package api

import (
	"database/sql"
	"fmt"
	"log"
	"net/http"
	"strconv"
	"strings"

	"git.hatecomputers.club/hatecomputers/hatecomputers.club/adapters/cloudflare"
	"git.hatecomputers.club/hatecomputers/hatecomputers.club/database"
	"git.hatecomputers.club/hatecomputers/hatecomputers.club/utils"
)

const MAX_USER_RECORDS = 65

type FormError struct {
	Errors []string
}

func userCanFuckWithDNSRecord(dbConn *sql.DB, user *database.User, record *database.DNSRecord) bool {
	ownedByUser := (user.ID == record.UserID)
	if !ownedByUser {
		return false
	}

	if !record.Internal {
		userOwnedDomains := []string{
			fmt.Sprintf("%s", user.Username),
			fmt.Sprintf("%s.endpoints", user.Username),
		}

		for _, domain := range userOwnedDomains {
			isInSubDomain := strings.HasSuffix(record.Name, "."+domain)
			if domain == record.Name || isInSubDomain {
				return true
			}
		}
		return false
	}

	owner, err := database.FindFirstDomainOwnerId(dbConn, record.Name)
	if err != nil {
		log.Println(err)
		return false
	}

	userIsOwnerOfDomain := owner == user.ID
	return ownedByUser && userIsOwnerOfDomain
}

func ListDNSRecordsContinuation(context *RequestContext, req *http.Request, resp http.ResponseWriter) ContinuationChain {
	return func(success Continuation, failure Continuation) ContinuationChain {
		dnsRecords, err := database.GetUserDNSRecords(context.DBConn, context.User.ID)
		if err != nil {
			log.Println(err)
			resp.WriteHeader(http.StatusInternalServerError)
			return failure(context, req, resp)
		}

		(*context.TemplateData)["DNSRecords"] = dnsRecords
		return success(context, req, resp)
	}
}

func CreateDNSRecordContinuation(context *RequestContext, req *http.Request, resp http.ResponseWriter) ContinuationChain {
	return func(success Continuation, failure Continuation) ContinuationChain {
		formErrors := FormError{
			Errors: []string{},
		}

		internal := req.FormValue("internal") == "on"
		name := req.FormValue("name")
		if internal && !strings.HasSuffix(name, ".") {
			name += "."
		}

		recordType := req.FormValue("type")
		recordType = strings.ToUpper(recordType)

		recordContent := req.FormValue("content")
		ttl := req.FormValue("ttl")
		ttlNum, err := strconv.Atoi(ttl)
		if err != nil {
			formErrors.Errors = append(formErrors.Errors, "invalid ttl")
		}

		dnsRecordCount, err := database.CountUserDNSRecords(context.DBConn, context.User.ID)
		if err != nil {
			log.Println(err)
			resp.WriteHeader(http.StatusInternalServerError)
			return failure(context, req, resp)
		}
		if dnsRecordCount >= MAX_USER_RECORDS {
			formErrors.Errors = append(formErrors.Errors, "max records reached")
		}

		dnsRecord := &database.DNSRecord{
			UserID:   context.User.ID,
			Name:     name,
			Type:     recordType,
			Content:  recordContent,
			TTL:      ttlNum,
			Internal: internal,
		}
		if !userCanFuckWithDNSRecord(context.DBConn, context.User, dnsRecord) {
			formErrors.Errors = append(formErrors.Errors, "'name' must end with "+context.User.Username+" or you must be a domain owner for internal domains")
		}

		if len(formErrors.Errors) == 0 {
			if dnsRecord.Internal {
				dnsRecord.ID = utils.RandomId()
			} else {
				cloudflareRecordId, err := cloudflare.CreateDNSRecord(context.Args.CloudflareZone, context.Args.CloudflareToken, dnsRecord)
				if err != nil {
					log.Println(err)
					formErrors.Errors = append(formErrors.Errors, err.Error())
				}

				dnsRecord.ID = cloudflareRecordId
			}
		}

		if len(formErrors.Errors) == 0 {
			_, err := database.SaveDNSRecord(context.DBConn, dnsRecord)
			if err != nil {
				log.Println(err)
				formErrors.Errors = append(formErrors.Errors, "error saving record")
			}
		}

		if len(formErrors.Errors) == 0 {
			http.Redirect(resp, req, "/dns", http.StatusFound)
			return success(context, req, resp)
		}

		(*context.TemplateData)["FormError"] = &formErrors
		(*context.TemplateData)["RecordForm"] = dnsRecord

		resp.WriteHeader(http.StatusBadRequest)
		return failure(context, req, resp)
	}
}

func DeleteDNSRecordContinuation(context *RequestContext, req *http.Request, resp http.ResponseWriter) ContinuationChain {
	return func(success Continuation, failure Continuation) ContinuationChain {
		recordId := req.FormValue("id")
		record, err := database.GetDNSRecord(context.DBConn, recordId)
		if err != nil {
			log.Println(err)
			resp.WriteHeader(http.StatusInternalServerError)
			return failure(context, req, resp)
		}

		if !userCanFuckWithDNSRecord(context.DBConn, context.User, record) {
			resp.WriteHeader(http.StatusUnauthorized)
			return failure(context, req, resp)
		}

		if !record.Internal {
			err = cloudflare.DeleteDNSRecord(context.Args.CloudflareZone, context.Args.CloudflareToken, recordId)
			if err != nil {
				log.Println(err)
				resp.WriteHeader(http.StatusInternalServerError)
				return failure(context, req, resp)
			}
		}

		err = database.DeleteDNSRecord(context.DBConn, recordId)
		if err != nil {
			resp.WriteHeader(http.StatusInternalServerError)
			return failure(context, req, resp)
		}

		http.Redirect(resp, req, "/dns", http.StatusFound)
		return success(context, req, resp)
	}
}