import re
import sys
import logging

import requests
import pydantic
from opentelemetry import trace
from opentelemetry.sdk.resources import Resource
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.exporter.otlp.proto.grpc.trace_exporter import OTLPSpanExporter

logger = logging.getLogger("opentelemetry-export")

logging.basicConfig(level=logging.INFO)


class JobMetadata(pydantic.BaseModel, extra="ignore"):
    status: str
    duration: str
    name: str


class RunMetadata(pydantic.BaseModel, extra="ignore"):
    jobs: list[JobMetadata]
    status: str


def configure_tracer(*, endpoint: str, service_name: str):
    resource = Resource(
        attributes={
            "service.name": service_name,
        }
    )

    tracer_provider = TracerProvider(resource=resource)
    trace.set_tracer_provider(tracer_provider)
    span_processor = BatchSpanProcessor(OTLPSpanExporter(endpoint=endpoint))
    tracer_provider.add_span_processor(span_processor)


def parse_duration_string_as_seconds(duration: str) -> int:
    """
    Time is represented as "_h_m_s" strings where each blank is a numerical value. This
    converts those string values to seconds count.
    """

    pattern = re.compile(r"((?P<hours>\d+)h)?((?P<minutes>\d+)m)?((?P<seconds>\d+)s)?")

    matches = pattern.search(duration)

    total = 0

    total += int(matches.group("seconds")) if matches.group("seconds") else 0
    total += int(matches.group("minutes")) * 60 if matches.group("minutes") else 0
    total += int(matches.group("hours")) * 60 * 60 if matches.group("hours") else 0

    return total


def get_job_details(
    *, base_url: str, repo: str, token: str, run_id: int
) -> RunMetadata:
    """
    Fetches the given Forgejo Action run metadata.

    Because the Actions API is not documented or properly exposed, it is used 'as the browser would',
    which implies that we have to preface our data fetch with a page fetch to get a session cookie
    matching the authentication token. This also generates the CSRF token needed since the Actions
    job API uses POSTs for data fetches.
    """

    common_headers = {"Authorization": f"token {token}"}
    with requests.Session() as session:
        session.get(f"{base_url}/{repo}", headers=common_headers)
        run_response = session.post(
            f"{base_url}/{repo}/actions/runs/{run_id}/",
            headers={
                **common_headers,
                "x-csrf-token": session.cookies.get_dict()["_csrf"],
            },
        )

    return RunMetadata(**run_response.json()["state"]["run"])


# FIXME: Adjust span durations based on event + API data.
def create_span_from_run_metadata(run: RunMetadata):
    tracer = trace.get_tracer(__name__)

    with tracer.start_as_current_span("run") as run_span:
        run_span.set_attribute("status", run.status)
        for job in run.jobs:
            with tracer.start_as_current_span(job.name) as job_span:
                duration = parse_duration_string_as_seconds(job.duration)
                job_span.set_attributes(
                    {
                        "name": job.name,
                        "status": job.status,
                        "duration": duration,
                    }
                )


def run():
    otlp_service_name, otlp_endpoint, token, base_url, repo, run_id = sys.argv[1:7]

    logger.info(f"Configuring tracer, target is {otlp_endpoint}")

    configure_tracer(endpoint=otlp_endpoint, service_name=otlp_service_name)

    logger.info(f"Getting run metadata for run #{run_id} on {repo} ({base_url}/{repo})")

    metadata = get_job_details(
        token=token,
        base_url=base_url,
        repo=repo,
        run_id=run_id,
    )

    create_span_from_run_metadata(metadata)

    logger.info("Pushed trace to target!")


if __name__ == "__main__":
    run()