package logic

import (
	scn "blackforestbytes.com/simplecloudnotifier"
	"blackforestbytes.com/simplecloudnotifier/api/apierr"
	"blackforestbytes.com/simplecloudnotifier/api/ginresp"
	"blackforestbytes.com/simplecloudnotifier/models"
	"context"
	"errors"
	"fmt"
	"github.com/gin-gonic/gin"
	"github.com/glebarez/go-sqlite"
	"github.com/rs/zerolog/log"
	"gogs.mikescher.com/BlackForestBytes/goext/dataext"
	"gogs.mikescher.com/BlackForestBytes/goext/exerr"
	"gogs.mikescher.com/BlackForestBytes/goext/ginext"
	"gogs.mikescher.com/BlackForestBytes/goext/langext"
	"math/rand"
	"runtime/debug"
	"time"
)

type RequestOptions struct {
	IgnoreWrongContentType bool
}

func (app *Application) DoRequest(gectx *ginext.AppContext, g *gin.Context, lockmode models.TransactionLockMode, fn func(ctx *AppContext, finishSuccess func(r ginext.HTTPResponse) ginext.HTTPResponse) ginext.HTTPResponse) ginext.HTTPResponse {

	maxRetry := scn.Conf.RequestMaxRetry
	retrySleep := scn.Conf.RequestRetrySleep

	reqctx := g.Request.Context()

	t0 := time.Now()

	for ctr := 1; ; ctr++ {

		ictx, cancel := context.WithTimeout(gectx, app.Config.RequestTimeout)

		actx := CreateAppContext(app, g, ictx, cancel)

		wrap, stackTrace, panicObj := callPanicSafe(func(ctx *AppContext, finishSuccess func(r ginext.HTTPResponse) ginext.HTTPResponse) ginext.HTTPResponse {

			dl, ok := ctx.Deadline()
			if !ok {
				dl = time.Now().Add(time.Second * 5)
			}

			if lockmode == models.TLockRead {

				islock := app.MainDatabaseLock.RTryLockWithTimeout(dl.Sub(time.Now()))
				if !islock {
					return ginresp.APIError(g, 500, apierr.INTERNAL_EXCEPTION, "Failed to lock {MainDatabaseLock} [ro]", nil)
				}
				defer app.MainDatabaseLock.RUnlock()

			} else if lockmode == models.TLockReadWrite {

				islock := app.MainDatabaseLock.TryLockWithTimeout(dl.Sub(time.Now()))
				if !islock {
					return ginresp.APIError(g, 500, apierr.INTERNAL_EXCEPTION, "Failed to lock {MainDatabaseLock} [rw]", nil)
				}
				defer app.MainDatabaseLock.Unlock()

			}

			authheader := g.GetHeader("Authorization")

			perm, err := app.getPermissions(actx, authheader)
			if err != nil {
				cancel()
				return ginresp.APIError(g, 400, apierr.PERM_QUERY_FAIL, "Failed to determine permissions", err)
			}

			actx.permissions = perm
			g.Set("perm", perm)

			return fn(actx, finishSuccess)

		}, actx, actx._FinishSuccess)
		if panicObj != nil {
			log.Error().Interface("panicObj", panicObj).Msg("Panic occured (in gin handler)")
			log.Error().Msg(stackTrace)
			wrap = ginresp.APIError(g, 500, apierr.PANIC, "A panic occured in the HTTP handler", errors.New(fmt.Sprintf("%+v\n\n@:\n%s", panicObj, stackTrace)))
		}

		if g.Writer.Written() {
			if scn.Conf.ReqLogEnabled {
				app.InsertRequestLog(createRequestLog(g, t0, ctr, nil, langext.Ptr("Writing in WrapperFunc is not supported")))
			}
			panic("Writing in WrapperFunc is not supported")
		}

		if ctr < maxRetry && isSqlite3Busy(wrap) {
			log.Warn().Int("counter", ctr).Str("url", g.Request.URL.String()).Msg("Retry request (ErrBusy)")

			err := resetBody(g)
			if err != nil {
				panic(err)
			}

			time.Sleep(time.Duration(int64(float64(retrySleep) * (0.5 + rand.Float64()))))
			continue
		}

		if reqctx.Err() == nil {
			if scn.Conf.ReqLogEnabled {
				app.InsertRequestLog(createRequestLog(g, t0, ctr, wrap, nil))
			}

			if scw, ok := wrap.(ginext.InspectableHTTPResponse); ok {

				statuscode := scw.Statuscode()
				if statuscode/100 != 2 {
					log.Warn().Str("url", g.Request.Method+"::"+g.Request.URL.String()).Msg(fmt.Sprintf("Request failed with statuscode %d", statuscode))
				}
			} else {
				log.Warn().Str("url", g.Request.Method+"::"+g.Request.URL.String()).Msg(fmt.Sprintf("Request failed with statuscode [unknown]"))
			}
		}

		return wrap
	}

}

func callPanicSafe(fn func(ctx *AppContext, finishSuccess func(r ginext.HTTPResponse) ginext.HTTPResponse) ginext.HTTPResponse, actx *AppContext, fnFin func(r ginext.HTTPResponse) ginext.HTTPResponse) (res ginext.HTTPResponse, stackTrace string, panicObj any) {
	defer func() {
		if rec := recover(); rec != nil {
			res = nil
			stackTrace = string(debug.Stack())
			panicObj = rec
		}
	}()

	res = fn(actx, fnFin)
	return res, "", nil
}

func createRequestLog(g *gin.Context, t0 time.Time, ctr int, resp ginext.HTTPResponse, panicstr *string) models.RequestLog {

	t1 := time.Now()

	ua := g.Request.UserAgent()
	auth := g.Request.Header.Get("Authorization")
	ct := g.Request.Header.Get("Content-Type")

	var reqbody []byte = nil
	if g.Request.Body != nil {
		brcbody, err := g.Request.Body.(dataext.BufferedReadCloser).BufferedAll()
		if err == nil {
			reqbody = brcbody
		}
	}
	var strreqbody *string = nil
	if len(reqbody) < scn.Conf.ReqLogMaxBodySize {
		strreqbody = langext.Ptr(string(reqbody))
	}

	var respbody *string = nil

	var strrespbody *string = nil
	if resp != nil {
		if resp2, ok := resp.(ginext.InspectableHTTPResponse); ok {
			respbody = resp2.BodyString(g)
			if respbody != nil && len(*respbody) < scn.Conf.ReqLogMaxBodySize {
				strrespbody = respbody
			}
		}
	}

	permObj, hasPerm := g.Get("perm")

	hasTok := false
	if hasPerm {
		hasTok = permObj.(models.PermissionSet).Token != nil
	}

	var statuscode *int64 = nil
	if resp != nil {
		if resp2, ok := resp.(ginext.InspectableHTTPResponse); ok {
			statuscode = langext.Ptr(int64(resp2.Statuscode()))
		}
	}

	var contentType = ""
	if resp != nil {
		if resp2, ok := resp.(ginext.InspectableHTTPResponse); ok {
			contentType = resp2.ContentType()
		}
	}

	return models.RequestLog{
		Method:              g.Request.Method,
		URI:                 g.Request.URL.String(),
		UserAgent:           langext.Conditional(ua == "", nil, &ua),
		Authentication:      langext.Conditional(auth == "", nil, &auth),
		RequestBody:         strreqbody,
		RequestBodySize:     int64(len(reqbody)),
		RequestContentType:  ct,
		RemoteIP:            g.RemoteIP(),
		KeyID:               langext.ConditionalFn10(hasTok, func() *models.KeyTokenID { return langext.Ptr(permObj.(models.PermissionSet).Token.KeyTokenID) }, nil),
		UserID:              langext.ConditionalFn10(hasTok, func() *models.UserID { return langext.Ptr(permObj.(models.PermissionSet).Token.OwnerUserID) }, nil),
		Permissions:         langext.ConditionalFn10(hasTok, func() *string { return langext.Ptr(permObj.(models.PermissionSet).Token.Permissions.String()) }, nil),
		ResponseStatuscode:  statuscode,
		ResponseBodySize:    langext.ConditionalFn10(strrespbody != nil, func() *int64 { return langext.Ptr(int64(len(*respbody))) }, nil),
		ResponseBody:        strrespbody,
		ResponseContentType: contentType,
		RetryCount:          int64(ctr),
		Panicked:            panicstr != nil,
		PanicStr:            panicstr,
		ProcessingTime:      models.SCNDuration(t1.Sub(t0)),
		TimestampStart:      models.NewSCNTime(t0),
		TimestampFinish:     models.NewSCNTime(t1),
	}
}

func resetBody(g *gin.Context) error {
	if g.Request.Body == nil {
		return nil
	}

	err := g.Request.Body.(dataext.BufferedReadCloser).Reset()
	if err != nil {
		return err
	}

	return nil
}

func isSqlite3Busy(r ginext.HTTPResponse) bool {
	if errwrap, ok := r.(interface{ Unwrap() error }); ok && errwrap != nil {
		orig := exerr.OriginalError(errwrap.Unwrap())

		var sqliteErr *sqlite.Error
		if errors.As(orig, &sqliteErr) {
			if sqliteErr.Code() == 5 { // [5] == SQLITE_BUSY
				return true
			}
			if sqliteErr.Code() == 517 { // [517] == SQLITE_BUSY_SNAPSHOT
				return true
			}
			if sqliteErr.Code() == 261 { // [261] == SQLITE_BUSY_RECOVERY
				return true
			}
			if sqliteErr.Code() == 773 { // [773] == SQLITE_BUSY_TIMEOUT
				return true
			}
		}
	}
	return false
}

func BuildGinRequestError(g *gin.Context, fieldtype string, err error) ginext.HTTPResponse {
	switch fieldtype {
	case "URI":
		return ginresp.APIError(g, 400, apierr.BINDFAIL_URI_PARAM, "Failed to read uri", err)
	case "QUERY":
		return ginresp.APIError(g, 400, apierr.BINDFAIL_QUERY_PARAM, "Failed to read query", err)
	case "JSON":
		return ginresp.APIError(g, 400, apierr.BINDFAIL_BODY_PARAM, "Failed to read JSON body", err)
	case "BODY":
		return ginresp.APIError(g, 400, apierr.BINDFAIL_BODY_PARAM, "Failed to read query", err)
	case "FORM":
		return ginresp.APIError(g, 400, apierr.BINDFAIL_BODY_PARAM, "Failed to read multipart-form / urlencoded-form", err)
	case "HEADER":
		return ginresp.APIError(g, 400, apierr.BINDFAIL_HEADER_PARAM, "Failed to read header", err)
	case "INIT":
		return ginresp.APIError(g, 400, apierr.INTERNAL_EXCEPTION, "Failed to init context", err)
	default:
		return ginresp.APIError(g, 400, apierr.INTERNAL_EXCEPTION, "Failed to init", err)
	}
}