// Copyright 2016 Circonus, Inc. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Metric Cluster API support - Fetch, Create, Update, Delete, and Search
// See: https://login.circonus.com/resources/api/calls/metric_cluster

package api

import (
	"encoding/json"
	"fmt"
	"net/url"
	"regexp"

	"github.com/circonus-labs/circonus-gometrics/api/config"
)

// MetricQuery object
type MetricQuery struct {
	Query string `json:"query"`
	Type  string `json:"type"`
}

// MetricCluster defines a metric cluster. See https://login.circonus.com/resources/api/calls/metric_cluster for more information.
type MetricCluster struct {
	CID                 string              `json:"_cid,omitempty"`                   // string
	Description         string              `json:"description"`                      // string
	MatchingMetrics     []string            `json:"_matching_metrics,omitempty"`      // [] len >= 1 (result info only, if query has extras - cannot be set)
	MatchingUUIDMetrics map[string][]string `json:"_matching_uuid_metrics,omitempty"` // [] len >= 1 (result info only, if query has extras - cannot be set)
	Name                string              `json:"name"`                             // string
	Queries             []MetricQuery       `json:"queries"`                          // [] len >= 1
	Tags                []string            `json:"tags"`                             // [] len >= 0
}

// NewMetricCluster returns a new MetricCluster (with defaults, if applicable)
func NewMetricCluster() *MetricCluster {
	return &MetricCluster{}
}

// FetchMetricCluster retrieves metric cluster with passed cid.
func (a *API) FetchMetricCluster(cid CIDType, extras string) (*MetricCluster, error) {
	if cid == nil || *cid == "" {
		return nil, fmt.Errorf("Invalid metric cluster CID [none]")
	}

	clusterCID := string(*cid)

	matched, err := regexp.MatchString(config.MetricClusterCIDRegex, clusterCID)
	if err != nil {
		return nil, err
	}
	if !matched {
		return nil, fmt.Errorf("Invalid metric cluster CID [%s]", clusterCID)
	}

	reqURL := url.URL{
		Path: clusterCID,
	}

	extra := ""
	switch extras {
	case "metrics":
		extra = "_matching_metrics"
	case "uuids":
		extra = "_matching_uuid_metrics"
	}

	if extra != "" {
		q := url.Values{}
		q.Set("extra", extra)
		reqURL.RawQuery = q.Encode()
	}

	result, err := a.Get(reqURL.String())
	if err != nil {
		return nil, err
	}

	if a.Debug {
		a.Log.Printf("[DEBUG] fetch metric cluster, received JSON: %s", string(result))
	}

	cluster := &MetricCluster{}
	if err := json.Unmarshal(result, cluster); err != nil {
		return nil, err
	}

	return cluster, nil
}

// FetchMetricClusters retrieves all metric clusters available to API Token.
func (a *API) FetchMetricClusters(extras string) (*[]MetricCluster, error) {
	reqURL := url.URL{
		Path: config.MetricClusterPrefix,
	}

	extra := ""
	switch extras {
	case "metrics":
		extra = "_matching_metrics"
	case "uuids":
		extra = "_matching_uuid_metrics"
	}

	if extra != "" {
		q := url.Values{}
		q.Set("extra", extra)
		reqURL.RawQuery = q.Encode()
	}

	result, err := a.Get(reqURL.String())
	if err != nil {
		return nil, err
	}

	var clusters []MetricCluster
	if err := json.Unmarshal(result, &clusters); err != nil {
		return nil, err
	}

	return &clusters, nil
}

// UpdateMetricCluster updates passed metric cluster.
func (a *API) UpdateMetricCluster(cfg *MetricCluster) (*MetricCluster, error) {
	if cfg == nil {
		return nil, fmt.Errorf("Invalid metric cluster config [nil]")
	}

	clusterCID := string(cfg.CID)

	matched, err := regexp.MatchString(config.MetricClusterCIDRegex, clusterCID)
	if err != nil {
		return nil, err
	}
	if !matched {
		return nil, fmt.Errorf("Invalid metric cluster CID [%s]", clusterCID)
	}

	jsonCfg, err := json.Marshal(cfg)
	if err != nil {
		return nil, err
	}

	if a.Debug {
		a.Log.Printf("[DEBUG] update metric cluster, sending JSON: %s", string(jsonCfg))
	}

	result, err := a.Put(clusterCID, jsonCfg)
	if err != nil {
		return nil, err
	}

	cluster := &MetricCluster{}
	if err := json.Unmarshal(result, cluster); err != nil {
		return nil, err
	}

	return cluster, nil
}

// CreateMetricCluster creates a new metric cluster.
func (a *API) CreateMetricCluster(cfg *MetricCluster) (*MetricCluster, error) {
	if cfg == nil {
		return nil, fmt.Errorf("Invalid metric cluster config [nil]")
	}

	jsonCfg, err := json.Marshal(cfg)
	if err != nil {
		return nil, err
	}

	if a.Debug {
		a.Log.Printf("[DEBUG] create metric cluster, sending JSON: %s", string(jsonCfg))
	}

	result, err := a.Post(config.MetricClusterPrefix, jsonCfg)
	if err != nil {
		return nil, err
	}

	cluster := &MetricCluster{}
	if err := json.Unmarshal(result, cluster); err != nil {
		return nil, err
	}

	return cluster, nil
}

// DeleteMetricCluster deletes passed metric cluster.
func (a *API) DeleteMetricCluster(cfg *MetricCluster) (bool, error) {
	if cfg == nil {
		return false, fmt.Errorf("Invalid metric cluster config [nil]")
	}
	return a.DeleteMetricClusterByCID(CIDType(&cfg.CID))
}

// DeleteMetricClusterByCID deletes metric cluster with passed cid.
func (a *API) DeleteMetricClusterByCID(cid CIDType) (bool, error) {
	if cid == nil || *cid == "" {
		return false, fmt.Errorf("Invalid metric cluster CID [none]")
	}

	clusterCID := string(*cid)

	matched, err := regexp.MatchString(config.MetricClusterCIDRegex, clusterCID)
	if err != nil {
		return false, err
	}
	if !matched {
		return false, fmt.Errorf("Invalid metric cluster CID [%s]", clusterCID)
	}

	_, err = a.Delete(clusterCID)
	if err != nil {
		return false, err
	}

	return true, nil
}

// SearchMetricClusters returns metric clusters matching the specified
// search query and/or filter. If nil is passed for both parameters
// all metric clusters will be returned.
func (a *API) SearchMetricClusters(searchCriteria *SearchQueryType, filterCriteria *SearchFilterType) (*[]MetricCluster, error) {
	q := url.Values{}

	if searchCriteria != nil && *searchCriteria != "" {
		q.Set("search", string(*searchCriteria))
	}

	if filterCriteria != nil && len(*filterCriteria) > 0 {
		for filter, criteria := range *filterCriteria {
			for _, val := range criteria {
				q.Add(filter, val)
			}
		}
	}

	if q.Encode() == "" {
		return a.FetchMetricClusters("")
	}

	reqURL := url.URL{
		Path:     config.MetricClusterPrefix,
		RawQuery: q.Encode(),
	}

	result, err := a.Get(reqURL.String())
	if err != nil {
		return nil, fmt.Errorf("[ERROR] API call error %+v", err)
	}

	var clusters []MetricCluster
	if err := json.Unmarshal(result, &clusters); err != nil {
		return nil, err
	}

	return &clusters, nil
}