package server

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

	"git.t-juice.club/microfilm/users"
	"go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
	"go.opentelemetry.io/otel"
)

type UserClient struct {
	BaseURL string
	client  *http.Client
}

const defaultTimeout time.Duration = 5 * time.Second

func NewUserClient(baseurl string) *UserClient {
	return &UserClient{
		BaseURL: baseurl,
		client: &http.Client{
			Transport: otelhttp.NewTransport(http.DefaultTransport),
		},
	}
}

func (c *UserClient) VerifyUserPassword(ctx context.Context, username, password string) error {
	ctx, span := otel.GetTracerProvider().Tracer("").Start(ctx, "verify-user-password")
	defer span.End()

	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
	defer cancel()

	url := fmt.Sprintf("%s/%s/verify", c.BaseURL, username)
	body := struct {
		Password string `json:"password"`
	}{
		Password: password,
	}
	var buf bytes.Buffer

	enc := json.NewEncoder(&buf)
	if err := enc.Encode(&body); err != nil {
		return err
	}
	req, err := http.NewRequestWithContext(ctx, http.MethodPost, url, &buf)
	if err != nil {
		return err
	}

	resp, err := c.client.Do(req)
	if err != nil {
		return err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("authentication failed")
	}

	return nil
}

func (c *UserClient) GetUser(ctx context.Context, identifier string) (users.User, error) {
	var u users.User

	ctx, span := otel.GetTracerProvider().Tracer("").Start(ctx, "get-user")
	defer span.End()

	ctx, cancel := context.WithTimeout(ctx, defaultTimeout)
	defer cancel()

	url := fmt.Sprintf("%s/%s", c.BaseURL, identifier)

	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url, nil)
	if err != nil {
		return u, err
	}

	resp, err := c.client.Do(req)
	if err != nil {
		return u, err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return u, fmt.Errorf("authentication failed")
	}

	decoder := json.NewDecoder(resp.Body)
	if err := decoder.Decode(&u); err != nil {
		return u, err
	}

	return u, nil
}