#!/usr/bin/env bash
# Builds wire-episode17/ and drives a real push/clone against the local
# MuseHub hub for Episode 17 ("The Wire Protocol"). Requires the local
# MuseHub dev stack running. Re-run to regenerate; never hand-edit the
# repo directory directly.
set -euo pipefail

HERE="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
REPO="$HERE/wire-episode17"
CLONE_DIR="$HERE/wire-episode17-clone"

rm -rf "$REPO" "$CLONE_DIR"
mkdir -p "$REPO"
cd "$REPO"

muse init --json | python3 -m json.tool
echo "hello wire protocol" > README.md
muse code add .
muse commit -m "Initial commit for wire protocol demo" \
  --agent-id claude-code --model-id claude-sonnet-5 --sign

echo
echo "=== Part 1: build a real wire mpack, parse it by hand ==="
COMMIT=$(muse rev-parse HEAD --json | python3 -c "import json,sys; print(json.load(sys.stdin)['commit_id'])")
python3 - "$COMMIT" <<'PY'
import sys, struct, hashlib, pathlib
sys.path.insert(0, str(pathlib.Path.home() / "ecosystem" / "muse"))
from muse.core.mpack import build_mpack, build_wire_mpack

commit_id = sys.argv[1]
root = pathlib.Path(".")
mpack = build_mpack(root, [commit_id], have=set())
wire = build_wire_mpack(mpack, meta={"repo_id": "demo", "branch": "main", "head_commit_id": commit_id})
pathlib.Path("wire.mpack").write_bytes(wire)

print("total wire size:", len(wire), "bytes")
print("header (hex):", wire[:6].hex(' '))
version, section_count = struct.unpack_from("<BB", wire, 4)
print(f"magic={wire[:4]!r} version={version} section_count={section_count}")

names = {1: "BLOBS", 2: "COMMITS", 3: "SNAPSHOTS", 4: "TAGS", 5: "META"}
cursor = 6
for i in range(section_count):
    sec_type = wire[cursor]
    sec_offset, sec_length = struct.unpack_from("<QQ", wire, cursor + 1)
    print(f"  [{i}] type={sec_type} ({names.get(sec_type)}) offset={sec_offset} length={sec_length}")
    cursor += 17

footer = wire[-32:]
computed = hashlib.sha256(wire[:-32]).digest()
print("footer match:", footer == computed)
PY

echo
echo "=== Part 2: tamper with one byte, confirm the footer catches it ==="
python3 - <<'PY'
import sys, pathlib
sys.path.insert(0, str(pathlib.Path.home() / "ecosystem" / "muse"))
from muse.core.mpack import parse_wire_mpack

data = bytearray(pathlib.Path("wire.mpack").read_bytes())
data[200] ^= 0xFF
try:
    parse_wire_mpack(bytes(data))
    print("NO ERROR RAISED -- would be a bug")
except Exception as e:
    print(f"Correctly rejected: {type(e).__name__}: {e}")
PY
rm -f wire.mpack

echo
echo "=== Part 3: a real push over the wire (verbose transcript) ==="
muse -C ~/ecosystem/musehub hub repo delete gabriel/wire-episode17 --yes --json > /dev/null 2>&1 || true
muse -C ~/ecosystem/musehub hub repo create --name wire-episode17 --visibility public --json | python3 -m json.tool | head -6
muse remote add local https://localhost:1337/gabriel/wire-episode17 --json > /dev/null 2>&1 || \
  muse remote set-url local https://localhost:1337/gabriel/wire-episode17 --json > /dev/null
muse push local main --force --json

echo
echo "=== Part 4: a second, incremental commit -- only new blobs travel ==="
echo "second line" >> README.md
muse code add README.md
muse commit -m "Second commit, shares two objects with the first" \
  --agent-id claude-code --model-id claude-sonnet-5 --sign
muse push local main --json

echo
echo "=== Part 5: clone -- the asymmetric, simpler fetch path ==="
mkdir -p "$CLONE_DIR"
cd "$CLONE_DIR"
muse clone https://localhost:1337/gabriel/wire-episode17 --json | tail -20

echo
echo "Demo built at $REPO and $CLONE_DIR"