/*
Copyright 2016 The Kubernetes Authors 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 tiller

import (
	"fmt"
	"k8s.io/helm/pkg/proto/hapi/release"
	"k8s.io/helm/pkg/proto/hapi/services"
	relutil "k8s.io/helm/pkg/releaseutil"
	"regexp"
)

// ListReleases lists the releases found by the server.
func (s *ReleaseServer) ListReleases(req *services.ListReleasesRequest, stream services.ReleaseService_ListReleasesServer) error {
	if len(req.StatusCodes) == 0 {
		req.StatusCodes = []release.Status_Code{release.Status_DEPLOYED}
	}

	//rels, err := s.env.Releases.ListDeployed()
	rels, err := s.env.Releases.ListFilterAll(func(r *release.Release) bool {
		for _, sc := range req.StatusCodes {
			if sc == r.Info.Status.Code {
				return true
			}
		}
		return false
	})
	if err != nil {
		return err
	}

	if req.Namespace != "" {
		rels, err = filterByNamespace(req.Namespace, rels)
		if err != nil {
			return err
		}
	}

	if len(req.Filter) != 0 {
		rels, err = filterReleases(req.Filter, rels)
		if err != nil {
			return err
		}
	}

	total := int64(len(rels))

	switch req.SortBy {
	case services.ListSort_NAME:
		relutil.SortByName(rels)
	case services.ListSort_LAST_RELEASED:
		relutil.SortByDate(rels)
	}

	if req.SortOrder == services.ListSort_DESC {
		ll := len(rels)
		rr := make([]*release.Release, ll)
		for i, item := range rels {
			rr[ll-i-1] = item
		}
		rels = rr
	}

	l := int64(len(rels))
	if req.Offset != "" {

		i := -1
		for ii, cur := range rels {
			if cur.Name == req.Offset {
				i = ii
			}
		}
		if i == -1 {
			return fmt.Errorf("offset %q not found", req.Offset)
		}

		if len(rels) < i {
			return fmt.Errorf("no items after %q", req.Offset)
		}

		rels = rels[i:]
		l = int64(len(rels))
	}

	if req.Limit == 0 {
		req.Limit = ListDefaultLimit
	}

	next := ""
	if l > req.Limit {
		next = rels[req.Limit].Name
		rels = rels[0:req.Limit]
		l = int64(len(rels))
	}

	res := &services.ListReleasesResponse{
		Next:     next,
		Count:    l,
		Total:    total,
		Releases: rels,
	}
	return stream.Send(res)
}

func filterByNamespace(namespace string, rels []*release.Release) ([]*release.Release, error) {
	matches := []*release.Release{}
	for _, r := range rels {
		if namespace == r.Namespace {
			matches = append(matches, r)
		}
	}
	return matches, nil
}

func filterReleases(filter string, rels []*release.Release) ([]*release.Release, error) {
	preg, err := regexp.Compile(filter)
	if err != nil {
		return rels, err
	}
	matches := []*release.Release{}
	for _, r := range rels {
		if preg.MatchString(r.Name) {
			matches = append(matches, r)
		}
	}
	return matches, nil
}