"""A fake opencode 2.x CLI for tests (Issue #60): only what MAM calls.

- `debug paths` prints the `data` and `db` lines of the real command (the db
  follows XDG_DATA_HOME, else HOME/.local/share; the database is not created);
- `session delete [--standalone] [--] <id>` deletes the session and its child
  sessions from the 2.x tables (session_v2, session_message, session_inbox,
  session_pending, event, event_sequence) and leaves the tables a 1.x
  migration keeps (session, message, part, todo, session_share), as the real
  2.0.32 command was measured to do; prints `Session <id> deleted`, or
  `Session not found: <id>` with exit 1.

Tests never run a real opencode: a real one would migrate the test's
database. The contract against a real binary is checked by the opt-in test in
tests/test_issue60_opencode_v2.py.
"""
import os
import stat

SCRIPT = r'''#!/usr/bin/env python3
import os, sqlite3, sys
args = sys.argv[1:]
data = os.environ.get("XDG_DATA_HOME") or os.path.join(os.environ.get("HOME", ""), ".local", "share")
db = os.path.join(data, "opencode", "opencode.db")
if args == ["debug", "paths"]:
    print("data       " + os.path.dirname(db))
    print("db         " + db)
    sys.exit(0)
if args[:2] == ["session", "delete"]:
    sid = args[-1]
    conn = sqlite3.connect(db)
    try:
        if not conn.execute("SELECT 1 FROM session_v2 WHERE id=?", (sid,)).fetchone():
            print("Session not found: " + sid, file=sys.stderr)
            sys.exit(1)
        ids, todo = [], [sid]
        while todo:
            cur = todo.pop()
            ids.append(cur)
            todo += [r[0] for r in conn.execute("SELECT id FROM session_v2 WHERE parent_id=?", (cur,))]
        tables = {r[0] for r in conn.execute("SELECT name FROM sqlite_master WHERE type='table'")}
        v2 = (("session_message", "session_id"), ("session_inbox", "session_id"),
              ("session_pending", "session_id"), ("event", "aggregate_id"),
              ("event_sequence", "aggregate_id"), ("session_v2", "id"))
        for t, col in v2:
            if t in tables:
                for i in ids:
                    conn.execute('DELETE FROM "%s" WHERE "%s"=?' % (t, col), (i,))
        conn.commit()
    finally:
        conn.close()
    print("Session " + sid + " deleted")
    sys.exit(0)
sys.exit(0)
'''


def write(path) -> str:
    """Write the fake as an executable `path` and return it as a str."""
    path = str(path)
    os.makedirs(os.path.dirname(path), exist_ok=True)
    with open(path, "w") as f:
        f.write(SCRIPT)
    os.chmod(path, os.stat(path).st_mode | stat.S_IEXEC)
    return path