package command

import (
	"fmt"
	"net/http"
	"strings"
	"sync"
	"time"

	"github.com/hashicorp/golang-lru/v2/expirable"
	"github.com/keegancsmith/rpc"
	"gitlab.com/wpetit/goweb/logger"

	"forge.cadoles.com/arcad/edge/pkg/storage/driver"
	"forge.cadoles.com/arcad/edge/pkg/storage/driver/rpc/server"
	"github.com/go-chi/chi/v5"
	"github.com/go-chi/chi/v5/middleware"
	"github.com/pkg/errors"
	"github.com/urfave/cli/v2"

	// Register storage drivers
	_ "forge.cadoles.com/arcad/edge/pkg/storage/driver/rpc"
	_ "forge.cadoles.com/arcad/edge/pkg/storage/driver/sqlite"
)

func Run() *cli.Command {
	return &cli.Command{
		Name:  "run",
		Usage: "Run server",
		Flags: []cli.Flag{
			&cli.StringFlag{
				Name:    "address",
				Aliases: []string{"addr"},
				Value:   ":3001",
			},
			&cli.StringFlag{
				Name:    "blobstore-dsn-pattern",
				EnvVars: []string{"STORAGE_SERVER_BLOBSTORE_DSN_PATTERN"},
				Value:   fmt.Sprintf("sqlite://data/%%TENANT%%/%%APPID%%/blobstore.sqlite?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d", (60 * time.Second).Milliseconds()),
			},
			&cli.StringFlag{
				Name:    "documentstore-dsn-pattern",
				EnvVars: []string{"STORAGE_SERVER_DOCUMENTSTORE_DSN_PATTERN"},
				Value:   fmt.Sprintf("sqlite://data/%%TENANT%%/%%APPID%%/documentstore.sqlite?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d", (60 * time.Second).Milliseconds()),
			},
			&cli.DurationFlag{
				Name:    "cache-ttl",
				EnvVars: []string{"STORAGE_SERVER_CACHE_TTL"},
				Value:   time.Hour,
			},
			&cli.IntFlag{
				Name:    "cache-size",
				EnvVars: []string{"STORAGE_SERVER_CACHE_SIZE"},
				Value:   32,
			},
		},
		Action: func(ctx *cli.Context) error {
			addr := ctx.String("address")
			blobstoreDSNPattern := ctx.String("blobstore-dsn-pattern")
			documentstoreDSNPattern := ctx.String("documentstore-dsn-pattern")
			cacheSize := ctx.Int("cache-size")
			cacheTTL := ctx.Duration("cache-ttl")

			router := chi.NewRouter()

			router.Use(middleware.RealIP)
			router.Use(middleware.Logger)

			router.Handle("/blobstore", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				tenant := r.URL.Query().Get("tenant")
				if tenant == "" {
					http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)

					return
				}

				appID := r.URL.Query().Get("appId")
				if tenant == "" {
					http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)

					return
				}

				server, err := getBlobStoreStoreServer(cacheSize, cacheTTL, tenant, appID, blobstoreDSNPattern)
				if err != nil {
					logger.Error(r.Context(), "could not retrieve blob store server", logger.E(errors.WithStack(err)), logger.F("tenant", tenant))
					http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)

					return
				}

				server.ServeHTTP(w, r)
			}))

			router.Handle("/documentstore", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				tenant := r.URL.Query().Get("tenant")
				if tenant == "" {
					http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)

					return
				}

				appID := r.URL.Query().Get("appId")
				if tenant == "" {
					http.Error(w, http.StatusText(http.StatusBadRequest), http.StatusBadRequest)

					return
				}

				server, err := getDocumentStoreServer(cacheSize, cacheTTL, tenant, appID, documentstoreDSNPattern)
				if err != nil {
					logger.Error(r.Context(), "could not retrieve document store server", logger.E(errors.WithStack(err)), logger.F("tenant", tenant))
					http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)

					return
				}

				server.ServeHTTP(w, r)
			}))

			if err := http.ListenAndServe(addr, router); err != nil {
				return errors.WithStack(err)
			}

			return nil
		},
	}
}

var (
	documentStoreCache     *expirable.LRU[string, *rpc.Server]
	initDocumentStoreCache sync.Once
)

func getDocumentStoreServer(cacheSize int, cacheTTL time.Duration, tenant, appID, dsnPattern string) (*rpc.Server, error) {
	initDocumentStoreCache.Do(func() {
		documentStoreCache = expirable.NewLRU[string, *rpc.Server](cacheSize, nil, cacheTTL)
	})

	key := fmt.Sprintf("%s:%s", tenant, appID)

	documentStoreServer, _ := documentStoreCache.Get(key)
	if documentStoreServer != nil {
		return documentStoreServer, nil
	}

	dsn := strings.ReplaceAll(dsnPattern, "%TENANT%", tenant)
	dsn = strings.ReplaceAll(dsn, "%APPID%", appID)

	documentStore, err := driver.NewDocumentStore(dsn)
	if err != nil {
		return nil, errors.WithStack(err)
	}

	documentStoreServer = server.NewDocumentStoreServer(documentStore)

	documentStoreCache.Add(key, documentStoreServer)

	return documentStoreServer, nil
}

var (
	blobStoreCache     *expirable.LRU[string, *rpc.Server]
	initBlobStoreCache sync.Once
)

func getBlobStoreStoreServer(cacheSize int, cacheTTL time.Duration, tenant, appID, dsnPattern string) (*rpc.Server, error) {
	initBlobStoreCache.Do(func() {
		blobStoreCache = expirable.NewLRU[string, *rpc.Server](cacheSize, nil, cacheTTL)
	})

	key := fmt.Sprintf("%s:%s", tenant, appID)

	blobStoreServer, _ := blobStoreCache.Get(key)
	if blobStoreServer != nil {
		return blobStoreServer, nil
	}

	dsn := strings.ReplaceAll(dsnPattern, "%TENANT%", tenant)
	dsn = strings.ReplaceAll(dsn, "%APPID%", appID)

	blobStore, err := driver.NewBlobStore(dsn)
	if err != nil {
		return nil, errors.WithStack(err)
	}

	blobStoreServer = server.NewBlobStoreServer(blobStore)

	blobStoreCache.Add(key, blobStoreServer)

	return blobStoreServer, nil
}