# Copyright 2026 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

from dataclasses import dataclass
from typing import List
import sys
import tempfile
import time
import subprocess

import setup_modules  # pylint: disable=unused-import

from chromium_src.tools.metrics.python_support.tests_helpers import (
  TestableScript,
)


@dataclass(frozen=True)
class FailedScriptResult:
  command: str
  status_code: int
  stdout: str
  stderr: str

  def error_message(self) -> str:
    return f"""
################################################################################
### Failed to run {self.command} (code: {self.status_code})
################################################################################
--------------------------------------------------------------------------------
--- stdout ({self.command})
--------------------------------------------------------------------------------
{self.stdout}
--------------------------------------------------------------------------------
--- stderr ({self.command})
--------------------------------------------------------------------------------
{self.stderr}
################################################################################
    """


def check_scripts(
  commands_to_check: List[TestableScript],
  cwd: str,
  display_progressbar: bool = True,
) -> List[FailedScriptResult]:
  """Checks if the provided python scripts finish successfully.

  Args:
    commands_to_check - a list of TestableScript to be executed.
    cwd - working directory to run the script in.
    display_progressbar - if True, the progressbar will be printed to stdout.

  Returns:
    A list of FailedScriptResult containing info about the commands that failed.
  """
  running_processes = []
  failed_commands = []
  total_commands = len(commands_to_check)
  completed_count = 0
  last_completed_count = -1

  for testable_script in commands_to_check:
    cmd_debug_str = ' '.join(testable_script.cmd)
    print(f'Running: {cmd_debug_str}')

    out_f = tempfile.TemporaryFile(
      mode='w+', encoding='utf-8', errors='replace'
    )
    err_f = tempfile.TemporaryFile(
      mode='w+', encoding='utf-8', errors='replace'
    )

    proc = subprocess.Popen(
      testable_script.cmd,
      stdout=out_f,
      stderr=err_f,
      shell=sys.platform == 'win32',
      cwd=cwd,
    )
    running_processes.append((testable_script, proc, out_f, err_f))

  while running_processes:
    # Iterating backwards to safely remove items from list
    for i in range(len(running_processes) - 1, -1, -1):
      testable_script, proc, out_f, err_f = running_processes[i]

      exit_code = proc.poll()

      if exit_code is not None:
        if exit_code != 0:
          out_f.seek(0)
          err_f.seek(0)

          failed_commands.append(
            FailedScriptResult(
              command=testable_script.identifiable_name,
              status_code=exit_code,
              stdout=out_f.read(),
              stderr=err_f.read(),
            )
          )

        out_f.close()
        err_f.close()

        completed_count += 1
        del running_processes[i]

    if display_progressbar and completed_count != last_completed_count:
      _print_progress_bar(completed_count, total_commands)
    last_completed_count = completed_count

    if running_processes:
      time.sleep(0.5)

  return failed_commands


def _print_progress_bar(iteration, total, length=40):
  """Helper to print a progress bar to stdout using standard libraries."""
  if total == 0:
    return

  percent = ('{0:.1f}').format(100 * (iteration / float(total)))
  filled_length = int(length * iteration // total)
  bar = '█' * filled_length + '-' * (length - filled_length)

  sys.stdout.write(
    f'\rWaiting for the scripts to finish: |{bar}| {percent}% Complete'
  )
  sys.stdout.flush()