import matplotlib.pyplot as plt
import matplotlib.colors as mcolors
from matplotlib.patches import Patch
from matplotlib.lines import Line2D
import numpy as np
from scipy.stats import norm
from scipy.interpolate import PchipInterpolator, make_interp_spline

# 1. BBB frequency data
datos_crudos = """Bin Center	% Frequency
0	0.24
0.05	5.14
0.1	3.56
0.15	3.68
0.2	2.91
0.25	2.55
0.3	3.20
0.35	2.47
0.4	2.35
0.45	2.39
0.5	2.63
0.55	2.51
0.6	2.91
0.65	3.11
0.7	2.95
0.75	4.41
0.8	5.18
0.85	5.99
0.9	7.81
0.95	20.31
1	13.71"""

lineas = datos_crudos.strip().split('\n')[1:] 
bins_array = []
freq_array = []
for linea in lineas:
    b, f = linea.strip().split() 
    bins_array.append(float(b))
    freq_array.append(float(f))

x = np.array(bins_array)
y = np.array(freq_array)
bins = x  
freq = y  

# 2. Curve smoothing (Spline)
x_smooth = np.linspace(min(x), max(x), 300)
spl = make_interp_spline(x, y, k=3)
y_smooth = spl(x_smooth)
y_smooth = [val if val > 0 else 0 for val in y_smooth]

# 3. Define colors (BBB Traffic Light)
colors = []
for val in x:
    # High probability of crossing BBB (Green = BBB+)
    if val >= 0.8:
        colors.append('green')
    # Low probability (Red = BBB-)
    elif val <= 0.3:
        colors.append('firebrick')
    # intermediate zone
    else:
        colors.append('gold')

# 4. Create the chart
plt.figure(figsize=(7, 6))

# A. Bars
plt.bar(x, y, width=0.04, color=colors, edgecolor='black', alpha=0.7, label='Data Frequency')

# 5. Tags and Titles
plt.xlabel('Blood-Brain Barrier Permeability Prob. (0=No, 1=Yes)', fontsize=12)
plt.ylabel('% Frequency', fontsize=12)
plt.title('BBB Permeability Distribution', fontsize=14)

# Axle settings
plt.xticks(np.arange(0, 1.1, 0.1))
plt.xlim(-0.05, 1.05)
plt.ylim(0, 22)

# 6. Vertical Legend (To the LEFT so as not to cover the right peak)
legend_elements = [
    Patch(facecolor='green', edgecolor='black', alpha=0.7, label='BBB+ / CNS Active (> 0.8)'),
    Patch(facecolor='gold', edgecolor='black', alpha=0.7, label='Uncertain / Selective (0.3 - 0.8)'),
    Patch(facecolor='firebrick', edgecolor='black', alpha=0.7, label='BBB- / Periphery Only (< 0.3)')
]

plt.legend(handles=legend_elements, loc='upper left', ncol=1, framealpha=0.9)

plt.grid(axis='y', linestyle='--', alpha=0.5)
plt.tight_layout()

plt.show()