import os
import json
from pathlib import Path
from typing import List, Dict, Any
from datetime import datetime

from .core import PlanDelta


class DeltaStore:
    def __init__(self, path: str = ".exoroute_deltas"):
        self.path = Path(path)
        self.path.mkdir(parents=True, exist_ok=True)
        self.log_file = self.path / "deltas.log"
        if not self.log_file.exists():
            self.log_file.write_text("")

    def append_delta(self, delta: PlanDelta) -> None:
        entry = {
            "delta": delta.delta,
            "timestamp": delta.timestamp,
            "author": delta.author,
            "contract_id": delta.contract_id,
            "signature": delta.signature,
        }
        with self.log_file.open("a", encoding="utf-8") as f:
            f.write(json.dumps(entry, sort_keys=True) + "\n")

    def read_deltas(self) -> List[Dict[str, Any]]:
        if not self.log_file.exists():
            return []
        deltas = []
        with self.log_file.open("r", encoding="utf-8") as f:
            for line in f:
                line = line.strip()
                if not line:
                    continue
                try:
                    deltas.append(json.loads(line))
                except json.JSONDecodeError:
                    continue
        return deltas

    def clear(self) -> None:
        self.log_file.write_text("")