package audit

import (
	"bytes"
	"io"
	"strings"

	"github.com/gin-gonic/gin"
)

type ActorResolver func(*gin.Context) (id string, name string)

func Middleware(sourceService string, resolveActor ActorResolver) gin.HandlerFunc {
	sourceService = strings.TrimSpace(sourceService)
	return func(ctx *gin.Context) {
		if ctx.Request.Method == "GET" || ctx.Request.Method == "HEAD" || ctx.Request.Method == "OPTIONS" {
			ctx.Next()
			return
		}

		var body []byte
		if ctx.Request.Body != nil {
			body, _ = io.ReadAll(ctx.Request.Body)
			ctx.Request.Body = io.NopCloser(bytes.NewBuffer(body))
		}
		ctx.Next()

		actorID, actorName := "", ""
		if resolveActor != nil {
			actorID, actorName = resolveActor(ctx)
		}
		if actorID == "" {
			actorID = firstNonEmpty(ctx.GetHeader("X-User-Id"), ctx.GetHeader("X-Actor-Id"), "unknown")
		}
		if actorName == "" {
			actorName = firstNonEmpty(ctx.GetHeader("X-User-Name"), ctx.GetHeader("X-Actor-Name"))
		}
		result := "success"
		if len(ctx.Errors) > 0 || ctx.Writer.Status() >= 400 {
			result = "failed"
		}
		_, _ = SaveRecord(Record{
			TraceID:       firstNonEmpty(ctx.GetHeader("X-Trace-Id"), ctx.GetHeader("Request-Id")),
			SourceService: sourceService,
			ActorID:       actorID,
			ActorName:     actorName,
			Action:        ctx.Request.Method + " " + ctx.FullPath(),
			ObjectType:    routeObjectType(ctx.FullPath()),
			ObjectID:      firstNonEmpty(ctx.Param("id"), ctx.Query("id"), ctx.FullPath()),
			RequestMethod: ctx.Request.Method,
			RequestPath:   ctx.FullPath(),
			ClientIP:      ctx.ClientIP(),
			AfterJSON:     string(body),
			Result:        result,
		})
	}
}

func routeObjectType(path string) string {
	path = strings.Trim(path, "/")
	if path == "" {
		return "unknown"
	}
	parts := strings.Split(path, "/")
	return parts[len(parts)-1]
}