"""Look at what's at the divergence boundary."""
from __future__ import annotations
import sys
from pathlib import Path

REPO = Path(__file__).resolve().parents[1]
sys.path.insert(0, str(REPO))

from minimateplus.waveform_codec import walk_body, find_data_start, parse_segment_header
from analysis_idf.recon import TARGET, TXT, load_sidecar_samples


def main():
    buf = TARGET.read_bytes()
    body = buf[0x0f1f:]
    start = find_data_start(body)
    print(f"data_start: {start}  (= file offset 0x{0x0f1f + start:04x})")

    blocks = walk_body(body, start)
    print(f"{len(blocks)} blocks total")
    print()

    # First 25 blocks
    print("=== first 30 blocks ===")
    for i, b in enumerate(blocks[:30]):
        body_off = 0x0f1f + b.offset
        if b.tag_hi == 0x40:
            hdr = parse_segment_header(b)
            print(f"  [{i:3d}] @0x{body_off:04x}  {b.kind}  (segment header)  counter={hdr['counter'] if hdr else '?'}  field2={hdr['field2'].hex() if hdr else '?'}  anchor={hdr['anchor_bytes'].hex() if hdr else '?'}  tail={hdr['tail'].hex() if hdr else '?'}")
        else:
            print(f"  [{i:3d}] @0x{body_off:04x}  {b.kind}  len={b.length}  data={b.data[:16].hex()}")
    print()

    # Cumulative sample counts per block to find which block contains sample 254
    print("=== cumulative samples through blocks ===")
    cur_ch = "Tran"
    rotation = ["Vert", "Long", "MicL", "Tran"]
    seg_count = 0
    samples_in_curseg = 2  # preamble Tran[0], Tran[1]
    for i, b in enumerate(blocks[:30]):
        if b.tag_hi == 0x40:
            seg_count += 1
            prev_ch = cur_ch
            cur_ch = rotation[(seg_count - 1) % 4]
            print(f"  [{i:3d}] 40 02 -> end of {prev_ch} segment, start {cur_ch} (segment {seg_count})")
            samples_in_curseg = 2  # anchors
        elif (b.tag_hi & 0xF0) == 0x10:
            nn = ((b.tag_hi & 0x0F) << 8) | b.tag_lo
            samples_in_curseg += nn
            print(f"  [{i:3d}] {b.kind} nibble: +{nn} samples, ch={cur_ch}, ch_total~{samples_in_curseg}")
        elif (b.tag_hi & 0xF0) == 0x20:
            nn = ((b.tag_hi & 0x0F) << 8) | b.tag_lo
            samples_in_curseg += nn
            print(f"  [{i:3d}] {b.kind} int8: +{nn} samples, ch={cur_ch}, ch_total~{samples_in_curseg}")
        elif b.tag_hi == 0x00:
            samples_in_curseg += b.tag_lo
            print(f"  [{i:3d}] {b.kind} RLE: +{b.tag_lo}, ch={cur_ch}, ch_total~{samples_in_curseg}")
        elif b.tag_hi == 0x30:
            samples_in_curseg += b.tag_lo
            print(f"  [{i:3d}] {b.kind} packed12: +{b.tag_lo} samples, ch={cur_ch}, ch_total~{samples_in_curseg}")


if __name__ == "__main__":
    main()