using System;
using System.Collections.Generic;
using System.IO;
using System.Reflection;
using UnityEditor;
using UnityEngine;
using UnityEngine.Profiling;
using UnityEngine.Rendering;

namespace Ironspore.Editor
{
    public static class LightingSmoke
    {
        static int step, initialChassis;
        static double nextAt;
        static Result result;
        const string Output = "Docs/QA/Lighting/TestResults/WorldCycles.json";

        public static string Begin()
        {
            if (!EditorApplication.isPlaying || !GameSession.Active || result != null)
                throw new InvalidOperationException("A playing, idle GameSession is required.");
            initialChassis = GameSession.Active.SelectedChassis;
            if (GameSession.Active.InField) GameSession.Active.EndSortie(true);
            result = new Result();
            step = 0;
            nextAt = EditorApplication.timeSinceStartup + 1;
            EditorApplication.update += Tick;
            return "Three chassis and three field/hangar cycles scheduled; report in about 14 seconds.";
        }

        static void Tick()
        {
            if (EditorApplication.timeSinceStartup < nextAt) return;
            nextAt = EditorApplication.timeSinceStartup + 1;
            try
            {
                var game = GameSession.Active;
                if (step >= 12)
                {
                    result.passed = result.rows.TrueForAll(row => row.passed);
                    Finish();
                    return;
                }
                int phase = step % 4;
                if (phase == 0) { game.SelectedChassis = step / 4; game.StartTrial(); }
                if (phase == 1)
                {
                    Snapshot("field", false);
                    typeof(MechPilot).GetProperty("FirstPerson").SetValue(game.Pilot, true);
                }
                if (phase == 2) { Snapshot("first-person", true); game.EndSortie(true); }
                if (phase == 3) Snapshot("hangar", false);
                step++;
            }
            catch (Exception error) { result.error = error.ToString(); Finish(); }
        }

        static void Snapshot(string phase, bool requireShadowOnly)
        {
            var world = GameObject.Find("World");
            int roots = 0, suns = 0, spots = 0, shadowOnly = 0;
            foreach (var candidate in UnityEngine.Object.FindObjectsByType<WorldLighting>())
                if (candidate.gameObject.activeInHierarchy) roots++;
            foreach (var light in world.GetComponentsInChildren<Light>())
            {
                if (light.type == LightType.Directional) suns++;
                if (light.type == LightType.Spot && light.enabled) spots++;
            }
            foreach (var renderer in world.GetComponentsInChildren<Renderer>())
                if (renderer.enabled && renderer.shadowCastingMode == ShadowCastingMode.ShadowsOnly) shadowOnly++;
            int probes = world.GetComponentsInChildren<ReflectionProbe>().Length;
            int cameras = world.GetComponentsInChildren<Camera>().Length;
            result.rows.Add(new Row { phase = phase, chassis = GameSession.Active.SelectedChassis, worlds = roots, suns = suns, enabledSpots = spots, probes = probes, cameras = cameras, shadowOnlyRenderers = shadowOnly, allocatedMiB = Profiler.GetTotalAllocatedMemoryLong() / 1048576.0, reflectionReady = world.GetComponent<WorldLighting>().ReflectionReady, passed = roots == 1 && suns == 1 && probes == 1 && cameras == 1 && spots <= 1 && (!requireShadowOnly || shadowOnly > 0) });
        }

        static void Finish()
        {
            EditorApplication.update -= Tick;
            if (GameSession.Active) GameSession.Active.SelectedChassis = initialChassis;
            Directory.CreateDirectory(Path.GetDirectoryName(Output));
            File.WriteAllText(Output, JsonUtility.ToJson(result, true));
            result = null;
        }

        [Serializable] sealed class Result { public bool passed; public string error; public List<Row> rows = new List<Row>(); }
        [Serializable] sealed class Row
        {
            public string phase;
            public int chassis, worlds, suns, enabledSpots, probes, cameras, shadowOnlyRenderers;
            public double allocatedMiB;
            public bool passed, reflectionReady;
        }
    }
}