinesTween.start()
        yield(OutlinesTween,"tween_all_completed")

    OutlinesTween.interpolate_method(
            Outlines,
            "add_point",
            Vector2(SIZE.x,origin.y),
            origin,
            drawing_duration * 0.5,
            Tween.TRANS_QUINT,
            Tween.EASE_OUT)
    OutlinesTween.start()
    yield(OutlinesTween, "tween_all_completed")
    OutlinesTween.interpolate_method(
            Outlines,
            "add_point",
            origin,
            Vector2(origin.x, 0),
            drawing_duration * 0.5,
            Tween.TRANS_QUINT,
            Tween.EASE_OUT)
    OutlinesTween.start()
    yield(OutlinesTween, "tween_all_completed")


func draw_v_grid():
    for p in x_chors.size():
        var point: Vector2 = origin + Vector2((p) * x_pass, 0)
        var v_grid: Line2D = Line2D.new()
        Grid.add_child(v_grid)
        v_grid.set_width(1)
        v_grid.set_default_color(v_lines_color)
        add_label(point + Vector2(-const_width / 2 * x_chors[p].length(), font_size / 2), x_chors[p])
        GridTween.interpolate_method(
                v_grid,
                "add_point",
                point,
                point - Vector2(0, SIZE.y - OFFSET.y),
                drawing_duration / (x_chors.size()),
                Tween.TRANS_EXPO,
                Tween.EASE_OUT)
        GridTween.start()
        yield(GridTween,"tween_all_completed")


func draw_h_grid():
    for p in y_chors.size():
        var point: Vector2 = origin - Vector2(0, p * y_pass)
        var h_grid: Line2D = Line2D.new()
        Grid.add_child(h_grid)
        h_grid.set_width(1)
        h_grid.set_default_color(h_lines_color)
        add_label(point-Vector2(y_chors[p].length() * const_width + font_size, font_size / 2), y_chors[p])
        GridTween.interpolate_method(
                h_grid,
                "add_point",
                point,
                Vector2(SIZE.x,point.y),
                drawing_duration / (y_chors.size()),
                Tween.TRANS_EXPO,
                Tween.EASE_OUT)
        GridTween.start()
        yield(GridTween,"tween_all_completed")


func add_label(point: Vector2, text: String):
        var lbl: Label = Label.new()
        if font != null:
            lbl.set("custom_fonts/font", font)
        lbl.set("custom_colors/font_color", font_color)
        Grid.add_child(lbl)
        lbl.rect_position = point
        lbl.set_text(text)


func draw_functions():
    for function in point_positions.size():
        draw_function(function, point_positions[function])


func draw_function(f_index: int, function: Array):
    var line: Line2D = Line2D.new()
    var backline: Line2D = Line2D.new()
    construct_line(line, backline, f_index, function)
    var pointv: Point
    for point in function.size():
        pointv = point_node.instance()
        Functions.add_child(pointv)
        pointv.connect("_mouse_entered", self, "show_data")
        pointv.connect("_mouse_exited", self, "hide_data")
        pointv.connect("_point_pressed", self, "point_pressed")
        pointv.create_point(
                point_shape,
                function_colors[f_index],
                Color.white, function[point],
                pointv.format_value(point_values[f_index][point], false, false),
                y_labels[point if invert_chart else f_index] as String)
        if point < function.size() - 1:
            FunctionsTween.interpolate_method(
                    line,
                    "add_point",
                    function[point],
                    function[point + 1],
                    drawing_duration / function.size(),
                    Tween.TRANS_QUINT,
                    Tween.EASE_OUT)
            FunctionsTween.start()
            yield(FunctionsTween, "tween_all_completed")


func construct_line(line: Line2D, backline: Line2D, f_index: int, function: Array):
    var midtone = Color(
            Color(function_colors[f_index]).r,
            Color(function_colors[f_index]).g,
            Color(function_colors[f_index]).b,
            Color(function_colors[f_index]).a / 2)
    backline.set_width(3)
    backline.set_default_color(midtone)
    backline.antialiased = true
    Functions.add_child(backline)
    line.set_width(2)
    line.set_default_color(function_colors[f_index])
    line.antialiased = true
    Functions.add_child(line)


func read_datas(source: String, delimiter: String):
    var file: File = File.new()
    file.open(source, File.READ)
    var content: Array
    while not file.eof_reached():
        var line: PoolStringArray = file.get_csv_line(delimiter)
        content.append(line)
    file.close()
    for data in content:
        if data.size() < 2:
            content.erase(data)
    return content


func structure_datas(database: Array, are_values_columns: bool, x_values_index: int):
    # @x_values_index can be either a column or a row relative to x values
    # @y_values can be either a column or a row relative to y values
    self.are_values_columns = are_values_columns
    match are_values_columns:
        true:
            for row in database.size():
                var t_vals: Array
                for column in database[row].size():
                    if column == x_values_index:
                        var x_data = database[row][column]
                        if x_data.is_valid_float() or x_data.is_valid_integer():
                            x_datas.append(x_data as float)
                        else:
                            x_datas.append(x_data.replace(",", ".") as float)
                    else:
                        if row != 0:
                            var y_data = database[row][column]
                            if y_data.is_valid_float() or y_data.is_valid_integer():
                                t_vals.append(y_data as float)
                            else:
                                t_vals.append(y_data.replace(",", ".") as float)
                        else:
                            y_labels.append(str(database[row][column]))
                if not t_vals.empty():
                    y_datas.append(t_vals)
            x_label = str(x_datas.pop_front())
        false:
            for row in database.size():
                if row == x_values_index:
                    x_datas = (database[row])
                    x_label = x_datas.pop_front() as String
                else:
                    var values = database[row] as Array
                    y_labels.append(values.pop_front() as String)
                    y_datas.append(values)
            for data in y_datas:
                for value in data.size():
                    data[value] = data[value] as float

    # draw y labels
    var to_order: Array
    var to_order_min: Array
    for cluster in y_datas.size():
        # define x_chors and y_chors
        var ordered_cluster = y_datas[cluster] as Array
        ordered_cluster.sort()
        ordered_cluster = PoolIntArray(ordered_cluster)
        var margin_max = ordered_cluster[ordered_cluster.size() - 1]
        var margin_min = ordered_cluster[0]
        to_order.append(margin_max)
        to_order_min.append(margin_min)

    to_order.sort()
    to_order_min.sort()
    var margin = to_order.pop_back()
    if not origin_at_zero:
        y_margin_min = to_order_min.pop_front()
    v_dist = y_decim * pow(10.0,str(margin).length() - 2)
    var multi = 0
    var p = (v_dist * multi) + (y_margin_min if not origin_at_zero else 0)
    y_chors.append(p as String)
    while p < margin:
        multi+=1
        p = (v_dist * multi) + (y_margin_min if not origin_at_zero else 0)
        y_chors.append(p as String)

    # draw x_labels
    if not show_x_values_as_labels:
        to_order.clear()
        to_order = x_datas as PoolIntArray

        to_order.sort()
        margin = to_order.pop_back()
        if not origin_at_zero:
            x_margin_min = to_order.pop_front()
        h_dist = x_decim * pow(10.0, str(margin).length() - 2)
        multi = 0
        p = (h_dist * multi) + (x_margin_min if not origin_at_zero else 0)
        x_labels.append(p as String)
        while p < margin:
            multi += 1
            p = (h_dist * multi) + (x_margin_min if not origin_at_zero else 0)
            x_labels.append(p as String)


func build_chart():
    origin = Vector2(OFFSET.x, SIZE.y - OFFSET.y)


func calculate_pass():
    if invert_chart:
        x_chors = y_labels as PoolStringArray
    else:
        if show_x_values_as_labels:
            x_chors = x_datas as PoolStringArray
        else:
            x_chors = x_labels

    # calculate distance in pixel between 2 consecutive values/datas
    x_pass = (SIZE.x - OFFSET.x) / (x_chors.size() - 1)
    y_pass = origin.y / (y_chors.size() - 1)


func calculate_coordinates():
    x_coordinates.clear()
    y_coordinates.clear()
    point_values.clear()
    point_positions.clear()

    if invert_chart:
        for column in y_datas[0].size():
            var single_coordinates: Array
            for row in y_datas:
                if origin_at_zero:
                    single_coordinates.append((row[column] * y_pass) / v_dist)
                else:
                    single_coordinates.append((row[column] - y_margin_min) * y_pass / v_dist)
            y_coordinates.append(single_coordinates)
    else:
        for cluster in y_datas:
            var single_coordinates: Array
            for value in cluster.size():
                if origin_at_zero:
                    single_coordinates.append((cluster[value] * y_pass) / v_dist)
                else:
                    single_coordinates.append((cluster[value] - y_margin_min) * y_pass / v_dist)
            y_coordinates.append(single_coordinates)

    if show_x_values_as_labels:
        for x in x_datas.size():
            x_coordinates.append(x_pass * x)
    else:
        for x in x_datas.size():
            if origin_at_zero:
                if invert_chart:
                    x_coordinates.append(x_pass * x)
                else:
                    x_coordinates.append(x_datas[x] * x_pass / h_dist)
            else:
                x_coordinates.append((x_datas[x] - x_margin_min) * x_pass / h_dist)

    for f in functions:
        point_values.append([])
        point_positions.append([])

    if invert_chart:
        for function in y_coordinates.size():
            for function_value in y_coordinates[function].size():
                if are_values_columns:
                    point_positions[function_value].append(Vector2(
                            x_coordinates[function] + origin.x,
                            origin.y - y_coordinates[function][function_value]))
                    point_values[function_value].append(
                            [x_datas[function_value], y_datas[function_value][function]])
                else:
                    point_positions[function].append(Vector2(
                            x_coordinates[function_value] + origin.x,
                            origin.y - y_coordinates[function][function_value]))
                    point_values[function].append(
                        [x_datas[function_value], y_datas[function_value][function]])
    else:
        for cluster in y_coordinates.size():
            for y in y_coordinates[cluster].size():
                if are_values_columns:
                    point_values[y].append([x_datas[cluster],y_datas[cluster][y]])
                    point_positions[y].append(Vector2(
                        x_coordinates[cluster] + origin.x,
                        origin.y - y_coordinates[cluster][y]))
                else:
                    point_values[cluster].append([x_datas[y],y_datas[cluster][y]])
                    point_positions[cluster].append(Vector2(
                        x_coordinates[y] + origin.x,
                        origin.y - y_coordinates[cluster][y]))


func redraw():
    build_chart()
    calculate_pass()
    calculate_coordinates()
    update()


func show_data(point):
    PointData.update_datas(point)
    PointData.show()


func hide_data():
    PointData.hide()


func clear_points():
    function_colors.clear()
    if Functions.get_children():
        for function in Functions.get_children():
            function.queue_free()


func set_legend(l: Array):
    legend = l


func get_legend():
    return legend


func invert_chart():
    invert_chart = !invert_chart
    count_functions()
    redraw()
    create_legend()


func count_functions():
    if are_values_columns:
        if not invert_chart:
            functions = datas[0].size() - 1
        else:
            functions = datas.size() - 1
    else:
        if invert_chart:
            functions = datas[0].size() - 1
        else:
            functions = datas.size() - 1


func create_legend():
    legend.clear()
    for function in functions:
        var function_legend = FunctionLegend.instance()
        var f_name: String
        if invert_chart:
            f_name = x_datas[function] as String
        else:
            f_name = y_labels[function]
        var legend_font: Font
        if font != null:
            legend_font = font
        if bold_font != null:
            legend_font = bold_font
        function_legend.create_legend(f_name, function_colors[function], bold_font, font_color)
        legend.append(function_legend)


func apply_template(template_name: int):
    template = template_name
    templates = Utilities._load_templates()
    if template_name != null:
        var custom_template = templates.get(templates.keys()[template_name])
        function_colors = custom_template.function_colors as PoolColorArray
        v_lines_color = Color(custom_template.v_lines_color)
        h_lines_color = Color(custom_template.h_lines_color)
        box_color = Color(custom_template.outline_color)
        font_color = Color(custom_template.font_color)
    property_list_changed_notify()

    if Engine.editor_hint:
        _get_children()
        Outlines.set_default_color(box_color)
        Grid.get_node("VLine").set_default_color(v_lines_color)
        Grid.get_node("HLine").set_default_color(h_lines_color)


func _enter_tree():
    _ready()


# Signal Repeaters
func point_pressed(point: Point) -> Point:
    return point