"""Local test for GRPO training with SQLEnvTRL.

Usage:
    docker build -f Dockerfile.test -t sqlenv-test .
    docker run sqlenv-test
    docker run sqlenv-test python scripts/test_training_local.py \
        --config configs/colab_l4.json
"""

from __future__ import annotations

import argparse
import json
import os
import sys
from pathlib import Path

os.environ["CUDA_VISIBLE_DEVICES"] = os.environ.get("CUDA_VISIBLE_DEVICES", "")

root = Path(__file__).parent.parent
sys.path.insert(0, str(root))


def load_config(path: str) -> dict:
    with open(path) as f:
        return json.load(f)


def main() -> None:
    parser = argparse.ArgumentParser()
    parser.add_argument(
        "--config",
        default="configs/test_cpu.json",
        help="Training config JSON",
    )
    args = parser.parse_args()

    cfg = load_config(args.config)
    print(f"Config: {args.config}")
    print(json.dumps(cfg, indent=2))

    import transformers
    import trl
    from datasets import Dataset
    from trl import GRPOConfig, GRPOTrainer

    from sql_env.training.trl_adapter import (
        SQLEnvTRL,
        sql_env_reward_func,
    )

    print(f"\nTRL: {trl.__version__}, Transformers: {transformers.__version__}")

    # 1. Configure environment
    SQLEnvTRL._configure(
        questions_path=cfg["questions_path"],
        db_dir=cfg["db_dir"],
        step_budget=cfg["step_budget"],
    )
    env = SQLEnvTRL()
    obs = env.reset()
    print("\n--- Environment smoke test ---")
    print(f"Reset: {obs}")
    r = env.describe(table_name="employee")
    print(f"Describe: {r[:80]}")
    r = env.query(sql="SELECT COUNT(*) FROM employee")
    print(f"Query: {r}")
    r = env.answer(value="10")
    print(f"Answer: {r}")
    print(f"Total reward: {env.reward:.4f}")

    # 2. Dataset
    enable_thinking = cfg.get("enable_thinking", False)
    system_prompt_base = (
        "You answer questions about a SQL database. "
        "Use ONLY the provided tools.\n\n"
        "Strategy:\n"
        "1. Call describe(table_name=...) to see columns\n"
        "2. Call query(sql=...) to run SELECT queries\n"
        "3. Call answer(value=...) to submit your answer"
    )
    system_prompt = (
        system_prompt_base if enable_thinking else "/no_think\n" + system_prompt_base
    )
    questions = [
        "How many employees are there?",
        "What are the names of all shops?",
        "Find the total number of concerts.",
        "List all singer names.",
    ]
    prompt_msgs = [
        [
            {"role": "system", "content": system_prompt},
            {"role": "user", "content": q},
        ]
        for q in questions
    ]
    size = cfg.get("dataset_size", len(prompt_msgs))
    repeated = (prompt_msgs * ((size // len(prompt_msgs)) + 1))[:size]
    repeated_q = (questions * ((size // len(questions)) + 1))[:size]
    dataset = Dataset.from_dict({"prompt": repeated, "question_text": repeated_q})

    # 3. Trainer config
    print("\n--- Building trainer ---")
    grpo_kwargs = {
        "output_dir": cfg["output_dir"],
        "per_device_train_batch_size": cfg["per_device_train_batch_size"],
        "num_generations": cfg["num_generations"],
        "num_train_epochs": cfg["num_train_epochs"],
        "max_completion_length": cfg["max_completion_length"],
        "logging_steps": cfg["logging_steps"],
        "log_completions": True,
        "num_completions_to_print": cfg.get("num_completions_to_print", 2),
        "remove_unused_columns": False,
    }
    if cfg.get("max_steps"):
        grpo_kwargs["max_steps"] = cfg["max_steps"]
    grpo_kwargs["chat_template_kwargs"] = {
        "enable_thinking": enable_thinking,
    }

    precision = cfg.get("precision", "fp32")
    if precision == "bf16":
        grpo_kwargs.update(bf16=True, fp16=False)
    elif precision == "fp16":
        grpo_kwargs.update(bf16=False, fp16=True)
    else:
        grpo_kwargs.update(bf16=False, fp16=False)

    trainer = GRPOTrainer(
        model=cfg["model_name"],
        reward_funcs=sql_env_reward_func,
        train_dataset=dataset,
        environment_factory=SQLEnvTRL,
        args=GRPOConfig(**grpo_kwargs),
    )

    # 4. Train
    print(f"\n--- Training ({cfg.get('max_steps', 'all')} steps) ---")
    trainer.train()

    # 5. Results
    print("\n--- Results ---")
    for entry in trainer.state.log_history:
        step = entry.get("step")
        loss = entry.get("loss")
        if loss is None:
            continue
        reward = entry.get("reward", 0)
        reward_std = entry.get("reward_std", 0)
        tools_freq = entry.get("tools/call_frequency", 0)
        clipped = entry.get("completions/clipped_ratio", 0)
        mean_len = entry.get("completions/mean_length", 0)
        print(
            f"Step {step:>3}: "
            f"loss={loss:.4f}  "
            f"reward={reward:.4f} +/-{reward_std:.4f}  "
            f"tools={tools_freq:.2f}  "
            f"clipped={clipped:.0%}  "
            f"len={mean_len:.0f}"
        )

    losses = [e["loss"] for e in trainer.state.log_history if "loss" in e]
    rewards = [e.get("reward", 0) for e in trainer.state.log_history if "loss" in e]

    print(f"\nLoss:   {losses}")
    print(f"Reward: {rewards}")

    if losses and any(v != 0.0 for v in losses):
        print("\nSUCCESS: Non-zero training loss")
    else:
        print("\nFAILED: All losses zero")

    if rewards and any(v != 0.0 for v in rewards):
        print("SUCCESS: Non-zero rewards")
    else:
        print("FAILED: All rewards zero")


if __name__ == "__main__":
    main()