local async = require('gitsigns.async')
local log = require('gitsigns.debug.log')

local system = require('gitsigns.system').system

--- @type fun(cmd: string[], opts?: vim.SystemOpts): vim.SystemCompleted
local asystem = async.wrap(3, system)

--- @class Gitsigns.Git.JobSpec : vim.SystemOpts
--- @field ignore_error? boolean

--- @async
--- @param args string[]
--- @param spec? Gitsigns.Git.JobSpec
--- @return string[] stdout, string? stderr
local function git_command(args, spec)
  spec = spec or {}

  local cmd = {
    'git',
    '--no-pager',
    '--no-optional-locks',
    '--literal-pathspecs',
    '-c',
    'gc.auto=0', -- Disable auto-packing which emits messages to stderr
    unpack(args),
  }

  if spec.text == nil then
    spec.text = true
  end

  -- Fix #895. Only needed for Nvim 0.9 and older
  spec.clear_env = true

  --- @type vim.SystemCompleted
  local obj = asystem(cmd, spec)

  if not spec.ignore_error and obj.code > 0 then
    log.eprintf(
      "Received exit code %d when running command\n'%s':\n%s",
      obj.code,
      table.concat(cmd, ' '),
      obj.stderr
    )
  end

  local stdout_lines = vim.split(obj.stdout or '', '\n')

  if spec.text then
    -- If stdout ends with a newline, then remove the final empty string after
    -- the split
    if stdout_lines[#stdout_lines] == '' then
      stdout_lines[#stdout_lines] = nil
    end
  end

  if log.verbose then
    log.vprintf('%d lines:', #stdout_lines)
    for i = 1, math.min(10, #stdout_lines) do
      log.vprintf('\t%s', stdout_lines[i])
    end
  end

  if obj.stderr == '' then
    obj.stderr = nil
  end

  return stdout_lines, obj.stderr
end

return git_command