package main

import (
	"bytes"
	"encoding/csv"
	"encoding/json"
	"fmt"
	"io"
	"log"
	"net/http"
	"os"
	"sort"
	"strconv"
	"time"
)

const apiURL = "https://api.cloudflare.com/client/v4"

var apiKey string

type Zone struct {
	ID   string `json:"id"`
	Name string `json:"name"`
}

type Record struct {
	ID            string    `json:"id"`
	ZoneID        string    `json:"zone_id"`
	ZoneName      string    `json:"zone_name"`
	Name          string    `json:"name"`
	Type          string    `json:"type"`
	Content       string    `json:"content"`
	Proxiable     bool      `json:"proxiable"`
	Proxied       bool      `json:"proxied"`
	TTL           int       `json:"ttl"`
	Comment       string    `json:"comment"`
	Tags          []string  `json:"tags"`
	CreatedOn     time.Time `json:"created_on"`
	ModifiedOn    time.Time `json:"modified_on"`
	NumberQueries int
}

type ZoneResult struct {
	Result []Zone `json:"result"`
}

type RecordResult struct {
	Result []Record `json:"result"`
}

type Analytic struct {
	Result struct {
		Rows int `json:"rows"`
		Data []struct {
			Metrics []int `json:"metrics"`
		} `json:"data"`
		DataLag int `json:"data_lag"`
		Min     struct {
		} `json:"min"`
		Max struct {
		} `json:"max"`
		Totals struct {
			QueryCount int `json:"queryCount"`
		} `json:"totals"`
		Query struct {
			Dimensions []any     `json:"dimensions"`
			Metrics    []string  `json:"metrics"`
			Since      time.Time `json:"since"`
			Until      time.Time `json:"until"`
			Limit      int       `json:"limit"`
		} `json:"query"`
	} `json:"result"`
}

func main() {
	apiKey = os.Getenv("cfapikey")

	zones, err := getZones()
	if err != nil {
		log.Fatalf("failed to get zones: %v", err)
	}

	outRows := make([]Record, 0)

	for _, zone := range zones {
		log.Printf("processing zone '%s' with ID '%s'", zone.Name, zone.ID)

		records, err := getRecords(zone)
		if err != nil {
			log.Printf("failed to get records for zone '%s' with ID '%s': %v", zone.Name, zone.ID, err)
		}

		for _, record := range records {
			analytic, err := getRecordAnalytic(zone, record)
			if err != nil {
				log.Printf("failed to get record report for record '%s' in zone '%s' with ID '%s': %v", record.Name, zone.Name, zone.ID, err)
				continue
			}
			record.NumberQueries = analytic.Result.Totals.QueryCount
			outRows = append(outRows, record)
		}
	}

	sort.Slice(outRows, func(i, j int) bool {
		return outRows[i].NumberQueries < outRows[j].NumberQueries
	})

	buf := bytes.NewBuffer(nil)
	writer := csv.NewWriter(buf)
	writer.Write([]string{"Name", "Type", "NumberQueries", "CreatedOn", "ModifiedOn", "Comment", "Content"})

	for _, row := range outRows {
		writer.Write([]string{row.Name, row.Type, strconv.Itoa(row.NumberQueries), row.CreatedOn.Format(time.RFC3339), row.ModifiedOn.Format(time.RFC3339), row.Comment, row.Content})
	}
	writer.Flush()

	b, err := io.ReadAll(buf)
	if err != nil {
		log.Fatalf("failed to read bytes from output buffer: %v", err)
	}

	fmt.Println(string(b))

}

func getZones() ([]Zone, error) {
	req, err := http.NewRequest("GET", fmt.Sprintf("%s/zones", apiURL), nil)
	if err != nil {
		return nil, fmt.Errorf("failed to create new http request: %v", err)
	}
	req.Header.Add("Content-Type", "application/json")
	//req.Header.Add("X-Auth-Email", apiKey)
	req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", apiKey))

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to execute http request: %v", err)
	}

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("http response has status '%d' but expected '%d'", resp.StatusCode, http.StatusOK)
	}

	b, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read http response body: %v", err)
	}
	zoneResult := &ZoneResult{}

	err = json.Unmarshal(b, zoneResult)
	if err != nil {
		return nil, fmt.Errorf("failed to unmarshal response body to struct: %v", err)
	}

	return zoneResult.Result, nil
}

func getRecords(zone Zone) ([]Record, error) {
	req, err := http.NewRequest("GET", fmt.Sprintf("%s/zones/%s/dns_records", apiURL, zone.ID), nil)
	if err != nil {
		return nil, fmt.Errorf("failed to create new http request: %v", err)
	}
	req.Header.Add("Content-Type", "application/json")
	//req.Header.Add("X-Auth-Email", apiKey)
	req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", apiKey))

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to execute http request: %v", err)
	}

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("http response has status '%d' but expected '%d'", resp.StatusCode, http.StatusOK)
	}

	b, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read http response body: %v", err)
	}
	recordResult := &RecordResult{}

	err = json.Unmarshal(b, recordResult)
	if err != nil {
		return nil, fmt.Errorf("failed to unmarshal response body to struct: %v", err)
	}

	return recordResult.Result, nil
}

func getRecordAnalytic(zone Zone, record Record) (*Analytic, error) {
	req, err := http.NewRequest("GET", fmt.Sprintf("%s/zones/%s/dns_analytics/report", apiURL, zone.ID), nil)
	if err != nil {
		return nil, fmt.Errorf("failed to create new http request: %v", err)
	}
	req.Header.Add("Content-Type", "application/json")
	//req.Header.Add("X-Auth-Email", apiKey)
	req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", apiKey))

	q := req.URL.Query()
	q.Add("filters", fmt.Sprintf("queryName==%s", record.Name))
	//q.Add("filters", fmt.Sprintf("queryName==%s,queryType==%s", record.Name, record.Type))
	req.URL.RawQuery = q.Encode()

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return nil, fmt.Errorf("failed to execute http request: %v", err)
	}

	if resp.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("http response has status '%d' but expected '%d'", resp.StatusCode, http.StatusOK)
	}

	b, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, fmt.Errorf("failed to read http response body: %v", err)
	}

	analytic := &Analytic{}

	err = json.Unmarshal(b, analytic)
	if err != nil {
		return nil, fmt.Errorf("failed to unmarshal response body to struct: %v", err)
	}

	return analytic, nil

}