import os

const string_int_vexe = @VEXE
const string_int_tests_dir = os.dir(@FILE)
const string_int_v3_dir = os.dir(string_int_tests_dir)
const string_int_vlib_dir = os.dir(string_int_v3_dir)
const string_int_v3_src = os.join_path(string_int_v3_dir, 'v3.v')

fn string_int_build_v3() string {
    v3_bin := os.join_path(os.temp_dir(), 'v3_string_int_markused_test_${os.getpid()}')
    os.rm(v3_bin) or {}
    build :=
        os.execute('${string_int_vexe} -gc none -path "${string_int_vlib_dir}|@vlib|@vmodules" -o ${v3_bin} ${string_int_v3_src}')
    assert build.exit_code == 0, build.output
    return v3_bin
}

fn test_top_level_string_int_roots_exact_receiver_method() {
    v3_bin := string_int_build_v3()
    src := os.join_path(os.temp_dir(), 'v3_string_int_markused_${os.getpid()}.v')
    os.write_file(src, "module main

struct S {
    value int
}

struct U {
    value int
}

fn (s S) int() int {
    return s.value + 1
}

fn (u U) int() int {
    return u.value + 100
}

fn use_local_receiver() {
    s := S{
        value: 41
    }
    println(s.int())
}

println('42'.int())
use_local_receiver()
") or {
        panic(err)
    }
    bin := os.join_path(os.temp_dir(), 'v3_string_int_markused_${os.getpid()}')
    compile := os.execute('${v3_bin} ${src} -b c -o ${bin}')
    assert compile.exit_code == 0, compile.output
    assert !compile.output.contains('implicit declaration'), compile.output
    run := os.execute(bin)
    assert run.exit_code == 0, run.output
    assert run.output.trim_space() == '42\n42', run.output

    generated := os.read_file(bin + '.c') or { panic(err) }
    string_int_refs := generated.count('string__int(')
    assert string_int_refs >= 2, generated
    assert generated.contains('S__int('), generated
    assert !generated.contains('U__int('), generated
}

fn test_top_level_or_block_root_receiver_call_roots_string_int() {
    v3_bin := string_int_build_v3()
    src := os.join_path(os.temp_dir(), 'v3_string_int_or_root_${os.getpid()}.v')
    os.write_file(src, "module main

n := arguments()[1] or { '10' }.int()
println(n)
") or {
        panic(err)
    }
    bin := os.join_path(os.temp_dir(), 'v3_string_int_or_root_${os.getpid()}')
    compile := os.execute('${v3_bin} ${src} -b c -o ${bin}')
    assert compile.exit_code == 0, compile.output
    assert !compile.output.contains('implicit declaration'), compile.output
    run := os.execute(bin)
    assert run.exit_code == 0, run.output
    assert run.output.trim_space() == '10', run.output

    generated := os.read_file(bin + '.c') or { panic(err) }
    assert generated.contains('string__int('), generated
}

fn test_top_level_calls_are_ignored_when_explicit_main_exists() {
    v3_bin := string_int_build_v3()
    src := os.join_path(os.temp_dir(), 'v3_explicit_main_ignores_top_level_${os.getpid()}.v')
    os.write_file(src, "module main

fn ignored_top_level_only() {
    println('ignored')
}

ignored_top_level_only()

fn main() {
    println('entry')
}
") or {
        panic(err)
    }
    bin := os.join_path(os.temp_dir(), 'v3_explicit_main_ignores_top_level_${os.getpid()}')
    compile := os.execute('${v3_bin} ${src} -b c -o ${bin}')
    assert compile.exit_code == 0, compile.output
    run := os.execute(bin)
    assert run.exit_code == 0, run.output
    assert run.output.trim_space() == 'entry', run.output

    generated := os.read_file(bin + '.c') or { panic(err) }
    assert !generated.contains('ignored_top_level_only('), generated
}