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


signal chart_plotted(chart)
signal point_pressed(point)


const OFFSET: Vector2 = Vector2(0,0)


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 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 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

var templates: Dictionary = {}


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