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# pylint: disable=invalid-name
# pylint: disable=protected-access

""" Test process.py """

import contextlib
import io
import unittest
from lldbtest.testcase import LLDBTestCase
from lldbmock.utils import lookup_type
from lldbmock.valuemock import ValueMock

import process as tst_process
import utils as tst_utils
from process import ShowTask, ShowProc, INVALID_PROC_SUMMARY, INVALID_TASK_SUMMARY

class ProcessTest(LLDBTestCase):
    """ Tests for process.py module """

    ROUNDED_UP_PROC_SIZE = 2048

    def test_GetProcPid(self):
        """ Test a pid gets returned. """

        proc = ValueMock.createFromType('proc')
        proc.p_pid = 12345

        self.assertEqual(tst_process.GetProcPID(proc), 12345)
        self.assertEqual(tst_process.GetProcPID(None), -1)

    def test_GetNameShort(self):
        """ Test fallback to short name. """

        proc = ValueMock.createFromType('proc')
        proc.p_name = ""
        proc.p_comm = "short-proc"

        self.assertEqual(tst_process.GetProcName(proc), "short-proc")

    def test_GetNameLong(self):
        """ Test that long name is preferred. """

        proc = ValueMock.createFromType('proc')
        proc.p_name = "long-proc"
        proc.p_comm = "short-proc"

        self.assertEqual(tst_process.GetProcName(proc), "long-proc")

    def test_GetNameInvalid(self):
        """ Test that invalid proc returns default name. """

        self.assertEqual(
            tst_process.GetProcName(None),
            tst_process.NO_PROC_NAME
        )

    def test_ASTValuesInSync(self):
        """ Test that thread states cover all values defined in kernel. """

        # Compare all values with AST chars dictionary.
        macro = tst_process._AST_CHARS.keys()

        # Add rest of values from the enum in kernel.
        enum = lookup_type('ast_t')
        self.assertTrue(enum.IsValid())

        kernel = [
            k.GetValueAsUnsigned()
            for k in enum.get_enum_members_array()
        ]

        # Assert that both sides handle identical set of flags.
        self.assertSetEqual(set(macro), set(kernel),
                            "thread state chars mismatch")

    def test_GetAstSummary(self):
        """ Test AST string genration. """

        ast = tst_utils.GetEnumValue('ast_t', 'AST_DTRACE')
        ast |= tst_utils.GetEnumValue('ast_t', 'AST_TELEMETRY_KERNEL')

        # Check valid AST
        self.assertEqual(tst_process.GetASTSummary(ast), 'TD')

        # Check that we never touch unsupported bits in an invalid value
        ast = 0xffffffff
        aststr = ''.join(char for _, char in tst_process._AST_CHARS.items())

        self.assertEqual(tst_process.GetASTSummary(ast), aststr)
    
    # Mock global variable value (accessed by the macro being used)
    @unittest.mock.patch('xnu.kern.globals.proc_struct_size', ROUNDED_UP_PROC_SIZE)
    def test_ProcWithoutTask(self):
        """ Test that ShowTask handles process-less task gracefully, and vice-versa for ShowProc """
        self.reset_mocks()

        PROC_ADDR = 0xffffffff90909090
        TASK_ADDR = PROC_ADDR + self.ROUNDED_UP_PROC_SIZE
        PROC_RO_ADDR = 0xffffff0040404040

        # Create fake proc_t instance at 0xffffffff90909090
        proc = self.create_mock('proc', PROC_ADDR).fromDict({
            'p_pid': 12345,
            'p_lflag': 0, # P_LHASTASK not set
            'p_comm': b'test-proc\0'
        })

        # Create task which is expected to be placed + sizeof(proc)
        task = self.create_mock('task', TASK_ADDR).fromDict({
            'effective_policy': {
                'tep_sup_active': 0,
                'tep_darwinbg': 0,
                'tep_lowpri_cpu': 1
            },
            't_flags': 0 # TF_HASPROC not set
        })

        # Created shared proc_ro reference from both task/proc
        self.create_mock('proc_ro', PROC_RO_ADDR)
        proc.p_proc_ro = PROC_RO_ADDR
        task.bsd_info_ro = PROC_RO_ADDR

        # Capture stdout and check expected output
        stdout = io.StringIO()
        with contextlib.redirect_stdout(stdout):
            ShowTask([f'{TASK_ADDR:#x}'])
            ShowProc([f'{PROC_ADDR:#x}'])

        self.assertIn(INVALID_PROC_SUMMARY, stdout.getvalue())
        self.assertIn(INVALID_TASK_SUMMARY, stdout.getvalue())