"""The Prometheus text parser every scraper shares (steward/core/prometheus.py)."""
import math

from steward.core import prometheus

# Shaped like Fabled Archives' /metrics: HELP and TYPE lines, info and state
# gauges with several labels, counters, and an untyped stray.
ARCHIVES = """\
# HELP fabledarchives_build_info Build of the running server.
# TYPE fabledarchives_build_info gauge
fabledarchives_build_info{version="2026.10.11.1458",channel="dev",commit="c49b470"} 1
# TYPE fabledarchives_backup_target_state gauge
fabledarchives_backup_target_state{target="Steward",target_id="3",state="fresh"} 1
fabledarchives_backup_target_state{target="Steward",target_id="3",state="late"} 0
# TYPE fabledarchives_http_requests_total counter
fabledarchives_http_requests_total{route="GET /api/files",status="200"} 1027
fabledarchives_http_requests_total{route="GET /api/files",status="404"} 3
stray_metric 4.5
"""


def test_families_carry_their_declared_type():
    fams = prometheus.parse(ARCHIVES)
    assert fams["fabledarchives_build_info"].type == "gauge"
    assert fams["fabledarchives_build_info"].help == "Build of the running server."
    assert fams["fabledarchives_http_requests_total"].type == "counter"
    assert fams["stray_metric"].type == "untyped"
    assert list(fams) == [
        "fabledarchives_build_info",
        "fabledarchives_backup_target_state",
        "fabledarchives_http_requests_total",
        "stray_metric",
    ]


def test_labels_keep_their_order_and_values():
    state = prometheus.parse(ARCHIVES)["fabledarchives_backup_target_state"]
    assert [s.labels for s in state.samples] == [
        (("target", "Steward"), ("target_id", "3"), ("state", "fresh")),
        (("target", "Steward"), ("target_id", "3"), ("state", "late")),
    ]
    assert [s.value for s in state.samples] == [1.0, 0.0]
    reqs = prometheus.parse(ARCHIVES)["fabledarchives_http_requests_total"]
    assert reqs.samples[0].label_dict() == {"route": "GET /api/files", "status": "200"}


def test_escaped_label_values_and_separators_inside_quotes():
    text = 'm{a="say \\"hi\\"",b="back\\\\slash",c="two\\nlines",d="x,y}z"} 2\n'
    (sample,) = prometheus.parse(text)["m"].samples
    assert sample.label_dict() == {
        "a": 'say "hi"', "b": "back\\slash", "c": "two\nlines", "d": "x,y}z",
    }


def test_histogram_and_summary_samples_belong_to_their_family():
    text = """\
# TYPE req_seconds histogram
req_seconds_bucket{le="0.1"} 3
req_seconds_bucket{le="+Inf"} 5
req_seconds_sum 0.9
req_seconds_count 5
# TYPE rpc summary
rpc{quantile="0.5"} 0.2
rpc_sum 7
rpc_count 30
"""
    fams = prometheus.parse(text)
    assert set(fams) == {"req_seconds", "rpc"}
    assert [s.name for s in fams["req_seconds"].samples] == [
        "req_seconds_bucket", "req_seconds_bucket", "req_seconds_sum", "req_seconds_count",
    ]
    assert fams["req_seconds"].samples[1].label_dict() == {"le": "+Inf"}
    assert [s.name for s in fams["rpc"].samples] == ["rpc", "rpc_sum", "rpc_count"]


def test_an_openmetrics_counter_owns_its_total_sample():
    fams = prometheus.parse("# TYPE jobs counter\njobs_total 12\n")
    assert list(fams) == ["jobs"]
    assert fams["jobs"].type == "counter"
    assert fams["jobs"].samples[0].name == "jobs_total"


def test_special_values_and_timestamps():
    text = "a NaN\nb +Inf\nc -Inf\nd 1.5e3 1700000000000\n"
    fams = prometheus.parse(text)
    assert math.isnan(fams["a"].samples[0].value)
    assert fams["b"].samples[0].value == math.inf
    assert fams["c"].samples[0].value == -math.inf
    assert fams["d"].samples[0].value == 1500.0


def test_malformed_lines_are_skipped_not_fatal():
    text = """\
good 1
bad-name 2
unterminated{a="x 3
nolabelvalue{a=} 4
novalue
spaced{a="1"}5
# TYPE weird nonsense
weird 6
good_too{a="b"} 7
"""
    fams = prometheus.parse(text)
    assert set(fams) == {"good", "weird", "good_too"}
    assert fams["weird"].type == "untyped"
    assert fams["good_too"].samples[0].value == 7.0


def test_traefik_reads_through_the_shared_parser():
    from plugins.traefik.scraper import parse_prometheus

    out = parse_prometheus(
        'traefik_service_requests_total{service="web@docker",code="200"} 10\n'
    )
    key = frozenset({("service", "web@docker"), ("code", "200")})
    assert out == {"traefik_service_requests_total": {key: 10.0}}