"""Helper script for large-project decomposition Robot Framework tests.

Usage:
    python helper_large_project_decompose.py below-threshold
    python helper_large_project_decompose.py multi-level
    python helper_large_project_decompose.py closure
    python helper_large_project_decompose.py topo-sort
    python helper_large_project_decompose.py cycle-detect
    python helper_large_project_decompose.py config-validation
"""

from __future__ import annotations

import os
import sys
import tempfile
from pathlib import Path

# Ensure source tree is importable
_SRC = str(Path(__file__).resolve().parents[1] / "src")
if _SRC not in sys.path:
    sys.path.insert(0, _SRC)

from cleveragents.application.services.decomposition_graph import (  # noqa: E402
    DependencyClosureComputer,
)
from cleveragents.application.services.decomposition_models import (  # noqa: E402
    DecompositionConfig,
    DependencyEdge,
    DependencyGraph,
    DependencyType,
)
from cleveragents.application.services.decomposition_service import (  # noqa: E402
    DecompositionService,
)


def _make_files(tmpdir: str, count: int, levels: int = 1) -> list[str]:
    """Create *count* empty files spread across *levels* directories."""
    paths: list[str] = []
    for i in range(count):
        level = i % levels
        parts = [f"level{d}" for d in range(level + 1)]
        dirpath = os.path.join(tmpdir, *parts)
        os.makedirs(dirpath, exist_ok=True)
        fpath = os.path.join(dirpath, f"file_{i:05d}.py")
        with open(fpath, "w") as fh:
            fh.write("x" * 200)
        paths.append(fpath)
    return sorted(paths)


def cmd_below_threshold() -> None:
    """Verify decomposition is skipped below threshold."""
    tmpdir = tempfile.mkdtemp(prefix="decompose-")
    files = _make_files(tmpdir, 5, 1)
    svc = DecompositionService()
    result = svc.decompose(files, DecompositionConfig(min_files_per_subplan=10))
    assert result.metrics.get("skipped") == 1
    assert len(result.nodes) == 1
    print("decompose-below-threshold-ok")


def cmd_multi_level() -> None:
    """Verify multi-level decomposition produces multiple nodes."""
    tmpdir = tempfile.mkdtemp(prefix="decompose-")
    files = _make_files(tmpdir, 500, 5)
    svc = DecompositionService()
    result = svc.decompose(files, DecompositionConfig(max_files_per_subplan=100))
    assert len(result.nodes) > 1
    assert result.max_depth_reached >= 1
    print(f"decompose-multi-level-ok nodes={len(result.nodes)}")


def cmd_closure() -> None:
    """Verify transitive closure computation."""
    g = DependencyGraph()
    for n in ("A", "B", "C", "D"):
        g.add_node(n)
    g.add_edge(DependencyEdge("A", "B", DependencyType.IMPORT))
    g.add_edge(DependencyEdge("B", "C", DependencyType.IMPORT))
    g.add_edge(DependencyEdge("C", "D", DependencyType.IMPORT))

    computer = DependencyClosureComputer()
    closure = computer.compute_closure(g, ["A"])
    assert {"A", "B", "C", "D"} <= closure
    print(f"decompose-closure-ok size={len(closure)}")


def cmd_topo_sort() -> None:
    """Verify topological sort produces valid order."""
    g = DependencyGraph()
    for n in ("A", "B", "C", "D"):
        g.add_node(n)
    g.add_edge(DependencyEdge("A", "B", DependencyType.IMPORT))
    g.add_edge(DependencyEdge("A", "C", DependencyType.IMPORT))
    g.add_edge(DependencyEdge("B", "D", DependencyType.IMPORT))
    g.add_edge(DependencyEdge("C", "D", DependencyType.IMPORT))

    computer = DependencyClosureComputer()
    order = computer.topological_sort(g)
    assert order.index("A") < order.index("B")
    assert order.index("A") < order.index("C")
    assert order.index("B") < order.index("D")
    assert order.index("C") < order.index("D")
    print(f"decompose-topo-sort-ok order={order}")


def cmd_cycle_detect() -> None:
    """Verify cycle detection finds a cycle."""
    g = DependencyGraph()
    for n in ("A", "B", "C"):
        g.add_node(n)
    g.add_edge(DependencyEdge("A", "B", DependencyType.IMPORT))
    g.add_edge(DependencyEdge("B", "C", DependencyType.IMPORT))
    g.add_edge(DependencyEdge("C", "A", DependencyType.IMPORT))

    computer = DependencyClosureComputer()
    cycles = computer.detect_cycles(g)
    assert len(cycles) >= 1
    print(f"decompose-cycle-detect-ok cycles={len(cycles)}")


def cmd_config_validation() -> None:
    """Verify invalid config raises ValueError."""
    for bad_kwargs in (
        {"max_depth": 0},
        {"max_files_per_subplan": 0},
        {"max_tokens_per_subplan": 0},
        {"min_files_per_subplan": 0},
    ):
        try:
            DecompositionConfig(**bad_kwargs)  # type: ignore[arg-type]
            print(f"FAIL: {bad_kwargs} did not raise")
            sys.exit(1)
        except ValueError:
            pass

    # Valid config should work
    DecompositionConfig()
    print("decompose-config-ok")


def main() -> None:
    """Dispatch subcommand."""
    if len(sys.argv) < 2:
        print("Usage: helper_large_project_decompose.py <command>")
        sys.exit(1)

    cmd = sys.argv[1]
    dispatch = {
        "below-threshold": cmd_below_threshold,
        "multi-level": cmd_multi_level,
        "closure": cmd_closure,
        "topo-sort": cmd_topo_sort,
        "cycle-detect": cmd_cycle_detect,
        "config-validation": cmd_config_validation,
    }
    func = dispatch.get(cmd)
    if func is None:
        print(f"Unknown command: {cmd}")
        sys.exit(1)
    func()


if __name__ == "__main__":
    main()