/*
 * MIT License
 *
 * Copyright (c) 2024 Robert Myers
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

/**
 * @file SimpleProgressBar.h
 * 
 * @brief A simple progress bar for console applications.
 * 
 * @author Robert Myers
 * Contact: romyers@umich.edu
 */

 #pragma once

 #include <iostream>
 
 namespace SimpleProgressBar {
 
     /**
      * A simple progress bar for console applications.
      */
     class ProgressBar {
 
     public:
 
         /**
          * Constructor.
          * 
          * @param totalSteps The total number of progress bar steps.
          */
         ProgressBar(unsigned int totalSteps = 100U);
 
         /**
          * Increments the progress displayed by the progress bar by a given
          * number of steps (one by default).
          * 
          * If increment() brings the current progress above totalSteps,
          * the current progress will be snapped to totalSteps.
          * 
          * @param steps The number of steps by which to increment the displayed
          * progress.
          */
         void increment(unsigned int steps = 1U);
 
         /**
          * Retrieve the total number of steps in the progress bar.
          * 
          * @return The total number of steps
          */
         unsigned int getTotalSteps() const;
 
         /**
          * Prints the progress bar in its current state to a stream.
          * Prints to std::cout by default.
          * 
          * @param out The stream to print to.
          */
         void print(std::ostream &out = std::cout) const;
 
         /**
          * Sets the width of the progress bar display in number of characters.
          * The width of the progress bar is set to 80 characters by default.
          * 
          * REQUIRES: w is at least 2.
          * 
          * @param w The desired width of the progress bar, as a number of 
          * characters.
          */
         void setWidth(unsigned int w);
 
         /**
          * Sets the symbol for the progress bar's left endcap.
          * Set to '[' by default.
          * 
          * @param c The new symbol.
          */
         void setLeftEndcapSymbol(char c);
 
         /**
          * Sets the symbol for the progress bar's right endcap.
          * Set to ']' by default.
          * 
          * @param c The new symbol.
          */
         void setRightEndcapSymbol(char c);
 
         /**
          * Sets the symbol indicating completed progress.
          * Set to '=' by default.
          * 
          * @param c The new symbol.
          */
         void setDoneSymbol(char c);
 
         /**
          * Sets the symbol indicating progress that hasn't been completed yet.
          * Set to ' ' by default.
          */
         void setTodoSymbol(char c);
 
         /**
          * Sets the progress bar to overwrite the current output line on each
          * call to print(). This is equivalent to adding the '\r' character to
          * the end of the printed output.
          */
         void enableOverwrite();
 
         /**
          * Sets the progress bar not to overwrite the current output line on
          * each call to print(). Successive calls to print will be printed
          * one after another.
          */
         void disableOverwrite();
 
     private:
 
         unsigned int progress;
         unsigned int totalSteps;
 
         char leftEndcapSymbol;
         char rightEndcapSymbol;
         char doneSymbol;
         char todoSymbol;
 
         unsigned int width;
 
         bool overwrite;
 
     };
 
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 /////////////////////////////// IMPLEMENTATION ////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////////
 
 SimpleProgressBar::ProgressBar::ProgressBar(unsigned int totalSteps) : 
     progress(0),
     leftEndcapSymbol('['),
     rightEndcapSymbol(']'),
     doneSymbol('='),
     todoSymbol(' '),
     width(80U),
     overwrite(true),
     totalSteps(totalSteps) {}
 
 unsigned int SimpleProgressBar::ProgressBar::getTotalSteps() const {
 
     return totalSteps;
 
 }
 
 void SimpleProgressBar::ProgressBar::setLeftEndcapSymbol(char c) {
 
     leftEndcapSymbol = c;
 
 }
 
 void SimpleProgressBar::ProgressBar::setRightEndcapSymbol(char c) {
 
     rightEndcapSymbol = c;
 
 }
 
 void SimpleProgressBar::ProgressBar::setDoneSymbol(char c) {
 
     doneSymbol = c;
 
 }
 
 void SimpleProgressBar::ProgressBar::setTodoSymbol(char c) {
 
     todoSymbol = c;
 
 }
 
 void SimpleProgressBar::ProgressBar::setWidth(unsigned int w) {
 
     width = w;
 
 }
 
 void SimpleProgressBar::ProgressBar::increment(unsigned int steps) {
 
     progress += steps;
 
     if(progress > totalSteps) {
 
         progress = totalSteps;
 
     }
 
 }
 
 void SimpleProgressBar::ProgressBar::print(std::ostream &out) const {
 
     out << leftEndcapSymbol;
 
     double proportionalProgress = static_cast<double>(progress) 
                                 / static_cast<double>(totalSteps);
 
     // For nonnegative values, casting to int is equivalent to flooring.
     unsigned int numBarChars = static_cast<unsigned int>(
         proportionalProgress * (width - 2)
     );
 
     for(unsigned int w = 0; w < numBarChars; ++w) {
 
         out << doneSymbol;
     
     }
 
     for(unsigned int w = numBarChars; w < width - 2; ++w) {
 
         out << todoSymbol;
 
     }
 
     out << rightEndcapSymbol;
     out << std::flush;
     if(overwrite) out << '\r';
 
 }
 
 void SimpleProgressBar::ProgressBar::enableOverwrite() {
 
     overwrite = true;
 
 }
 
 void SimpleProgressBar::ProgressBar::disableOverwrite() {
 
     overwrite = false;
 
 }