"""Prompt loader for AI agents.

Loads prompts from agent spec files or YAML configuration.
"""

import re
from pathlib import Path
from typing import Any, Optional

import yaml

AGENT_SPECS_DIR = Path("docs/specs/agents")
AGENT_PROMPTS_YAML = Path("docs/agent_prompts.yaml")


def get_agent_roles() -> list[str]:
    """Get all available agent roles."""
    roles = []
    if AGENT_PROMPTS_YAML.exists():
        data = yaml.safe_load(AGENT_PROMPTS_YAML.read_text(encoding="utf-8"))
        return list(data.keys()) if data else []

    if AGENT_SPECS_DIR.exists():
        for f in sorted(AGENT_SPECS_DIR.glob("*.md")):
            roles.append(f.stem)

    return roles


def load_prompt_from_yaml(role: str) -> Optional[dict[str, Any]]:
    """Load prompt config from YAML file."""
    if not AGENT_PROMPTS_YAML.exists():
        return None

    data = yaml.safe_load(AGENT_PROMPTS_YAML.read_text(encoding="utf-8"))
    return data.get(role) if data else None


def load_prompt_from_spec(role: str) -> Optional[dict[str, Any]]:
    """Load prompt from agent spec markdown file."""
    spec_path = AGENT_SPECS_DIR / f"{role}.md"
    if not spec_path.exists():
        return None

    content = spec_path.read_text(encoding="utf-8")

    def extract_field(label: str) -> Optional[str]:
        match = re.search(rf"\*\*{label}:\*\*\s*(.+)", content)
        return match.group(1).strip() if match else None

    def extract_prompt() -> Optional[str]:
        match = re.search(
            r"## Prompt Template\n+```\n(.+?)\n```",
            content,
            re.DOTALL,
        )
        return match.group(1).strip() if match else None

    provider_str = extract_field("Провайдер") or extract_field("Provider") or "yandex_gpt"
    provider = "gigachat" if "gigachat" in (provider_str or "").lower() else "yandex_gpt"

    prompt_text = extract_prompt()
    if not prompt_text:
        return None

    return {
        "system_prompt": prompt_text,
        "provider": provider,
        "temperature": 0.7,
        "max_tokens": 2000,
    }


def get_prompt_config(role: str) -> Optional[dict[str, Any]]:
    """Get prompt configuration for a role.

    Tries YAML first, falls back to spec markdown.

    Args:
        role: Agent role name (e.g. "coordinator", "business_analyst")

    Returns:
        Dict with keys: system_prompt, provider, temperature, max_tokens
        or None if not found.
    """
    config = load_prompt_from_yaml(role)
    if config:
        return config

    return load_prompt_from_spec(role)