"""Diagnostic: submit the minimal request via datapi directly and capture the
EXACT ECDS job document (the 'rejected' reason the cdsapi wrapper hides), plus
the dataset constraints (valid request space). Read-only diagnosis; no download.
"""
import json
import os
import time

import datapi

ROOT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
ECDS_URL = "https://ecds.ecmwf.int/api"
DATASET = "s2s-reforecasts"
req = json.load(open(os.path.join(ROOT, "config", "ecds_minimal_request.json")))
req.pop("_comment", None)

def _get_key():
    k = os.environ.get("CDSAPI_KEY")
    if k:
        return k
    rc = os.environ.get("CDSAPI_RC", os.path.expanduser("~/.cdsapirc"))
    if os.path.exists(rc):
        for line in open(rc):
            if line.strip().startswith("key"):
                return line.split(":", 1)[1].strip()
    return None


out = {"request": req}
c = datapi.ApiClient(url=ECDS_URL, key=_get_key())

# 1) constraints given the fixed selectors (reveals valid values)
try:
    proc = c.get_process(DATASET)
    con = proc.apply_constraints({
        "origin": "ecmwf",
        "forecast_type": "control_forecast",
        "level_type": "single_level",
    })
    out["constraints_keys"] = sorted(con.keys()) if isinstance(con, dict) else str(type(con))
    out["constraints_sample"] = {k: (con[k][:12] if isinstance(con[k], list) else con[k])
                                 for k in list(con)[:20]} if isinstance(con, dict) else None
except Exception as e:
    out["constraints_error"] = f"{type(e).__name__}: {e}"

# 2) submit and capture the raw job document on the terminal state
try:
    remote = c.submit(DATASET, req)
    out["request_id"] = remote.request_id
    print("submitted", remote.request_id, flush=True)
    term = {"successful", "failed", "rejected", "dismissed", "deleted"}
    st = None
    for _ in range(120):
        st = remote.status
        if st in term:
            break
        time.sleep(5)
    out["final_status"] = st
    try:
        out["job_json"] = remote.json
    except Exception as e:
        out["job_json_error"] = f"{type(e).__name__}: {e}"
except Exception as e:
    out["submit_error"] = f"{type(e).__name__}: {e}"

with open(os.path.join(ROOT, "metadata", "ecds_diagnostic.json"), "w") as f:
    json.dump(out, f, indent=2, default=str)
print(json.dumps({k: out.get(k) for k in
                  ("final_status", "constraints_keys", "constraints_error", "submit_error")},
                 indent=2, default=str), flush=True)
print("\n=== job_json ===", flush=True)
print(json.dumps(out.get("job_json", out.get("job_json_error")), indent=2, default=str)[:3000], flush=True)