using System.Net;
using System.Text;
using System.Text.Json;
using NUnit.Framework;
using SVSim.UnitTests.Infrastructure;

namespace SVSim.UnitTests.Controllers;

public class GiftControllerTests
{
    private const string BaseAuthBlock =
        @"""viewer_id"":""0"",""steam_id"":0,""steam_session_ticket"":""""";

    [Test]
    public async Task GiftTop_returns_five_tutorial_gifts_for_unclaimed_viewer()
    {
        using var factory = new SVSimTestFactory();
        long viewerId = await factory.SeedViewerAsync(tutorialState: 31);
        await factory.SeedTutorialPresentsAsync(viewerId);
        using var client = factory.CreateAuthenticatedClient(viewerId);

        var response = await client.PostAsync("/tutorial/gift_top",
            new StringContent($$"""{"page":1,{{BaseAuthBlock}}}""", Encoding.UTF8, "application/json"));

        Assert.That(response.StatusCode, Is.EqualTo(HttpStatusCode.OK));
        using var doc = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
        var root = doc.RootElement;

        var presents = root.GetProperty("present_list");
        Assert.That(presents.GetArrayLength(), Is.EqualTo(5));

        // Expect the legendary pack entry (present_id 71478630) to be present.
        bool foundLegendaryGift = false;
        foreach (var p in presents.EnumerateArray())
        {
            if (p.GetProperty("present_id").GetString() == "71478630")
            {
                foundLegendaryGift = true;
                Assert.That(p.GetProperty("reward_type").GetString(), Is.EqualTo("4"));
                Assert.That(p.GetProperty("reward_detail_id").GetString(), Is.EqualTo("90001"));
                Assert.That(p.GetProperty("reward_count").GetString(), Is.EqualTo("1"));
                Assert.That(p.GetProperty("item_type").GetInt32(), Is.EqualTo(2));
                Assert.That(p.GetProperty("message").GetString(), Is.EqualTo("For completing the tutorial"));
            }
        }
        Assert.That(foundLegendaryGift, Is.True, "Legendary starter pack gift (71478630) must be in present_list.");

        Assert.That(root.GetProperty("present_history_list").GetArrayLength(), Is.EqualTo(0));
        Assert.That(root.GetProperty("limit_over_present_list").GetArrayLength(), Is.EqualTo(0));
    }

    [Test]
    public async Task GiftReceive_grants_currency_and_items_then_history_is_populated()
    {
        using var factory = new SVSimTestFactory();
        await factory.SeedGlobalsAsync();
        long viewerId = await factory.SeedViewerAsync(tutorialState: 31);
        await factory.SeedTutorialPresentsAsync(viewerId);
        using var client = factory.CreateAuthenticatedClient(viewerId);

        var pre = await factory.GetViewerCurrencyAsync(viewerId);

        var requestJson = $$"""
        {"present_id_array":["71478626","71478627","71478628","71478629","71478630"],"state":1,{{BaseAuthBlock}}}
        """;
        var response = await client.PostAsync("/tutorial/gift_receive",
            new StringContent(requestJson, Encoding.UTF8, "application/json"));

        Assert.That(response.StatusCode, Is.EqualTo(HttpStatusCode.OK));
        using var doc = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
        var root = doc.RootElement;

        // Five received ids echoed.
        var ids = root.GetProperty("received_ids").EnumerateArray()
            .Select(e => e.GetString()).ToHashSet();
        Assert.That(ids, Is.EquivalentTo(new[] { "71478626", "71478627", "71478628", "71478629", "71478630" }));

        // present_list emptied, history populated.
        Assert.That(root.GetProperty("present_list").GetArrayLength(), Is.EqualTo(0));
        Assert.That(root.GetProperty("present_history_list").GetArrayLength(), Is.EqualTo(5));

        // Currency credited: +400 crystals, +100 rupees.
        var post = await factory.GetViewerCurrencyAsync(viewerId);
        Assert.That(post.Crystals - pre.Crystals, Is.EqualTo(400UL));
        Assert.That(post.Rupees - pre.Rupees, Is.EqualTo(100UL));

        // reward_list carries post-state TOTALS, not deltas, per project_wire_reward_list_post_state.
        // After claiming gifts, the crystal/rupy entries in reward_list should equal viewer's post-grant totals.
        var rewardList = root.GetProperty("reward_list").EnumerateArray().ToList();
        var crystalEntry = rewardList.First(e => e.GetProperty("reward_type").GetString() == "1");
        var rupyEntry    = rewardList.First(e => e.GetProperty("reward_type").GetString() == "9");
        Assert.That(crystalEntry.GetProperty("reward_num").GetString(),
            Is.EqualTo(post.Crystals.ToString()),
            "reward_list currency entries must carry POST-STATE TOTALS, not gift deltas (client does direct assignment).");
        Assert.That(rupyEntry.GetProperty("reward_num").GetString(),
            Is.EqualTo(post.Rupees.ToString()));
    }

    [Test]
    public async Task GiftReceive_advances_tutorial_state_from_31_to_41()
    {
        using var factory = new SVSimTestFactory();
        await factory.SeedGlobalsAsync();
        long viewerId = await factory.SeedViewerAsync(tutorialState: 31);
        await factory.SeedTutorialPresentsAsync(viewerId);
        using var client = factory.CreateAuthenticatedClient(viewerId);

        var json = $$"""{"present_id_array":["71478626"],"state":1,{{BaseAuthBlock}}}""";
        var response = await client.PostAsync("/tutorial/gift_receive",
            new StringContent(json, Encoding.UTF8, "application/json"));

        Assert.That(response.StatusCode, Is.EqualTo(HttpStatusCode.OK));
        using var doc = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
        var root = doc.RootElement;

        // Response carries the new step inline.
        Assert.That(root.GetProperty("tutorial_step").GetInt32(), Is.EqualTo(41));
        // Only 1 of 5 gifts claimed → 4 remain unclaimed → badge state must be "still has presents".
        Assert.That(root.GetProperty("is_unreceived_present").GetBoolean(), Is.True,
            "Partial claim leaves 4 gifts unclaimed in present_list — is_unreceived_present " +
            "must reflect that so the client's inbox badge keeps surfacing.");
        Assert.That(root.GetProperty("reward_list").GetArrayLength(), Is.EqualTo(1));
        Assert.That(root.GetProperty("present_list").GetArrayLength(), Is.EqualTo(4));

        // Side effect: viewer state advanced to 41.
        Assert.That(await factory.GetViewerTutorialStateAsync(viewerId), Is.EqualTo(41));
    }

    [Test]
    public async Task GiftReceive_returns_empty_received_ids_on_idempotent_replay()
    {
        using var factory = new SVSimTestFactory();
        await factory.SeedGlobalsAsync();
        long viewerId = await factory.SeedViewerAsync(tutorialState: 31);
        await factory.SeedTutorialPresentsAsync(viewerId);
        using var client = factory.CreateAuthenticatedClient(viewerId);

        var json = $$"""{"present_id_array":["71478626","71478627"],"state":1,{{BaseAuthBlock}}}""";

        // First call grants both gifts.
        await client.PostAsync("/tutorial/gift_receive",
            new StringContent(json, Encoding.UTF8, "application/json"));

        // Second call (replay) must return empty received_ids / total_receive_count_list /
        // reward_list — these lists describe what THIS call granted, not what the client
        // asked for. Echoing requested ids would re-fire the client's "received N gifts"
        // popup and direct-assign the same post-state totals again.
        var second = await client.PostAsync("/tutorial/gift_receive",
            new StringContent(json, Encoding.UTF8, "application/json"));
        Assert.That(second.StatusCode, Is.EqualTo(HttpStatusCode.OK));
        using var doc = JsonDocument.Parse(await second.Content.ReadAsStringAsync());
        var root = doc.RootElement;

        Assert.That(root.GetProperty("received_ids").GetArrayLength(), Is.EqualTo(0),
            "Idempotent re-claim grants nothing → received_ids empty.");
        Assert.That(root.GetProperty("total_receive_count_list").GetArrayLength(), Is.EqualTo(0));
        Assert.That(root.GetProperty("reward_list").GetArrayLength(), Is.EqualTo(0));

        // present_history_list still includes the originally-claimed gifts.
        Assert.That(root.GetProperty("present_history_list").GetArrayLength(), Is.EqualTo(2));
    }

    [Test]
    public async Task GiftReceive_echoes_persisted_tutorial_step_not_hardcoded_41()
    {
        using var factory = new SVSimTestFactory();
        await factory.SeedGlobalsAsync();
        // Viewer is past the tutorial entirely (state=100). The gift_receive endpoint is
        // still reachable via /tutorial/gift_receive — a stale client retry, for instance.
        // The persistence side max-preserves (keeps state at 100); the response must echo
        // 100, not the hardcoded 41 the endpoint used to emit, or the client's tutorial
        // state machine regresses on a no-op retry.
        long viewerId = await factory.SeedViewerAsync(tutorialState: 100);
        await factory.SeedTutorialPresentsAsync(viewerId);
        using var client = factory.CreateAuthenticatedClient(viewerId);

        var json = $$"""{"present_id_array":["71478626"],"state":1,{{BaseAuthBlock}}}""";
        var response = await client.PostAsync("/tutorial/gift_receive",
            new StringContent(json, Encoding.UTF8, "application/json"));

        Assert.That(response.StatusCode, Is.EqualTo(HttpStatusCode.OK));
        using var doc = JsonDocument.Parse(await response.Content.ReadAsStringAsync());
        Assert.That(doc.RootElement.GetProperty("tutorial_step").GetInt32(), Is.EqualTo(100));
        Assert.That(await factory.GetViewerTutorialStateAsync(viewerId), Is.EqualTo(100));
    }

    [Test]
    public async Task GiftReceive_with_pre_owned_item_increments_existing_row()
    {
        using var factory = new SVSimTestFactory();
        await factory.SeedGlobalsAsync();
        long viewerId = await factory.SeedViewerAsync(tutorialState: 31);

        // Seed item 1 (= the 3-item gift's reward_detail_id) with count=5 pre-existing.
        // Any non-tutorial source could leave a viewer here — battlepass, future reward,
        // admin import. Gift 71478628 grants +3 of item 1; the existing row must be
        // found and incremented, not duplicated. The (ViewerId, ItemId) unique index
        // added 2026-05-25 would otherwise throw on SaveChanges → 500 to the client.
        await factory.SeedOwnedItemAsync(viewerId, itemId: 1, count: 5, itemName: "PreOwnedItem");
        await factory.SeedTutorialPresentsAsync(viewerId);

        using var client = factory.CreateAuthenticatedClient(viewerId);

        var json = $$"""{"present_id_array":["71478628"],"state":1,{{BaseAuthBlock}}}""";
        var response = await client.PostAsync("/tutorial/gift_receive",
            new StringContent(json, Encoding.UTF8, "application/json"));

        var bodyStr = await response.Content.ReadAsStringAsync();
        Assert.That(response.StatusCode, Is.EqualTo(HttpStatusCode.OK), bodyStr);

        // Existing row was incremented to 8 (5 + 3), not duplicated.
        Assert.That(await factory.GetOwnedItemCountAsync(viewerId, 1), Is.EqualTo(8),
            "Pre-existing OwnedItemEntry must be found via the ThenIncluded Item nav; " +
            "otherwise RewardGrantService falls through to add a new row and the " +
            "(ViewerId, ItemId) unique index throws on SaveChanges.");

        // reward_list reflects the post-state total (8), not the gift delta (3).
        using var doc = JsonDocument.Parse(bodyStr);
        var itemEntry = doc.RootElement.GetProperty("reward_list").EnumerateArray()
            .First(e => e.GetProperty("reward_type").GetString() == "4"
                     && e.GetProperty("reward_id").GetString() == "1");
        Assert.That(itemEntry.GetProperty("reward_num").GetString(), Is.EqualTo("8"),
            "RewardNum carries the POST-STATE TOTAL — client direct-assigns it onto the " +
            "cached count, so emitting the delta would clobber on-screen inventory.");
    }

    [Test]
    public async Task GiftReceive_second_call_with_same_ids_does_not_double_grant()
    {
        using var factory = new SVSimTestFactory();
        await factory.SeedGlobalsAsync();
        long viewerId = await factory.SeedViewerAsync(tutorialState: 31);
        await factory.SeedTutorialPresentsAsync(viewerId);
        using var client = factory.CreateAuthenticatedClient(viewerId);

        var preFirst = await factory.GetViewerCurrencyAsync(viewerId);
        var json = $$"""{"present_id_array":["71478626","71478627"],"state":1,{{BaseAuthBlock}}}""";

        await client.PostAsync("/tutorial/gift_receive", new StringContent(json, Encoding.UTF8, "application/json"));
        var midPost = await factory.GetViewerCurrencyAsync(viewerId);
        Assert.That(midPost.Crystals - preFirst.Crystals, Is.EqualTo(400UL));
        Assert.That(midPost.Rupees - preFirst.Rupees, Is.EqualTo(100UL));

        var second = await client.PostAsync("/tutorial/gift_receive", new StringContent(json, Encoding.UTF8, "application/json"));
        Assert.That(second.StatusCode, Is.EqualTo(HttpStatusCode.OK));
        var finalPost = await factory.GetViewerCurrencyAsync(viewerId);
        Assert.That(finalPost.Crystals, Is.EqualTo(midPost.Crystals), "Second claim of same present_ids must not re-grant.");
        Assert.That(finalPost.Rupees, Is.EqualTo(midPost.Rupees));
    }
}