using System;
using System.Collections.Generic;
using Paca.Browser.Tabs;
using Xunit;

namespace Paca.Tests.Browser;

public class ChromeTabDiscardPolicyTests
{
    [Fact]
    public void Policy_Evaluates_Eligible_Tabs_Correctly()
    {
        var policy = new ChromeTabDiscardPolicy(MemorySaverMode.Moderate);

        var activeTab = new DiscardableTabInfo("tab-1", "https://google.com", IsActive: true, IsPinned: false, IsAudioPlaying: false, LastAccessed: DateTime.UtcNow.AddHours(-1));
        var pinnedTab = new DiscardableTabInfo("tab-2", "https://github.com", IsActive: false, IsPinned: true, IsAudioPlaying: false, LastAccessed: DateTime.UtcNow.AddHours(-1));
        var audioTab = new DiscardableTabInfo("tab-3", "https://youtube.com", IsActive: false, IsPinned: false, IsAudioPlaying: true, LastAccessed: DateTime.UtcNow.AddHours(-1));
        var idleTab = new DiscardableTabInfo("tab-4", "https://news.com", IsActive: false, IsPinned: false, IsAudioPlaying: false, LastAccessed: DateTime.UtcNow.AddMinutes(-35));
        var recentTab = new DiscardableTabInfo("tab-5", "https://blog.com", IsActive: false, IsPinned: false, IsAudioPlaying: false, LastAccessed: DateTime.UtcNow.AddMinutes(-5));

        // Active tab must never be discarded
        Assert.False(policy.CanDiscard(activeTab, DateTime.UtcNow));
        // Pinned tab must never be discarded
        Assert.False(policy.CanDiscard(pinnedTab, DateTime.UtcNow));
        // Audio playing tab must never be discarded
        Assert.False(policy.CanDiscard(audioTab, DateTime.UtcNow));
        // Idle tab (>30 min) in Moderate mode can be discarded
        Assert.True(policy.CanDiscard(idleTab, DateTime.UtcNow));
        // Recent tab (<30 min) in Moderate mode cannot be discarded
        Assert.False(policy.CanDiscard(recentTab, DateTime.UtcNow));
    }

    [Fact]
    public void MemorySaverMode_Thresholds_Work_As_Expected()
    {
        var disabled = new ChromeTabDiscardPolicy(MemorySaverMode.Disabled);
        var aggressive = new ChromeTabDiscardPolicy(MemorySaverMode.Aggressive); // 5 min
        var conservative = new ChromeTabDiscardPolicy(MemorySaverMode.Conservative); // 2 hours

        var tenMinIdleTab = new DiscardableTabInfo("t-1", "https://site.org", IsActive: false, IsPinned: false, IsAudioPlaying: false, LastAccessed: DateTime.UtcNow.AddMinutes(-10));

        Assert.False(disabled.CanDiscard(tenMinIdleTab, DateTime.UtcNow));
        Assert.True(aggressive.CanDiscard(tenMinIdleTab, DateTime.UtcNow));
        Assert.False(conservative.CanDiscard(tenMinIdleTab, DateTime.UtcNow));
    }

    [Fact]
    public void DiscardManager_Tracks_Discarded_And_Reactivated_Tabs()
    {
        var manager = new ChromeTabDiscardManager(MemorySaverMode.Aggressive);

        var tab = new DiscardableTabInfo("t-1", "https://site.org", IsActive: false, IsPinned: false, IsAudioPlaying: false, LastAccessed: DateTime.UtcNow.AddMinutes(-10));

        Assert.False(manager.IsDiscarded("t-1"));

        var discarded = manager.TryDiscard(tab, DateTime.UtcNow);
        Assert.True(discarded);
        Assert.True(manager.IsDiscarded("t-1"));
        Assert.Equal(1, manager.DiscardedCount);

        // Reactivating tab restores its active state
        var restored = manager.Reactivate("t-1");
        Assert.True(restored);
        Assert.False(manager.IsDiscarded("t-1"));
        Assert.Equal(0, manager.DiscardedCount);
    }

    [Theory]
    [InlineData("chrome://discards", ChromeInternalAction.Discards)]
    [InlineData("paca://discards", ChromeInternalAction.Discards)]
    public void ChromeInternalUrlRouter_Routes_Discards(string url, ChromeInternalAction expected)
    {
        Assert.True(ChromeInternalUrlRouter.IsInternal(url));
        Assert.Equal(expected, ChromeInternalUrlRouter.Route(url));
    }

    [Fact]
    public void Omnibox_Suggests_Discard_Tabs_Action()
    {
        var actions = OmniboxActionEvaluator.GetMatchingActions("메모리 절약");
        Assert.NotEmpty(actions);
        Assert.Contains(actions, a => a.ActionId == "action:discard-tabs");
    }
}