using static Game.I18n;
using System.Runtime.InteropServices;
using System.Text;

namespace Game.UI {
    public class TextDisplay {
        private const string RGB_FG_SEQ_START = "\e[38;2;";
        private const string RGB_BG_SEQ_START = "\e[48;2;";
        private const string ESC_SEQ_START = "\e[";
        private const string SETCURSOR_END = "H";
        private const string GRAPHICS_SEQ_END = "m";
        private const string HIDECURSOR_SEQ = "\e[?25l";
        private const string SHOWCURSOR_SEQ = "\e[?25h";

        private readonly char[] SIMPLE_BOX_CHARS = { '─', '│', '┌', '┐', '└', '┘' };
        private readonly char[] DOUBLE_BOX_CHARS = { '═', '║', '╔', '╗', '╚', '╝' };
        private readonly char[] FALLBACK_BOX_CHARS = { '-', '|', '+', '+', '+', '+' };

        private int currentFgColor = 0xffffff, currentBgColor = 0;
        private int cursorRow = 0, cursorCol = 0;
        private int windowWidth = 0, windowHeight = 0;

        public bool InitWindow() {
            if (Console.IsOutputRedirected) {
                Console.WriteLine(GetMessage(Message.OUTPUT_IS_NOT_TERMINAL));
                return false;
            }
            Console.InputEncoding = Encoding.UTF8;
            Console.OutputEncoding = Encoding.UTF8;

            IntPtr consoleInHandle = Win32Imports.GetStdHandle(Win32Imports.STD_INPUT_HANDLE);
            IntPtr consoleOutHandle = Win32Imports.GetStdHandle(Win32Imports.STD_OUTPUT_HANDLE);

            uint inConsoleMode, outConsoleMode;
            if (!Win32Imports.GetConsoleMode(consoleInHandle, out inConsoleMode)) {
                Console.WriteLine(GetMessage(Message.ERROR_GETCONSOLEMODE));
                return false;
            }
            if (!Win32Imports.GetConsoleMode(consoleOutHandle, out outConsoleMode)) {
                Console.WriteLine(GetMessage(Message.ERROR_GETCONSOLEMODE));
                return false;
            }
            inConsoleMode |= Win32Imports.ENABLE_VIRTUAL_TERMINAL_INPUT;
            //inConsoleMode &= ~Win32Imports.ENABLE_LINE_INPUT;
            outConsoleMode |= Win32Imports.ENABLE_VIRTUAL_TERMINAL_PROCESSING;
            if (!Win32Imports.SetConsoleMode(consoleInHandle, inConsoleMode)) {
                Console.WriteLine(GetMessage(Message.ERROR_SETCONSOLEMODE));
                return false;
            }
            if (!Win32Imports.SetConsoleMode(consoleOutHandle, outConsoleMode)) {
                Console.WriteLine(GetMessage(Message.ERROR_SETCONSOLEMODE));
                return false;
            }
            SetColors(currentFgColor, currentBgColor);
            HideCursor();
            SetCursor(cursorRow, cursorCol);
            windowWidth = Console.BufferWidth;
            windowHeight = Console.BufferHeight;
            return true;
        }

        public void ResetWindow() {
            SetColors(0xffffff, 0);
            SetCursor(1, 1);
            ShowCursor();
        }

        public void PrintSimpleWelcome() {
            WriteColored("Welcome to КТО ХОЧЕТ СТАТЬ СЕКУНДОМЕРОМ", 0x5e61ed);
        }

        public void ShowSplash() {
            ClearWithColor(0x5e61ed);

            DrawTitle(windowHeight / 2 + 1 - 3, 0x5e61ed);
            DrawCopyright(0x5e61ed);
        }

        public void ShowFatalError(string text) {
            ClearWithColor(0xfc5d2d);
            DrawTextBox(HAlignment.Center, VAlignment.Center, BoxType.Double, windowHeight / 2 + 1, windowWidth / 2 + 1, text, 0xffffff, 0xffffff, 0xfc5d2d, windowWidth / 2);
        }

        void DrawTitle(int y, int bgColor) {
            string text1 = "КТО ХОЧЕТ СТАТЬ";
            string text2 = "СЕКУНДОМЕРОМ";
            SetColors(0xffffff, 0);

            int text1Start = (windowWidth - text1.Length) / 2 + 1;
            SetCursor(y, text1Start - 6);
            for (int i = 0; i < 6; ++i) {
                WriteColored(" ", -1, ColorBlend(0, bgColor, (float)i / 6));
            }
            WriteColored(text1, 0xffffff, 0);
            for (int i = 6; i >= 0; --i) {
                WriteColored(" ", -1, ColorBlend(0, bgColor, (float)i / 6));
            }

            int text2Start = (windowWidth - text2.Length) / 2 + 1;
            SetCursor(y + 2, text2Start - 6);
            for (int i = 0; i < 6; ++i) {
                WriteColored(" ", -1, ColorBlend(0, bgColor, (float)i / 6));
            }
            WriteColored(text2, 0xffffff, 0);
            for (int i = 6; i >= 0; --i) {
                WriteColored(" ", -1, ColorBlend(0, bgColor, (float)i / 6));
            }
        }

        void DrawCopyright(int bgColor) {
            string bottomText = "(c) subvia, 2025";
            SetCursor(windowHeight, (windowWidth - bottomText.Length) / 2 + 1);
            WriteColored(bottomText, 0x4d4dc0, bgColor);
        }

        void DrawTextBox(HAlignment hAlign, VAlignment vAlign, BoxType boxType, int y, int x, string text, int borderColor, int textColor, int bgColor = -1, int preferredWidth = -1) {
            int maxWidth = windowWidth;
            switch (hAlign) {
                case HAlignment.Left:
                    maxWidth = windowWidth - x + 1;
                    break;
                case HAlignment.Center:
                    maxWidth = Math.Min(x - 1, windowWidth - x + 1) * 2;
                    break;
                case HAlignment.Right:
                    maxWidth = x - 1;
                    break;
            }
            int maxHeight = windowHeight;
            switch (vAlign) {
                case VAlignment.Top:
                    maxHeight = windowHeight - y + 1;
                    break;
                case VAlignment.Center:
                    maxHeight = Math.Min(y - 1, windowHeight - y + 1) * 2;
                    break;
                case VAlignment.Bottom:
                    maxHeight = y - 1;
                    break;
            }
            string[] lines = WordWrap(text, (preferredWidth == -1 ? maxWidth : preferredWidth) - 4, out bool overflow);
            bool reflowed = false;
            if (preferredWidth != -1 && lines.Length > maxHeight - 4) {
                reflowed = true;
                lines = WordWrap(text, maxWidth - 4, out overflow);
            }
            int actualWidth = Math.Min(preferredWidth == -1 ? maxWidth : (reflowed ? maxWidth : preferredWidth), lines.Max(s => s.Length) + 4);
            int actualHeight = Math.Min(maxHeight, lines.Length + 4);

            int left = hAlign == HAlignment.Left ? x : (hAlign == HAlignment.Right ? x - actualWidth + 1 : x - (actualWidth - 1) / 2);
            int top = vAlign == VAlignment.Top ? y : (vAlign == VAlignment.Bottom ? y - actualHeight + 1 : y - (actualHeight - 1) / 2);
            DrawBox(boxType, top, left, actualHeight, actualWidth, borderColor, bgColor);
            SetColors(textColor, -1);
            for (int i = 0; i < actualHeight - 4; ++i) {
                SetCursor(top + 2 + i, left + 2);
                WriteColored(lines[i], textColor, bgColor);
            }
        }

        public void DrawBox(BoxType boxType, int y, int x, int h, int w, int borderColor, int bgColor = -1) {
            char[] boxChars = boxType == BoxType.Simple ? SIMPLE_BOX_CHARS : (boxType == BoxType.Double ? DOUBLE_BOX_CHARS : FALLBACK_BOX_CHARS);
            SetColors(borderColor, bgColor);
            SetCursor(y, x);
            StringBuilder output = new StringBuilder();
            output.Append(boxChars[2]);
            output.Append(boxChars[0], w - 2);
            output.Append(boxChars[3]);
            WriteColored(output.ToString(), borderColor, bgColor);
            for (int i = 0; i < h - 2; ++i) {
                output.Clear();
                SetCursor(y + 1 + i, x);
                output.Append(boxChars[1]);
                output.Append(' ', w - 2);
                output.Append(boxChars[1]);
                WriteColored(output.ToString(), borderColor, bgColor);
            }
            SetCursor(y + h - 1, x);
            output.Clear();
            output.Append(boxChars[4]);
            output.Append(boxChars[0], w - 2);
            output.Append(boxChars[5]);
            WriteColored(output.ToString(), borderColor, bgColor);
        }

        public void WriteColored(string s, int color, int bgColor = -1) {
            if (color == -1) color = currentFgColor;
            (int r, int g, int b) = ((color >> 16) & 255, (color >> 8) & 255, color & 255);
            currentFgColor = color;
            if (bgColor == -1) {
                Console.Write(RGB_FG_SEQ_START + r + ';' + g + ';' + b + GRAPHICS_SEQ_END + s);
            } else {
                (int br, int bg, int bb) = ((bgColor >> 16) & 255, (bgColor >> 8) & 255, bgColor & 255);
                Console.Write(RGB_FG_SEQ_START + r + ';' + g + ';' + b + GRAPHICS_SEQ_END + RGB_BG_SEQ_START + br + ';' + bg + ';' + bb + GRAPHICS_SEQ_END + s);
                currentBgColor = bgColor;
            }
        }

        public void SetColors(int fg, int bg) {
            StringBuilder command = new StringBuilder();
            if (fg != -1) {
                (int r, int g, int b) = ((fg >> 16) & 255, (fg >> 8) & 255, fg & 255);
                command.Append(RGB_FG_SEQ_START + r + ';' + g + ';' + b + GRAPHICS_SEQ_END);
            }
            if (bg != -1) {
                (int r, int g, int b) = ((bg >> 16) & 255, (bg >> 8) & 255, bg & 255);
                command.Append(RGB_BG_SEQ_START + r + ';' + g + ';' + b + GRAPHICS_SEQ_END);
            }
            Console.Write(command.ToString());
        }

        public void ClearWithColor(int color) {
            (int r, int g, int b) = ((color >> 16) & 255, (color >> 8) & 255, color & 255);
            SetColors(-1, color);
            Console.Write("\e[2J");
        }

        public void SetCursor(int row, int column) {
            Console.Write(ESC_SEQ_START + row + ';' + column + SETCURSOR_END);
        }

        public void HideCursor() {
            Console.Write(HIDECURSOR_SEQ);
        }

        public void ShowCursor() {
            Console.Write(SHOWCURSOR_SEQ);
        }

        public int ColorBlend(int fg, int bg, float alpha) {
            //return (int)(fg * alpha + bg * (1f - alpha));
            return ((int)(((fg >> 16) & 255) * alpha + ((bg >> 16) & 255) * (1 - alpha)) << 16) + ((int)(((fg >> 8) & 255) * alpha + ((bg >> 8) & 255) * (1 - alpha)) << 8) + (int)((fg & 255) * alpha + (bg & 255) * (1 - alpha));
        }

        public string[] WordWrap(string text, int width, out bool overflow) {
            overflow = false;
            List<string> lines = new List<string>();
            StringBuilder line = new StringBuilder(text.Length / width * 4 / 3);
            int remaining = width;
            foreach (string word in text.Split(new char[] {' ', '\n'}, StringSplitOptions.RemoveEmptyEntries)) {
                if (word.Length <= remaining) {
                    if (line.Length == 0 || line[^1] != ' ') {
                        line.Append(' ');
                        remaining -= 1;
                    }
                    line.Append(word);
                    remaining -= word.Length;
                } else {
                    lines.Add(line.ToString());
                    line.Clear();
                    line.Append(word);
                    remaining = width - word.Length;
                    if (remaining < 0) {
                        overflow = true;
                        line.Remove(width + 1, line.Length - (width + 1));
                        lines.Add(line.ToString());
                        line.Clear();
                    }
                }
            }
            if (line.Length > 0)
                lines.Add(line.ToString());
            return lines.ToArray();
        }

        public enum HAlignment {
            Left, Center, Right
        }

        public enum VAlignment {
            Top, Center, Bottom
        }

        public enum BoxType {
            Simple,
            Double,
            Fallback,
        }
    }

    static class Win32Imports
    {
        public const int STD_INPUT_HANDLE = -10;
        public const int STD_OUTPUT_HANDLE = -11;
        public const uint ENABLE_VIRTUAL_TERMINAL_PROCESSING = 4;
        public const uint ENABLE_LINE_INPUT = 2;
        public const uint ENABLE_VIRTUAL_TERMINAL_INPUT = 512;

        [DllImport("kernel32.dll", SetLastError = true)]
        public static extern IntPtr GetStdHandle(int stdHandle);
        [DllImport("kernel32.dll")]
        public static extern bool SetConsoleMode(IntPtr consoleHandle, uint mode);
        [DllImport("kernel32.dll")]
        public static extern bool GetConsoleMode(IntPtr consoleHandle, out uint mode);
    }
}