using System;
using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Threading;
using TMPro;
using UnityEngine;
using UnityEngine.Networking;
using UnityEngine.SceneManagement;
using UnityEngine.UI;

public class SongCreatorManager : MonoBehaviour
{
    [Header("Audio Source")]
    [SerializeField] private TMP_Dropdown audioDropdown;
    [SerializeField] private Button       refreshBtn;
    [SerializeField] private TMP_Text     inputPathHint;

    [Header("Audio — Local File")]
    [SerializeField] private Button   filePickerBtn;
    [SerializeField] private TMP_Text addStatusText;

    [Header("Audio — URL")]
    [SerializeField] private TMP_InputField urlInput;
    [SerializeField] private Button         urlDownloadBtn;

    [Header("Metadata")]
    [SerializeField] private TMP_InputField titleInput;
    [SerializeField] private TMP_InputField artistInput;
    [SerializeField] private TMP_InputField bpmInput;

    [Header("Difficulty")]
    [SerializeField] private Toggle toggleNormal;
    [SerializeField] private Toggle toggleHard;
    [SerializeField] private Toggle toggleExpert;
    [SerializeField] private Toggle toggleExpertPlus;

    [Header("Actions")]
    [SerializeField] private Button generateButton;
    [SerializeField] private Button manualEditorButton;
    [SerializeField] private Button backButton;
    [SerializeField] private string menuSceneName = "Menu";

    [Header("Progress")]
    [SerializeField] private GameObject progressGroup;
    [SerializeField] private TMP_Text   statusText;
    [SerializeField] private Slider     progressSlider;

    [Header("References")]
    [SerializeField] private BeatSageUploader beatSageUploader;
    [SerializeField] private NasPublisher     nasPublisher;

    private static readonly Color NeonBg       = new Color(0.05f, 0.82f, 0.95f, 0.42f);
    private static readonly Color DarkButtonBg = new Color(0.09f, 0.22f, 0.27f, 0.66f);
    private static readonly Color DisabledBg   = new Color(0.06f, 0.12f, 0.15f, 0.48f);
    private static readonly Color ButtonText   = new Color(0.92f, 1.0f, 1.0f, 1.0f);
    private static readonly Color MutedText    = new Color(0.66f, 0.80f, 0.84f, 0.76f);
    private static readonly Color NeonOutline  = new Color(0.25f, 0.96f, 1.0f, 0.42f);

    private static string InputPath =>
        Path.Combine(Application.persistentDataPath, "input");

    private readonly List<string> audioFiles = new();
    private string _pendingFilePath;

    private void OnValidate()
    {
        ApplyButtonStyles();
    }

    private void Start()
    {
        ApplyButtonStyles();
        Directory.CreateDirectory(InputPath);

        if (inputPathHint != null)
            inputPathHint.text = $"Path: {InputPath}";

        refreshBtn?.onClick.AddListener(RefreshAudioList);
        generateButton?.onClick.AddListener(OnGenerateClicked);
        backButton?.onClick.AddListener(() => SceneManager.LoadScene(menuSceneName));
        filePickerBtn?.onClick.AddListener(OnFilePickerClicked);
        urlDownloadBtn?.onClick.AddListener(OnUrlDownloadClicked);

        if (progressGroup != null) progressGroup.SetActive(false);
        RefreshAudioList();
    }

    private void Update()
    {
        if (_pendingFilePath != null)
        {
            CopyToInput(_pendingFilePath);
            _pendingFilePath = null;
        }
    }

    private void RefreshAudioList()
    {
        audioFiles.Clear();
        audioDropdown?.ClearOptions();

        var options = new List<string>();
        foreach (string f in Directory.GetFiles(InputPath, "*.mp3"))
        {
            audioFiles.Add(f);
            options.Add(Path.GetFileNameWithoutExtension(f));
        }

        if (options.Count == 0) options.Add("-- no .mp3 files --");
        audioDropdown?.AddOptions(options);
    }

    private void OnGenerateClicked()
    {
        string directUrl = urlInput != null ? urlInput.text.Trim() : "";
        bool   hasUrl    = !string.IsNullOrEmpty(directUrl);
        bool   hasFile   = audioFiles.Count > 0;

        if (!hasUrl && !hasFile) { SetStatus("No audio source. Add a file or enter a URL."); return; }

        // BPM input is optional — Beat Sage auto-detects from audio; use as fallback only
        float.TryParse(bpmInput?.text, out float bpmHint);

        var diffs = new List<string> { "normal", "hard", "expert", "expertplus" };

        if (hasUrl)
        {
            if (!Uri.TryCreate(directUrl, UriKind.Absolute, out var uri) ||
                (uri.Scheme != "http" && uri.Scheme != "https"))
            { SetStatus("Invalid URL."); return; }

            StartCoroutine(GenerateFlowFromUrl(uri.AbsoluteUri, bpmHint, diffs));
        }
        else
        {
            StartCoroutine(GenerateFlow(audioFiles[audioDropdown.value], bpmHint, diffs));
        }
    }

    private IEnumerator GenerateFlowFromUrl(string audioUrl, float bpm, List<string> diffs)
    {
        SetInteractable(false);
        if (progressGroup != null) progressGroup.SetActive(true);

        Dictionary<string, List<NoteData>> maps = null;
        bool failed = false;

        yield return beatSageUploader.UploadFromUrl(
            audioUrl, diffs, bpm,
            onProgress: p =>
            {
                if (progressSlider != null) progressSlider.value = p * 0.8f;
                SetStatus($"{beatSageUploader.CurrentStatus}  ({(int)(p * 80)}%)");
            },
            onComplete: result => maps = result,
            onError:    err    => { SetStatus($"Error: {err}"); failed = true; });

        if (failed) { SetInteractable(true); yield break; }

        SongInfo song = BuildSongInfo(audioUrl, bpm, maps);

        yield return nasPublisher.Publish(
            song, null, maps,
            onProgress: p =>
            {
                if (progressSlider != null) progressSlider.value = 0.8f + p * 0.2f;
                SetStatus($"[4/4] Uploading to NAS...  ({(int)((0.8f + p * 0.2f) * 100)}%)");
            },
            onComplete: () =>
            {
                if (progressSlider != null) progressSlider.value = 1f;
                SetStatus($"Done! '{song.title}' created successfully.");
            },
            onError: err => { SetStatus($"NAS upload failed: {err}"); failed = true; });

        SetInteractable(true);
    }

    private IEnumerator GenerateFlow(string audioPath, float bpm, List<string> diffs)
    {
        SetInteractable(false);
        if (progressGroup != null) progressGroup.SetActive(true);

        Dictionary<string, List<NoteData>> maps = null;
        bool failed = false;

        yield return beatSageUploader.Upload(
            audioPath, diffs, bpm,
            onProgress: p =>
            {
                if (progressSlider != null) progressSlider.value = p * 0.8f;
                SetStatus($"{beatSageUploader.CurrentStatus}  ({(int)(p * 80)}%)");
            },
            onComplete: result => maps = result,
            onError:    err    => { SetStatus($"Error: {err}"); failed = true; });

        if (failed) { SetInteractable(true); yield break; }

        SongInfo song = BuildSongInfo(audioPath, bpm, maps);

        yield return nasPublisher.Publish(
            song, audioPath, maps,
            onProgress: p =>
            {
                if (progressSlider != null) progressSlider.value = 0.8f + p * 0.2f;
                SetStatus($"[4/4] Uploading to NAS...  ({(int)((0.8f + p * 0.2f) * 100)}%)");
            },
            onComplete: () =>
            {
                if (progressSlider != null) progressSlider.value = 1f;
                SetStatus($"Done! '{song.title}' created successfully.");
            },
            onError: err => { SetStatus($"NAS upload failed: {err}"); failed = true; });

        SetInteractable(true);
    }

    private SongInfo BuildSongInfo(string audioPath, float fallbackBpm,
        Dictionary<string, List<NoteData>> maps)
    {
        // Prefer values from info.dat (auto-detected by Beat Sage); UI inputs override if non-empty
        var meta   = beatSageUploader != null ? beatSageUploader.LastMetadata : null;
        string uiTitle  = titleInput?.text.Trim()  ?? "";
        string uiArtist = artistInput?.text.Trim() ?? "";
        float.TryParse(bpmInput?.text, out float uiBpm);

        string title  = !string.IsNullOrEmpty(uiTitle)  ? uiTitle  : (meta?.title  ?? "");
        string artist = !string.IsNullOrEmpty(uiArtist) ? uiArtist : (meta?.artist ?? "");
        float  bpm    = (meta != null && meta.bpm > 0)  ? meta.bpm : (uiBpm > 0 ? uiBpm : fallbackBpm);

        // Fallback id from filename if title is still empty
        if (string.IsNullOrEmpty(title) && !string.IsNullOrEmpty(audioPath))
            title = Path.GetFileNameWithoutExtension(audioPath);
        if (string.IsNullOrEmpty(title))
            title = $"song_{DateTime.Now:yyyyMMdd_HHmmss}";

        string id = title.ToLower().Replace(" ", "_");

        var diffMap = new DifficultyMap();
        foreach (var kv in maps)
        {
            var info = new DifficultyInfo { noteCount = kv.Value.Count };
            switch (kv.Key)
            {
                case "normal":     diffMap.normal     = info; break;
                case "hard":       diffMap.hard       = info; break;
                case "expert":     diffMap.expert     = info; break;
                case "expertplus": diffMap.expertplus = info; break;
            }
        }

        return new SongInfo
        {
            id           = id,
            title        = title,
            artist       = artist,
            bpm          = bpm,
            audioFile    = $"music/{id}.mp3",
            difficulties = diffMap,
            addedAt      = DateTime.Now.ToString("yyyy-MM-dd"),
        };
    }

    private void SetStatus(string msg) { if (statusText != null) statusText.text = msg; }

    private void SetInteractable(bool value)
    {
        if (generateButton     != null) generateButton.interactable     = value;
        if (audioDropdown      != null) audioDropdown.interactable      = value;
        if (refreshBtn         != null) refreshBtn.interactable         = value;
        if (filePickerBtn      != null) filePickerBtn.interactable      = value;
        if (urlDownloadBtn     != null) urlDownloadBtn.interactable     = value;
        ApplyButtonStyles();
    }

    private void OnFilePickerClicked()
    {
#if UNITY_EDITOR
        string path = UnityEditor.EditorUtility.OpenFilePanel("Select audio file", "", "mp3");
        if (!string.IsNullOrEmpty(path)) CopyToInput(path);
#elif UNITY_STANDALONE_WIN
        var t = new Thread(() =>
        {
            var dlg = new System.Windows.Forms.OpenFileDialog { Filter = "MP3|*.mp3" };
            if (dlg.ShowDialog() == System.Windows.Forms.DialogResult.OK)
                _pendingFilePath = dlg.FileName;
        });
        t.SetApartmentState(ApartmentState.STA);
        t.Start();
#else
        SetAddStatus($"Copy file via ADB:\n{InputPath}");
#endif
    }

    private void CopyToInput(string srcPath)
    {
        try
        {
            string dest = Path.Combine(InputPath, Path.GetFileName(srcPath));
            File.Copy(srcPath, dest, overwrite: true);
            RefreshAudioList();
            string nameNoExt = Path.GetFileNameWithoutExtension(srcPath);
            int idx = audioFiles.FindIndex(f => Path.GetFileNameWithoutExtension(f) == nameNoExt);
            if (idx >= 0 && audioDropdown != null) audioDropdown.value = idx;
            SetAddStatus($"Added: {Path.GetFileName(srcPath)}");
        }
        catch (Exception e) { SetAddStatus($"File copy failed: {e.Message}"); }
    }

    private void OnUrlDownloadClicked()
    {
        string url = urlInput != null ? urlInput.text.Trim() : "";
        if (string.IsNullOrEmpty(url)) { SetAddStatus("Please enter a URL."); return; }

        if (!Uri.TryCreate(url, UriKind.Absolute, out var uri) ||
            (uri.Scheme != "http" && uri.Scheme != "https"))
        {
            SetAddStatus($"Invalid URL: must start with http:// or https://");
            return;
        }

        // Streaming service URLs cannot be downloaded directly
        string host = uri.Host.ToLower();
        if (host.Contains("youtube.com") || host.Contains("youtu.be") ||
            host.Contains("spotify.com") || host.Contains("soundcloud.com") ||
            host.Contains("music.apple.com"))
        {
            SetAddStatus("Streaming URLs not supported.\nUse a direct .mp3 download link or Browse File.");
            return;
        }

        StartCoroutine(DownloadFromUrl(uri.AbsoluteUri));
    }

    private IEnumerator DownloadFromUrl(string url)
    {
        SetAddStatus("Downloading...");
        if (urlDownloadBtn != null) urlDownloadBtn.interactable = false;
        ApplyButtonStyles();

        string fileName;
        try
        {
            string uriPath = new Uri(url).AbsolutePath;
            fileName = Path.GetFileName(uriPath);
            if (string.IsNullOrEmpty(fileName) || !fileName.EndsWith(".mp3", StringComparison.OrdinalIgnoreCase))
                fileName = "download.mp3";
        }
        catch { fileName = "download.mp3"; }

        string savePath = Path.GetFullPath(Path.Combine(InputPath, fileName));

        using var req = UnityWebRequest.Get(url);
        req.downloadHandler = new DownloadHandlerFile(savePath);
        yield return req.SendWebRequest();

        if (urlDownloadBtn != null) urlDownloadBtn.interactable = true;
        ApplyButtonStyles();

        if (req.result == UnityWebRequest.Result.Success)
        {
            RefreshAudioList();
            int idx = audioFiles.FindIndex(
                f => Path.GetFileNameWithoutExtension(f) == Path.GetFileNameWithoutExtension(fileName));
            if (idx >= 0 && audioDropdown != null) audioDropdown.value = idx;
            SetAddStatus($"Downloaded: {fileName}");
        }
        else
        {
            if (File.Exists(savePath)) File.Delete(savePath);
            SetAddStatus($"Download failed: {req.error}");
        }
    }

    private void SetAddStatus(string msg) { if (addStatusText != null) addStatusText.text = msg; }

    private void ApplyButtonStyles()
    {
        ApplyCreatorButtonStyle(generateButton, true);
        ApplyCreatorButtonStyle(urlDownloadBtn, true);
        ApplyCreatorButtonStyle(refreshBtn, false);
        ApplyCreatorButtonStyle(filePickerBtn, false);
        ApplyCreatorButtonStyle(backButton, false);
    }

    private static void ApplyCreatorButtonStyle(Button btn, bool primary)
    {
        if (btn == null)
            return;

        Color bg = btn.interactable ? (primary ? NeonBg : DarkButtonBg) : DisabledBg;
        if (btn.targetGraphic is Image img)
        {
            img.color = bg;
            img.raycastTarget = true;
        }

        var colors = btn.colors;
        colors.normalColor = bg;
        colors.highlightedColor = btn.interactable
            ? new Color(0.10f, 0.95f, 1.0f, primary ? 0.58f : 0.48f)
            : DisabledBg;
        colors.pressedColor = btn.interactable
            ? new Color(0.02f, 0.58f, 0.72f, 0.80f)
            : DisabledBg;
        colors.selectedColor = colors.highlightedColor;
        colors.disabledColor = DisabledBg;
        colors.fadeDuration = 0.08f;
        btn.colors = colors;

        TMP_Text label = btn.GetComponentInChildren<TMP_Text>(true);
        if (label != null)
        {
            label.color = btn.interactable ? ButtonText : MutedText;
            label.raycastTarget = false;
        }

        Outline outline = btn.GetComponent<Outline>() ?? btn.gameObject.AddComponent<Outline>();
        outline.enabled = btn.interactable;
        outline.effectColor = NeonOutline;
        outline.effectDistance = new Vector2(0.0f, -0.28f);
    }
}