package handler

import (
	"context"
	"encoding/json"
	"io"
	"net/http"
	"net/url"

	cmsstorage "go.unistack.org/cms-service/storage"
	"go.unistack.org/micro/v4"
	"go.unistack.org/micro/v4/errors"
	"go.unistack.org/unistack-org/pkgdash/config"
	pb "go.unistack.org/unistack-org/pkgdash/proto"
	cligit "go.unistack.org/unistack-org/pkgdash/service/client_git"
	"go.unistack.org/unistack-org/pkgdash/storage"
	"google.golang.org/protobuf/encoding/protojson"
	"google.golang.org/protobuf/proto"
)

type Handler struct {
	svc   micro.Service
	store storage.Storage

	writer writer
	protojson.MarshalOptions
	protojson.UnmarshalOptions

	git     cligit.Client
	chanUrl chan *pb.AddPackageReq
}

func (h *Handler) ListPackage(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	logger := h.svc.Logger()
	logger.Debug(ctx, "Start getListPackage")

	dbRsp, err := h.store.ListPackage(ctx)
	if err != nil {
		logger.Errorf(ctx, "error db response: %v", err)
		h.writer.Response(ctx, w, err)
		return
	}

	rsp := new(pb.ListPackageRsp)
	rsp.Packages = dbRsp.Decode()

	logger.Debug(ctx, "Success finish getListPackage")
	h.writer.Response(ctx, w, rsp)
}

func (h *Handler) UpdatePackage(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	logger := h.svc.Logger()
	logger.Debug(ctx, "Start UpdatePackage")

	defer r.Body.Close()
	all, err := io.ReadAll(r.Body)
	if err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewInternalError(err))
		return
	}

	req := new(pb.UpdatePackageReq)
	if err = h.Unmarshal(all, req); err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewUnmarshalError(err))
		return
	}

	if err = req.Validate(); err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewValidationError(err))
		return
	}

	if err = h.store.UpdatePackage(ctx, req); err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewInternalError(err))
		return
	}

	logger.Debug(ctx, "Success finish UpdatePackage")
}

func (h *Handler) AddComment(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	logger := h.svc.Logger()
	logger.Debug(ctx, "Start AddComment")

	defer r.Body.Close()
	all, err := io.ReadAll(r.Body)
	if err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewInternalError(err))
		return
	}

	req := new(pb.AddCommentReq)
	if err = h.Unmarshal(all, req); err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewUnmarshalError(err))
		return
	}

	if err = req.Validate(); err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewValidationError(err))
		return
	}

	if err = h.store.AddComment(ctx, req); err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewInternalError(err))
		return
	}

	logger.Debug(ctx, "Success finish addComment")
}

func (h *Handler) AddPackage(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	logger := h.svc.Logger()
	logger.Debug(ctx, "Start AddPackage")

	defer r.Body.Close()
	all, err := io.ReadAll(r.Body)
	if err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewInternalError(err))
		return
	}

	req := new(pb.AddPackageReq)
	if err = h.Unmarshal(all, req); err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewUnmarshalError(err))
		return
	}

	if err = req.Validate(); err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewValidationError(err))
		return
	}

	if h.git.IsClose() {
		logger.Error(ctx, "chan is closed")
	} else {
		h.chanUrl <- req
	}

	logger.Debug(ctx, "Success finish addPackage")
}

func (h *Handler) GetModule(w http.ResponseWriter, r *http.Request) {
	ctx := r.Context()
	logger := h.svc.Logger()
	logger.Debug(ctx, "Start GetModule")

	req := new(pb.GetModuleReq)
	if err := URLValuesToProto(r.URL.Query(), req); err != nil {
		logger.Errorf(ctx, "Required parameter missing: %v", err)
		h.writer.Response(ctx, w, err)
		return
	}

	modules, err := h.store.GetModule(ctx, req)
	if err != nil {
		logger.Error(ctx, err)
		h.writer.Response(ctx, w, NewInternalError(err))
		return
	}

	rsp := &pb.GetModuleRsp{Modules: modules.Decode()}
	h.writer.Response(ctx, w, rsp)

	logger.Debug(ctx, "Success finish getModule")
}

func URLValuesToProto(vals url.Values, msg proto.Message) error {
	params := make(map[string]interface{})
	var err error
	for k, v := range vals {
		if len(v) == 0 {
			continue
		}
		switch k {
		case "id[]":
			params[k] = v
		default:
			params[k] = v[0]
		}
	}
	b, err := json.Marshal(params)
	if err != nil {
		return NewUnmarshalError(err)
	}
	if err = protojson.Unmarshal(b, msg); err != nil {
		return NewUnmarshalError(err)
	}
	return nil
}

func NewHandler(svc micro.Service, w writer, client cligit.Client) *Handler {
	h := &Handler{
		svc:    svc,
		writer: w,
		git:    client,
	}
	h.EmitUnpopulated = true
	h.UseProtoNames = false
	return h
}

func (h *Handler) Init(ctx context.Context) error {
	store := cmsstorage.InterfaceFromContext(h.svc.Options().Context)
	if store == nil {
		return cmsstorage.ErrMissingStorage
	}
	st, ok := store.(storage.Storage)
	if !ok {
		return errors.New(config.ServiceName, "error init storage", 1)
	}

	h.chanUrl = h.git.Run(ctx, st)

	h.store = st

	return nil
}