from __future__ import annotations

import json
import re

from .llm import call_llm
from .paths import CHAR_PATH, WORLD_PATH
from . import state


VALIDATION_PROMPT = """You are a strict RPG game master validating whether a player's action is possible given the game state. Be thorough — check inventory, stats, location, NPCs, story context, and story logic.

## Character
{character}

## World
{world}

## Session Log
*Written in 3rd person with explicit actor names.*
{log}

## Recent Story
*Written in 3rd person with explicit actor names.*
{story}

## Player Action
{action}

## Instructions
- Is the player trying to use an item they don't have? -> invalid
- Are they asserting something that contradicts the state? -> invalid
- Is the action nonsensical given the situation? -> invalid
- Does the action make sense given the character's abilities and resources? -> valid
- Pay close attention to the Recent Story section — entities like monsters, NPCs, and hazards currently present in the scene ARE valid targets for action.
- If valid, also check: if they're using a consumable item, note that it must be removed from inventory.

Reply with ONLY the JSON object. Examples:
```
{{"valid": true, "reason": "ok"}}
```
or
```
{{"valid": false, "reason": "brief explanation of why the action is impossible"}}
```
"""


def validate_action(
    player_action: str,
    *,
    story: str = "",
    log: str = "",
    on_debug: callable = None,
) -> tuple[bool, str]:
    """Ask the LLM whether a player action is valid given the game state. Returns (valid, reason)."""
    if not player_action:
        return True, ""

    char = state.read_file(CHAR_PATH) or "*No character sheet.*"
    world = state.truncate_world(state.read_file(WORLD_PATH) or "") or "*No world state.*"
    recent = story.strip() or state.read_recent_book() or "*No prior story.*"
    log_entries = log.strip() or state.read_recent_log() or "*No recent events.*"

    prompt = VALIDATION_PROMPT.format(character=char, world=world, log=log_entries, story=recent, action=player_action)

    text = call_llm(
        [{"role": "user", "content": prompt}],
        max_tokens=1024,
        temperature=0.2,
        label="Action validation",
        on_debug=on_debug,
    )

    if not text:
        return False, "Not sure"

    cleaned = text.strip()
    m = re.search(r"```(?:json)?\s*\n?(.*?)```", cleaned, re.DOTALL)
    if m:
        cleaned = m.group(1).strip()
    try:
        data = json.loads(cleaned)
        valid = data.get("valid", True)
        reason = data.get("reason", "")
        if on_debug:
            on_debug("action_validation", {"valid": valid, "reason": reason, "action": player_action})
        return valid, reason
    except (json.JSONDecodeError, ValueError):
        if on_debug:
            on_debug("action_validation", {"valid": True, "reason": "parse_failed", "raw": text[:200]})
        return False, "Unrecognized"


def auto_prompt(book_log: str = "") -> str:
    """Fallback player prompt."""
    return "**What do you do?**"