package webhook

import (
	"github.com/google/uuid"
	"github.com/jmoiron/sqlx"
	"log"
	"net/http"
	"strings"
	"time"
)

type WebhookService struct {
	DB            *sqlx.DB
	Events        <-chan Event
	Authorization string
}

func (w *WebhookService) Listen() {
	for event := range w.Events {
		webhooks, _ := w.Find()
		var usedWebhooks []Webhook
		for _, webhook := range webhooks {
			usedWebhooks = append(usedWebhooks, webhook)
		}
		w.CreateJobs(usedWebhooks, event)
	}
}

func (w *WebhookService) Run() {
	for {
		jobs, err := w.findRunningJobs()
		if err != nil {
			log.Printf("failed fetching running jobs: %v", err)
		}
		for _, job := range jobs {
			job := w.ExecuteJob(job)
			if err := w.UpdateJob(job); err != nil {
				log.Printf("failed updating job %v: %v", job.Id, err)
			}
		}
		time.Sleep(2 * time.Hour)
	}
}

func (w *WebhookService) Find() ([]Webhook, error) {
	var webhooks []Webhook
	return webhooks, w.DB.Select(&webhooks, `SELECT * FROM "webhook"`)
}

func (w *WebhookService) FindAllJobs() ([]Job, error) {
	var jobs []Job
	return jobs, w.DB.Select(&jobs, `SELECT * FROM "job"`)
}

func (w *WebhookService) FindJobs(webhookId uuid.UUID) ([]Job, error) {
	var jobs []Job
	return jobs, w.DB.Select(&jobs, `SELECT * FROM "job" WHERE id = $1`, webhookId)
}

func (w *WebhookService) findRunningJobs() ([]Job, error) {
	var jobs []Job
	return jobs, w.DB.Select(&jobs, `SELECT * FROM "job" WHERE retry_count > 0 ORDER BY created asc`)
}

func (w *WebhookService) Create(webhook Webhook) (Webhook, error) {
	_, err := w.DB.Exec("INSERT INTO webhook (id, created, url, country, retry_count, on_created, on_edited, on_deleted) VALUES ($1, $2, $3, $4, $5, $6, $7, $8)",
		&webhook.Id, &webhook.Created, &webhook.Url, &webhook.Country, &webhook.RetryCount, &webhook.OnCreated, &webhook.OnEdited, &webhook.OnDeleted,
	)
	return webhook, err
}

func (w *WebhookService) Update(webhook Webhook) (Webhook, error) {
	_, err := w.DB.Exec("UPDATE webhook SET url = $2, country = $3, retry_count = $4, on_created = $5, on_edited = $6, on_deleted = $7 WHERE id = $1",
		&webhook.Id, &webhook.Url, &webhook.Country, &webhook.RetryCount, &webhook.OnCreated, &webhook.OnEdited, &webhook.OnDeleted,
	)
	return webhook, err
}

func (w *WebhookService) CreateJobs(webhooks []Webhook, event Event) {
	json := event.Json()

	tx, _ := w.DB.Begin()
	for _, webhook := range webhooks {
		job := Job{
			Id:          uuid.Must(uuid.NewRandom()),
			WebhookId:   webhook.Id,
			Created:     time.Now(),
			Success:     false,
			SuccessTime: nil,
			RetryCount:  webhook.RetryCount,
			Content:     json,
		}
		_, err := tx.Exec("INSERT INTO job (id, webhook_id, created, success, success_time, retry_count, content) VALUES ($1, $2, $3, $4, $5, $6, $7)",
			&job.Id, &job.WebhookId, &job.Created, &job.Success, &job.SuccessTime, &job.RetryCount, &job.Content,
		)
		if err != nil {
			tx.Rollback()
			return
		}
	}
	tx.Commit()
}

func (w *WebhookService) ExecuteJob(job Job) Job {
	webhook, err := w.FindById(job.WebhookId)
	if err != nil {
		panic(err)
	}
	log.Printf("executing job [%d:%d] %v: POST %s", webhook.RetryCount-job.RetryCount, webhook.RetryCount, job.Id, webhook.Url)
	request, err := http.NewRequest("POST", webhook.Url, strings.NewReader(job.Content))
	request.Header.Add("authorization", "Api "+w.Authorization)

	response, err := http.DefaultClient.Do(request)
	if err != nil || response.StatusCode != http.StatusOK {
		job.RetryCount--
	} else {
		job.Success = true
		currentTime := time.Now()
		job.SuccessTime = &currentTime
	}
	return job
}

func (w *WebhookService) FindById(webhookId uuid.UUID) (Webhook, error) {
	var webhook Webhook
	return webhook, w.DB.Get(&webhook, `SELECT * FROM "webhook" WHERE id = $1`, webhookId)
}

func (w *WebhookService) UpdateJob(job Job) error {
	_, err := w.DB.Exec(`UPDATE job SET success = $2, success_time = $3, retry_count = $4 WHERE id = $1`,
		&job.Id, &job.Success, &job.SuccessTime, &job.RetryCount,
	)
	return err
}

func (w *WebhookService) Delete(webhookId uuid.UUID) error {
	_, err := w.DB.Exec(`DELETE FROM "webhook" WHERE id = $1`,
		&webhookId,
	)
	return err
}