import numpy as np
import sys
from decimal import Decimal
from time import time

from ..units import HighPrecisionMatrix

def calculate_distances(positions):
    N = len(positions)
    dists = HighPrecisionMatrix(N,N)
    for i in range(N):
        dists[i][i] = Decimal(0)
        for j in range(i+1, N):
            d = sum([x**2 for x in (positions[i]-positions[j])]).sqrt()
            dists[i][j] = Decimal(d)
            dists[j][i] = Decimal(d)
    return dists

def calculate_distances_np(positions):
    positions = np.array(positions)
    diffs = positions[:, np.newaxis] - positions[np.newaxis, :]
    dists = np.linalg.norm(diffs, axis=-1)
    np.fill_diagonal(dists, 0)
    return dists

def print_progress_bar(iteration, total, start_time, length=50):
    """Prints a progress bar to the console."""
    percent = (iteration / total) * 100
    filled_length = int(length * iteration // total)
    bar = '#' * filled_length + '-' * (length - filled_length)
    sys.stdout.write(f'\r[{bar}] {percent:.2f}% {int(iteration/(time()-start_time))} steps/s')
    sys.stdout.flush()


def format_sig_figs(value, sig_figs):
    """Format a number to a specified number of significant figures for printing."""
    if value == 0:
        return "0"
    return f"{value:.{sig_figs-1}e}"



def plot_points_terminal(vectors, stdscr, scale=500000, grid_width=30, grid_height=30):
    """Plots multiple points in the terminal, scaled and centered at (0,0)."""
    stdscr.clear()

    if not vectors:
        stdscr.addstr(0, 0, "No vectors provided.")
        stdscr.refresh()
        return

    # Apply scaling
    scaled_vectors = {(round(vec[0] / scale), round(vec[1] / scale)) for vec in vectors}

    # Find min and max coordinates
    min_x = min(vec[0] for vec in scaled_vectors)
    max_x = max(vec[0] for vec in scaled_vectors)
    min_y = min(vec[1] for vec in scaled_vectors)
    max_y = max(vec[1] for vec in scaled_vectors)

    # Center offsets to keep (0,0) in middle
    center_x = (grid_width // 2) - min_x
    center_y = (grid_height // 2) - min_y

    # Adjust coordinates for plotting
    adjusted_vectors = {(vec[0] + center_x, vec[1] + center_y) for vec in scaled_vectors}

    # Ensure grid boundaries
    max_terminal_y, max_terminal_x = stdscr.getmaxyx()
    max_x = min(grid_width, max_terminal_x - 5)
    max_y = min(grid_height, max_terminal_y - 5)

    # Draw grid with points
    for i in range(grid_height, -1, -1):
        row = f"{i - center_y:2} | "
        for j in range(grid_width + 1):
            row += "● " if (j, i) in adjusted_vectors else ". "
        stdscr.addstr(max_y - i, 0, row[:max_terminal_x - 1])  # Ensure no overflow

    # Print X-axis labels
    x_labels = "   " + " ".join(f"{j - center_x:2}" for j in range(max_x + 1))
    stdscr.addstr(max_y + 1, 0, x_labels[:max_terminal_x - 1])  # Avoid out-of-bounds error

    stdscr.refresh()