"""Positional coverage baseline v2: ranks are not detection recall.

Every declared target remains visible, including unmatched sites. No transitive detection
is inferred here: that requires recorded answered queries and target witnesses in the
push scorer. Historical v1 artifacts remain unchanged.
"""

from __future__ import annotations

import argparse
import hashlib
import json
import os
import subprocess
import sys
import time
from collections import Counter
from pathlib import Path

sys.path.insert(0, str(Path(__file__).resolve().parents[2] / "src"))

from openultrasast.mapping import analyze_entry_points  # noqa: E402
from openultrasast.model.regions import ScanRegion, regions_for  # noqa: E402
from openultrasast.model.shipped import declared_sources  # noqa: E402
from openultrasast.preprocess import preprocess_repository  # noqa: E402
from openultrasast.repos import checkout_path, load_repo_recipes  # noqa: E402

HEAD = 150  # how much of the evidence order a baseline records, region by region


def ordered_regions(root: Path) -> list[ScanRegion]:
    """The regions in the order `scan_repository` examines them. One definition, imported, never copied."""
    _, targets = preprocess_repository(root)
    regions = regions_for(analyze_entry_points(root, targets), targets, shipped=declared_sources(root))
    # The scan's own total order. If this drifts from scan.py the baseline measures the wrong thing, which
    # is why the sort key is the one thing here worth a test against the driver.
    from openultrasast.model.layout import with_layout

    return sorted(with_layout(regions), key=lambda r: (not r.shipped, -r.rank, r.path, r.function or ""))


def evidence_ordered_regions(root: Path, regions: list[ScanRegion], language: str) -> tuple[list[ScanRegion], dict[str, object]]:
    """The regions in the order phase 2 spends the budget: by each region's best (tier, score), from a real
    evidence pass over EVERY region. Needs Joern. The ordering function is the scan's own, imported."""
    import time

    from openultrasast.cpg.backend import resolve_cpg_backend
    from openultrasast.model.scan import _collect, _evidence_pass, _hook_callbacks, order_by_evidence

    # A benchmark pass runs over EVERY region, not the scan's 500: pmpro's 22,315 pairs took 255 s without
    # the join facts and past the scan's 300 s default with them, and a pass that times out answers
    # nothing -- which read as "tiers={}" once and cost a run. The scan's per-push ceiling is not this
    # measurement's; an operator who set one keeps it.
    os.environ.setdefault("OPENULTRASAST_CPG_QUERY_TIMEOUT", "1800")
    backend = resolve_cpg_backend()
    started = time.monotonic()
    # The RECIPE's language, never the first region's: WP Statistics's first region is JavaScript, and a
    # build asked for as JavaScript went looking for jssrc2cpg and lost the whole repository's measurement.
    from openultrasast.model.layout import vendored_directories

    cpg = backend.build(root, language=language, exclude=vendored_directories(root))
    build_seconds = round(time.monotonic() - started, 1)
    if cpg is None:
        raise SystemExit(f"no graph for {root}: {getattr(backend, 'last_failure', '')}")
    try:
        started = time.monotonic()
        evidence, failed = _evidence_pass(cpg, _collect(regions), _hook_callbacks(root, regions))
        evidence_seconds = round(time.monotonic() - started, 1)
    finally:
        if callable(getattr(cpg, "cleanup", None)):
            cpg.cleanup()
    tiers = Counter(e.tier for e in evidence.values())
    ordered = order_by_evidence(regions, evidence)
    best: dict[tuple[str, str], tuple[int, float]] = {}
    for (path, function, _family), vector in evidence.items():
        best[(path, function)] = max(best.get((path, function), (-1, 0.0)), vector.order_key)
    facts = {
        # The head of the order, with each region's (tier, score), so a baseline says WHAT sits ahead of a
        # pinned CVE and not only how much of it -- the within-tier ties are the next thing to read.
        "head": [
            {
                "position": i,
                "tier": best.get((r.path, r.function or ""), (-1, 0.0))[0],
                "score": best.get((r.path, r.function or ""), (-1, 0.0))[1],
                "site": f"{r.path}:{r.function or ''}",
                "rank": r.rank,
            }
            for i, r in enumerate(ordered[:HEAD])
        ],
        "build_seconds": build_seconds,
        "evidence_seconds": evidence_seconds,
        "pairs": len(evidence),
        "pairs_unanswered": failed,
        "tier_counts": {str(k): v for k, v in sorted(tiers.items())},
    }
    return ordered, facts


def measure(name: str, root: Path, known: list[dict[str, object]], *, by_evidence: bool = False, language: str = "") -> dict[str, object]:
    started = time.monotonic()
    inputs = []
    for path in sorted({str(item["file"]) for item in known}):
        try:
            content = (root / path).read_bytes()
            if not content:
                raise ValueError("empty source")
            inputs.append(dict(path=path, bytes_read=len(content), sha256=hashlib.sha256(content).hexdigest()))
        except (OSError, ValueError) as exc:
            inputs.append(dict(path=path, bytes_read=0, problem=str(exc)))
    facts: dict[str, object] = {}
    # Frozen identity recorded before the evidence pass; this is a rank-only experiment.
    source_root = Path(__file__).resolve().parents[2]
    version_paths = [
        "benchmarks/ranking/position.py",
        "src/openultrasast/model/regions.py",
        "src/openultrasast/model/scan.py",
        "src/openultrasast/model/evidence.py",
        "src/openultrasast/model/layout.py",
    ]
    checkout = {}
    try:
        commit = (
            subprocess.check_output(["git", "-C", str(root), "rev-parse", "HEAD"], stderr=subprocess.DEVNULL, timeout=10).decode().strip()
        )
        status = subprocess.check_output(["git", "-C", str(root), "status", "--porcelain"], stderr=subprocess.DEVNULL, timeout=10)
        checkout = dict(commit=commit, clean=not status, status_sha256=hashlib.sha256(status).hexdigest())
    except (OSError, subprocess.SubprocessError):
        checkout = dict(problem="checkout commit unavailable")
    profile = dict(
        checkout=checkout,
        version="position-v2",
        requested_ranking_mode="evidence" if by_evidence else "static",
        known_targets=known,
        input_witnesses=inputs,
        implementation={path: hashlib.sha256((source_root / path).read_bytes()).hexdigest() for path in version_paths},
        detection="not_measured",
    )
    profile["sha256"] = hashlib.sha256(json.dumps(profile, sort_keys=True).encode()).hexdigest()
    regions = ordered_regions(root) if root.is_dir() else []
    actual_mode = "static"
    if by_evidence:
        try:
            regions, facts = evidence_ordered_regions(root, regions, language)
            actual_mode = "evidence"
        except (OSError, RuntimeError, subprocess.SubprocessError, SystemExit) as exc:
            regions = []
            actual_mode = "unavailable"
            facts = dict(evidence_failure=str(exc))
    tiers = Counter(r.rank for r in regions)
    largest = max(tiers.values()) if tiers else 0
    rows: list[dict[str, object]] = []
    for item in known:
        # A known vulnerability names a file and a function. Match on both, path by suffix because a recipe
        # writes it relative to the repository and a region may carry it the same way or deeper.
        hit = next(
            (
                i
                for i, r in enumerate(regions)
                if r.path in (str(item["file"]), str(root / str(item["file"]))) and r.function == item["function"]
            ),
            None,
        )
        rows.append(
            {
                "id": item["id"],
                "family": item["family"],
                "site": f"{item['file']}:{item['line']}:{item['function']}",
                # Zero-based position is only a region match, never a completed detection.
                "position": hit,
                "rank": regions[hit].rank if hit is not None else None,
                "in_scope": item["in_scope"],
                "reached_transitively": False,
                "detection": "not_measured",
                "position_status": "matched" if hit is not None else "unresolved_target",
            }
        )
    positioned = [r["position"] for r in rows if r["position"] is not None and r["in_scope"]]
    supported = [row for row in rows if row["in_scope"]]
    all_located = bool(supported) and len(positioned) == len(supported)
    return {
        "schema_version": 2,
        "measurement": "positional_coverage_not_detection",
        "ranking_mode": actual_mode,
        "profile": profile,
        "detection_recall": None,
        "supported_population": len(supported),
        "unmatched_supported": len(supported) - len(positioned),
        "input_witnesses": inputs,
        "input_status": "readable" if inputs and all(row["bytes_read"] for row in inputs) else "incomplete",
        "total_seconds": round(time.monotonic() - started, 3),
        "repo": name,
        "regions": len(regions),
        "distinct_ranks": len(tiers),
        "largest_tier_share": round(largest / len(regions), 3) if regions else 0.0,
        "largest_tier_rank": max(tiers, key=lambda k: tiers[k]) if tiers else None,
        # The smallest examined-region budget that still holds every in-scope known vulnerability.
        "budget_at_recall": None,  # Retired misleading name: rank does not measure recall.
        "budget_at_full_target_position_coverage": (max(positioned) + 1)
        if all_located and all(row["bytes_read"] for row in inputs)
        else None,
        "known": rows,
        **facts,
    }


def main() -> int:
    parser = argparse.ArgumentParser(description=__doc__, formatter_class=argparse.RawDescriptionHelpFormatter)
    parser.add_argument("--json", action="store_true", help="emit one JSON object per repository")
    parser.add_argument("--repo", help="only this recipe")
    parser.add_argument("--evidence", action="store_true", help="phase 2: order by a real evidence pass over every region (needs Joern)")
    args = parser.parse_args()

    results: list[dict[str, object]] = []
    for recipe in load_repo_recipes():
        if args.repo and recipe.name != args.repo:
            continue
        if "detection" not in recipe.measures:
            continue
        root = checkout_path(recipe)
        if not root.is_dir():
            print(f"{recipe.name}: not checked out; retaining unresolved targets", file=sys.stderr)
        known = [
            {"id": k.id, "family": k.family, "file": k.file, "function": k.function, "line": k.line, "in_scope": k.in_scope}
            for k in recipe.known
        ]
        result = measure(recipe.name, root, known, by_evidence=args.evidence, language=recipe.language)
        results.append(result)
        # One line per repository as it lands, so a failure on the next repository cannot lose this one.
        print(json.dumps(result), file=sys.stderr, flush=True)

    if args.json:
        print(json.dumps(results, indent=2))
        return 1 if any(r["unmatched_supported"] or r["input_status"] != "readable" or r.get("evidence_failure") for r in results) else 0
    for r in results:
        print(
            f"{r['repo']}: {r['regions']} regions, {r['distinct_ranks']} distinct ranks, "
            f"{100 * float(r['largest_tier_share']):.1f}% share rank {r['largest_tier_rank']}"
        )
        for k in r["known"]:
            where = "unresolved target position" if k["position"] is None else f"position {k['position']} (rank {k['rank']})"
            scope = "" if k["in_scope"] else "  [out of scope]"
            print(f"   {k['id']:16} {where:28} {k['site']}{scope}")
        print(f"   budget_at_full_target_position_coverage = {r['budget_at_full_target_position_coverage']}; detection not measured")
        if "tier_counts" in r:
            print(f"   build {r['build_seconds']}s, evidence {r['evidence_seconds']}s over {r['pairs']} pairs, tiers {r['tier_counts']}")
    return 1 if any(r["unmatched_supported"] or r["input_status"] != "readable" or r.get("evidence_failure") for r in results) else 0


if __name__ == "__main__":
    raise SystemExit(main())