# target_simulator/gui/ppi_display.py

"""
A Tkinter widget that displays a Plan Position Indicator (PPI) using Matplotlib.
"""

import tkinter as tk
from tkinter import ttk
import math
import numpy as np
from matplotlib.figure import Figure
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg

from core.models import Target
from typing import List


class PPIDisplay(ttk.Frame):
    """A custom widget for the PPI radar display."""

    def __init__(self, master, max_range_nm: int = 100, scan_limit_deg: int = 60):
        super().__init__(master)
        self.max_range = max_range_nm
        self.scan_limit_deg = scan_limit_deg
        
        self._create_controls()
        self._create_plot()
        
    def _create_controls(self):
        """Creates the control widgets for the PPI display."""
        controls_frame = ttk.Frame(self)
        controls_frame.pack(side=tk.TOP, fill=tk.X, padx=5, pady=5)

        ttk.Label(controls_frame, text="Range (NM):").pack(side=tk.LEFT)

        # Generate range steps
        steps = list(range(self.max_range, 19, -20))
        if 10 not in steps:
            steps.append(10)

        self.range_var = tk.IntVar(value=self.max_range)
        self.range_selector = ttk.Combobox(
            controls_frame, 
            textvariable=self.range_var, 
            values=steps, 
            state="readonly",
            width=5
        )
        self.range_selector.pack(side=tk.LEFT)
        self.range_selector.bind("<<ComboboxSelected>>", self._on_range_selected)

    def _create_plot(self):
        """Initializes the Matplotlib polar plot."""
        # Dark theme for the plot
        fig = Figure(figsize=(5, 5), dpi=100, facecolor='#3E3E3E')
        fig.subplots_adjust(left=0.05, right=0.95, top=0.85, bottom=0.05)
        
        self.ax = fig.add_subplot(111, projection='polar', facecolor='#2E2E2E')
        
        # Configure polar axes
        self.ax.set_theta_zero_location('N')  # 0 degrees at the top
        self.ax.set_theta_direction(-1)       # Clockwise rotation
        self.ax.set_rlabel_position(90)
        self.ax.set_ylim(0, self.max_range)
        
        # Style the plot
        self.ax.tick_params(axis='x', colors='white')
        self.ax.tick_params(axis='y', colors='white')
        self.ax.grid(color='white', linestyle='--', linewidth=0.5, alpha=0.5)
        self.ax.spines['polar'].set_color('white')

        self.ax.set_title("PPI Display", color='white', y=1.08)
        
        # Draw scan sector limits
        limit_rad = np.deg2rad(self.scan_limit_deg)
        self.ax.plot([limit_rad, limit_rad], [0, self.max_range], color='yellow', linestyle='--', linewidth=1)
        self.ax.plot([-limit_rad, -limit_rad], [0, self.max_range], color='yellow', linestyle='--', linewidth=1)

        # Initial plot for targets (an empty plot to be updated later)
        self.target_plot, = self.ax.plot([], [], 'ro', markersize=6) # 'ro' = red circle

        # Embed the plot in a Tkinter canvas
        self.canvas = FigureCanvasTkAgg(fig, master=self)
        self.canvas.draw()
        self.canvas.get_tk_widget().pack(side=tk.TOP, fill=tk.BOTH, expand=True)

    def _on_range_selected(self, event):
        """Handles the selection of a new range from the combobox."""
        new_range = self.range_var.get()
        self.ax.set_ylim(0, new_range)
        self.canvas.draw()

    def update_targets(self, targets: List[Target]):
        """
        Updates the positions of targets on the PPI display.

        Args:
            targets: A list of Target objects to display.
        """
        active_targets = [t for t in targets if t.active]
        
        if not active_targets:
            self.target_plot.set_data([], [])
        else:
            # Matplotlib polar plot needs angles in radians
            theta = [math.radians(t.azimuth_deg) for t in active_targets]
            r = [t.range_nm for t in active_targets]
            self.target_plot.set_data(theta, r)

        # Redraw the canvas to show the changes
        self.canvas.draw()