--[[

File l3build-aux.lua Copyright (C) 2018-2024 The LaTeX Project

It may be distributed and/or modified under the conditions of the
LaTeX Project Public License (LPPL), either version 1.3c of this
license or (at your option) any later version.  The latest version
of this license is in the file

   https://www.latex-project.org/lppl.txt

This file is part of the "l3build bundle" (The Work in LPPL)
and all files in that bundle must be distributed together.

-----------------------------------------------------------------------

The development version of the bundle can be found at

   https://github.com/latex3/l3build

for those people who are interested.

--]]

-- local safety guards and shortcuts

local match = string.match
local gsub  = string.gsub

local pairs = pairs
local print = print

local lookup = kpse.lookup

local os_time = os.time
local os_type = os.type

--
-- Auxiliary functions which are used by more than one main function
--

---Convert the given `epoch` to a number.
---@param epoch string
---@return number
---@see l3build.lua
---@usage private?
function normalise_epoch(epoch)
  assert(epoch, 'normalize_epoch argument must not be nil')
  -- If given as an ISO date, turn into an epoch number
  local y, m, d = match(epoch, "^(%d%d%d%d)-(%d%d)-(%d%d)$")
  if y then
    return os_time({
        year = y, month = m, day   = d,
        hour = 0, sec = 0, isdst = nil
      }) - os_time({
        year = 1970, month = 1, day = 1,
        hour = 0, sec = 0, isdst = nil
      })
  elseif match(epoch, "^%d+$") then
    return tonumber(epoch)
  else
    return 0
  end
end

---Returns the CLI command (ending with `os_concat`) to set the epoch
---when forcecheckepoch is true, a void string otherwise.
---Will be run while checking or typesetting
---@param epoch string
---@param force boolean
---@return string
---@see check, typesetting
---@usage private?
function set_epoch_cmd(epoch, force)
  return force and (
    os_setenv .. " SOURCE_DATE_EPOCH=" .. epoch
      .. os_concat ..
    os_setenv .. " SOURCE_DATE_EPOCH_TEX_PRIMITIVES=1"
      .. os_concat ..
    os_setenv .. " FORCE_SOURCE_DATE=1"
      .. os_concat
  ) or ""
end

---Returns the script name depending on the calling sequence.
---`l3build ...` -> full path of `l3build.lua` in the TDS
---When called via `texlua l3build.lua ...`, `l3build.lua` is resolved to either
---`./l3build.lua` or the full path of `l3build.lua` in the TDS.
---`texlua l3build.lua` -> `/Library/TeX/texbin/l3build.lua` or `./l3build.lua`
---@return string
local function get_script_name()
  if match(arg[0], "l3build$") or match(arg[0], "l3build%.lua$") then
    return lookup("l3build.lua")
  else
    return arg[0] -- Why no lookup here?
  end
end

-- Performs the task named target given modules in a bundle.
---A module is the path of a directory relative to the main one.
---Uses `run` to launch a command.
---@param modules table List of modules.
---@param target string
---@param opts table
---@return number 0 on proper termination, a non 0 error code otherwise.
---@see many places, including latex2e/build.lua
---@usage Public
function call(modules, target, opts)
  -- Turn the option table into a CLI option string
  opts = opts or options
  local cli_opts = ""
  for k,v in pairs(opts) do
    if k ~= "names" and k ~= "target" then -- Special cases, TODO enhance the design to remove the need for this comment
      local t = option_list[k] or {}
      local value = ""
      if t["type"] == "string" then
        value = value .. "=" .. v
      elseif t["type"] == "table" then
        for _,a in pairs(v) do
          if value == "" then
            value = "=" .. a -- Add the initial "=" here
          else
            value = value .. "," .. a
          end
        end
      end
      cli_opts = cli_opts .. " --" .. k .. value
    end
  end
  if opts.names then
    for _, name in pairs(opts.names) do
      cli_opts = cli_opts .. " " .. name
    end
  end
  local script_name = get_script_name()
  for _, module in ipairs(modules) do
    local text
    if module == "." and opts["config"] and #opts["config"]>0 then
      text = " and configuration \"" .. opts["config"][1] .. "\""
    else
      text = " for module \"" .. module .. "\""
    end
    print("Running l3build with target \"" .. target .. "\"" .. text )
    local error_level = run(
      module,
      "texlua " .. script_name .. " " .. target .. cli_opts
    )
    if error_level ~= 0 then
      return error_level
    end
  end
  return 0
end

---Unpack the given dependencies.
---A dependency is the path of a directory relative to the main one.
---@param deps table regular array of dependencies.
---@return number 0 on proper termination, a non 0 error code otherwise.
---@see stdmain, check, unpack, typesetting
---@usage Private?
function dep_install(deps)
  local error_level
  for _, dep in ipairs(deps) do
    print("Installing dependency: " .. dep)
    error_level = run(dep, "texlua " .. get_script_name() .. " unpack -q")
    if error_level ~= 0 then
      return error_level
    end
  end
  return 0
end

-- Construct a localtexmf including any tdsdirs
-- Needed for checking and typesetting, hence global
function localtexmf()
  local paths = ""
  for src,_ in pairs(tdsdirs) do
    paths = paths .. os_pathsep .. abspath(src) .. "//"
  end
  if texmfdir and texmfdir ~= "" and direxists(texmfdir) then
    paths = paths .. os_pathsep .. abspath(texmfdir) .. "//"
  end
  return paths
end

-- Run a command after setting up the environmental variables
function runcmd(cmd,dir,vars)
  dir = dir or "."
  dir = abspath(dir)
  vars = vars or {}
  -- Allow for local texmf files
  local env = ""
  if not match(checkformat,"^context$")  then
    env = os_setenv .. " TEXMFCNF=." .. os_pathsep .. os_concat
  end
  local envpaths = "." .. localtexmf() .. os_pathsep
    .. abspath(localdir) .. os_pathsep
    .. dir .. (typesetsearch and os_pathsep or "")
  -- Deal with spaces in paths
  if os_type == "windows" and match(envpaths," ") then
    envpaths = gsub(envpaths,'"','')
  end
  for _,var in pairs(vars) do
    if env ~= "" then
      env = env .. os_setenv .. " " .. var .. "=" .. envpaths .. os_concat
    else
      env = os_setenv .. " " .. var .. "=" .. envpaths
    end
  end
  return run(dir,set_epoch_cmd(epoch, forcedocepoch) .. env .. cmd)
end
