using System;
using System.Collections.Generic;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Windows.Forms;
using PKHeX.Core;
using static PKHeX.Core.MessageStrings;

namespace PKHeX.WinForms
{
    public partial class BatchEditor : Form
    {
        private readonly SaveFile SAV;
        private readonly PKM pkm;
        private int currentFormat = -1;

        public BatchEditor(PKM pk, SaveFile sav)
        {
            InitializeComponent();
            WinFormsUtil.TranslateInterface(this, Main.CurrentLanguage);
            pkm = pk;
            SAV = sav;
            DragDrop += TabMain_DragDrop;
            DragEnter += TabMain_DragEnter;

            CB_Format.Items.Clear();
            CB_Format.Items.Add(MsgAny);
            foreach (Type t in BatchEditing.Types)
                CB_Format.Items.Add(t.Name.ToLowerInvariant());
            CB_Format.Items.Add(MsgAll);

            CB_Format.SelectedIndex = CB_Require.SelectedIndex = 0;
            toolTip1.SetToolTip(CB_Property, MsgBEToolTipPropName);
            toolTip2.SetToolTip(L_PropType, MsgBEToolTipPropType);
            toolTip3.SetToolTip(L_PropValue, MsgBEToolTipPropValue);
        }

        private void B_Open_Click(object sender, EventArgs e)
        {
            if (!B_Go.Enabled) return;
            using var fbd = new FolderBrowserDialog();
            if (fbd.ShowDialog() != DialogResult.OK)
                return;

            TB_Folder.Text = fbd.SelectedPath;
            TB_Folder.Visible = true;
        }

        private void B_SAV_Click(object sender, EventArgs e)
        {
            TB_Folder.Text = string.Empty;
            TB_Folder.Visible = false;
        }

        private void B_Go_Click(object sender, EventArgs e)
        {
            RunBackgroundWorker();
        }

        private void B_Add_Click(object sender, EventArgs e)
        {
            if (CB_Property.SelectedIndex < 0)
            { WinFormsUtil.Alert(MsgBEPropertyInvalid); return; }

            var prefix = StringInstruction.Prefixes;
            string s = prefix[CB_Require.SelectedIndex] + CB_Property.Items[CB_Property.SelectedIndex].ToString() + StringInstruction.SplitInstruction;
            if (RTB_Instructions.Lines.Length != 0 && RTB_Instructions.Lines[^1].Length > 0)
                s = Environment.NewLine + s;

            RTB_Instructions.AppendText(s);
        }

        private void CB_Format_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (currentFormat == CB_Format.SelectedIndex)
                return;

            int format = CB_Format.SelectedIndex;
            CB_Property.Items.Clear();
            CB_Property.Items.AddRange(BatchEditing.Properties[format]);
            CB_Property.SelectedIndex = 0;
            currentFormat = format;
        }

        private void CB_Property_SelectedIndexChanged(object sender, EventArgs e)
        {
            L_PropType.Text = BatchEditing.GetPropertyType(CB_Property.Text, CB_Format.SelectedIndex);
            if (BatchEditing.TryGetHasProperty(pkm, CB_Property.Text, out var pi))
            {
                L_PropValue.Text = pi.GetValue(pkm)?.ToString();
                L_PropType.ForeColor = L_PropValue.ForeColor; // reset color
            }
            else // no property, flag
            {
                L_PropValue.Text = string.Empty;
                L_PropType.ForeColor = Color.Red;
            }
        }

        private static void TabMain_DragEnter(object? sender, DragEventArgs? e)
        {
            if (e?.Data is null)
                return;
            if (e.Data.GetDataPresent(DataFormats.FileDrop))
                e.Effect = DragDropEffects.Copy;
        }

        private void TabMain_DragDrop(object? sender, DragEventArgs? e)
        {
            if (e?.Data?.GetData(DataFormats.FileDrop) is not string[] {Length: not 0} files)
                return;
            if (!Directory.Exists(files[0]))
                return;

            TB_Folder.Text = files[0];
            TB_Folder.Visible = true;
            RB_Boxes.Checked = RB_Party.Checked = false;
            RB_Path.Checked = true;
        }

        private void RunBackgroundWorker()
        {
            if (RTB_Instructions.Lines.Any(line => line.Length == 0))
            { WinFormsUtil.Error(MsgBEInstructionInvalid); return; }

            var sets = StringInstructionSet.GetBatchSets(RTB_Instructions.Lines).ToArray();
            if (sets.Any(s => s.Filters.Any(z => string.IsNullOrWhiteSpace(z.PropertyValue))))
            { WinFormsUtil.Error(MsgBEFilterEmpty); return; }

            if (sets.Any(z => z.Instructions.Count == 0))
            { WinFormsUtil.Error(MsgBEInstructionNone); return; }

            var emptyVal = sets.SelectMany(s => s.Instructions.Where(z => string.IsNullOrWhiteSpace(z.PropertyValue))).ToArray();
            if (emptyVal.Length > 0)
            {
                string props = string.Join(", ", emptyVal.Select(z => z.PropertyName));
                string invalid = MsgBEPropertyEmpty + Environment.NewLine + props;
                if (DialogResult.Yes != WinFormsUtil.Prompt(MessageBoxButtons.YesNo, invalid, MsgContinue))
                    return;
            }

            string? destPath = null;
            if (RB_Path.Checked)
            {
                WinFormsUtil.Alert(MsgExportFolder, MsgExportFolderAdvice);
                using var fbd = new FolderBrowserDialog();
                var dr = fbd.ShowDialog();
                if (dr != DialogResult.OK)
                    return;

                destPath = fbd.SelectedPath;
            }

            FLP_RB.Enabled = RTB_Instructions.Enabled = B_Go.Enabled = false;

            foreach (var set in sets)
            {
                BatchEditing.ScreenStrings(set.Filters);
                BatchEditing.ScreenStrings(set.Instructions);
            }
            RunBatchEdit(sets, TB_Folder.Text, destPath);
        }

        private void RunBatchEdit(StringInstructionSet[] sets, string source, string? destination)
        {
            editor = new Core.BatchEditor();
            bool finished = false, displayed = false; // hack cuz DoWork event isn't cleared after completion
            b.DoWork += (sender, e) =>
            {
                if (finished)
                    return;
                if (RB_Boxes.Checked)
                    RunBatchEditSaveFile(sets, boxes: true);
                else if (RB_Party.Checked)
                    RunBatchEditSaveFile(sets, party: true);
                else if (destination != null)
                    RunBatchEditFolder(sets, source, destination);
                finished = true;
            };
            b.ProgressChanged += (sender, e) => SetProgressBar(e.ProgressPercentage);
            b.RunWorkerCompleted += (sender, e) =>
            {
                string result = editor.GetEditorResults(sets);
                if (!displayed) WinFormsUtil.Alert(result);
                displayed = true;
                FLP_RB.Enabled = RTB_Instructions.Enabled = B_Go.Enabled = true;
                SetupProgressBar(0);
            };
            b.RunWorkerAsync();
        }

        private void RunBatchEditFolder(IReadOnlyCollection<StringInstructionSet> sets, string source, string destination)
        {
            var files = Directory.GetFiles(source, "*", SearchOption.AllDirectories);
            SetupProgressBar(files.Length * sets.Count);
            foreach (var set in sets)
                ProcessFolder(files, destination, set.Filters, set.Instructions);
        }

        private void RunBatchEditSaveFile(IReadOnlyCollection<StringInstructionSet> sets, bool boxes = false, bool party = false)
        {
            var data = new List<SlotCache>();
            if (party)
            {
                SlotInfoLoader.AddPartyData(SAV, data);
                process(data);
                SAV.PartyData = data.ConvertAll(z => z.Entity);
            }
            if (boxes)
            {
                SlotInfoLoader.AddBoxData(SAV, data);
                process(data);
                SAV.BoxData = data.ConvertAll(z => z.Entity);
            }
            void process(IList<SlotCache> d)
            {
                SetupProgressBar(d.Count * sets.Count);
                foreach (var set in sets)
                    ProcessSAV(d, set.Filters, set.Instructions);
            }
        }

        // Progress Bar
        private void SetupProgressBar(int count)
        {
            MethodInvoker mi = () => { PB_Show.Minimum = 0; PB_Show.Step = 1; PB_Show.Value = 0; PB_Show.Maximum = count; };
            if (PB_Show.InvokeRequired)
                PB_Show.Invoke(mi);
            else
                mi.Invoke();
        }

        private void SetProgressBar(int position)
        {
            if (PB_Show.InvokeRequired)
                PB_Show.Invoke((MethodInvoker)(() => PB_Show.Value = position));
            else
                PB_Show.Value = position;
        }

        // Mass Editing
        private Core.BatchEditor editor = new();

        private void ProcessSAV(IList<SlotCache> data, IReadOnlyList<StringInstruction> Filters, IReadOnlyList<StringInstruction> Instructions)
        {
            if (data.Count == 0)
                return;

            var filterMeta = Filters.Where(f => BatchFilters.FilterMeta.Any(z => z.IsMatch(f.PropertyName))).ToArray();
            if (filterMeta.Length != 0)
                Filters = Filters.Except(filterMeta).ToArray();

            var max = data[0].Entity.MaxSpeciesID;

            for (int i = 0; i < data.Count; i++)
            {
                var entry = data[i];
                var pk = data[i].Entity;

                var spec = pk.Species;
                if (spec <= 0 || spec > max)
                    continue;

                if (entry.Source is SlotInfoBox info && SAV.GetSlotFlags(info.Box, info.Slot).IsOverwriteProtected())
                    editor.AddSkipped();
                else if (!BatchEditing.IsFilterMatchMeta(filterMeta, entry))
                    editor.AddSkipped();
                else
                    editor.Process(pk, Filters, Instructions);

                b.ReportProgress(i);
            }
        }

        private void ProcessFolder(IReadOnlyList<string> files, string destDir, IReadOnlyList<StringInstruction> pkFilters, IReadOnlyList<StringInstruction> instructions)
        {
            var filterMeta = pkFilters.Where(f => BatchFilters.FilterMeta.Any(z => z.IsMatch(f.PropertyName))).ToArray();
            if (filterMeta.Length != 0)
                pkFilters = pkFilters.Except(filterMeta).ToArray();

            for (int i = 0; i < files.Count; i++)
            {
                TryProcess(files[i], destDir, filterMeta, pkFilters, instructions);
                b.ReportProgress(i);
            }
        }

        private void TryProcess(string source, string destDir, IReadOnlyList<StringInstruction> metaFilters, IReadOnlyList<StringInstruction> pkFilters, IReadOnlyList<StringInstruction> instructions)
        {
            var fi = new FileInfo(source);
            if (!EntityDetection.IsSizePlausible(fi.Length))
                return;

            byte[] data = File.ReadAllBytes(source);
            _ = FileUtil.TryGetPKM(data, out var pk, fi.Extension, SAV);
            if (pk == null)
                return;

            var info = new SlotInfoFile(source);
            var entry = new SlotCache(info, pk);
            if (!BatchEditing.IsFilterMatchMeta(metaFilters, entry))
            {
                editor.AddSkipped();
                return;
            }

            if (editor.Process(pk, pkFilters, instructions))
                File.WriteAllBytes(Path.Combine(destDir, Path.GetFileName(source)), pk.DecryptedPartyData);
        }
    }
}