// Expect retcode = 0

// 显式装箱值：运行期格式化用的最小 ADT。调用方显式构造（如 Value.int(x)），
// 库内用 match 分派。不做隐式装箱、不带运行期类型系统。
// Str 借用 ByteView，不拥有存储；Ptr 是类型擦除指针。

type .{ .ByteView } = @import("byte_view.spl");

type Value = enum {
    Int: i64,
    Uint: u64,
    Bool: bool,
    Char: u8,
    Str: ByteView,
    Ptr: *any,
}

fn int(value: i64): Value {
    ret .Int(value);
}

fn uint(value: u64): Value {
    ret .Uint(value);
}

fn boolean(value: bool): Value {
    ret .Bool(value);
}

fn char(value: u8): Value {
    ret .Char(value);
}

fn str(bytes: []u8): Value {
    ret .Str(ByteView.from_slice(bytes));
}

fn str_view(view: ByteView): Value {
    ret .Str(view);
}

fn addr(value: *any): Value {
    ret .Ptr(value);
}

// ---- 测试 ----

fn test_int_and_uint() {
    match int(-5) {
        .Int(v) => { @assert(v == -5, "int payload"); },
        _ => { @assert(false, "expected int"); },
    }
    match uint(5) {
        .Uint(v) => { @assert(v == 5, "uint payload"); },
        _ => { @assert(false, "expected uint"); },
    }
}

fn test_scalars() {
    match boolean(true) {
        .Bool(v) => { @assert(v, "bool payload"); },
        _ => { @assert(false, "expected bool"); },
    }
    match char('A') {
        .Char(v) => { @assert(v == 'A', "char payload"); },
        _ => { @assert(false, "expected char"); },
    }
}

fn test_borrowed_str() {
    var text: [3]u8 = .[104, 105, 0];
    var s = str(text[0..2]);
    match s {
        .Str(view) => {
            @assert(view.len == 2 && view.ptr[0] == 104 && view.ptr[1] == 105,
                    "str payload borrows");
        },
        _ => { @assert(false, "expected str"); },
    }
    @assert(text[0] == 104, "source untouched");
}

fn test_ptr() {
    var x: i32 = 7;
    match addr(&x as *any) {
        .Ptr(p) => { @assert((p as *i32).* == 7, "ptr payload"); },
        _ => { @assert(false, "expected ptr"); },
    }
    match addr(null) {
        .Ptr(p) => { @assert(p == null, "null ptr payload"); },
        _ => { @assert(false, "expected ptr"); },
    }
}

fn main() {
    test_int_and_uint();
    test_scalars();
    test_borrowed_str();
    test_ptr();
}