#!/usr/bin/env python3
from __future__ import annotations

import argparse
import json
from collections import Counter
from dataclasses import asdict
from datetime import datetime
from pathlib import Path

from inire.tests.example_scenarios import TRACE_PERFORMANCE_SCENARIO_RUNS, TRACE_SCENARIO_RUNS


def _trace_registry(include_performance_only: bool) -> tuple[tuple[str, object], ...]:
    if include_performance_only:
        return TRACE_SCENARIO_RUNS + TRACE_PERFORMANCE_SCENARIO_RUNS
    return TRACE_SCENARIO_RUNS


def _selected_runs(
    selected_scenarios: tuple[str, ...] | None,
    *,
    include_performance_only: bool,
) -> tuple[tuple[str, object], ...]:
    if selected_scenarios is None:
        default_registry = dict(TRACE_PERFORMANCE_SCENARIO_RUNS)
        return (("example_07_large_scale_routing_no_warm_start", default_registry["example_07_large_scale_routing_no_warm_start"]),)

    registry = dict(TRACE_SCENARIO_RUNS + TRACE_PERFORMANCE_SCENARIO_RUNS)
    allowed_standard = dict(_trace_registry(include_performance_only))
    runs = []
    for name in selected_scenarios:
        if name in allowed_standard:
            runs.append((name, allowed_standard[name]))
            continue
        if name in registry:
            runs.append((name, registry[name]))
            continue
        valid = ", ".join(sorted(registry))
        raise SystemExit(f"Unknown trace scenario: {name}. Valid scenarios: {valid}")
    return tuple(runs)


def _build_payload(
    selected_scenarios: tuple[str, ...] | None,
    *,
    include_performance_only: bool,
) -> dict[str, object]:
    scenarios = []
    for name, run in _selected_runs(selected_scenarios, include_performance_only=include_performance_only):
        result = run()
        scenarios.append(
            {
                "name": name,
                "summary": {
                    "total_results": len(result.results_by_net),
                    "valid_results": sum(1 for entry in result.results_by_net.values() if entry.is_valid),
                    "reached_targets": sum(1 for entry in result.results_by_net.values() if entry.reached_target),
                },
                "metrics": asdict(result.metrics),
                "frontier_trace": [asdict(entry) for entry in result.frontier_trace],
            }
        )
    return {
        "generated_at": datetime.now().astimezone().isoformat(timespec="seconds"),
        "generator": "scripts/record_frontier_trace.py",
        "scenarios": scenarios,
    }


def _render_markdown(payload: dict[str, object]) -> str:
    lines = [
        "# Frontier Trace",
        "",
        f"Generated at {payload['generated_at']} by `{payload['generator']}`.",
        "",
    ]

    for scenario in payload["scenarios"]:
        lines.extend(
            [
                f"## {scenario['name']}",
                "",
                f"Results: {scenario['summary']['valid_results']} valid / "
                f"{scenario['summary']['reached_targets']} reached / "
                f"{scenario['summary']['total_results']} total.",
                "",
                "| Net | Hotspots | Closed-Set | Hard Collision | Self Collision | Cost | Samples |",
                "| :-- | --: | --: | --: | --: | --: | --: |",
            ]
        )

        reason_counts: Counter[str] = Counter()
        hotspot_counts: Counter[tuple[str, int]] = Counter()
        for net_trace in scenario["frontier_trace"]:
            sample_count = len(net_trace["samples"])
            lines.append(
                "| "
                f"{net_trace['net_id']} | "
                f"{len(net_trace['hotspot_bounds'])} | "
                f"{net_trace['pruned_closed_set']} | "
                f"{net_trace['pruned_hard_collision']} | "
                f"{net_trace['pruned_self_collision']} | "
                f"{net_trace['pruned_cost']} | "
                f"{sample_count} |"
            )
            reason_counts["closed_set"] += net_trace["pruned_closed_set"]
            reason_counts["hard_collision"] += net_trace["pruned_hard_collision"]
            reason_counts["self_collision"] += net_trace["pruned_self_collision"]
            reason_counts["cost"] += net_trace["pruned_cost"]
            for sample in net_trace["samples"]:
                hotspot_counts[(net_trace["net_id"], sample["hotspot_index"])] += 1

        lines.extend(["", "Prune totals by reason:", ""])
        if reason_counts:
            for reason, count in reason_counts.most_common():
                lines.append(f"- `{reason}`: {count}")
        else:
            lines.append("- None")

        lines.extend(["", "Top traced hotspots by sample count:", ""])
        if hotspot_counts:
            for (net_id, hotspot_index), count in hotspot_counts.most_common(10):
                lines.append(f"- `{net_id}` hotspot `{hotspot_index}`: {count}")
        else:
            lines.append("- None")

        lines.extend(["", "Per-net sampled reason/move breakdown:", ""])
        if scenario["frontier_trace"]:
            for net_trace in scenario["frontier_trace"]:
                reason_move_counts: Counter[tuple[str, str]] = Counter()
                hotspot_sample_counts: Counter[int] = Counter()
                for sample in net_trace["samples"]:
                    reason_move_counts[(sample["reason"], sample["move_type"])] += 1
                    hotspot_sample_counts[sample["hotspot_index"]] += 1
                lines.append(f"- `{net_trace['net_id']}`")
                if reason_move_counts:
                    top_pairs = ", ".join(
                        f"`{reason}` x `{move}` = {count}"
                        for (reason, move), count in reason_move_counts.most_common(3)
                    )
                    lines.append(f"  sampled reasons: {top_pairs}")
                else:
                    lines.append("  sampled reasons: none")
                if hotspot_sample_counts:
                    top_hotspots = ", ".join(
                        f"`{hotspot}` = {count}" for hotspot, count in hotspot_sample_counts.most_common(3)
                    )
                    lines.append(f"  hotspot samples: {top_hotspots}")
                else:
                    lines.append("  hotspot samples: none")
        else:
            lines.append("- None")

        lines.append("")

    return "\n".join(lines)


def main() -> None:
    parser = argparse.ArgumentParser(description="Record frontier-trace artifacts for selected trace scenarios.")
    parser.add_argument(
        "--scenario",
        action="append",
        dest="scenarios",
        default=[],
        help="Optional trace scenario name to include. May be passed more than once.",
    )
    parser.add_argument(
        "--include-performance-only",
        action="store_true",
        help="Include performance-only trace scenarios when selecting from the standard registry.",
    )
    parser.add_argument(
        "--output-dir",
        type=Path,
        default=None,
        help="Directory to write frontier_trace.json and frontier_trace.md into. Defaults to <repo>/docs.",
    )
    args = parser.parse_args()

    repo_root = Path(__file__).resolve().parents[1]
    output_dir = repo_root / "docs" if args.output_dir is None else args.output_dir.resolve()
    output_dir.mkdir(exist_ok=True)

    selected = tuple(args.scenarios) if args.scenarios else None
    payload = _build_payload(selected, include_performance_only=args.include_performance_only)
    json_path = output_dir / "frontier_trace.json"
    markdown_path = output_dir / "frontier_trace.md"

    json_path.write_text(json.dumps(payload, indent=2, sort_keys=True) + "\n")
    markdown_path.write_text(_render_markdown(payload) + "\n")

    if json_path.is_relative_to(repo_root):
        print(f"Wrote {json_path.relative_to(repo_root)}")
    else:
        print(f"Wrote {json_path}")
    if markdown_path.is_relative_to(repo_root):
        print(f"Wrote {markdown_path.relative_to(repo_root)}")
    else:
        print(f"Wrote {markdown_path}")


if __name__ == "__main__":
    main()