/*
   Copyright (c) 2016 VMware, Inc. All Rights Reserved.
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package api

import (
	"fmt"
	"net"
	"net/http"
	"net/url"
	"strconv"

	"github.com/vmware/harbor/dao"
	"github.com/vmware/harbor/models"
	"github.com/vmware/harbor/utils"
	"github.com/vmware/harbor/utils/log"
	registry_util "github.com/vmware/harbor/utils/registry"
	"github.com/vmware/harbor/utils/registry/auth"
	registry_error "github.com/vmware/harbor/utils/registry/error"
)

// TargetAPI handles request to /api/targets/ping /api/targets/{}
type TargetAPI struct {
	BaseAPI
}

// Prepare validates the user
func (t *TargetAPI) Prepare() {
	userID := t.ValidateUser()
	isSysAdmin, err := dao.IsAdminRole(userID)
	if err != nil {
		log.Errorf("error occurred in IsAdminRole: %v", err)
		t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
	}

	if !isSysAdmin {
		t.CustomAbort(http.StatusForbidden, http.StatusText(http.StatusForbidden))
	}
}

// Ping validates whether the target is reachable and whether the credential is valid
func (t *TargetAPI) Ping() {
	var endpoint, username, password string

	idStr := t.GetString("id")
	if len(idStr) != 0 {
		id, err := strconv.ParseInt(idStr, 10, 64)
		if err != nil {
			t.CustomAbort(http.StatusBadRequest, fmt.Sprintf("id %s is invalid", idStr))
		}

		target, err := dao.GetRepTarget(id)
		if err != nil {
			log.Errorf("failed to get target %d: %v", id, err)
			t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
		}

		if target == nil {
			t.CustomAbort(http.StatusNotFound, http.StatusText(http.StatusNotFound))
		}

		endpoint = target.URL
		username = target.Username
		password = target.Password

		if len(password) != 0 {
			password, err = utils.ReversibleDecrypt(password)
			if err != nil {
				log.Errorf("failed to decrypt password: %v", err)
				t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
			}
		}
	} else {
		endpoint = t.GetString("endpoint")
		if len(endpoint) == 0 {
			t.CustomAbort(http.StatusBadRequest, "id or endpoint is needed")
		}

		username = t.GetString("username")
		password = t.GetString("password")
	}

	credential := auth.NewBasicAuthCredential(username, password)
	registry, err := registry_util.NewRegistryWithCredential(endpoint, credential)
	if err != nil {
		// timeout, dns resolve error, connection refused, etc.
		if urlErr, ok := err.(*url.Error); ok {
			if netErr, ok := urlErr.Err.(net.Error); ok {
				t.CustomAbort(http.StatusBadRequest, netErr.Error())
			} else {
				t.CustomAbort(http.StatusBadRequest, urlErr.Error())
			}
		}

		log.Errorf("failed to create registry client: %#v", err)
		t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
	}

	if err = registry.Ping(); err != nil {
		// timeout, dns resolve error, connection refused, etc.
		if urlErr, ok := err.(*url.Error); ok {
			if netErr, ok := urlErr.Err.(net.Error); ok {
				t.CustomAbort(http.StatusBadRequest, netErr.Error())
			} else {
				t.CustomAbort(http.StatusBadRequest, urlErr.Error())
			}
		}

		if regErr, ok := err.(*registry_error.Error); ok {
			t.CustomAbort(regErr.StatusCode, regErr.Detail)
		}

		log.Errorf("failed to ping registry %s: %v", registry.Endpoint.String(), err)
		t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
	}
}

// Get ...
func (t *TargetAPI) Get() {
	id := t.getIDFromURL()
	// list targets
	if id == 0 {
		targets, err := dao.GetAllRepTargets()
		if err != nil {
			log.Errorf("failed to get all targets: %v", err)
			t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
		}

		for _, target := range targets {
			target.Password = ""
		}

		t.Data["json"] = targets
		t.ServeJSON()
		return
	}

	target, err := dao.GetRepTarget(id)
	if err != nil {
		log.Errorf("failed to get target %d: %v", id, err)
		t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
	}

	if target == nil {
		t.CustomAbort(http.StatusNotFound, http.StatusText(http.StatusNotFound))
	}

	if len(target.Password) != 0 {
		pwd, err := utils.ReversibleDecrypt(target.Password)
		if err != nil {
			log.Errorf("failed to decrypt password: %v", err)
			t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
		}
		target.Password = pwd
	}

	t.Data["json"] = target
	t.ServeJSON()
}

// Post ...
func (t *TargetAPI) Post() {
	target := &models.RepTarget{}
	t.DecodeJSONReq(target)

	if len(target.Name) == 0 || len(target.URL) == 0 {
		t.CustomAbort(http.StatusBadRequest, "name or URL is nil")
	}

	if len(target.Password) != 0 {
		target.Password = utils.ReversibleEncrypt(target.Password)
	}

	id, err := dao.AddRepTarget(*target)
	if err != nil {
		log.Errorf("failed to add target: %v", err)
		t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
	}

	t.Redirect(http.StatusCreated, strconv.FormatInt(id, 10))
}

// Put ...
func (t *TargetAPI) Put() {
	id := t.getIDFromURL()
	if id == 0 {
		t.CustomAbort(http.StatusBadRequest, http.StatusText(http.StatusBadRequest))
	}

	target := &models.RepTarget{}
	t.DecodeJSONReq(target)

	if target.ID == 0 {
		target.ID = id
	}

	if len(target.Password) != 0 {
		target.Password = utils.ReversibleEncrypt(target.Password)
	}

	if err := dao.UpdateRepTarget(*target); err != nil {
		log.Errorf("failed to update target %d: %v", id, err)
		t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
	}
}

// Delete ...
func (t *TargetAPI) Delete() {
	id := t.getIDFromURL()
	if id == 0 {
		t.CustomAbort(http.StatusBadRequest, http.StatusText(http.StatusBadRequest))
	}

	target, err := dao.GetRepTarget(id)
	if err != nil {
		log.Errorf("failed to get target %d: %v", id, err)
		t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
	}

	if target == nil {
		t.CustomAbort(http.StatusNotFound, http.StatusText(http.StatusNotFound))
	}

	if err = dao.DeleteRepTarget(id); err != nil {
		log.Errorf("failed to delete target %d: %v", id, err)
		t.CustomAbort(http.StatusInternalServerError, http.StatusText(http.StatusInternalServerError))
	}
}

func (t *TargetAPI) getIDFromURL() int64 {
	idStr := t.Ctx.Input.Param(":id")
	if len(idStr) == 0 {
		return 0
	}

	id, err := strconv.ParseInt(idStr, 10, 64)
	if err != nil {
		t.CustomAbort(http.StatusBadRequest, "invalid ID in request URL")
	}

	return id
}