import "@std/mem"
import "@std/arraylist"
import "@std/testing"
import "@source/ast"
import "@source/diagnostics"
import "@source/ir"
import "@source/interpreter"

@hide:file
owned_text proc(text []u8) arraylist.ArrayList(u8) ! mem.AllocError {
    bytes := arraylist.init(u8, mem.c_allocator)
    errdefer arraylist.deinit(&bytes)
    try arraylist.reserve(&bytes, text.len)
    for (text) |byte| try arraylist.append(&bytes, byte)
    return bytes
}

keeps_package_declarations_distinct_and_ir_independent test {
    diagnostic_store := diagnostics.init(mem.c_allocator)
    defer diagnostics.deinit(&diagnostic_store)
    first := try owned_text("value :: 21\nmain proc() int { return value * 2 }")
    defer arraylist.deinit(&first)
    second := try owned_text("value :: 3\nmain proc() int { return value * 2 }")
    defer arraylist.deinit(&second)
    sibling := try owned_text("helper proc() int { return 7 }")
    defer arraylist.deinit(&sibling)
    path [9]mut u8 := undefined
    memcopy!(path[..], "first.hon")
    session := init(mem.c_allocator)
    # the IR must outlive the compilation, including source buffers and interned names.
    modules [2]mut ir.Module := undefined
    {
        defer deinit(&session)
        root :: try add_package(&session)
        dependency :: try add_package(&session)
        left :: try add_source(&session, root, path[..], &first, &diagnostic_store)
        right :: try add_source(&session, dependency, "second.hon", &second, &diagnostic_store)
        third :: try add_source(&session, root, "sibling.hon", &sibling, &diagnostic_store)
        path[0] = 'X'
        try testing.expect_equal(0, first.capacity)
        try testing.expect_equal(0, first.items.len)
        try testing.expect(mem.eql(source(&session, left).path, "first.hon"))
        try testing.expect_equal(root, source(&session, left).package)
        try testing.expect_equal(dependency, source(&session, right).package)
        try testing.expect_equal(root, source(&session, third).package)
        try testing.expect_equal(left, session.packages.items[usize(root)].sources.items[0])
        try testing.expect_equal(third, session.packages.items[usize(root)].sources.items[1])
        a :: declaration(&session, left, 0)
        b :: declaration(&session, right, 0)
        try testing.expect(a.source != b.source)
        tree :: ast.view(&session.builder, source(&session, left).root)
        try testing.expect_equal(ast.name_id(&tree, a.node), ast.name_id(&tree, b.node))
        try testing.expect(mem.eql(ast.source_text(&tree, ast.statement_decl(&tree, a.node).span), "value :: 21"))
        try testing.expect(mem.eql(ast.source_text(&tree, ast.statement_decl(&tree, b.node).span), "value :: 3"))
        modules[0] = try compile(&session, root, &diagnostic_store)
        errdefer ir.deinit(&modules[0])
        modules[1] = try compile(&session, dependency, &diagnostic_store)
    }
    defer ir.deinit(&modules[0])
    defer ir.deinit(&modules[1])
    try testing.expect_equal(0, diagnostics.count(&diagnostic_store))
    left_result := try interpreter.run(mem.c_allocator, &modules[0], &diagnostic_store)
    defer interpreter.deinit(&left_result)
    right_result := try interpreter.run(mem.c_allocator, &modules[1], &diagnostic_store)
    defer interpreter.deinit(&right_result)
    try testing.expect(left_result.trap == null and right_result.trap == null)
    try testing.expect_equal(i64(42), left_result.value.data.integer)
    try testing.expect_equal(i64(6), right_result.value.data.integer)
}

dependency_traps_keep_original_spans_and_remain_demand_driven test {
    mains [2][]u8 :: [
        "dep :: import \"../dependency\"\nmain proc() int { return dep.fail(false) }\n",
        "dep :: import \"../dependency\"\nmain proc() int { return dep.fail(true) }\n",
    ]
    prefix :: "\nfail proc(take bool) int {\n    if take {\n        return "
    for (mains) |main, index| {
        diagnostic_store := diagnostics.init(mem.c_allocator)
        defer diagnostics.deinit(&diagnostic_store)
        module ir.Module := undefined
        dependency_source SourceId := undefined
        original diagnostics.DiagnosticId := undefined
        {
            session := init(mem.c_allocator)
            defer deinit(&session)
            root :: try add_package(&session)
            dependency :: try add_package(&session)
            root_bytes := try owned_text(main)
            defer arraylist.deinit(&root_bytes)
            dependency_bytes := try owned_text(
                "\nfail proc(take bool) int {\n    if take {\n        return missing\n    }\n    return 42\n}\n",
            )
            defer arraylist.deinit(&dependency_bytes)
            root_source :: try add_source(&session, root, "app/main.hon", &root_bytes, &diagnostic_store)
            dependency_source = try add_source(&session, dependency, "dependency/fail.hon", &dependency_bytes, &diagnostic_store)
            try arraylist.append(&session.imports, Import{
                node = declaration(&session, root_source, 0).node,
                target = dependency,
            })
            module = try compile(&session, root, &diagnostic_store)
        }
        defer ir.deinit(&module)
        try testing.expect_equal(1, diagnostics.count(&diagnostic_store))
        original = diagnostics.DiagnosticId(0)
        diagnostic :: diagnostics.get(&diagnostic_store, original)?
        try testing.expect_equal(diagnostics.Code.unknown_name, diagnostic.code)
        try testing.expect_equal(dependency_source, diagnostic.span.source)
        try testing.expect_equal(u32(prefix.len), diagnostic.span.start)
        try testing.expect_equal(u32(prefix.len + 7), diagnostic.span.end)
        outcome := try interpreter.run(mem.c_allocator, &module, &diagnostic_store)
        defer interpreter.deinit(&outcome)
        try testing.expect_equal(1, diagnostics.count(&diagnostic_store))
        if (index == 0) {
            try testing.expect(outcome.trap == null)
            try testing.expect_equal(i64(42), outcome.value.data.integer)
        } else {
            try testing.expect_equal(original, outcome.trap?)
        }
    }
}