#!/usr/bin/env python3
"""Migrate the 40250 player DB to the 5-page bag (server.patch). Run once, with db/game stopped.

  python3 migrate_db.py [--dry-run] [mysql args...]      (default mysql args: -uroot player)

- Belt-inventory items are stored as window INVENTORY at absolute cells 152..167; they move to 287..302
  (every cell after the bag moves by +135). Worn and dragon-soul-equipped items are stored relative to
  their EQUIPMENT window and do not move.
- player.quickslot / player_deleted.quickslot hold TQuickslot[36] raw: {BYTE type; BYTE pos} (72 bytes)
  becomes {BYTE type; WORD pos} (108 bytes). Item quick slots (type 1) on a belt cell get +135 too.

A row in table mt_migration records the run; a second run changes nothing.
"""
import subprocess
import sys

NAME = "inventory-5-pages"
QUICKSLOT_MAX_NUM = 36
QUICKSLOT_TYPE_ITEM = 1
OLD_BELT = range(152, 168)
SHIFT = 135


def mysql(args, sql):
    out = subprocess.run(["mysql", "-N", "-B"] + args, input=sql, capture_output=True, text=True)
    if out.returncode:
        sys.exit("mysql failed: " + out.stderr.strip())
    return [line.split("\t") for line in out.stdout.splitlines()]


def convert(blob):
    assert len(blob) == QUICKSLOT_MAX_NUM * 2, len(blob)
    out = bytearray()
    for i in range(QUICKSLOT_MAX_NUM):
        kind, pos = blob[2 * i], blob[2 * i + 1]
        if kind == QUICKSLOT_TYPE_ITEM and pos in OLD_BELT:
            pos += SHIFT
        out += bytes([kind, pos & 0xFF, pos >> 8])
    return bytes(out)


def main():
    argv = sys.argv[1:]
    dry = "--dry-run" in argv
    args = [a for a in argv if a != "--dry-run"] or ["-uroot", "player"]

    mysql(args, "CREATE TABLE IF NOT EXISTS mt_migration (name VARCHAR(64) PRIMARY KEY, done DATETIME)")
    if mysql(args, "SELECT name FROM mt_migration WHERE name='%s'" % NAME):
        print("%s: already applied" % NAME)
        return

    sql = ["UPDATE item SET pos = pos + %d WHERE window = 'INVENTORY' AND pos BETWEEN %d AND %d;"
           % (SHIFT, OLD_BELT[0], OLD_BELT[-1])]
    belt = mysql(args, "SELECT COUNT(*) FROM item WHERE window='INVENTORY' AND pos BETWEEN %d AND %d"
                 % (OLD_BELT[0], OLD_BELT[-1]))[0][0]
    bad = mysql(args, "SELECT COUNT(*) FROM item WHERE window='INVENTORY' AND pos BETWEEN 90 AND 151")[0][0]
    if bad != "0":
        sys.exit("%s INVENTORY items at cells 90..151, which 40250 does not use; stop" % bad)
    rows = 0
    for table in ("player", "player_deleted"):
        for pid, blob in mysql(args, "SELECT id, HEX(quickslot) FROM %s" % table):
            data = bytes.fromhex(blob)
            if not data:
                continue
            if len(data) != QUICKSLOT_MAX_NUM * 2:
                sys.exit("%s %s: quickslot is %d bytes, expected %d" % (table, pid, len(data), QUICKSLOT_MAX_NUM * 2))
            sql.append("UPDATE %s SET quickslot = X'%s' WHERE id = %s;" % (table, convert(data).hex().upper(), pid))
            rows += 1
    sql.append("INSERT INTO mt_migration VALUES ('%s', NOW());" % NAME)
    print("%s: %s belt item(s), %d quickslot row(s)" % (NAME, belt, rows))
    if dry:
        print("\n".join(sql))
        return
    mysql(args, "\n".join(sql))
    print("%s: applied" % NAME)


if __name__ == "__main__":
    main()