"""Generate the exact parameter figures; matplotlib is optional for the codec."""
from pathlib import Path
import numpy as np
import matplotlib
matplotlib.use("Agg")
import matplotlib.pyplot as plt
from matplotlib.colors import ListedColormap

ROOT=Path(__file__).resolve().parents[1]
OUT=ROOT/"figures"
OUT.mkdir(exist_ok=True)
plt.rcParams.update({"font.family":"DejaVu Sans","font.size":10,
                    "axes.spines.top":False,"axes.spines.right":False,
                    "axes.labelcolor":"#183242","text.color":"#183242",
                    "axes.edgecolor":"#83939a","savefig.bbox":"tight"})
teal,blue,orange="#167f83","#233e70","#b95f25"

d=np.arange(2,33)
fig,ax=plt.subplots(figsize=(7.4,3.8))
ax.step(d,np.ceil(d/2),where="mid",color=teal,lw=2.4,label="Exact optimum: convolution with a linear relabeling")
ax.plot(d,d+1,color=blue,lw=1.8,ls="--",label="Standard constant scalar rays")
ax.scatter([16],[8],color=orange,s=48,zorder=4)
ax.annotate("GF(256), 65,536 data sites\n24 updates per changed byte",(16,8),xytext=(18,3.0),
            arrowprops={"arrowstyle":"->","color":orange},fontsize=9)
ax.set(xlabel="Dimension d of each data/parity layer",ylabel="Minimum bits per scalar symbol",
       xlim=(1.5,32.5),ylim=(0,35))
ax.set_xticks([2,4,8,12,16,20,24,28,32])
ax.grid(axis="y",alpha=.2)
ax.legend(loc="upper left",frameon=False,fontsize=8.5)
fig.tight_layout()
for ext in ("pdf","png"):fig.savefig(OUT/f"alphabet_law.{ext}",dpi=170)
plt.close(fig)

fig,ax=plt.subplots(figsize=(7.4,3.6))
ax.plot(d,d+1,color=blue,lw=2,label="Absolute support lower bound: d + 1")
ax.step(d,np.ceil(3*d/2),where="mid",color=teal,lw=2,label="Explicit construction at the optimal alphabet")
ax.scatter(np.arange(2,7),np.arange(2,7)+1,s=40,color=orange,zorder=4,
           label="Exact examples attaining both bounds (d = 2 through 6)")
ax.set(xlabel="Dimension d of each layer",ylabel="Parity sites changed by one source update",
       xlim=(1.5,32.5),ylim=(0,52))
ax.grid(axis="y",alpha=.2)
ax.legend(frameon=False,loc="upper left",fontsize=8.3)
fig.tight_layout()
for ext in ("pdf","png"):fig.savefig(OUT/f"update_support.{ext}",dpi=170)
plt.close(fig)

fig,ax=plt.subplots(figsize=(7.4,2.4))
sizes=np.arange(1,11)
general=np.array([int(x>=3) for x in sizes])
commuting=np.array([int(x==3 or x>=5) for x in sizes])
matrix=np.vstack([commuting,general])
ax.imshow(matrix,cmap=ListedColormap(["#f0d9cc","#d5eeeb"]),vmin=0,vmax=1,aspect="auto")
for i in range(2):
    for j in range(10):ax.text(j,i,"YES" if matrix[i,j] else "NO",ha="center",va="center",fontsize=9)
ax.set_xticks(range(10),sizes)
ax.set_yticks([0,1],["Normalized commuting maps","Arbitrary binary matrix maps"])
ax.set_xlabel("Source and parity packet length, in bits")
ax.set_title("GF(4) geometry, three standard rays, equal packet widths",fontsize=11,pad=12)
for spine in ax.spines.values():spine.set_visible(False)
ax.set_xticks(np.arange(-.5,10,1),minor=True)
ax.set_yticks(np.arange(-.5,2,1),minor=True)
ax.grid(which="minor",color="white",lw=3)
ax.tick_params(which="minor",bottom=False,left=False)
fig.tight_layout()
for ext in ("pdf","png"):fig.savefig(OUT/f"noncommuting_gap.{ext}",dpi=170)
plt.close(fig)