"""What does LOSSLESS (palettised-quality) delta coding actually cost at 12fps?

Session 1 measured only a hand-rolled row-span+RLE (3.2:1). The 68000 has ~12x
CPU headroom, so a real LZ decoder is affordable -- byte copies are what the
68000 is good at. This measures the achievable floor at zero extra quality loss.
"""
import sys, zlib, lzma; sys.path.insert(0,'tools/encoder')
import vq, numpy as np
S=sys.argv[1]
RAW=256*192

def rle_delta(a,b,gap=4):
    """session 1's row-span + RLE, reimplemented for comparison"""
    t=0
    for y in range(a.shape[0]):
        d=np.nonzero(a[y]!=b[y])[0]
        if not len(d): continue
        sp=[];s=d[0];p=d[0]
        for x in d[1:]:
            if x-p>gap: sp.append((s,p)); s=x
            p=x
        sp.append((s,p)); t+=2
        for s0,e0 in sp:
            seg=b[y][s0:e0+1]; t+=2; i=0
            while i<len(seg):
                r=1
                while i+r<len(seg) and seg[i+r]==seg[i] and r<127: r+=1
                t += 2 if r>=3 else r; i+=r
    return t

print(f'{"scene":8}{"frames":>7}{"raw KB/s":>9}{"rle":>8}{"xor+zl":>8}{"delta+zl":>9}{"lzma":>8}',flush=True)
tot={}
for s in ['00010','00020','00146','00181']:
    rgb=vq.load_frames(f'{S}/fr_{s}')
    ref,pal=vq.scene_palette(rgb)
    idx=vq.palettise(rgb,ref)
    n=len(idx)-1
    r_rle=sum(rle_delta(idx[i-1],idx[i]) for i in range(1,len(idx)))/n
    # XOR against previous frame then deflate -- unchanged pixels become 0 runs
    r_xor=sum(len(zlib.compress((idx[i]^idx[i-1]).tobytes(),9)) for i in range(1,len(idx)))/n
    # RLE-of-changed-spans payload, then deflate on top
    def spans(a,b,gap=8):
        out=bytearray()
        for y in range(a.shape[0]):
            d=np.nonzero(a[y]!=b[y])[0]
            if not len(d): continue
            sp=[];st=d[0];p=d[0]
            for x in d[1:]:
                if x-p>gap: sp.append((st,p)); st=x
                p=x
            sp.append((st,p))
            for s0,e0 in sp:
                out += bytes([y,s0,e0-s0]) + b[y][s0:e0+1].tobytes()
        return bytes(out)
    r_dz=sum(len(zlib.compress(spans(idx[i-1],idx[i]),9)) for i in range(1,len(idx)))/n
    r_lz=sum(len(lzma.compress(spans(idx[i-1],idx[i]),preset=9))for i in range(1,len(idx)))/n
    f=12/1024.0
    print(f'{s:8}{len(idx):7}{RAW*f:9.0f}{r_rle*f:8.0f}{r_xor*f:8.0f}{r_dz*f:9.0f}{r_lz*f:8.0f}',flush=True)
    for k,v in [('rle',r_rle),('xor',r_xor),('dz',r_dz),('lz',r_lz)]: tot.setdefault(k,[]).append(v)
print()
for k,v in tot.items():
    m=np.mean(v)
    print(f'{k:8} mean {m:7.0f} B/frame  {m*12/1024:6.0f} KB/s  {m*12*22*60/1048576:5.0f} MB/22min  ratio {RAW/m:.1f}:1')