-- A command-line interface for the static analyzer explcheck.

local new_issues = require("explcheck-issues")
local format = require("explcheck-format")

local preprocessing = require("explcheck-preprocessing")
-- local lexical_analysis = require("explcheck-lexical-analysis")
-- local syntactic_analysis = require("explcheck-syntactic-analysis")
-- local semantic_analysis = require("explcheck-semantic-analysis")
-- local pseudo_flow_analysis = require("explcheck-pseudo-flow-analysis")

-- Deduplicate pathnames.
local function deduplicate_pathnames(pathnames)
  local deduplicated_pathnames = {}
  local seen_pathnames = {}
  for _, pathname in ipairs(pathnames) do
    if seen_pathnames[pathname] ~= nil then
      goto continue
    end
    seen_pathnames[pathname] = true
    table.insert(deduplicated_pathnames, pathname)
    ::continue::
  end
  return deduplicated_pathnames
end

-- Process all input files.
local function main(pathnames, warnings_are_errors, max_line_length)
  local num_warnings = 0
  local num_errors = 0

  print("Checking " .. #pathnames .. " files")

  for pathname_number, pathname in ipairs(pathnames) do

    -- Load an input file.
    local file = assert(io.open(pathname, "r"), "Could not open " .. pathname .. " for reading")
    local content = assert(file:read("*a"))
    assert(file:close())
    local issues = new_issues()

    -- Run all processing steps.
    local line_starting_byte_numbers, _ = preprocessing(issues, content, max_line_length)
    if #issues.errors > 0 then
      goto continue
    end
    -- lexical_analysis(issues)
    -- syntactic_analysis(issues)
    -- semantic_analysis(issues)
    -- pseudo_flow_analysis(issues)

    -- Print warnings and errors.
    ::continue::
    num_warnings = num_warnings + #issues.warnings
    num_errors = num_errors + #issues.errors
    format.print_results(pathname, issues, line_starting_byte_numbers, pathname_number == #pathnames)
  end

  -- Print a summary.
  format.print_summary(#pathnames, num_warnings, num_errors)

  if(num_errors > 0) then
    return 1
  elseif(warnings_are_errors and num_warnings > 0) then
    return 2
  else
    return 0
  end
end

local function print_usage()
  print("Usage: " .. arg[0] .. " [OPTIONS] FILENAMES\n")
  print("Run static analysis on expl3 files.\n")
  print("Options:")
  print("\t--max-line-length=N\tThe maximum line length before the warning S103 (Line too long) is produced.")
  print("\t--warnings-are-errors\tProduce a non-zero exit code if any warnings are produced by the analysis.")
end

local function print_version()
  print("explcheck (expltools 2024-12-09) v0.1.1")
  print("Copyright (c) 2024 Vít Starý Novotný")
  print("Licenses: LPPL 1.3 or later, GNU GPL v2 or later")
end

if #arg == 0 then
  print_usage()
  os.exit(1)
else
  -- Collect arguments.
  local pathnames = {}
  local warnings_are_errors = false
  local only_pathnames_from_now_on = false
  local max_line_length = nil
  for _, argument in ipairs(arg) do
    if only_pathnames_from_now_on then
      table.insert(pathnames, argument)
    elseif argument == "--" then
      only_pathnames_from_now_on = true
    elseif argument == "--help" or argument == "-h" then
      print_usage()
      os.exit(0)
    elseif argument == "--version" or argument == "-v" then
      print_version()
      os.exit(0)
    elseif argument == "--warnings-are-errors" then
      warnings_are_errors = true
    elseif argument:sub(1, 18) == "--max-line-length=" then
      max_line_length = tonumber(argument:sub(19))
    elseif argument:sub(1, 2) == "--" then
      -- An unknown argument
      print_usage()
      os.exit(1)
    else
      table.insert(pathnames, argument)
    end
  end
  pathnames = deduplicate_pathnames(pathnames)

  -- Run the analysis.
  local exit_code = main(pathnames, warnings_are_errors, max_line_length)
  os.exit(exit_code)
end