package fasthttp

import (
	"fmt"
	"strings"
	"sync/atomic"

	logging "git.loafle.net/commons/logging-go"
	"git.loafle.net/commons/server-go"
	"git.loafle.net/commons/server-go/web"

	"github.com/valyala/fasthttp"
)

type ServerHandler interface {
	web.ServerHandler

	OnError(serverCtx server.ServerCtx, ctx *fasthttp.RequestCtx, err *web.Error)

	RegisterServlet(path string, servlet Servlet)
	Servlet(serverCtx server.ServerCtx, ctx *fasthttp.RequestCtx) Servlet

	CheckOrigin(ctx *fasthttp.RequestCtx) bool
}

type ServerHandlers struct {
	web.ServerHandlers

	ErrorServelt Servlet `json:"-"`

	// path = context only.
	// ex) /auth => /auth, /auth/member => /auth
	servlets map[string]Servlet

	validated atomic.Value
}

func (sh *ServerHandlers) Init(serverCtx server.ServerCtx) error {
	if err := sh.ServerHandlers.Init(serverCtx); nil != err {
		return err
	}

	if nil != sh.servlets {
		for _, servlet := range sh.servlets {
			if err := servlet.Init(serverCtx); nil != err {
				return err
			}
		}
	}

	return nil
}

func (sh *ServerHandlers) OnStart(serverCtx server.ServerCtx) error {
	if err := sh.ServerHandlers.OnStart(serverCtx); nil != err {
		return err
	}

	if nil != sh.servlets {
		for _, servlet := range sh.servlets {
			if err := servlet.OnStart(serverCtx); nil != err {
				return err
			}
		}
	}

	return nil
}

func (sh *ServerHandlers) OnStop(serverCtx server.ServerCtx) {
	if nil != sh.servlets {
		for _, servlet := range sh.servlets {
			servlet.OnStop(serverCtx)
		}
	}

	sh.ServerHandlers.OnStop(serverCtx)
}

func (sh *ServerHandlers) Destroy(serverCtx server.ServerCtx) {
	if nil != sh.servlets {
		for _, servlet := range sh.servlets {
			servlet.Destroy(serverCtx)
		}
	}

	sh.ServerHandlers.Destroy(serverCtx)
}

func (sh *ServerHandlers) OnError(serverCtx server.ServerCtx, ctx *fasthttp.RequestCtx, err *web.Error) {
	if nil != sh.ErrorServelt {
		servletCtx := sh.ErrorServelt.ServletCtx(serverCtx)
		servletCtx.SetAttribute(web.ErrorKey, err)
		sh.ErrorServelt.Handle(servletCtx, ctx)
		return
	}

	ctx.Error(err.Cause.Error(), err.Code)
}

func (sh *ServerHandlers) RegisterServlet(contextPath string, servlet Servlet) {
	if nil == sh.servlets {
		sh.servlets = make(map[string]Servlet)
	}
	servlet.setContextPath(contextPath)
	sh.servlets[contextPath] = servlet
}

func (sh *ServerHandlers) Servlet(serverCtx server.ServerCtx, ctx *fasthttp.RequestCtx) Servlet {
	path := string(ctx.Path())
	contextPath, err := getContextPath(path)
	if nil != err {
		logging.Logger().Warnf("Bad Request %v", err)
		return nil
	}

	var servlet Servlet
	if servlet = sh.servlets[contextPath]; nil == servlet {
		logging.Logger().Warnf("Servlet is not exist for url[%s]", path)
		return nil
	}

	return servlet
}

func (sh *ServerHandlers) CheckOrigin(ctx *fasthttp.RequestCtx) bool {
	return true
}

func (sh *ServerHandlers) Validate() error {
	if nil != sh.validated.Load() {
		return nil
	}
	sh.validated.Store(true)

	if err := sh.ServerHandlers.Validate(); nil != err {
		return err
	}

	return nil
}

func getContextPath(path string) (string, error) {
	p := strings.TrimSpace(path)

	if !strings.HasPrefix(p, "/") {
		return "", fmt.Errorf("path[%s] must started /", path)
	}
	p = p[1:]

	if strings.HasSuffix(p, "/") {
		cpl := len(p) - 1
		p = p[:cpl]
	}

	components := strings.Split(p, "/")
	if 0 == len(components) {
		return "", fmt.Errorf("path[%s] is not invalid", path)
	}

	return fmt.Sprintf("/%s", components[0]), nil
}