// SPDX-License-Identifier: LGPL-3.0-only
// SPDX-FileCopyrightText: Copyright (C) 2026 Catcrafts®

// Watches and samples resolve by path, including into their values
// ("bodies[1].pos.y" against the watch "bodies"), and set the same way:
// writing one member of a watched struct writes the whole struct back. Sets
// respect bounds and read-only watches, computed watches set through their
// setter (which may refuse), samples keep a frame-stamped history, unknown
// paths get a suggestion, and a Group's watches go with it.
import std;
import Crafter.Debug;
using namespace Crafter::Debug;

namespace {
    std::int32_t failures = 0;

    void Check(bool ok, std::string_view what) {
        std::println("{} {}", ok ? "PASS" : "FAIL", what);
        if (!ok) ++failures;
    }

    struct Vec3 {
        float x = 0;
        float y = 0;
        float z = 0;
    };

    struct Body {
        std::int32_t id = 0;
        Vec3 pos;
    };

    float gravity = -9.81F;
    const std::int32_t build = 7;
    std::vector<Body> bodies = { { 1, { 0, 1, 0 } }, { 2, { 3, 4, 5 } } };
    std::int32_t lives = 3;

    Detail::Registry& registry() {
        return Detail::Registry::Instance();
    }
}

int main() {
    Watch("physics.gravity", gravity, { .min = -50, .max = 0, .help = "m/s^2" });
    Watch("build", build);
    Watch("bodies", bodies);
    Watch("lives", [] { return lives; }, [](const std::int32_t& value) -> Result<> {
        if (value < 0) return Error{ "Negative", "lives cannot be negative" };
        lives = value;
        return {};
    });
    Watch("score", [] { return 1234; });

    Check(registry().Resolve("physics.gravity").value.AsNumber() == static_cast<double>(-9.81F), "a variable watch reads the variable");
    Check(registry().Resolve("bodies[1].pos.y").value.AsNumber() == 4, "a path reads into a watched value");
    Check(registry().Resolve("bodies[1]").value.Find("id")->AsInteger() == 2, "an index reads an item");

    Check(!registry().Set("physics.gravity", Value(-3.5)) && gravity == -3.5F, "a set writes the variable");
    const auto bounded = registry().Set("physics.gravity", Value(10));
    Check(bounded && bounded->find("outside") != std::string::npos && gravity == -3.5F, "a set outside the bounds is refused");
    Check(registry().Set("build", Value(8)) == std::optional<std::string>("'build' is read-only") && build == 7, "a const variable's watch is read-only");
    Check(!registry().Set("bodies[0].pos.x", Value(9)) && bodies[0].pos.x == 9 && bodies[0].pos.y == 1, "a set into a member writes back the whole value");
    const auto wrongType = registry().Set("physics.gravity", Value("down"));
    Check(wrongType && wrongType->find("expected a number") != std::string::npos, "a set of the wrong type is refused");

    Check(!registry().Set("lives", Value(5)) && lives == 5, "a computed watch sets through its setter");
    const auto negative = registry().Set("lives", Value(-1));
    Check(negative && negative->find("lives cannot be negative") != std::string::npos && lives == 5, "a setter can refuse");
    Check(registry().Set("score", Value(1)) == std::optional<std::string>("'score' is read-only"), "a getter-only watch is read-only");

    const auto missing = registry().Resolve("physics.gravty");
    Check(!missing.Ok() && missing.error.find("did you mean 'physics.gravity'") != std::string::npos, "an unknown path gets a suggestion");
    const auto badMember = registry().Resolve("bodies[0].pos.w");
    Check(!badMember.Ok() && badMember.error.find("has no member 'w'") != std::string::npos, "an unknown member is named");
    const auto outOfRange = registry().Resolve("bodies[5]");
    Check(!outOfRange.Ok() && outOfRange.error.find("2 items") != std::string::npos, "an index out of range gives the size");

    for (std::uint64_t frame = 1; frame <= 3; ++frame) {
        Detail::SetFrame(frame);
        Sample("xpbd.residual", static_cast<double>(frame) / 10);
    }
    Check(registry().Resolve("xpbd.residual").value.AsNumber() == 0.3, "a sample resolves to its latest value");
    const auto history = registry().SampleHistory("xpbd.residual");
    Check(history.size() == 3 && history.front().frame == 1 && history.back().frame == 3, "a sample keeps a frame-stamped history");

    Check(registry().Watches("physics.*").size() == 1 && registry().Watches("*").size() == 5, "watches can be listed by glob");
    Check(registry().Watches("physics.gravity").front()->help == "m/s^2" && registry().Watches("physics.gravity").front()->type.Find("maximum") != nullptr,
          "a watch carries its help and bounds");

    {
        struct Fort {
            std::int32_t hp = 100;
            Group debug{ "fort1" };
            Fort() { debug.Watch("core.hp", hp); }
        };
        Fort fort;
        Check(registry().Resolve("fort1.core.hp").value.AsInteger() == 100, "a Group prefixes its watches");
    }
    Check(!registry().Resolve("fort1.core.hp").Ok(), "a Group's watches go with it");

    return failures == 0 ? 0 : 1;
}