from app.core.monitoring.otel_logger import initialize_otel_logger

# Call once at app startup
initialize_otel_logger(
    log_level="INFO",
    enable_console=True,
    enable_otlp=True,
    otlp_endpoint="localhost:4317"
)

from app.core.monitoring.otel_logger import logger, get_tracer

# Module-level initialization
logger = logger(__name__)
tracer = get_tracer(__name__)

from app.core.monitoring.otel_logger import trace_span, logger

logger = logger(__name__)

# Logs automatically include trace_id and span_id
with trace_span("process_order", order_id="12345") as span:
    logger.info("processing_order", order_id="12345")
    # Do work...
    logger.info("order_processed", result_count=5)

# app/shared/otel_config.py
from opentelemetry import logs
from opentelemetry.sdk.logs import LoggerProvider
from opentelemetry.sdk.logs.export import ConsoleLogExporter, SimpleLogRecordExporter
from opentelemetry.sdk.resources import Resource

def setup_console_logging(service_name: str) -> LoggerProvider:
    """Set up OTEL logging with console exporter."""
    resource = Resource.create({"service.name": service_name})
    logger_provider = LoggerProvider(resource=resource)

    exporter = ConsoleLogExporter()
    processor = SimpleLogRecordExporter(exporter)
    logger_provider.add_log_record_processor(processor)
    logs.set_logger_provider(logger_provider)

    return logger_provider

# app/shared/logging_setup.py
import structlog
from opentelemetry.instrumentation.logging import LoggingInstrumentor

def setup_structlog() -> None:
    """Configure structlog with OTEL trace context integration."""
    # Enable OTEL logging instrumentation
    LoggingInstrumentor().instrument()

    # Configure structlog
    structlog.configure(
        processors=[
            structlog.contextvars.merge_contextvars,
            structlog.processors.TimeStamper(fmt="iso"),
            structlog.processors.ExceptionRenderer(),
            structlog.processors.JSONRenderer(),
        ],
        logger_factory=structlog.logging.LoggerFactory(),
        cache_logger_on_first_use=True,
    )

def get_logger(name: str):
    """Get a logger instance with trace context support."""
    return structlog.logger(name)

# app/shared/observability.py
from contextvars import ContextVar
from opentelemetry import trace

# Context variables for request tracking
request_id_var: ContextVar[str | None] = ContextVar("request_id", default=None)
user_id_var: ContextVar[str | None] = ContextVar("user_id", default=None)

class ObservabilityContext:
    """Manage observability context (trace IDs, request IDs, user IDs)."""

    @staticmethod
    def set_request_id(request_id: str) -> None:
        """Set request ID in context."""
        request_id_var.set(request_id)

    @staticmethod
    def get_tracer(name: str):
        """Get tracer instance."""
        return trace.get_tracer(name)

    @staticmethod
    def set_span_attribute(key: str, value: any) -> None:
        """Set attribute on current span."""
        span = trace.get_current_span()
        if span.is_recording():
            span.set_attribute(key, value)

# app/config.py
from pydantic import Field
from pydantic_settings import BaseSettings

class Config(BaseSettings):
    """Configuration for OTEL logging."""

    otel_enabled: bool = Field(default=True)
    otel_exporter_type: str = Field(default="console")  # 'otlp', 'jaeger', or 'console'
    otel_otlp_endpoint: str = Field(default="localhost:4317")
    otel_jaeger_host: str = Field(default="localhost")
    otel_jaeger_port: int = Field(default=6831)

# main.py
from app.config import Config
from app.shared.logging_setup import setup_structlog, get_logger
from app.shared.otel_config import OTELConfig

async def main() -> None:
    """Main entry point."""
    config = Config()
    setup_structlog()

    if config.otel_enabled:
        otel_config = OTELConfig(
            service_name="my-service",
            exporter_type=config.otel_exporter_type,
            otlp_endpoint=config.otel_otlp_endpoint,
        )
        otel_config.setup_logging()
        otel_config.setup_tracing()

    logger = get_logger(__name__)
    logger.info("service_started")

# app/use_cases/extract_orders.py
from opentelemetry import trace
from app.shared.logging_setup import get_logger

class ExtractOrdersUseCase:
    """Use case with observability."""

    def __init__(self, gateway, publisher) -> None:
        self.gateway = gateway
        self.publisher = publisher
        self.logger = get_logger(__name__)
        self.tracer = trace.get_tracer(__name__)

    async def execute(self) -> int:
        """Execute with tracing."""
        with self.tracer.start_as_current_span("extract_orders") as span:
            self.logger.info("starting_extraction")

            try:
                orders = await self.gateway.fetch_all_orders()
                self.logger.info("orders_fetched", count=len(orders))

                for order in orders:
                    await self.publisher.publish(order)

                span.set_attribute("orders_processed", len(orders))
                self.logger.info("extraction_completed", total=len(orders))
                return len(orders)

            except Exception as e:
                self.logger.error("extraction_failed", error=str(e))
                span.record_exception(e)
                raise

# app/error_handlers.py
from fastapi import FastAPI, Request
from fastapi.responses import JSONResponse
from app.shared.logging_setup import get_logger
from app.shared.observability import ObservabilityContext

logger = get_logger(__name__)

async def global_exception_handler(request: Request, exc: Exception) -> JSONResponse:
    """Global exception handler with OTEL logging."""
    request_id = ObservabilityContext.get_request_id()

    logger.error(
        "unhandled_exception",
        error=str(exc),
        error_type=type(exc).__name__,
        request_id=request_id,
        path=request.url.path,
        method=request.method,
        exc_info=True,  # Include full stack trace
    )

    return JSONResponse(
        status_code=500,
        content={"detail": "Internal server error", "request_id": request_id},
    )

def setup_error_handlers(app: FastAPI) -> None:
    """Register error handlers."""
    app.add_exception_handler(Exception, global_exception_handler)

from opentelemetry import trace
from app.shared.logging_setup import get_logger

logger = get_logger(__name__)
tracer = trace.get_tracer(__name__)

with tracer.start_as_current_span("process_payment"):
    logger.info("payment_started", customer_id="cust-123")
    logger.info("payment_completed", amount=99.99)
    # All logs have same trace_id and span_id

from app.shared.observability import ObservabilityContext

ObservabilityContext.set_request_id("req-12345")
ObservabilityContext.set_user_id("user-456")

logger.info("user_action", action="login")
# Log includes request_id and user_id automatically

import pytest
from opentelemetry import logs
from opentelemetry.sdk.logs import LoggerProvider

def test_logging_configuration():
    """Test OTEL logging provider setup."""
    logger_provider = LoggerProvider()
    assert logger_provider is not None
    logs.set_logger_provider(logger_provider)
    assert logs.get_logger_provider() == logger_provider

@pytest.fixture
def in_memory_log_exporter():
    """In-memory exporter for testing."""
    class InMemoryExporter:
        def __init__(self):
            self.records = []

        def emit(self, log_records):
            self.records.extend(log_records)

    return InMemoryExporter()

def test_trace_context_in_logs(in_memory_log_exporter):
    """Verify trace context is included in logs."""
    # Setup logger and tracer
    # Log within span
    # Verify trace context in exported logs
    pass