from __future__ import annotations
from typing import Dict, Optional
import polars as pl
from tools.base import BaseTool


class TextInputTool(BaseTool):
    def execute(self, inputs: Dict[str, pl.DataFrame]) -> Dict[str, pl.DataFrame]:
        if self.config is None:
            return {"Output": pl.DataFrame()}

        fields = [
            f.attrib["name"]
            for f in self.config.findall("Fields/Field")
        ]
        if not fields:
            return {"Output": pl.DataFrame()}

        rows: list[dict] = []
        for r in self.config.findall("Data/r"):
            cells = r.findall("c")
            row: dict[str, Optional[str]] = {}
            for i, col_name in enumerate(fields):
                el = cells[i] if i < len(cells) else None
                text: Optional[str] = el.text if el is not None else None
                # Empty text in XML → NULL
                row[col_name] = text if text else None
            rows.append(row)

        if not rows:
            schema = {f: pl.String for f in fields}
            return {"Output": pl.DataFrame(schema=schema)}

        df = pl.DataFrame(rows, schema={f: pl.String for f in fields})
        return {"Output": df}