package balboa

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"time"

	"gitlab.dcso.lolcat/go/golistic/xapi"
	"gitlab.dcso.lolcat/go/golistic/xhttp"
)

const (
	headerFieldContentType = "Content-type"
	mimeTypeJSON           = "application/json"
	graphqlPath            = "/query"
)

// post GraphQL query
func (c *Client) post(ctx context.Context, query *xapi.GraphQLQuery, dest *xapi.GraphQLPayload) error {
	gqlClient := xapi.NewGraphQLClient(c.addr+graphqlPath, xhttp.OptionTimeout(2*time.Minute))
	err := gqlClient.AddMiddleware(func(ctx context.Context, r *http.Request) error {
		r.Header.Add(headerFieldContentType, mimeTypeJSON)
		return nil
	})
	if err != nil {
		return err
	}

	if err = gqlClient.Exec(ctx, query, dest); err != nil {
		return err
	}

	return nil
}

// Ping Balboa to see whether it is both available and that we can connect
// and query it.
func (c *Client) Ping(ctx context.Context) (err error) {
	resp := xapi.GraphQLPayload{}
	query := &xapi.GraphQLQuery{
		Query: queryTest,
	}

	if err = c.post(ctx, query, &resp); err != nil {
		return err
	}

	return
}

// GetAllEntries retrieves all entries for a Balboa query
func (c *Client) GetAllEntries(ctx context.Context, rrname string, rrtype string, rdata string, limit int32) ([]Entries, error) {
	resp := xapi.GraphQLPayload{}
	query := &xapi.GraphQLQuery{
		Query: queryAllEntries,
		Variables: map[string]interface{}{
			"rrname": rrname,
			"rrtype": rrtype,
			"rdata":  rdata,
			"limit":  100,
		},
	}

	if err := c.post(ctx, query, &resp); err != nil {
		return nil, err
	}

	l := EntriesList{}
	if err := json.Unmarshal(resp.Data, &l); err != nil {
		return nil, fmt.Errorf("json decode: %v", err)
	}
	return l.EntriesListItem, nil
}

// GetEntriesBySensor returns Balboa entries by sensorID
func (c *Client) GetEntriesBySensor(ctx context.Context, rrname string, rrtype string, rdata string, limit int32, sensorID string) ([]Entries, error) {
	if limit == 0 {
		limit = 100
	}
	resp := xapi.GraphQLPayload{}
	query := &xapi.GraphQLQuery{
		Query: queryAllEntries,
		Variables: map[string]interface{}{
			"rrname":   rrname,
			"rrtype":   rrtype,
			"rdata":    rdata,
			"sensorID": sensorID,
			"limit":    limit,
		},
	}

	if err := c.post(ctx, query, &resp); err != nil {
		return nil, err
	}

	l := EntriesList{}
	if err := json.Unmarshal(resp.Data, &l); err != nil {
		return nil, fmt.Errorf("json decode: %v", err)
	}

	return l.EntriesListItem, nil
}