"""Shared paths, constants and TAP helpers for the dark_companions study."""
import os
import ssl
import time
import urllib.parse
import urllib.request

STUDY = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
DATA = os.path.join(STUDY, "data")
FIGS = os.path.join(STUDY, "figures")
RAW = os.environ.get("DARKCOMP_RAW", "fermi_raw/dark_companions")
for _d in (DATA, FIGS, RAW):
    os.makedirs(_d, exist_ok=True)

GAIA_TAP = "https://gea.esac.esa.int/tap-server/tap"
VIZIER_TAP = "https://tapvizier.cds.unistra.fr/TAPVizieR/tap"

# physical constants (SI)
H_PLANCK = 6.62607015e-34
C_LIGHT = 2.99792458e8
K_B = 1.380649e-23
SIGMA_SB = 5.670374419e-8
L_SUN = 3.828e26
AU = 1.495978707e11
PC = 3.0856775814913673e16
G_NEWT = 6.67430e-11
M_SUN = 1.98847e30
KAPPA_MAS = 8.144  # mas / Msun, Einstein-radius constant


def _ctx():
    return ssl.create_default_context()


def http_get(url, timeout=300):
    req = urllib.request.Request(url, headers={"User-Agent": "fermi-dark-companions/1.0"})
    with urllib.request.urlopen(req, timeout=timeout, context=_ctx()) as r:
        return r.read()


def tap_sync(base, adql, fmt="csv", timeout=600):
    data = urllib.parse.urlencode(
        {"REQUEST": "doQuery", "LANG": "ADQL", "FORMAT": fmt, "QUERY": adql}
    ).encode()
    req = urllib.request.Request(base + "/sync", data=data,
                                 headers={"User-Agent": "fermi-dark-companions/1.0"})
    with urllib.request.urlopen(req, timeout=timeout, context=_ctx()) as r:
        return r.read()


def tap_async(base, adql, fmt="csv", poll=5, timeout=3600, verbose=True):
    """Run an asynchronous TAP job and return the result bytes."""
    data = urllib.parse.urlencode(
        {"REQUEST": "doQuery", "LANG": "ADQL", "FORMAT": fmt, "PHASE": "RUN", "QUERY": adql}
    ).encode()
    req = urllib.request.Request(base + "/async", data=data,
                                 headers={"User-Agent": "fermi-dark-companions/1.0"})
    with urllib.request.urlopen(req, timeout=120, context=_ctx()) as r:
        job_url = r.geturl()
    t0 = time.time()
    while True:
        phase = http_get(job_url + "/phase", timeout=60).decode().strip()
        if verbose:
            print("   job", job_url.rsplit("/", 1)[-1], phase, f"{time.time()-t0:.0f}s", flush=True)
        if phase == "COMPLETED":
            break
        if phase in ("ERROR", "ABORTED"):
            err = http_get(job_url + "/error", timeout=60).decode(errors="replace")
            raise RuntimeError("TAP job failed: " + err[:2000])
        if time.time() - t0 > timeout:
            raise RuntimeError("TAP job timed out")
        time.sleep(poll)
    return http_get(job_url + "/results/result", timeout=1800)


def fetch_to(path, getter, force=False):
    """Download once; reuse the cached raw file afterwards."""
    if os.path.exists(path) and os.path.getsize(path) > 0 and not force:
        return path
    blob = getter()
    with open(path + ".part", "wb") as f:
        f.write(blob)
    os.replace(path + ".part", path)
    return path