#include "Noncanonical.h"

using namespace std;

// 全局终端设置
terminal_mode_t original_termios;
std::vector<std::string> cmdList{};


// 支持的命令列表
const vector<string> commands = {"setant", "seteph", "query","list", "exit", "help"};

void restore_terminal() {
#if defined(_WIN32)
	SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), original_termios);
#else
	tcsetattr(STDIN_FILENO, TCSANOW, &original_termios);
#endif
}

void set_noncanonical_mode() {
#if defined(_WIN32)
	HANDLE hStdin = GetStdHandle(STD_INPUT_HANDLE);
	GetConsoleMode(hStdin, &original_termios);
	
	DWORD new_mode = original_termios;
	new_mode &= ~ENABLE_ECHO_INPUT;    // 禁用回显
	new_mode &= ~ENABLE_LINE_INPUT;    // 禁用行缓冲
	new_mode &= ~ENABLE_PROCESSED_INPUT; // 禁用Ctrl+C处理
	
	SetConsoleMode(hStdin, new_mode);
#else
	struct termios new_termios;
    tcgetattr(STDIN_FILENO, &original_termios);
    new_termios = original_termios;
    
    new_termios.c_lflag &= ~(ICANON | ECHO | ISIG);
    new_termios.c_cc[VMIN] = 1;
    new_termios.c_cc[VTIME] = 0;
    
    tcsetattr(STDIN_FILENO, TCSANOW, &new_termios);
#endif
	
	atexit(restore_terminal);
}

string toLower(const string &str) {
	string result;
	for (char c : str) {
		result += tolower(c);
	}
	return result;
}
string tabCompletion(const string &currentLine, size_t cursorPos) {
    // 分割当前行
    vector<string> tokens;
    string token;
    for (char c: currentLine) {
        if (isspace(c)) {
            if (!token.empty()) {
                tokens.push_back(token);
                token.clear();
            }
        }
        else {
            token += c;
        }
    }
    if (!token.empty()) tokens.push_back(token);

    // 如果没有token或当前token为空
    if (tokens.empty() || token.empty()) return currentLine;

    bool isFirstToken = (tokens.size() == 1);
    string lastToken = tokens.back();

    // 候选列表
    vector<string> candidates;

    // 第一个token：匹配命令
    if (isFirstToken) {
        for (const string &cmd: commands) {
            if (cmd.substr(0, lastToken.size()) == lastToken) {
                candidates.push_back(cmd);
            }
        }
    }
//        // 第二个token：匹配键
//    else if (tokens.size() == 2) {
//        for (const auto &kv: kvStore) {
//            if (kv.first.substr(0, lastToken.size()) == lastToken) {
//                candidates.push_back(kv.first);
//            }
//        }
//    }

    // 没有候选结果
    if (candidates.empty()) {
//	    cout << "\n> " << currentLine << std::flush;
	    return currentLine;
    }

    // 唯一候选结果 - 直接补全
    if (candidates.size() == 1) {
        // 计算要删除的字符数
        size_t charsToErase = lastToken.size();

        // 创建新行
        string newLine = currentLine.substr(0, currentLine.size() - charsToErase);
        newLine += candidates[0];
        if (isFirstToken) newLine += " ";

        return newLine;
    }

    // 多个候选结果 - 打印选项
    cout << "\nPossible completions:\n";
    for (const auto &cand: candidates) {
        cout << "  " << cand << "\n";
    }
    cout << "> " << currentLine << std::flush;


    return currentLine;
}

string readLine(const string &prompt) {
	cout << prompt << flush;
	string line;
	static int historyIndex = -1;          // 当前历史命令索引
	static string tempLine = "";              // 临时保存当前编辑行

#if defined(_WIN32)
	while (true) {
		int ch = _getch(); // Windows专用字符读取
		
		// 处理特殊键
		if (ch == 0x00 || ch == 0xE0) {
			int ext = _getch(); // 获取扩展按键
			// 上方向键
			if (ext == 72) {
				if (!cmdList.empty()) {
					// 保存当前编辑行
					if (historyIndex == -1) tempLine = line;
					
					// 更新历史索引
					if (historyIndex < cmdList.size() - 1)
						historyIndex++;
					else if (historyIndex == -1)
						historyIndex = 0;
					
					//清除
					cout << "\r" << prompt << string(line.size(), ' ') << flush;
					
					// 更新当前行
					line = cmdList[cmdList.size() - 1 - historyIndex];
					
					//重绘
					cout << "\r" << prompt << line << flush;
				}
				continue;
			}
				// 下方向键
			else if (ext == 80) {
				if (historyIndex != -1) {
					//清除
					cout << "\r" << prompt << string(line.size(), ' ') << flush;
					if (historyIndex > 0) {
						historyIndex--;
						line = cmdList[cmdList.size() - 1 - historyIndex];
					}
					else {
						historyIndex = -1;
						line = tempLine;
					}
					
					//重绘
					cout << "\r" << prompt << line << flush;
				}
				continue;
			}
		}
		
		switch (ch) {
			case '\r': // Enter键
				cout << endl;
				return line;
			
			case '\t': // Tab键
				line = tabCompletion(line, line.size());
				cout << "\r" << prompt << string(line.size(), ' ') << flush;
				cout << "\r" << prompt << line << flush;
				break;
			
			case 8: // Backspace键
				if (!line.empty()) {
					line.pop_back();
					cout << "\b \b" << flush;
				}
				break;
			
			case 3: // Ctrl+C
				cout << endl;
				exit(0);
				break;
			
			default: // 可打印字符
				if (isprint(ch)) {
					line += ch;
					cout << static_cast<char>(ch) << flush;
				}
		}
	}
#else
    char ch;

    while (read(STDIN_FILENO, &ch, 1) == 1) {
		// 处理方向键序列 (ESC [ A 或 ESC [ B)
        if (ch == 27) { // ESC
            char seq[2];
            if (read(STDIN_FILENO, seq, 2) == 2) {
                // 上方向键
                if (seq[0] == '[' && seq[1] == 'A') {
                    if (!cmdList.empty()) {
                        // 保存当前编辑行
                        if (historyIndex == -1) tempLine = line;
                        
                        // 更新历史索引
                        if (historyIndex < cmdList.size() - 1)
                            historyIndex++;
                        else if (historyIndex == -1)
                            historyIndex = 0;

                        for (size_t i = 0; i < line.size(); i++) cout << "\b \b";
                        
                        // 更新当前行
                        line = cmdList[cmdList.size() - 1 - historyIndex];
                        
                        // 清除并重绘

                        cout << line << flush;
                    }
                    continue;
                }
                // 下方向键
                else if (seq[0] == '[' && seq[1] == 'B') {
                    if (historyIndex != -1) {
                        for (size_t i = 0; i < line.size(); i++) cout << "\b \b";
                        if (historyIndex > 0) {
                            historyIndex--;
                            line = cmdList[cmdList .size() - 1 - historyIndex];
                        } else {
                            historyIndex = -1;
                            line = tempLine;
                        }
                        
                        // 清除并重绘
                        cout << line << flush;
                    }
                    continue;
                }
            }
        }
        // Enter键 - 完成输入
        if (ch == '\n') {
            cout << endl;
            return line;
        }

        // Tab键 - 触发补全
        if (ch == '\t') {
            string newLine = tabCompletion(line, line.size());
            if (newLine != line) {
                // 清除当前行
                for (size_t i = 0; i < line.size(); i++) {
                    cout << "\b \b";
                }

                line = newLine;
                cout << line << flush;
            }
            continue;
        }

        // Backspace键 - 删除字符（支持不同终端的两种编码）
        if (ch == 127 || ch == 8) {
            if (!line.empty()) {
                line.pop_back();
                // 清除字符：\b 移动光标，空格覆盖字符，再\b移动光标
                cout << "\b \b" << flush;
            }
            continue;
        }

        // Ctrl+C - 退出程序
        if (ch == 3) {
            cout << endl;
            exit(0);
        }

        // 其他可打印字符
        if (isprint(ch)) {
            line += ch;
            cout << ch << flush;
        }
    }
#endif
    return line;
}