"""
Flare – API Executor  (v2.0 · session-aware token management)
"""

from __future__ import annotations
import json, re, time, requests
from typing import Any, Dict, Optional, Union
import os

from utils.logger import log_info, log_error, log_warning, log_debug, LogTimer
from config.config_provider import ConfigProvider, APIConfig
from chat_session.session import Session

MAX_RESPONSE_SIZE = 10 * 1024 * 1024  # 10MB
DEFAULT_TIMEOUT = int(os.getenv("API_TIMEOUT_SECONDS", "30"))

_placeholder = re.compile(r"\{\{\s*([^\}]+?)\s*\}\}")

def _get_variable_value(session: Session, var_path: str) -> Any:
    cfg = ConfigProvider.get()

    """Get variable value with proper type from session"""
    if var_path.startswith("variables."):
        var_name = var_path.split(".", 1)[1]
        return session.variables.get(var_name)
    elif var_path.startswith("auth_tokens."):
        parts = var_path.split(".")
        if len(parts) >= 3:
            token_api = parts[1]
            token_field = parts[2]
            token_data = session._auth_tokens.get(token_api, {})
            return token_data.get(token_field)
    elif var_path.startswith("config."):
        attr_name = var_path.split(".", 1)[1]
        return getattr(cfg.global_config, attr_name, None)
    return None

def _render_value(value: Any) -> Union[str, int, float, bool, None]:
    """Convert value to appropriate JSON type"""
    if value is None:
        return None
    elif isinstance(value, bool):
        return value
    elif isinstance(value, (int, float)):
        return value
    elif isinstance(value, str):
        # Check if it's a number string
        if value.isdigit():
            return int(value)
        try:
            return float(value)
        except ValueError:
            pass
        # Check if it's a boolean string
        if value.lower() in ('true', 'false'):
            return value.lower() == 'true'
        # Return as string
        return value
    else:
        return str(value)

def _render_json(obj: Any, session: Session, api_name: str) -> Any:
    """Render JSON preserving types"""
    if isinstance(obj, str):
        # Check if entire string is a template
        template_match = _placeholder.fullmatch(obj.strip())
        if template_match:
            # This is a pure template like {{variables.pnr}}
            var_path = template_match.group(1).strip()
            value = _get_variable_value(session, var_path)
            return _render_value(value)
        else:
            # String with embedded templates or regular string
            def replacer(match):
                var_path = match.group(1).strip()
                value = _get_variable_value(session, var_path)
                return str(value) if value is not None else ""

            return _placeholder.sub(replacer, obj)

    elif isinstance(obj, dict):
        return {k: _render_json(v, session, api_name) for k, v in obj.items()}

    elif isinstance(obj, list):
        return [_render_json(v, session, api_name) for v in obj]

    else:
        # Return as-is for numbers, booleans, None
        return obj

def _render(obj: Any, session: Session, api_name: str) -> Any:
    """Render template with session variables and tokens"""
    # For headers and other string-only contexts
    if isinstance(obj, str):
        def replacer(match):
            var_path = match.group(1).strip()
            value = _get_variable_value(session, var_path)
            return str(value) if value is not None else ""

        return _placeholder.sub(replacer, obj)

    elif isinstance(obj, dict):
        return {k: _render(v, session, api_name) for k, v in obj.items()}

    elif isinstance(obj, list):
        return [_render(v, session, api_name) for v in obj]

    return obj

def _fetch_token(api: APIConfig, session: Session) -> None:
    """Fetch new auth token"""
    if not api.auth or not api.auth.enabled:
        return

    log_info(f"🔑 Fetching token for {api.name}")

    try:
        # Use _render_json for body to preserve types
        body = _render_json(api.auth.token_request_body, session, api.name)
        headers = {"Content-Type": "application/json"}

        response = requests.post(
            str(api.auth.token_endpoint),
            json=body,
            headers=headers,
            timeout=api.timeout_seconds
        )
        response.raise_for_status()

        json_data = response.json()

        # Extract token using path
        token = json_data
        for path_part in api.auth.response_token_path.split("."):
            token = token.get(path_part)
            if token is None:
                raise ValueError(f"Token path {api.auth.response_token_path} not found in response")

        # Store in session
        session._auth_tokens[api.name] = {
            "token": token,
            "expiry": time.time() + 3500,  # ~1 hour
            "refresh_token": json_data.get("refresh_token")
        }

        log_info(f"✅ Token obtained for {api.name}")

    except Exception as e:
        log_error(f"❌ Token fetch failed for {api.name}", e)
        raise

def _refresh_token(api: APIConfig, session: Session) -> bool:
    """Refresh existing token"""
    if not api.auth or not api.auth.token_refresh_endpoint:
        return False

    token_info = session._auth_tokens.get(api.name, {})
    if not token_info.get("refresh_token"):
        return False

    log_info(f"🔄 Refreshing token for {api.name}")

    try:
        body = _render_json(api.auth.token_refresh_body or {}, session, api.name)
        body["refresh_token"] = token_info["refresh_token"]

        response = requests.post(
            str(api.auth.token_refresh_endpoint),
            json=body,
            timeout=api.timeout_seconds
        )
        response.raise_for_status()

        json_data = response.json()

        # Extract new token
        token = json_data
        for path_part in api.auth.response_token_path.split("."):
            token = token.get(path_part)
            if token is None:
                raise ValueError(f"Token path {api.auth.response_token_path} not found in refresh response")

        # Update session
        session._auth_tokens[api.name] = {
            "token": token,
            "expiry": time.time() + 3500,
            "refresh_token": json_data.get("refresh_token", token_info["refresh_token"])
        }

        log_info(f"✅ Token refreshed for {api.name}")
        return True

    except Exception as e:
        log_error(f"❌ Token refresh failed for {api.name}", e)
        return False

def _ensure_token(api: APIConfig, session: Session) -> None:
    """Ensure valid token exists for API"""
    if not api.auth or not api.auth.enabled:
        return

    token_info = session._auth_tokens.get(api.name)

    # No token yet
    if not token_info:
        _fetch_token(api, session)
        return

    # Token still valid
    if token_info.get("expiry", 0) > time.time():
        return

    # Try refresh first
    if _refresh_token(api, session):
        return

    # Refresh failed, get new token
    _fetch_token(api, session)

def call_api(api: APIConfig, session: Session) -> requests.Response:
    """Execute API call with automatic token management and better error handling"""

    # Ensure valid token
    _ensure_token(api, session)

    # Prepare request
    headers = _render(api.headers, session, api.name)
    body = _render_json(api.body_template, session, api.name)

    # Get timeout with fallback
    timeout = api.timeout_seconds if api.timeout_seconds else DEFAULT_TIMEOUT

    # Handle proxy
    proxies = None
    if api.proxy:
        if isinstance(api.proxy, str):
            proxies = {"http": api.proxy, "https": api.proxy}
        elif hasattr(api.proxy, "enabled") and api.proxy.enabled:
            proxy_url = str(api.proxy.url)
            proxies = {"http": proxy_url, "https": proxy_url}

    # Prepare request parameters
    request_params = {
        "method": api.method,
        "url": str(api.url),
        "headers": headers,
        "timeout": timeout,  # Use configured timeout
        "stream": True  # Enable streaming for large responses
    }

    # Add body based on method
    if api.method in ("POST", "PUT", "PATCH"):
        request_params["json"] = body
    elif api.method == "GET" and body:
        request_params["params"] = body

    if proxies:
        request_params["proxies"] = proxies

    # Execute with retry
    retry_count = api.retry.retry_count if api.retry else 0
    last_error = None
    response = None

    for attempt in range(retry_count + 1):
        try:
            # Use LogTimer for performance tracking
            with LogTimer(f"API call {api.name}", attempt=attempt + 1):
                log_info(
                    f"🌐 API call starting",
                    api=api.name,
                    method=api.method,
                    url=api.url,
                    attempt=f"{attempt + 1}/{retry_count + 1}",
                    timeout=timeout
                )

                if body:
                    log_debug(f"📋 Request body", body=json.dumps(body, ensure_ascii=False)[:500])

                # Make request with streaming
                response = requests.request(**request_params)

                # Check response size from headers
                content_length = response.headers.get('content-length')
                if content_length and int(content_length) > MAX_RESPONSE_SIZE:
                    response.close()
                    raise ValueError(f"Response too large: {int(content_length)} bytes (max: {MAX_RESPONSE_SIZE})")

                # Handle 401 Unauthorized
                if response.status_code == 401 and api.auth and api.auth.enabled and attempt < retry_count:
                    log_warning(f"🔒 Got 401, refreshing token", api=api.name)
                    _fetch_token(api, session)
                    headers = _render(api.headers, session, api.name)
                    request_params["headers"] = headers
                    response.close()
                    continue

                # Read response with size limit
                content_size = 0
                chunks = []

                for chunk in response.iter_content(chunk_size=8192):
                    chunks.append(chunk)
                    content_size += len(chunk)

                    if content_size > MAX_RESPONSE_SIZE:
                        response.close()
                        raise ValueError(f"Response exceeded size limit: {content_size} bytes")

                # Reconstruct response content
                response._content = b''.join(chunks)
                response._content_consumed = True

                # Check status
                response.raise_for_status()

                log_info(
                    f"✅ API call successful",
                    api=api.name,
                    status_code=response.status_code,
                    response_size=content_size,
                    duration_ms=f"{response.elapsed.total_seconds() * 1000:.2f}"
                )

                # Mevcut response mapping işlemi korunacak
                if response.status_code in (200, 201, 202, 204) and hasattr(api, 'response_mappings') and api.response_mappings:
                    try:
                        if response.status_code != 204 and response.content:
                            response_json = response.json()

                            for mapping in api.response_mappings:
                                var_name = mapping.get('variable_name')
                                var_type = mapping.get('type', 'str')
                                json_path = mapping.get('json_path')

                                if not all([var_name, json_path]):
                                    continue

                                # JSON path'ten değeri al
                                value = response_json
                                for path_part in json_path.split('.'):
                                    if isinstance(value, dict):
                                        value = value.get(path_part)
                                        if value is None:
                                            break

                                if value is not None:
                                    # Type conversion
                                    if var_type == 'int':
                                        value = int(value)
                                    elif var_type == 'float':
                                        value = float(value)
                                    elif var_type == 'bool':
                                        value = bool(value)
                                    elif var_type == 'date':
                                        value = str(value)
                                    else:  # str
                                        value = str(value)

                                    # Session'a kaydet
                                    session.variables[var_name] = value
                                    log_info(f"📝 Mapped response", variable=var_name, value=value)

                    except Exception as e:
                        log_error("⚠️ Response mapping error", error=str(e))

                return response

        except requests.exceptions.Timeout as e:
            last_error = e
            log_warning(
                f"⏱️ API timeout",
                api=api.name,
                attempt=attempt + 1,
                timeout=timeout
            )

        except requests.exceptions.RequestException as e:
            last_error = e
            log_error(
                f"❌ API request error",
                api=api.name,
                error=str(e),
                attempt=attempt + 1
            )

        except ValueError as e:  # Size limit exceeded
            log_error(
                f"❌ Response size error",
                api=api.name,
                error=str(e)
            )
            raise  # Don't retry for size errors

        except Exception as e:
            last_error = e
            log_error(
                f"❌ Unexpected API error",
                api=api.name,
                error=str(e),
                attempt=attempt + 1
            )

        # Retry backoff
        if attempt < retry_count:
            backoff = api.retry.backoff_seconds if api.retry else 2
            if api.retry and api.retry.strategy == "exponential":
                backoff = backoff * (2 ** attempt)
            log_info(f"⏳ Retry backoff", wait_seconds=backoff, next_attempt=attempt + 2)
            time.sleep(backoff)

    # All retries failed
    error_msg = f"API call failed after {retry_count + 1} attempts"
    log_error(error_msg, api=api.name, last_error=str(last_error))

    if last_error:
        raise last_error
    raise requests.exceptions.RequestException(error_msg)

def format_size(size_bytes: int) -> str:
    """Format bytes to human readable format"""
    for unit in ['B', 'KB', 'MB', 'GB']:
        if size_bytes < 1024.0:
            return f"{size_bytes:.2f} {unit}"
        size_bytes /= 1024.0
    return f"{size_bytes:.2f} TB"