#!/usr/bin/env python3
from __future__ import annotations

import argparse
import importlib.util
import importlib
import json
import os
import subprocess
import sys
from pathlib import Path
from typing import Any

from scripts.benchmark_preflight import build_readiness_report
from scripts.hf_routing import resolve_routing


REPO_ROOT = Path(__file__).resolve().parents[1]
FREEZE_PATH = REPO_ROOT / "artifacts" / "cycle_1_execution_freeze.json"
RUNNER_PATH = REPO_ROOT / "scripts" / "benchmark_runner.py"


def active_hf_token() -> str | None:
    token = os.environ.get("HF_TOKEN")
    if token:
        return token
    try:
        from huggingface_hub.utils import get_token
        return get_token()
    except Exception:
        return None


def missing_benchmark_dependencies() -> list[str]:
    required = ["mamba_ssm", "transformers"]
    missing: list[str] = []
    for name in required:
        try:
            spec = importlib.util.find_spec(name)
        except (ImportError, ValueError):
            spec = None
        if spec is None:
            try:
                importlib.import_module(name)
            except Exception:
                missing.append(name)
    return missing


def load_cycle_freeze(path: Path) -> dict[str, Any]:
    return json.loads(path.read_text(encoding="utf-8"))


def load_cycle_benchmarks(path: Path) -> list[str]:
    payload = json.loads(path.read_text(encoding="utf-8"))
    out: list[str] = []
    for section in ("coding_benchmarks", "reasoning_benchmarks"):
        for slot in ("fast_iteration", "milestone"):
            entry = payload.get(section, {}).get(slot)
            if isinstance(entry, dict) and entry.get("name"):
                out.append(str(entry["name"]))
    return out


def build_preflight_report(
    *,
    cache_dir: Path,
    output_repo: str | None = None,
    tokenizer_repo: str | None = None,
) -> dict[str, object]:
    return build_readiness_report(
        cache_dir=cache_dir,
        hf_token_present=bool(active_hf_token()),
        dependencies_present=not bool(missing_benchmark_dependencies()),
        missing_dependencies=missing_benchmark_dependencies(),
        output_repo=output_repo,
        tokenizer_repo=tokenizer_repo,
    )


def write_preflight_report(path: Path, payload: dict[str, object]) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(json.dumps(payload, indent=2, sort_keys=True), encoding="utf-8")


def write_cycle_summary(path: Path, payload: list[dict[str, Any]]) -> None:
    path.parent.mkdir(parents=True, exist_ok=True)
    path.write_text(json.dumps(payload, indent=2, sort_keys=True), encoding="utf-8")


def build_remote_checkpoint_report(output_repo: str, token: str | None) -> dict[str, Any]:
    from huggingface_hub import HfApi

    from scripts.benchmark_checkpoint_report import build_checkpoint_report

    files = HfApi(token=token).list_repo_files(repo_id=output_repo, repo_type="model", token=token)
    return build_checkpoint_report(files)


def ensure_benchmark_assets(
    *,
    cache_dir: Path,
    output_repo: str,
    tokenizer_repo: str,
    token: str | None,
    hydrate: bool,
) -> dict[str, str] | None:
    if not hydrate:
        return None
    from scripts.benchmark_assets import hydrate_benchmark_assets

    return hydrate_benchmark_assets(
        cache_dir=cache_dir,
        output_repo=output_repo,
        tokenizer_repo=tokenizer_repo,
        token=token,
    )


def build_benchmark_command(
    freeze: dict[str, Any],
    *,
    benchmark: str,
    variant: str,
    seed: int,
    out_dir: Path,
) -> tuple[list[str], dict[str, str]]:
    variant_cfg = freeze["variants"][variant]
    env = os.environ.copy()
    env.update({str(k): str(v) for k, v in variant_cfg.get("env", {}).items()})
    env["HYDRA_SEED"] = str(seed)

    out_dir.mkdir(parents=True, exist_ok=True)
    result_path = out_dir / f"{benchmark.lower()}_{variant}_seed{seed}.json"
    ledger_path = out_dir / "benchmark_ledger.json"
    cmd = [
        sys.executable,
        str(RUNNER_PATH),
        "--benchmark",
        benchmark,
        "--generator-mode",
        "hydra",
        "--out",
        str(result_path),
        "--ledger",
        str(ledger_path),
        "--variant",
        variant,
        "--seed",
        str(seed),
    ]
    return cmd, env


def build_cycle_plan(freeze: dict[str, Any], *, benchmark: str, out_dir: Path) -> list[dict[str, Any]]:
    runnable_variants = [
        name for name, cfg in freeze.get("variants", {}).items()
        if isinstance(cfg, dict) and cfg.get("status") == "runnable_now"
    ]
    seeds = [int(seed) for seed in freeze.get("seeds", [])]
    plan: list[dict[str, Any]] = []
    for variant in runnable_variants:
        for seed in seeds:
            cmd, env = build_benchmark_command(
                freeze,
                benchmark=benchmark,
                variant=variant,
                seed=seed,
                out_dir=out_dir,
            )
            plan.append({
                "benchmark": benchmark,
                "variant": variant,
                "seed": seed,
                "command": cmd,
                "env": env,
            })
    return plan


def execute_cycle_plan(plan: list[dict[str, Any]], *, repo_root: Path) -> list[dict[str, Any]]:
    results: list[dict[str, Any]] = []
    for item in plan:
        proc = subprocess.run(item["command"], cwd=str(repo_root), env=item["env"])
        results.append(
            {
                "benchmark": item["benchmark"],
                "variant": item["variant"],
                "seed": item["seed"],
                "returncode": proc.returncode,
            }
        )
    return results


def parse_args(argv: list[str] | None = None) -> argparse.Namespace:
    parser = argparse.ArgumentParser(description="Execute a frozen Cycle 1 benchmark run")
    parser.add_argument("--freeze", type=Path, default=FREEZE_PATH)
    parser.add_argument("--suite", type=Path, default=REPO_ROOT / "artifacts" / "benchmark_suite.cycle1.json")
    parser.add_argument("--benchmark", required=True)
    parser.add_argument("--variant", required=True)
    parser.add_argument("--seed", type=int, required=True)
    parser.add_argument("--out-dir", type=Path, default=REPO_ROOT / "artifacts" / "runs")
    parser.add_argument("--preflight-out", type=Path)
    parser.add_argument("--summary-out", type=Path)
    parser.add_argument("--hydrate-assets", action="store_true")
    parser.add_argument("--all-runnable", action="store_true")
    parser.add_argument("--all-benchmarks", action="store_true")
    parser.add_argument("--require-ready", action="store_true")
    parser.add_argument("--output-repo")
    parser.add_argument("--tokenizer-repo")
    return parser.parse_args(argv)


def main(argv: list[str] | None = None) -> int:
    args = parse_args(argv)
    cache_dir = Path(os.path.expanduser("~/.cache/autoresearch"))
    report = None
    token = active_hf_token()
    routing = resolve_routing(token=token)
    output_repo = args.output_repo or routing.output_repo
    tokenizer_repo = args.tokenizer_repo or routing.output_repo
    if args.hydrate_assets:
        try:
            ensure_benchmark_assets(
                cache_dir=cache_dir,
                output_repo=output_repo,
                tokenizer_repo=tokenizer_repo,
                token=token,
                hydrate=True,
            )
        except FileNotFoundError as exc:
            checkpoint_report = None
            try:
                checkpoint_report = build_remote_checkpoint_report(output_repo, token)
            except Exception:
                checkpoint_report = None
            if args.summary_out is not None:
                write_cycle_summary(
                    args.summary_out,
                    [{
                        "status": "blocked",
                        "reason": "asset_hydration_failed",
                        "error": str(exc),
                        "checkpoint_candidates": checkpoint_report,
                    }],
                )
            return 3
    if args.preflight_out is not None:
        report = build_preflight_report(
            cache_dir=cache_dir,
            output_repo=output_repo,
            tokenizer_repo=tokenizer_repo,
        )
        write_preflight_report(args.preflight_out, report)
    if args.require_ready:
        if report is None:
            report = build_preflight_report(
                cache_dir=cache_dir,
                output_repo=output_repo,
                tokenizer_repo=tokenizer_repo,
            )
        if not bool(report.get("ready_for_hydra_benchmarks")):
            checkpoint_report = None
            try:
                checkpoint_report = build_remote_checkpoint_report(output_repo, token)
            except Exception:
                checkpoint_report = None
            if args.summary_out is not None:
                write_cycle_summary(
                    args.summary_out,
                    [{
                        "status": "blocked",
                        "reason": "preflight_not_ready",
                        "preflight": report,
                        "checkpoint_candidates": checkpoint_report,
                    }],
                )
            return 2
    freeze = load_cycle_freeze(args.freeze)
    if args.all_runnable:
        benchmarks = load_cycle_benchmarks(args.suite) if args.all_benchmarks else [args.benchmark]
        plan = []
        for benchmark in benchmarks:
            plan.extend(build_cycle_plan(freeze, benchmark=benchmark, out_dir=args.out_dir))
        results = execute_cycle_plan(plan, repo_root=REPO_ROOT)
        if args.summary_out is not None:
            write_cycle_summary(args.summary_out, results)
        return 0 if all(item["returncode"] == 0 for item in results) else 1
    cmd, env = build_benchmark_command(
        freeze,
        benchmark=args.benchmark,
        variant=args.variant,
        seed=args.seed,
        out_dir=args.out_dir,
    )
    proc = subprocess.run(cmd, cwd=str(REPO_ROOT), env=env)
    if args.summary_out is not None:
        write_cycle_summary(
            args.summary_out,
            [{
                "benchmark": args.benchmark,
                "variant": args.variant,
                "seed": args.seed,
                "returncode": proc.returncode,
            }],
        )
    return proc.returncode


if __name__ == "__main__":
    raise SystemExit(main())