import os
import rand
import term
import v.util.vtest
import v.util.diff

const vexe = @VEXE

const vroot = @VMODROOT

const diff_cmd = find_diff_cmd()

fn find_diff_cmd() string {
	return diff.find_working_diff_command() or { '' }
}

fn test_vet() ? {
	os.setenv('VCOLORS', 'never', true)
	os.chdir(vroot) ?
	test_dir := 'cmd/tools/vdoc/tests/testdata'
	main_files := get_main_files_in_dir(test_dir)
	fails := check_path(vexe, test_dir, main_files)
	assert fails == 0
}

fn get_main_files_in_dir(dir string) []string {
	mut mfiles := os.walk_ext(dir, '.v')
	mfiles.sort()
	return mfiles
}

fn check_path(vexe string, dir string, tests []string) int {
	mut nb_fail := 0
	paths := vtest.filter_vtest_only(tests, basepath: vroot)
	for path in paths {
		program := path
		print(path + ' ')
		res := os.execute('${os.quoted_path(vexe)} doc ${os.quoted_path(program)}')
		if res.exit_code < 0 {
			panic(res.output)
		}
		mut expected := os.read_file(program.replace('main.v', 'main.out')) or { panic(err) }
		expected = clean_line_endings(expected)
		found := clean_line_endings(res.output)
		if expected != found {
			print_compare(expected, found)
		}

		res_comments := os.execute('${os.quoted_path(vexe)} doc -comments ${os.quoted_path(program)}')
		if res_comments.exit_code < 0 {
			panic(res_comments.output)
		}
		mut expected_comments := os.read_file(program.replace('main.v', 'main.comments.out')) or {
			panic(err)
		}
		expected_comments = clean_line_endings(expected_comments)
		found_comments := clean_line_endings(res_comments.output)
		if expected_comments != found_comments {
			print_compare(expected_comments, found_comments)
		}

		if expected == found && expected_comments == found_comments {
			println(term.green('OK'))
		} else {
			nb_fail++
		}
	}
	return nb_fail
}

fn print_compare(expected string, found string) {
	println(term.red('FAIL'))
	println('============')
	println('expected:')
	println(expected)
	println('============')
	println('found:')
	println(found)
	println('============\n')
	println('diff:')
	println(diff.color_compare_strings(diff_cmd, rand.ulid(), found, expected))
	println('============\n')
}

fn clean_line_endings(s string) string {
	mut res := s.trim_space()
	res = res.replace(' \n', '\n')
	res = res.replace(' \r\n', '\n')
	res = res.replace('\r\n', '\n')
	res = res.trim('\n')
	return res
}