# Extra fixtures used for wasm testing, including some that override the default pytest fixtures.
import os
import pathlib
import re
import subprocess
import time
from functools import partial

import pytest
from playwright.sync_api import Page


# Only include particular test files when testing wasm.
# This can be removed when all tests support wasm.
def pytest_ignore_collect(collection_path: pathlib.Path) -> bool:
    return collection_path.name not in [
        "test_add.py",
        "test_branch.py",
        "test_checkout.py",
        "test_clone.py",
        "test_commit.py",
        "test_config.py",
        "test_diff.py",
        "test_fetch.py",
        "test_fixtures.py",
        "test_git.py",
        "test_init.py",
        "test_log.py",
        "test_merge.py",
        "test_mv.py",
        "test_push.py",
        "test_rebase.py",
        "test_remote.py",
        "test_reset.py",
        "test_revlist.py",
        "test_revparse.py",
        "test_rm.py",
        "test_showref.py",
        "test_stash.py",
        "test_status.py",
        "test_tag.py",
    ]


@pytest.fixture(scope="session", autouse=True)
def run_web_server():
    with open("serve.log", "w") as f:
        cwd = pathlib.Path(__file__).parent.parent / "wasm/test"
        proc = subprocess.Popen(["npm", "run", "serve"], stdout=f, stderr=f, cwd=cwd)
        # Wait a bit until server ready to receive connections.
        time.sleep(1)
        yield
        proc.terminate()


@pytest.fixture(scope="function", autouse=True)
def load_page(page: Page):
    # Load web page at start of every test.
    page.goto("http://localhost:8000")
    page.locator("#loaded").wait_for()


class MockPath(pathlib.Path):
    def __init__(self, path: str = ""):
        super().__init__(path)

    def exists(self) -> bool:
        p = subprocess.run(["stat", str(self)])
        return p.returncode == 0

    def is_dir(self) -> bool:
        p = subprocess.run(["stat", "-c", "%F", str(self)], capture_output=True, text=True)
        return p.returncode == 0 and p.stdout.strip() == "directory"

    def is_file(self) -> bool:
        p = subprocess.run(["stat", "-c", "%F", str(self)], capture_output=True, text=True)
        return p.returncode == 0 and p.stdout.strip() == "regular file"

    def iterdir(self):
        p = subprocess.run(
            ["ls", str(self), "-a", "-1"], capture_output=True, text=True, check=True
        )
        for f in filter(lambda f: f not in ["", ".", ".."], re.split(r"\r?\n", p.stdout)):
            yield MockPath(self / f)

    def mkdir(self, *, parents=False):
        args = [str(self)]
        if parents:
            args.append("-p")
        subprocess.run(["mkdir"] + args, capture_output=True, text=True, check=True)

    def read_bytes(self) -> bytes:
        raise RuntimeError("Not implemented")

    def read_text(self) -> str:
        p = subprocess.run(["cat", str(self)], capture_output=True, text=True, check=True)
        text = p.stdout
        text = text.removesuffix("\n")
        return text

    def write_bytes(self, data: bytes):
        # Convert binary data to a string where each element is backslash-escaped so that we can
        # write to file in cockle using `echo -e <backslash-escaped data>`.
        encoded_string = "".join(f"\\x{d:02x}" for d in data)
        cmd = ["echo", "-e", encoded_string, ">", str(self)]
        subprocess.run(cmd, capture_output=True, text=True, check=True)
        return len(data)

    def write_text(self, data: str):
        # Note that in general it is not valid to direct output of a subprocess.run call to a file,
        # but we get away with it here as the command arguments are passed straight through to
        # cockle without being checked.
        data = data.removesuffix("\n")
        cmd = ["echo", data, ">", str(self)]
        subprocess.run(cmd, capture_output=True, text=True, check=True)
        return len(data)

    def __truediv__(self, other):
        if isinstance(other, str):
            return MockPath(f"{self}/{other}")
        raise RuntimeError("MockPath.__truediv__ only supports strings")


def os_chdir(dir: str):
    subprocess.run(["cd", str(dir)], capture_output=True, check=True, text=True)


def os_getcwd():
    return subprocess.run(["pwd"], capture_output=True, check=True, text=True).stdout.strip()


def os_remove(file: str):
    return subprocess.run(["rm", str(file)], capture_output=True, check=True, text=True)


def os_rename(src: str | MockPath, dst: str | MockPath):
    return subprocess.run(["mv", str(src), str(dst)], capture_output=True, check=True, text=True)


def os_symlink(src: str | MockPath, dst: str | MockPath):
    return subprocess.run(
        ["ln", "-s", str(src), str(dst)], capture_output=True, check=True, text=True
    )


def subprocess_run(
    page: Page,
    cmd: list[str],
    *,
    capture_output: bool = False,
    check: bool = False,
    cwd: str | MockPath | None = None,
    input: str | None = None,
    text: bool | None = None,
) -> subprocess.CompletedProcess:
    shell_run = "async obj => await window.cockle.shellRun(obj.cmd, obj.input)"

    # Set cwd.
    if cwd is not None:
        proc = page.evaluate(shell_run, {"cmd": "pwd"})
        if proc["returncode"] != 0:
            raise RuntimeError("Error getting pwd")
        old_cwd = proc["stdout"].strip()
        if old_cwd == str(cwd):
            # cwd is already correct.
            cwd = None
        else:
            proc = page.evaluate(shell_run, {"cmd": f"cd {cwd}"})
            if proc["returncode"] != 0:
                raise RuntimeError(f"Error setting cwd to {cwd}")

    def maybe_wrap_arg(s: str | MockPath) -> str:
        # An argument containing whitespace (including newlines) needs to be wrapped in quotes if
        # it is not already, due to how the command is passed to cockle as a single string.
        # Could do better here.
        s = str(s)
        if re.search(r"\s", s) and not s.endswith("'"):
            return "'" + s + "'"
        return s

    shell_run_args = {"cmd": " ".join([maybe_wrap_arg(s) for s in cmd]), "input": input}
    proc = page.evaluate(shell_run, shell_run_args)

    # TypeScript object is auto converted to Python dict.
    # Want to return subprocess.CompletedProcess, consider namedtuple if this fails in future.
    returncode = proc["returncode"]
    stdout = proc["stdout"] if capture_output else ""
    stderr = proc["stderr"] if capture_output else ""
    if not text:
        stdout = stdout.encode("utf-8")
        stderr = stderr.encode("utf-8")

    # Reset cwd.
    if cwd is not None:
        proc = page.evaluate(shell_run, {"cmd": "cd " + old_cwd})
        if proc["returncode"] != 0:
            raise RuntimeError(f"Error setting cwd to {old_cwd}")

    if check and returncode != 0:
        raise subprocess.CalledProcessError(returncode, cmd, stdout, stderr)

    return subprocess.CompletedProcess(
        args=cmd, returncode=returncode, stdout=stdout, stderr=stderr
    )


@pytest.fixture(scope="function")
def tmp_path() -> MockPath:
    # Assumes only one tmp_path needed per test.
    path = MockPath("/drive/tmp0")
    subprocess.run(["mkdir", str(path)], check=True)
    assert path.exists()
    assert path.is_dir()
    return path


@pytest.fixture(scope="function", autouse=True)
def mock_subprocess_run(page: Page, monkeypatch):
    monkeypatch.setattr(subprocess, "run", partial(subprocess_run, page))
    monkeypatch.setattr(os, "chdir", os_chdir)
    monkeypatch.setattr(os, "getcwd", os_getcwd)
    monkeypatch.setattr(os, "remove", os_remove)
    monkeypatch.setattr(os, "rename", os_rename)
    monkeypatch.setattr(os, "symlink", os_symlink)