#!/usr/bin/env python3
"""
Transform repo-style schema JSON into a Hugging Face–friendly "long list":

- Top-level keys like "002125_filename" are moved into each record's INFO:
    INFO.ID = "002125"
    INFO.FILENAME = "filename"
- Normalize tables and columns to consistent lists (not dicts).
- Ensure presence of standard fields with sensible defaults.
- Output as JSON (list) or JSON Lines.

Usage:
    python transform_to_hf.py input.json -o output.json          # JSON array
    python transform_to_hf.py input.json -o output.jsonl --jsonl # JSONL
"""

import argparse
import json
import sys
from typing import Any, Dict, List, Optional
import gzip

# -------- Defaults & helpers --------

DEFAULT_COLUMN = {
    "TYPE": None,
    "NULLABLE": True,
    "UNIQUE": False,
    "DEFAULT": None,
    "CHECKS": [],
    "IS_PRIMARY": False,
    "IS_INDEX": False,
    "VALUES": None,
}

DEFAULT_TABLE = {
    "PRIMARY_KEYS": [],
    "FOREIGN_KEYS": [],
    "CHECKS": [],
    "INDEXES": [],
}

from typing import Tuple, Set
from huggingface_hub import HfApi, HfFolder
from datasets import Dataset

def _normalize_index_like(x) -> List[str]:
    """
    Normalize index-like fields (INDEXES, PRIMARY_KEYS) into a list[str].
    - Single column indexes expressed as ["col"] or [["col"]] -> ["col"]
    - Composite indexes like ["a","b"] or [["a","b"]] -> ["a,b"]
    - Scalars pass through -> ["scalar"]
    """
    if x is None:
        return []
    if not isinstance(x, list):
        x = [x]

    out: List[str] = []
    for item in x:
        if item is None:
            continue
        if isinstance(item, (list, tuple, set)):
            flat = [_strify_scalar(v) for v in item if v is not None]
            if len(flat) == 1:
                out.append(flat[0])
            elif len(flat) > 1:
                out.append(",".join(flat))
        else:
            out.append(_strify_scalar(item))
    return out

def _strify_scalar(x):
    if x is None:
        return None
    if isinstance(x, (dict, list, tuple, set)):
        # stable textual form for complex values
        return json.dumps(x, ensure_ascii=False)
    return str(x)

def _strify_list(x):
    if x is None:
        return None
    if not isinstance(x, list):
        x = [x]
    return [_strify_scalar(v) for v in x]


def split_id_filename(key: str):
    """Split '002125_filename.ext' into ('002125', 'filename.ext') if possible."""
    if "_" in key:
        id_part, filename = key.split("_", 1)
        return id_part, filename
    return None, key  # no obvious ID; put the whole key as filename

def norm_list(x, *, default_empty_list=True):
    if x is None:
        return [] if default_empty_list else None
    if isinstance(x, list):
        return x
    # tolerate single item -> list
    return [x]

def coalesce(a, b):
    """Merge dictionaries with 'a' taking precedence where keys overlap."""
    out = dict(b or {})
    out.update(a or {})
    return out

def normalize_column(col_name: str, col_payload: Dict[str, Any]) -> Dict[str, Any]:
    # Normalize keys, handle weird VALUES’ key variants
    payload = {}
    weird_values_keys = [k for k in col_payload.keys() if str(k).strip("’'\"").upper() == "VALUES"]
    for k, v in (col_payload or {}).items():
        key_up = str(k).strip().upper().strip("’\"")
        if key_up == "VALUES" or k in weird_values_keys:
            payload["VALUES"] = v
        else:
            payload[key_up] = v

    base = DEFAULT_COLUMN.copy()
    base.update(payload)

    # Coerce heterogeneous fields to stable types
    checks = _strify_list(base.get("CHECKS")) or []
    values = _strify_list(base.get("VALUES"))  # None or list[str]
    default_val = _strify_scalar(base.get("DEFAULT"))
    ctype = _strify_scalar(base.get("TYPE"))

    normalized = {
        "NAME": col_name,
        "TYPE": ctype,
        "NULLABLE": bool(base.get("NULLABLE", True)),
        "UNIQUE": bool(base.get("UNIQUE", False)),
        "DEFAULT": default_val,
        "CHECKS": checks,
        "IS_PRIMARY": bool(base.get("IS_PRIMARY", False)),
        "IS_INDEX": bool(base.get("IS_INDEX", False)),
        "VALUES": values,
    }
    return normalized


def normalize_table(table_name: str, table_payload: Dict[str, Any]) -> Dict[str, Any]:
    tp = {(k.strip().upper() if isinstance(k, str) else k): v
          for k, v in (table_payload or {}).items()}

    columns_obj = tp.get("COLUMNS", {}) or {}
    columns_list: List[Dict[str, Any]] = []

    if isinstance(columns_obj, dict):
        for col_name, col_payload in columns_obj.items():
            columns_list.append(normalize_column(str(col_name), col_payload or {}))
    elif isinstance(columns_obj, list):
        for c in columns_obj:
            if isinstance(c, dict):
                col_name = (
                    c.get("NAME") or c.get("name") or
                    c.get("COLUMN_NAME") or c.get("column_name") or "unknown"
                )
                columns_list.append(normalize_column(str(col_name), c or {}))

    base = DEFAULT_TABLE.copy()
    base["PRIMARY_KEYS"] = list(base.get("PRIMARY_KEYS", [])) + list(tp.get("PRIMARY_KEYS", []) or [])
    base["FOREIGN_KEYS"] = list(tp.get("FOREIGN_KEYS", []) or [])
    base["CHECKS"] = list(tp.get("CHECKS", []) or [])
    base["INDEXES"] = list(tp.get("INDEXES", []) or [])

    # Normalize FKs
    norm_fks = []
    for fk in base["FOREIGN_KEYS"]:
        if not isinstance(fk, dict):
            continue
        fk_up = {(k.strip().upper() if isinstance(k, str) else k): v for k, v in fk.items()}
        norm_fks.append({
            "COLUMNS": _strify_list(fk_up.get("COLUMNS")) or [],
            "FOREIGN_TABLE": _strify_scalar(fk_up.get("FOREIGN_TABLE")),
            "REFERRED_COLUMNS": _strify_list(fk_up.get("REFERRED_COLUMNS")) or [],
            "ON_DELETE": _strify_scalar(fk_up.get("ON_DELETE")),
            "ON_UPDATE": _strify_scalar(fk_up.get("ON_UPDATE")),
        })

    # ✅ Use the new normalizer here
    norm_pks = _normalize_index_like(base["PRIMARY_KEYS"])
    norm_indexes = _normalize_index_like(base["INDEXES"])

    return {
        "TABLE_NAME": table_name,
        "COLUMNS": columns_list,
        "PRIMARY_KEYS": norm_pks,
        "FOREIGN_KEYS": norm_fks,
        "CHECKS": _strify_list(base["CHECKS"]) or [],
        "INDEXES": norm_indexes,
    }

def normalize_record(key: str, payload: Dict[str, Any]) -> Dict[str, Any]:
    id_part, filename = split_id_filename(key)

    # Merge INFO with synthesized fields
    info_in = payload.get("INFO", {}) or {}
    info_norm = dict(info_in)  # shallow copy
    if id_part:
        info_norm.setdefault("ID", id_part)
    info_norm.setdefault("FILENAME", filename)

    # Normalize TABLES -> list of tables
    tables_obj = payload.get("TABLES", {}) or {}
    tables_list = []
    if isinstance(tables_obj, dict):
        for tname, tpayload in tables_obj.items():
            tables_list.append(normalize_table(tname, tpayload or {}))
    elif isinstance(tables_obj, list):
        # Already a list; ensure each is normalized and has TABLE_NAME
        for t in tables_obj:
            if isinstance(t, dict):
                tname = t.get("TABLE_NAME") or t.get("name") or "unknown"
                tables_list.append(normalize_table(tname, t))

    normalized = {
        "ID": info_norm.get("ID", None),
        "FILENAME": info_norm.get("FILENAME", None),
        "URL": info_in.get("URL", None),
        "LICENSE": info_in["LICENSE"] if "LICENSE" in info_in else "UNKNOWN",
        "PERMISSIVE": bool(info_in.get("PERMISSIVE", False)),
        "TABLES": tables_list,
    }
    return normalized

def transform(data: Dict[str, Any]) -> List[Dict[str, Any]]:
    if not isinstance(data, dict):
        raise ValueError("Expected top-level object to be a dict mapping keys like '002125_filename' to records.")
    out: List[Dict[str, Any]] = []
    for key, payload in data.items():
        out.append(normalize_record(str(key), payload or {}))
    return out

# -------- CLI --------

def main():

    with gzip.open("schemapile-perm.json.gz", "rt", encoding="utf-8") as f:
        data = json.loads(f.read())
    records = transform(data)

    # Emit
    fh = open("data.jsonl", "w", encoding="utf-8")
    close = True

    try:
        for rec in records:
            fh.write(json.dumps(rec, ensure_ascii=False) + "\n")
    finally:
        if close:
            fh.close()

    # Upload to Hugging Face Hub using the datasets library

    # Load the JSONL file into a Hugging Face Dataset
    dataset = Dataset.from_json("data.jsonl")

if __name__ == "__main__":
    main()