#include <Core/Core.h>
#include <ide/Core/Core.h>
#include <sys/inotify.h>

using namespace Upp;

void GatherAllFiles(const String& path, Index<String>& filei, VectorMap<String, String>& file)
{
    Sleep(0); // This is supposed to be superlazy
    for(FindFile ff(path + "/*.*"); ff && !Thread::IsShutdownThreads(); ff.Next())
        if(ff.IsFolder() && *ff.GetName() != '.')
            GatherAllFiles(ff.GetPath(), filei, file);
        else
        if(ff.IsFile()) {
            String p = NormalizePath(ff.GetPath());
            String lp = ToLower(p);
            if(filei.Find(lp) < 0) {
                filei.Add(lp);
                file.Add(GetFileName(p), p);
            }
        }
}

class INotify {
    int           fd          {};
    Index<String> directories {};
    Buffer<char>  buffer      {};
    Index<int>    watches     {};
    
    const int BUFFER_SIZE = 4096;
    
    Vector<String> add;
    Vector<String> remove;
    
public:
    void AddWatch(String directory) {
        add.Add(directory);
        
        if(directories.Find(directory) < 0) {
            auto wd = inotify_add_watch(fd, directory, IN_CREATE | IN_DELETE | IN_DELETE_SELF | IN_MOVED_TO | IN_MOVED_FROM | IN_CLOSE_WRITE);
            
            if(wd == -1) {
                LOG("watch failed!");
                return;
            }
            
            directories.Add(directory);
            watches.Add(wd);
        }
    }
    
    void AddWatchRecursive(String path) {
        AddWatch(path);
        
        for(FindFile ff(path + "/*.*"); ff && !Thread::IsShutdownThreads(); ff.Next()) {
            if(ff.IsFolder() && *ff.GetName() != '.') {
                AddWatchRecursive(ff.GetPath());
            }
        }
    }
    
    void RemoveWatch(String directory) {
        auto idx = directories.Find(directory);
        
        if(idx >= 0) {
            inotify_rm_watch(fd, watches[idx]);
            directories.Unlink(idx);
            watches.Unlink(idx);
        }
    }
    
    void Run() {
        const size_t EVENT_SIZE     = ( sizeof (struct inotify_event) );
        const size_t EVENT_BUF_LEN  = ( 1024 * ( EVENT_SIZE + 16 ) );
        
        ssize_t numBytes = read(fd, buffer.begin(), BUFFER_SIZE);
        
        if(numBytes == -1 && errno != EAGAIN) {
            LOG("read failed!");
        }
        
        struct inotify_event* event = reinterpret_cast<struct inotify_event*>(buffer.begin());
        
        int i = 0;
        
        while(i < numBytes) {
            struct inotify_event *event = ( struct inotify_event * ) &buffer[i];
            
            auto idx = watches.Find(event->wd);
            
            if(idx < 0) break;
            
            String name = directories[idx];
            name.Cat("/");
            name.Cat(event->name);
            
            LOG(name);
            
            if(event->mask & IN_ISDIR) {
                if(event->mask & IN_CREATE) {
                    DirCreated(name);
                }
                else if(event->mask & IN_DELETE) {
                    DirDeleted(name);
                }
                else if(event->mask & IN_DELETE_SELF) {
                    DirDeleted(name);
                }
                else if(event->mask & IN_MOVED_FROM) {
                    DirMovedFrom(name);
                }
                else if(event->mask & IN_MOVED_TO) {
                    DirMovedTo(name);
                }
            }
            else {
                if(event->mask & IN_CREATE) {
                    FileCreated(name);
                }
                else if(event->mask & IN_DELETE) {
                    FileDeleted(name);
                }
                else if(event->mask & IN_MOVED_FROM) {
                    FileMovedFrom(name);
                }
                else if(event->mask & IN_MOVED_TO) {
                    FileMovedTo(name);
                }
            }
            
            i += EVENT_SIZE + event->len;
        }
        
        directories.Sweep();
        watches.Sweep();
    }
    
    INotify() : fd(inotify_init1(IN_NONBLOCK)) {
        if(!fd) {
            LOG("inotify failed!");
        }
        
        LOG("inotify started");
        buffer.Alloc(BUFFER_SIZE);
    }
    
    ~INotify() {
        for(int i = 0; i < watches.GetCount(); i++) {
            inotify_rm_watch(fd, watches[i]);
        }
        
        LOG("inotify closed");
        close(fd);
    }
    
    Event<String> FileCreated;
    Event<String> FileDeleted;
    Event<String> FileMovedFrom;
    Event<String> FileMovedTo;
    
    Event<String> DirCreated;
    Event<String> DirDeleted;
    Event<String> DirMovedFrom;
    Event<String> DirMovedTo;
};

void IdeBackgroundThread()
{
    StdLogSetup(LOG_COUT);
    VectorMap<String, String> file;
    Index<String> dir;
    Index<String> filei;
    
    for(FindFile ff(ConfigFile("*.var")); ff && !Thread::IsShutdownThreads(); ff.Next()) {
        VectorMap<String, String> var;
        LoadVarFile(ff.GetPath(), var);
        for(String d : Split(var.Get("UPP", ""), ';'))
            dir.FindAdd(NormalizePath(d));
        Sleep(0);
    }
    
    INotify notify;
    notify.FileCreated   = [&](String name) { LOG(Format("File Created: %s", name));   filei.Add(name);       };
    notify.FileDeleted   = [&](String name) { LOG(Format("File Deleted: %s", name));   filei.RemoveKey(name); };
    notify.FileMovedFrom = [&](String name) { LOG(Format("File MovedFrom: %s", name)); filei.RemoveKey(name); };
    notify.FileMovedTo   = [&](String name) { LOG(Format("File MovedTo: %s", name));   filei.Add(name);       };
    notify.DirCreated    = [&](String name) { LOG(Format("Dir Created: %s", name));    dir.Add(name);         notify.AddWatchRecursive(name);    };
    notify.DirDeleted    = [&](String name) { LOG(Format("Dir Deleted: %s", name));    dir.RemoveKey(name);   notify.RemoveWatch(name); };
    notify.DirMovedFrom  = [&](String name) { LOG(Format("Dir MovedFrom: %s", name));  dir.RemoveKey(name);   notify.RemoveWatch(name); };
    notify.DirMovedTo    = [&](String name) { LOG(Format("Dir MovedTo: %s", name));    dir.Add(name);         notify.AddWatchRecursive(name);    };
    
    LOG(dir);
    
    for(String d : dir) {
        GatherAllFiles(d, filei, file);
        notify.AddWatch(d);
    }
    
    for(;;) {
        notify.Run();
        Sleep(100);
    }
}

CONSOLE_APP_MAIN {
    auto configFile = ConfigFile("*.var");
    
    LOG(ConfigFile("*.var"));
    IdeBackgroundThread();
}