from __future__ import annotations

import argparse
import os
import json
import time
from pathlib import Path
from typing import Iterable, List, Dict, Any, Protocol, Tuple, Optional

# ---- app imports
from nl2sql.pipeline import Pipeline, FinalResult
from nl2sql.ambiguity_detector import AmbiguityDetector
from nl2sql.planner import Planner
from nl2sql.generator import Generator
from nl2sql.safety import Safety
from nl2sql.executor import Executor
from nl2sql.verifier import Verifier
from nl2sql.repair import Repair

# ---- adapters
from adapters.db.sqlite_adapter import SQLiteAdapter
from adapters.llm.openai_provider import OpenAIProvider


# ---- LLM protocol (unifies OpenAIProvider and DummyLLM for mypy)
class LLMProvider(Protocol):
    """Minimal interface required by Planner/Generator/Repair stages."""

    provider_id: str

    def plan(
        self, *, user_query: str, schema_preview: str
    ) -> Tuple[str, int, int, float]: ...

    def generate_sql(
        self,
        *,
        user_query: str,
        schema_preview: str,
        plan_text: str,
        clarify_answers: Optional[Any] = None,
    ) -> Tuple[str, str, int, int, float]: ...

    def repair(
        self, *, sql: str, error_msg: str, schema_preview: str
    ) -> Tuple[str, int, int, float]: ...


# ---- fallback: Dummy LLM (so it runs without API keys)
class DummyLLM:
    provider_id = "dummy-llm"

    def plan(
        self, *, user_query: str, schema_preview: str
    ) -> Tuple[str, int, int, float]:
        text = (
            f"- understand question: {user_query}\n"
            "- identify tables\n- join if needed\n- filter\n- order/limit"
        )
        return text, 0, 0, 0.0

    def generate_sql(
        self,
        *,
        user_query: str,
        schema_preview: str,
        plan_text: str,
        clarify_answers: Optional[Any] = None,
    ) -> Tuple[str, str, int, int, float]:
        # naive demo SQL (so pipeline flows end-to-end)
        sql = "SELECT 1 AS one;"
        rationale = "Demo SQL from DummyLLM"
        return sql, rationale, 0, 0, 0.0

    def repair(
        self, *, sql: str, error_msg: str, schema_preview: str
    ) -> Tuple[str, int, int, float]:
        return sql, 0, 0, 0.0


def ensure_demo_db(path: Path) -> None:
    """Create a tiny SQLite db if missing, so executor has something to run."""
    if path.exists():
        return
    import sqlite3

    path.parent.mkdir(parents=True, exist_ok=True)
    con = sqlite3.connect(path)
    cur = con.cursor()
    cur.execute("CREATE TABLE users(id INTEGER PRIMARY KEY, name TEXT, spend REAL);")
    cur.executemany(
        "INSERT INTO users(id,name,spend) VALUES(?,?,?)",
        [(1, "Alice", 120.5), (2, "Bob", 80.0), (3, "Carol", 155.0)],
    )
    con.commit()
    con.close()


def build_pipeline(db_path: Path, use_openai: bool) -> Pipeline:
    # DB adapter
    db = SQLiteAdapter(str(db_path))
    executor = Executor(db)

    # LLM provider (typed to the Protocol so mypy accepts either provider)
    llm: LLMProvider
    if use_openai and os.getenv("OPENAI_API_KEY"):
        llm = OpenAIProvider()  # conforms to LLMProvider
    else:
        llm = DummyLLM()  # conforms to LLMProvider

    # stages
    detector = AmbiguityDetector()
    planner = Planner(llm)
    generator = Generator(llm)
    safety = Safety()
    verifier = Verifier()
    repair = Repair(llm)

    # pipeline
    return Pipeline(
        detector=detector,
        planner=planner,
        generator=generator,
        safety=safety,
        executor=executor,
        verifier=verifier,
        repair=repair,
    )


def _sum_cost(traces: Iterable[Dict[str, Any]]) -> float:
    total = 0.0
    for tr in traces:
        try:
            total += float(tr.get("cost_usd", 0.0))
        except Exception:
            # ignore bad values
            pass
    return total


def _is_safe_fail(ok: bool, details: List[str] | None) -> float:
    """Return 1.0 when pipeline failed due to unsafe SQL (heuristic)."""
    if ok:
        return 0.0
    txt = " ".join(details or []).lower()
    return 1.0 if "unsafe" in txt else 0.0


def run_benchmark(
    queries: List[str], schema_preview: str, pipeline: Pipeline, outfile: Path
) -> None:
    results: List[Dict[str, Any]] = []
    for q in queries:
        t0 = time.perf_counter()
        res: FinalResult = pipeline.run(user_query=q, schema_preview=schema_preview)
        latency_ms = (time.perf_counter() - t0) * 1000.0

        ok = (not res.ambiguous) and (not res.error) and bool(res.ok)
        traces = res.traces or []
        cost_sum = _sum_cost(traces)

        results.append(
            {
                "query": q,
                "exec_acc": 1.0 if ok else 0.0,
                "safe_fail": _is_safe_fail(ok, res.details),
                "latency_ms": latency_ms,
                "cost_usd": cost_sum,
                "repair_attempts": sum(1 for t in traces if t.get("stage") == "repair"),
                "provider": getattr(
                    getattr(pipeline.generator, "llm", None), "provider_id", "unknown"
                ),
            }
        )

    outfile.parent.mkdir(parents=True, exist_ok=True)
    with open(outfile, "w") as f:
        for row in results:
            f.write(json.dumps(row) + "\n")
    print(f"[OK] wrote {len(results)} rows → {outfile}")


def main() -> None:
    parser = argparse.ArgumentParser()
    parser.add_argument("--outfile", default="benchmarks/results/demo.jsonl")
    parser.add_argument("--db", default="data/bench_demo.db")
    parser.add_argument(
        "--use-openai",
        action="store_true",
        help="Use OpenAI provider if API key present",
    )
    args = parser.parse_args()

    root = Path(__file__).resolve().parents[1]  # project root
    outfile = (root / args.outfile).resolve()
    db_path = (root / args.db).resolve()

    ensure_demo_db(db_path)
    pipe = build_pipeline(db_path, use_openai=args.use_openai)

    # a small demo set; replace with Spider when ready
    queries = [
        "show all users",
        "top spenders",
        "sum of spend",
    ]
    schema_preview = "CREATE TABLE users(id INT, name TEXT, spend REAL);"

    run_benchmark(queries, schema_preview, pipe, outfile)


if __name__ == "__main__":
    main()