import json
from datetime import datetime
from agentm.logic.db import get_db_conn


def get_cached_rom(rom_file: str) -> dict | None:
    """
    Retrieve verified ROM metadata from the database by ROM filename.

    Args:
        rom_file: The filename of the ROM (e.g., 'sfiii3n.zip').

    Returns:
        A dictionary of ROM metadata if verified, otherwise None.
    """
    with get_db_conn() as conn:
        cur = conn.execute("""
            SELECT sha256, verified_at, title, game_id,
                   difficulty_min, difficulty_max, characters, keywords
            FROM roms WHERE rom_file = ? AND verified = 1
        """, (rom_file,))
        row = cur.fetchone()

        if row:
            return {
                "sha256": row[0],
                "verified": True,
                "verified_at": row[1],
                "title": row[2],
                "rom_file": rom_file,
                "game_id": row[3],
                "difficulty_min": row[4],
                "difficulty_max": row[5],
                "characters": json.loads(row[6]) if row[6] else [],
                "keywords": json.loads(row[7]) if row[7] else [],
            }
        return None


def get_all_verified_roms() -> list[dict]:
    """
    Return a list of all verified ROMs as dictionaries.

    Returns:
        A list of dictionaries containing ROM metadata.
    """
    with get_db_conn() as conn:
        cur = conn.execute("""
            SELECT sha256, verified_at, title, game_id, rom_file,
                   difficulty_min, difficulty_max, characters, keywords
            FROM roms WHERE verified = 1
            ORDER BY title ASC
        """)
        rows = cur.fetchall()

        return [
            {
                "sha256": row[0],
                "verified": True,
                "verified_at": row[1],
                "title": row[2],
                "game_id": row[3],
                "rom_file": row[4],
                "difficulty_min": row[5],
                "difficulty_max": row[6],
                "characters": json.loads(row[7]) if row[7] else [],
                "keywords": json.loads(row[8]) if row[8] else [],
            }
            for row in rows
        ]


def upsert_rom_record(
    title: str,
    rom_file: str,
    game_id: str,
    sha256: str,
    difficulty_min: int = None,
    difficulty_max: int = None,
    characters: list[str] = None,
    keywords: list[str] = None
):
    """
    Insert or replace a verified ROM entry in the database.

    Args:
        title: Game title.
        rom_file: ROM file name.
        game_id: Game ID used by DIAMBRA.
        sha256: SHA256 checksum of the ROM.
        difficulty_min: Minimum difficulty.
        difficulty_max: Maximum difficulty.
        characters: List of characters.
        keywords: List of keywords.
    """
    with get_db_conn() as conn:
        conn.execute("""
            INSERT OR REPLACE INTO roms (
                title,
                rom_file,
                game_id,
                sha256,
                difficulty_min,
                difficulty_max,
                characters,
                keywords,
                verified,
                verified_at
            ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, 1, ?)
        """, (
            title,
            rom_file,
            game_id,
            sha256,
            difficulty_min,
            difficulty_max,
            json.dumps(characters or []),
            json.dumps(keywords or []),
            datetime.utcnow().isoformat()
        ))

def get_agents_for_game(game_id: str) -> list[dict]:
    """
    Retrieve all agents associated with a given game_id.

    Args:
        game_id: The unique game ID (e.g., 'sfiii3n').

    Returns:
        A list of agent metadata dictionaries.
    """
    with get_db_conn() as conn:
        cur = conn.execute("""
            SELECT id, name, game_id, created_at, last_updated, agent_type, framework, is_imitation
            FROM agents
            WHERE game_id = ?
            ORDER BY created_at DESC
        """, (game_id,))
        return [dict(row) for row in cur.fetchall()]


def insert_agent(
    name: str,
    game_id: str,
    config_json: str,
    agent_type: str = "PPO",
    framework: str = "SB3",
    is_imitation: bool = False,
    dataset_path: str = "",
    notes: str = ""
) -> None:
    """
    Insert a new agent into the database.

    Args:
        name: Agent name.
        game_id: Game ID this agent is associated with.
        config_json: JSON string of the training config.
        agent_type: Algorithm type (e.g., PPO, BC).
        framework: Framework name (e.g., SB3, Ray).
        is_imitation: Whether this is imitation learning.
        dataset_path: Optional path to dataset (for IL).
        notes: Developer notes or comments.
    """
    with get_db_conn() as conn:
        conn.execute("""
            INSERT INTO agents (
                name,
                game_id,
                config_json,
                agent_type,
                framework,
                is_imitation,
                dataset_path,
                notes,
                created_at,
                last_updated
            ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
        """, (
            name,
            game_id,
            config_json,
            agent_type,
            framework,
            int(is_imitation),
            dataset_path,
            notes,
            datetime.utcnow().isoformat(),
            datetime.utcnow().isoformat()
        ))

def delete_agent_by_id(agent_id: int) -> None:
    """
    Permanently delete an agent from the database by ID.

    Args:
        agent_id: The unique agent ID to delete.
    """
    with get_db_conn() as conn:
        conn.execute("DELETE FROM agents WHERE id = ?", (agent_id,))


def get_agent_by_id(agent_id: int) -> dict | None:
    """
    Fetch a single agent's metadata from the database by ID.

    Args:
        agent_id: The unique agent ID.

    Returns:
        A dictionary of agent metadata if found, otherwise None.
    """
    with get_db_conn() as conn:
        cur = conn.execute("""
            SELECT id, name, game_id, created_at, last_updated, agent_type,
                   framework, is_imitation, dataset_path, config_json, notes
            FROM agents
            WHERE id = ?
        """, (agent_id,))
        row = cur.fetchone()

        if row:
            return dict(row)
        return None

from datetime import datetime
from agentm.logic.db import get_db_conn


def insert_run(
    agent_id: int,
    name: str,
    config_yaml: str,
    notes: str = ""
) -> None:
    """
    Insert a new run associated with an agent.

    Args:
        agent_id: The agent this run belongs to.
        name: The name of the run.
        config_yaml: Serialized YAML config (frozen) for this run.
        notes: Optional notes about the run.
    """
    with get_db_conn() as conn:
        conn.execute("""
            INSERT INTO runs (
                agent_id,
                name,
                config_yaml,
                notes,
                created_at,
                updated_at
            ) VALUES (?, ?, ?, ?, ?, ?)
        """, (
            agent_id,
            name,
            config_yaml,
            notes,
            datetime.utcnow().isoformat(),
            datetime.utcnow().isoformat()
        ))


def get_runs_for_agent(agent_id: int) -> list[dict]:
    """
    Get all runs associated with a specific agent.

    Args:
        agent_id: The ID of the agent.

    Returns:
        A list of run dictionaries.
    """
    with get_db_conn() as conn:
        cur = conn.execute("""
            SELECT * FROM runs
            WHERE agent_id = ?
            ORDER BY created_at DESC
        """, (agent_id,))
        return [dict(row) for row in cur.fetchall()]


def get_run_by_id(run_id: int) -> dict | None:
    """
    Get a specific run by its ID.

    Args:
        run_id: The ID of the run.

    Returns:
        A run dictionary or None if not found.
    """
    with get_db_conn() as conn:
        cur = conn.execute("""
            SELECT * FROM runs
            WHERE id = ?
        """, (run_id,))
        row = cur.fetchone()
        return dict(row) if row else None


def delete_run_by_id(run_id: int) -> None:
    """
    Delete a run permanently from the database.

    Args:
        run_id: The ID of the run to delete.
    """
    with get_db_conn() as conn:
        conn.execute("""
            DELETE FROM runs
            WHERE id = ?
        """, (run_id,))

from datetime import datetime
from agentm.logic.db import get_db_conn

def insert_model(
    agent_id: int,
    name: str,
    total_steps_planned: int,
    notes: str = "",
    parent_model_id: int | None = None,
    average_reward: float | None = None,
    current_learning_rate: float | None = None,
    current_clip_range: float | None = None,
    config_patch_yaml: str = "",
    checkpoint_path: str = "",
    is_frozen: bool = False,
    status: str = "pending"
) -> None:
    """
    Insert a new model entry.
    """
    with get_db_conn() as conn:
        conn.execute("""
            INSERT INTO models (
                agent_id, parent_model_id, name, notes,
                total_steps_planned, total_steps_completed, average_reward,
                current_learning_rate, current_clip_range,
                config_patch_yaml, checkpoint_path, is_frozen,
                status, created_at, updated_at
            ) VALUES (?, ?, ?, ?, ?, 0, ?, ?, ?, ?, ?, ?, ?, ?, ?)
        """, (
            agent_id, parent_model_id, name, notes,
            total_steps_planned, average_reward,
            current_learning_rate, current_clip_range,
            config_patch_yaml, checkpoint_path, int(is_frozen),
            status, datetime.utcnow().isoformat(), datetime.utcnow().isoformat()
        ))

def get_models_for_agent(agent_id: int, include_children: bool = True) -> list[dict]:
    """
    Fetch models for a given agent.
    """
    with get_db_conn() as conn:
        cur = conn.execute("""
            SELECT * FROM models
            WHERE agent_id = ?
            ORDER BY created_at DESC
        """, (agent_id,))
        return [dict(row) for row in cur.fetchall()]

def get_model_by_id(model_id: int) -> dict | None:
    """
    Fetch a single model by ID.
    """
    with get_db_conn() as conn:
        cur = conn.execute("SELECT * FROM models WHERE id = ?", (model_id,))
        row = cur.fetchone()
        return dict(row) if row else None

def update_model_progress(
    model_id: int,
    total_steps_completed: int,
    average_reward: float | None = None,
    current_learning_rate: float | None = None,
    current_clip_range: float | None = None,
    checkpoint_path: str | None = None,
    status: str | None = None
):
    """
    Update step progress, learning rate, and optionally reward/checkpoint info.
    """
    fields = ["total_steps_completed = ?"]
    values = [total_steps_completed]

    if average_reward is not None:
        fields.append("average_reward = ?")
        values.append(average_reward)

    if current_learning_rate is not None:
        fields.append("current_learning_rate = ?")
        values.append(current_learning_rate)

    if current_clip_range is not None:
        fields.append("current_clip_range = ?")
        values.append(current_clip_range)

    if checkpoint_path is not None:
        fields.append("checkpoint_path = ?")
        values.append(checkpoint_path)

    if status is not None:
        fields.append("status = ?")
        values.append(status)

    fields.append("updated_at = ?")
    values.append(datetime.utcnow().isoformat())

    values.append(model_id)

    with get_db_conn() as conn:
        conn.execute(f"""
            UPDATE models SET {', '.join(fields)}
            WHERE id = ?
        """, tuple(values))

def delete_model_by_id(model_id: int) -> None:
    """
    Delete a model record.
    """
    with get_db_conn() as conn:
        conn.execute("DELETE FROM models WHERE id = ?", (model_id,))

def get_models_for_run(run_id: int) -> list[dict]:
    """
    Retrieve all models linked to a specific run.
    Assumes a run_id is passed and models were inserted with a reference to it (if applicable).
    Currently, models are linked by agent_id only, so we filter manually.

    Args:
        run_id: The ID of the run.

    Returns:
        A list of model dicts.
    """
    with get_db_conn() as conn:
        # First, get the agent_id for the run
        cur = conn.execute("SELECT agent_id FROM runs WHERE id = ?", (run_id,))
        row = cur.fetchone()
        if not row:
            return []

        agent_id = row["agent_id"]
        # Then, get all models for that agent
        cur = conn.execute("""
            SELECT * FROM models
            WHERE agent_id = ?
            ORDER BY created_at DESC
        """, (agent_id,))
        return [dict(r) for r in cur.fetchall()]


def update_run(
    run_id: int,
    name: str | None = None,
    config_yaml: str | None = None,
    notes: str | None = None,
    pending: bool | None = None
) -> None:
    """
    Update a run by ID with any combination of fields.
    """
    fields = []
    values = []

    if name is not None:
        fields.append("name = ?")
        values.append(name)

    if config_yaml is not None:
        fields.append("config_yaml = ?")
        values.append(config_yaml)

    if notes is not None:
        fields.append("notes = ?")
        values.append(notes)

    if pending is not None:
        fields.append("pending = ?")
        values.append(int(pending))

    if not fields:
        return  # Nothing to update

    fields.append("updated_at = ?")
    values.append(datetime.utcnow().isoformat())
    values.append(run_id)

    with get_db_conn() as conn:
        conn.execute(
            f"UPDATE runs SET {', '.join(fields)} WHERE id = ?",
            tuple(values)
        )

def update_run_pending(run_id: int, pending: bool) -> None:
    """
    Update the pending status of a run.

    Args:
        run_id: The ID of the run to update.
        pending: New pending status (True/False).
    """
    with get_db_conn() as conn:
        conn.execute("""
            UPDATE runs
            SET pending = ?, updated_at = ?
            WHERE id = ?
        """, (int(pending), datetime.utcnow().isoformat(), run_id))