# -*- coding: utf-8 -*-
"""
Anthropic Claude provider for itsulu_blog_publisher.

Supports:
- Standard Anthropic API keys (sk-ant-api03-...)
- Claude Pro user account API tokens (claude.ai/api tokens — same endpoint,
  different rate limits; treated identically here)

Uses raw HTTP (requests) rather than the anthropic SDK to avoid adding a hard
dependency. The SDK can be used optionally if installed.

Web search: Anthropic does not natively offer a web-search tool in the base
API. We instruct the model to cite real sources from its training knowledge
and note that the caller should verify URLs. When the 'web_search' beta tool
becomes generally available it can be enabled via the tools parameter.
"""
import json
import logging
import requests
from odoo.exceptions import UserError

_logger = logging.getLogger(__name__)

ANTHROPIC_API_URL = 'https://api.anthropic.com/v1/messages'
ANTHROPIC_API_VERSION = '2023-06-01'

# Anthropic model aliases accepted by this addon
KNOWN_ANTHROPIC_MODELS = {
    # Sonnet 4 family
    'claude-sonnet-4-20250514': 'claude-sonnet-4-20250514',
    'claude-sonnet-4':          'claude-sonnet-4-20250514',
    # Opus 4
    'claude-opus-4-20250514':   'claude-opus-4-20250514',
    'claude-opus-4':            'claude-opus-4-20250514',
    # Haiku 4.5
    'claude-haiku-4-5':         'claude-haiku-4-5-20251001',
    'claude-haiku-4-5-20251001':'claude-haiku-4-5-20251001',
    # Legacy / fallback
    'claude-3-5-sonnet-20241022':'claude-3-5-sonnet-20241022',
    'claude-3-5-haiku-20241022': 'claude-3-5-haiku-20241022',
    'claude-3-opus-20240229':    'claude-3-opus-20240229',
}


class AnthropicProvider:
    """
    Calls the Anthropic Messages API with a single user message.
    Returns (raw_text: str, tokens_used: int).
    """

    def __init__(self, api_key: str, model: str):
        self.api_key = api_key
        # Resolve model aliases; fall through to the literal string if unknown
        self.model = KNOWN_ANTHROPIC_MODELS.get(model, model)

    def generate(self, system_prompt: str, user_prompt: str) -> tuple:
        """
        :returns: (raw_text, tokens_used)
        :raises UserError: on HTTP error or non-2xx response
        """
        headers = {
            'x-api-key': self.api_key,
            'anthropic-version': ANTHROPIC_API_VERSION,
            'content-type': 'application/json',
            # Enable extended thinking / web search betas when available:
            # 'anthropic-beta': 'web-search-2025-03-05',
        }

        payload = {
            'model': self.model,
            'max_tokens': 4096,
            'system': system_prompt,
            'messages': [
                {'role': 'user', 'content': user_prompt}
            ],
        }

        _logger.debug("AnthropicProvider calling %s with model %s", ANTHROPIC_API_URL, self.model)

        try:
            resp = requests.post(
                ANTHROPIC_API_URL,
                headers=headers,
                json=payload,
                timeout=120,   # blog generation can take up to 2 minutes on Opus
            )
        except requests.Timeout:
            raise UserError(
                "Anthropic API request timed out after 120 seconds. "
                "Try a faster model (Haiku or Sonnet) or reduce the prompt length."
            )
        except requests.RequestException as exc:
            raise UserError(f"Anthropic API network error: {exc}") from exc

        if resp.status_code == 401:
            raise UserError(
                "Anthropic API returned 401 Unauthorized. "
                "Check your API key or Pro account token in Settings → Blog Publisher."
            )
        if resp.status_code == 429:
            raise UserError(
                "Anthropic API rate limit reached (429). "
                "Wait a moment and retry, or switch to a different model or provider."
            )
        if not resp.ok:
            try:
                err_detail = resp.json().get('error', {}).get('message', resp.text[:300])
            except Exception:
                err_detail = resp.text[:300]
            raise UserError(
                f"Anthropic API error {resp.status_code}: {err_detail}"
            )

        data = resp.json()
        content_blocks = data.get('content', [])
        raw_text = ''.join(
            block.get('text', '')
            for block in content_blocks
            if block.get('type') == 'text'
        )

        usage = data.get('usage', {})
        tokens_used = (
            usage.get('input_tokens', 0) + usage.get('output_tokens', 0)
        )

        _logger.info(
            "AnthropicProvider: model=%s input_tokens=%d output_tokens=%d",
            self.model,
            usage.get('input_tokens', 0),
            usage.get('output_tokens', 0),
        )

        return raw_text, tokens_used