"""Tests for nova CLI subcommands (P1, CAP-033 + CAP-034, REQ-324).

CAP-033: `nova --help` lists a subcommand for every user-facing core/ module.
CAP-034: AST-scan every nova/<module>.py (except cli.py, __init__.py) for
         line count ≤50, ≤3 FunctionDef, calls resolve to core.* imports,
         and no `if` statements except `if __name__ == "__main__"`.
Also: `nova init` scaffolds .nova/ + .gitignore in a tmp dir.
"""

from __future__ import annotations

import ast
import os
import subprocess
import sys

import pytest

NOVA_DIR = os.path.join(os.path.dirname(__file__), "..", "nova")
NOVA_DIR = os.path.abspath(NOVA_DIR)

# Expected subcommand for every user-facing core/ module
# (skip internal-only: env, local_emulators, *_cli shims, init_scaffold,
#  mode_resolver, confidence_signal has its own nova subcommand).
EXPECTED_SUBCOMMANDS = {
    "contract_resolver": "resolve",
    "decommission_transform": "decommission",
    "env_transition": "env-transition",
    "environment_check": "env-check",
    "hitl_gates": "hitl",
    "onboarding": "onboard",
    "outbox_writer": "outbox",
    "output_publisher": "publish-outputs",
    "policy_engine": "policy",
    "regression_verify": "regression",
    "separation_of_duties": "sod",
    "submission_readiness": "readiness",
    "attestation_matrix": "attestation-matrix",
    "confidence_signal": "confidence",
    "init_scaffold": "init",
}

# Builtins / stdlib names allowed as bare Call targets (everything else
# must resolve to a name imported from core.*).
_BUILTIN_CALLS = {
    "print", "open", "len", "str", "int", "bool", "dict", "list", "tuple",
    "range", "isinstance", "getattr", "setattr", "hasattr", "sorted",
    "min", "max", "sum", "any", "all", "enumerate", "zip", "map", "filter",
    "format", "repr", "type", "abs", "round",
}


def _nova_help_cmd():
    """Return the command list to invoke `nova --help` (prefer installed entry)."""
    nova = os.path.join(os.path.dirname(sys.executable), "nova")
    if os.path.isfile(nova):
        return [nova, "--help"]
    return [sys.executable, "-m", "nova.cli", "--help"]


# --- CAP-033: help lists every expected subcommand ---

def test_help_lists_all_subcommands():
    cmd = _nova_help_cmd()
    proc = subprocess.run(cmd, capture_output=True, text=True, cwd=os.getcwd())
    assert proc.returncode == 0, f"nova --help failed: {proc.stderr}"
    help_text = proc.stdout
    for core_mod, subname in EXPECTED_SUBCOMMANDS.items():
        assert subname in help_text, (
            f"subcommand {subname!r} (for core/{core_mod}.py) not in nova --help output"
        )


# --- CAP-034: AST scan of nova/<module>.py ---

def _nova_modules():
    out = []
    for fn in sorted(os.listdir(NOVA_DIR)):
        if not fn.endswith(".py"):
            continue
        if fn in ("cli.py", "__init__.py"):
            continue
        out.append(os.path.join(NOVA_DIR, fn))
    return out


def _core_imported_names(tree):
    """Collect names imported from `core` or `core.*` modules."""
    names = set()
    for node in ast.walk(tree):
        if isinstance(node, ast.ImportFrom) and node.module and (
            node.module == "core" or node.module.startswith("core.")
        ):
            for alias in node.names:
                names.add(alias.asname or alias.name)
    return names


@pytest.mark.parametrize("modpath", _nova_modules())
def test_module_caps034_constraints(modpath):
    src = open(modpath, encoding="utf-8").read()
    lines = src.splitlines()
    # (a) ≤50 lines
    assert len(lines) <= 50, f"{modpath}: {len(lines)} lines > 50"
    tree = ast.parse(src, filename=modpath)
    # (b) ≤3 FunctionDef/AsyncFunctionDef
    func_defs = [
        n for n in ast.walk(tree)
        if isinstance(n, (ast.FunctionDef, ast.AsyncFunctionDef))
    ]
    assert len(func_defs) <= 3, f"{modpath}: {len(func_defs)} function defs > 3"
    local_func_names = {f.name for f in func_defs}
    # (c) every bare Call target resolves to a core.* import, a builtin,
    #     or a function defined in this module (local helper).
    core_names = _core_imported_names(tree)
    allowed = core_names | _BUILTIN_CALLS | local_func_names
    for node in ast.walk(tree):
        if isinstance(node, ast.Call):
            func = node.func
            if isinstance(func, ast.Name):
                assert func.id in allowed, (
                    f"{modpath}: call to {func.id!r} not from a core.* import, "
                    f"a builtin, or a local function def"
                )
            # ast.Attribute calls (method calls on locals/args) are allowed
        # (d) no `if` statements except `if __name__ == "__main__"`
        if isinstance(node, ast.If):
            test = node.test
            is_main_guard = (
                isinstance(test, ast.Compare)
                and isinstance(test.left, ast.Name)
                and test.left.id == "__name__"
            )
            assert is_main_guard, f"{modpath}: non-__main__ `if` statement"


# --- nova init scaffolding ---

def test_nova_init_scaffolds(tmp_path):
    cmd = _nova_help_cmd()
    # build an init command (replace --help with init)
    init_cmd = cmd[:-1] + ["init"]
    proc = subprocess.run(init_cmd, capture_output=True, text=True, cwd=str(tmp_path))
    assert proc.returncode == 0, f"nova init failed: {proc.stderr}"
    nova_dir = tmp_path / ".nova"
    attest_dir = nova_dir / "contract.yml.attestations"
    gitignore = tmp_path / ".gitignore"
    assert nova_dir.is_dir(), ".nova/ not created"
    assert attest_dir.is_dir(), ".nova/contract.yml.attestations/ not created"
    assert gitignore.is_file(), ".gitignore not created"
    content = gitignore.read_text()
    for line in (
        "~/.nova/credentials.json",
        ".nova/credentials.json",
        "*.pem",
        "*.key",
        ".env",
        ".env.*",
    ):
        assert line in content, f"{line!r} missing from .gitignore"


def test_nova_init_refuses_without_force(tmp_path):
    (tmp_path / ".nova").mkdir()
    cmd = _nova_help_cmd()
    init_cmd = cmd[:-1] + ["init"]
    proc = subprocess.run(init_cmd, capture_output=True, text=True, cwd=str(tmp_path))
    assert proc.returncode == 1, f"nova init should refuse existing dir: {proc.stdout}"