using System.Collections.Generic;
using UnityEngine;

namespace AibisDream.FrameAnimation
{
    [CreateAssetMenu(fileName = "FrameClip", menuName = "AibisDream/Frame Animation/Frame Clip")]
    public sealed class FrameClip : ScriptableObject
    {
        [SerializeField] private string id = string.Empty;
        [SerializeField] private string displayName = string.Empty;
        [SerializeField] private List<FrameAnimationFrame> frames = new List<FrameAnimationFrame>();
        [SerializeField] private float speed = 1f;
        [SerializeField] private FrameClipEndBehavior defaultEndBehavior = FrameClipEndBehavior.HoldLastFrame;
        [SerializeField] private bool hasImportInfo;
        [SerializeField] private FrameClipImportInfo importInfo;
        [SerializeField] private bool hasStandaloneImportSource;
        [SerializeField] private FrameClipImportSource standaloneImportSource;

        public string Id => id;
        public string DisplayName => displayName;
        public IReadOnlyList<FrameAnimationFrame> Frames => frames;
        public float Speed => speed;
        public FrameClipEndBehavior DefaultEndBehavior => defaultEndBehavior;
        public FrameClipImportInfo ImportInfo => hasImportInfo ? importInfo : null;
        public bool IsImported => ImportInfo != null;
        public FrameClipImportSource StandaloneImportSource =>
            hasStandaloneImportSource ? standaloneImportSource : null;
        public bool HasStandaloneImportSource => StandaloneImportSource != null;

        public int FrameCount => frames?.Count ?? 0;

        public long TotalDurationMs
        {
            get
            {
                long total = 0;
                if (frames == null)
                {
                    return total;
                }

                foreach (var frame in frames)
                {
                    if (frame != null)
                    {
                        total += frame.DurationMs;
                    }
                }

                return total;
            }
        }

        private void OnEnable()
        {
            frames ??= new List<FrameAnimationFrame>();
            if (!hasImportInfo && importInfo != null &&
                (!string.IsNullOrEmpty(importInfo.ImportSourceId) ||
                 !string.IsNullOrEmpty(importInfo.SourceTagName) ||
                 importInfo.IsMissingFromSource))
            {
                // Compatibility for phase-two assets created before the explicit presence flag existed.
                hasImportInfo = true;
            }
        }

        internal void Configure(
            string clipId,
            string clipDisplayName,
            IEnumerable<FrameAnimationFrame> clipFrames,
            float clipSpeed = 1f,
            FrameClipEndBehavior endBehavior = FrameClipEndBehavior.HoldLastFrame,
            FrameClipImportInfo clipImportInfo = null)
        {
            id = clipId ?? string.Empty;
            displayName = clipDisplayName ?? id;
            frames = clipFrames != null
                ? new List<FrameAnimationFrame>(clipFrames)
                : new List<FrameAnimationFrame>();
            speed = clipSpeed;
            defaultEndBehavior = endBehavior;
            importInfo = clipImportInfo;
            hasImportInfo = clipImportInfo != null;
        }

        internal void ReplaceImportedFrames(
            IEnumerable<FrameAnimationFrame> importedFrames,
            string importSourceId,
            string sourceTagName)
        {
            frames = importedFrames != null
                ? new List<FrameAnimationFrame>(importedFrames)
                : new List<FrameAnimationFrame>();
            importInfo ??= new FrameClipImportInfo(importSourceId, sourceTagName, false);
            importInfo.Update(importSourceId, sourceTagName, false);
            hasImportInfo = true;
        }

        internal void SetImportMissingState(bool isMissing)
        {
            if (hasImportInfo && importInfo != null)
            {
                importInfo.Update(importInfo.ImportSourceId, importInfo.SourceTagName, isMissing);
            }
        }

        internal void SetId(string value)
        {
            id = value ?? string.Empty;
        }

        internal void SetDisplayName(string value)
        {
            displayName = value ?? string.Empty;
        }

        internal void SetFrames(IEnumerable<FrameAnimationFrame> value)
        {
            frames = value != null
                ? new List<FrameAnimationFrame>(value)
                : new List<FrameAnimationFrame>();
        }

        internal FrameClipImportSource GetOrCreateStandaloneImportSource()
        {
            standaloneImportSource ??= new FrameClipImportSource();
            hasStandaloneImportSource = true;
            return standaloneImportSource;
        }

        internal void ClearStandaloneImportSource()
        {
            hasStandaloneImportSource = false;
            standaloneImportSource = null;
        }
    }
}