package main

import (
	"context"
	"fmt"
	zordTree "g.arns.lt/zordsdavini/zord-tree"
	"google.golang.org/grpc"
	"io"
	"log"
	"net"
	"os"
	"path"
)

type server struct {
	UnimplementedTreeManagerServer
}

func (TreeManagerServer *server) GetSummery(_ context.Context, in *TreeRequest) (*Tree, error) {
	log.Println(in)
	tree, err := zordTree.BuildTree(source, meta)
	if err != nil {
		log.Fatal(err)
		return nil, err
	}

	if *in.Path != "" {
		ntree, err := tree.Slice(source + *in.Path)
		if err != nil {
			log.Fatal(err)
			return &Tree{}, err
		}

		tree = ntree
	}

	if len(in.Filter) != 0 {
		ntree, found := tree.Filter(simplifyFilter(in.Filter))
		if !found {
			return &Tree{}, err
		}

		tree = ntree
	}

	formattedTree := FormatTreeSummery(tree)

	return &formattedTree, nil
}

func (TreeManagerServer *server) GetFile(_ context.Context, in *FileRequest) (*FileContent, error) {
	log.Println(in)
	tree, err := zordTree.BuildTree(source, meta)
	if err != nil {
		log.Fatal(err)
		return nil, err
	}

	file, err := tree.FileById(in.Id)
	if err != nil {
		return nil, err
	}

	fileContent := GetContent(file)

	return &fileContent, nil
}

func (TreeManagerServer *server) RebuildTree(ctx context.Context, in *TreeSecret) (*RebuildResponse, error) {
	log.Println(in, key)
	success := false
	if in.Key == key {
		Collect()
		success = true
	}

	response := RebuildResponse{Success: success}
	return &response, nil
}

func (TreeManagerServer *server) DownloadAttachment(in *AttachmentRequest, responseStream TreeManager_DownloadAttachmentServer) error {
	file, err := os.Open(path.Clean(fmt.Sprintf("%s/%s/%s", source, zordTree.AttachmentDirName, in.Path)))
	if err != nil {
		return err
	}
	defer file.Close()

	bufferSize := 64 * 1024
	buff := make([]byte, bufferSize)
	for {
		bytesRead, err := file.Read(buff)
		if err != nil {
			if err != io.EOF {
				log.Println("Error during downloadingAttachment: ", err)
			}
			break
		}
		resp := &AttachmentResponse{Chunk: buff[:bytesRead]}

		err = responseStream.Send(resp)
		if err != nil {
			return err
		}
	}
	return nil
}

func simplifyFilter(filter []*TreeRequest_Filter) map[string][]string {
	simpleFilter := make(map[string][]string)
	for _, f := range filter {
		simpleFilter[f.Key] = append(simpleFilter[f.Key], f.Value)
	}

	return simpleFilter
}

func Run() {
	if _, err := os.Stat(source); os.IsNotExist(err) {
		log.Fatalf("Source directory does not exist.")
	}

	ln, err := net.Listen("tcp", ":8301")
	if err != nil {
		log.Fatalf("Failed to listen: " + err.Error())
	}

	var opts []grpc.ServerOption
	grpcServer := grpc.NewServer(opts...)
	RegisterTreeManagerServer(grpcServer, &server{})
	err = grpcServer.Serve(ln)
	if err != nil {
		log.Fatalf("failed to serve: %v", err)
	}
}