#include "switchchain.hpp"
#include "exports.hpp"
#include "graph.hpp"
#include "graph_ccm.hpp"
#include "graph_spectrum.hpp"
#include "graph_powerlaw.hpp"
#include <algorithm>
#include <array>
#include <fstream>
#include <iostream>
#include <numeric>
#include <random>
#include <vector>

int main(int argc, char* argv[]) {
    // Simulation parameters
    const int numVerticesMin = 100;
    const int numVerticesMax = 500;
    const int numVerticesStep = 100;

    float tauValues[] = {2.1f, 2.2f, 2.3f, 2.4f, 2.5f, 2.6f, 2.7f, 2.8f, 2.9f};

    const int totalDegreeSamples = 5;

    auto getMixingTime = [](int n, float tau) {
        return int(30.0f * (50.0f - 30.0f * (tau - 2.0f)) * n);
    };
    constexpr int measurements = 50;
    constexpr int measureSkip = 200; // Take a sample every ... steps

    // Output file
    std::ofstream outfile;
    if (argc >= 2)
        outfile.open(argv[1]);
    else
        outfile.open("graphdata_spectrum.m");
    if (!outfile.is_open()) {
        std::cout << "ERROR: Could not open output file.\n";
        return 1;
    }

    // Output Mathematica-style comment to indicate file contents
    outfile << "(*\n";
    outfile << "n from " << numVerticesMin << " to " << numVerticesMax
            << " step " << numVerticesStep << std::endl;
    outfile << "tauValues: " << tauValues << std::endl;
    outfile << "degreeSamples: " << totalDegreeSamples << std::endl;
    outfile << "mixingTime: 30 * (50 - 30 (tau - 2)) n\n";
    outfile << "data:\n";
    outfile << "1: {n,tau}\n";
    outfile << "2: triangleSeq\n";
    outfile << "3: edges\n";
    outfile << "4: start adj spectrum\n";
    outfile << "5: start laplacian spectrum\n";
    outfile << "6: end adj spectrum\n";
    outfile << "7: end laplacian spectrum\n";
    outfile << "*)" << std::endl;

    // Mathematica does not accept things of the form 1.23e-5
    // (instead it would write that as 1.23*^-5)
    // so simply use normal notation up to 6 decimals
    outfile << std::fixed;

    outfile << '{';
    bool outputComma = false;

    std::mt19937 rng(std::random_device{}());
    Graph g;
    for (int numVertices = numVerticesMin; numVertices <= numVerticesMax;
         numVertices += numVerticesStep) {
        for (float tau : tauValues) {
            // For a single n,tau take samples over several instances of
            // the degree distribution.
            for (int degreeSample = 0; degreeSample < totalDegreeSamples;
                 ++degreeSample) {
                DegreeSequence ds;
                generatePowerlawGraph(numVertices, tau, g, ds, rng);

                SwitchChain chain;
                if (!chain.initialize(g)) {
                    std::cerr << "Could not initialize Markov chain.\n";
                    return 1;
                }

                std::cout << "Running n = " << numVertices << ", tau = " << tau
                          << ". \t" << std::flush;

                int mixingTime = getMixingTime(numVertices,tau);;

                int movesTotal = 0;
                int movesSuccess = 0;

                int triangles[measurements];

                for (int i = 0; i < mixingTime; ++i) {
                    ++movesTotal;
                    if (chain.doMove()) {
                        ++movesSuccess;
                    }
                }

                for (int i = 0; i < measurements; ++i) {
                    for (int j = 0; j < measureSkip; ++j) {
                        ++movesTotal;
                        if (chain.doMove()) {
                            ++movesSuccess;
                        }
                    }
                    triangles[i] = chain.g.countTriangles();
                }

                std::cout << '('
                          << 100.0f * float(movesSuccess) / float(movesTotal)
                          << "% successrate). " << std::flush;
                // std::cout << std::endl;

                GraphSpectrum gs_start(g);
                GraphSpectrum gs_end(chain.g);

                if (outputComma)
                    outfile << ',' << '\n';
                outputComma = true;

                //std::sort(ds.begin(), ds.end());
                outfile << '{' << '{' << numVertices << ',' << tau << '}';
                outfile << ',' << triangles;
                outfile << ',' << g.edgeCount();
                outfile << ',' << gs_start.computeAdjacencySpectrum();
                outfile << ',' << gs_start.computeLaplacianSpectrum();
                outfile << ',' << gs_end.computeAdjacencySpectrum();
                outfile << ',' << gs_end.computeLaplacianSpectrum();
                outfile << '}' << std::flush;

                std::cout << std::endl;
            }
        }
    }
    outfile << '}';
    return 0;
}