#include "../include/GitRepository.hpp"
#include "../include/Dependency.hpp"
#include <git2.h>
#include <string>
#include <cassert>

using namespace std;

static bool libgitInitialized = false;

namespace sibs
{
    void gitInit()
    {
        if(!libgitInitialized)
        {
            libgitInitialized = true;
            // TODO: Call git_libgit2_shutdown in destructor? dont really need to do that though
            git_libgit2_init();
        }
    }
    
    Result<bool> buildGitError(int error, const string &errorPrefix)
    {
        const git_error *e = giterr_last();
        string errMsg = errorPrefix;
        errMsg += ": ";
        errMsg += to_string(error);
        errMsg += "/";
        errMsg += to_string(e->klass);
        errMsg += ": ";
        errMsg += e->message;
        return Result<bool>::Err(errMsg, error);
    }
    
    Result<bool> GitRepository::clone(GitDependency *gitDependency, const FileString &repoDirPath)
    {
        // TODO: Use git dependency revision when cloning
        gitInit();
        git_repository *repo;
        git_clone_options options = GIT_CLONE_OPTIONS_INIT;
        options.checkout_branch = gitDependency->branch.c_str();
        int error = git_clone(&repo, gitDependency->url.c_str(), toUtf8(repoDirPath).c_str(), &options);
        if(error != 0)
            return buildGitError(error, "Failed to clone git repository");
        
        git_repository_free(repo);
        return Result<bool>::Ok(true);
    }
    
    Result<bool> GitRepository::pull(GitDependency *gitDependency, const FileString &repoDirPath)
    {
        gitInit();
        int error;
        
        git_repository *repo;
        error = git_repository_open(&repo, toUtf8(repoDirPath).c_str());
        if(error != 0)
            return buildGitError(error, "Failed to open git repository");
        
        git_remote *remote;
        error = git_remote_lookup(&remote, repo, "origin");
        if(error != 0)
            return buildGitError(error, "Failed to do remote lookup for git repository");
        
        // TODO: Setup option to be able to use callback for progress (for output in console) and handling credentials
        error = git_remote_fetch(remote, NULL, NULL, "pull");
        if(error != 0)
        {
            Result<bool> err = buildGitError(error, "Failed to do remote fetch for git repository");
            git_remote_free(remote);
            git_repository_free(repo);
            return err;
        }
        
        git_reference *ref;
        error = git_reference_dwim(&ref, repo, gitDependency->branch.c_str());
        if(error != 0)
        {
            Result<bool> err = buildGitError(error, "Failed to do reference lookup for git repository");
            git_remote_free(remote);
            git_repository_free(repo);
            return err;
        }
        
        git_annotated_commit *annotatedCommit;
        error = git_annotated_commit_from_ref(&annotatedCommit, repo, ref);
        if(error != 0)
        {
            Result<bool> err = buildGitError(error, "Failed to get commit from ref");
            git_annotated_commit_free(annotatedCommit);
            git_remote_free(remote);
            git_repository_free(repo);
            return err;
        }
        
        assert(false);
        
        git_annotated_commit_free(annotatedCommit);
        git_remote_free(remote);
        git_repository_free(repo);
        return Result<bool>::Ok(true);
    }
}