package emapi

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"strings"
	"time"

	"go.uber.org/zap"

	"go.equinixmetal.net/infra9-metal-bridge/internal/metal/providers"
)

const (
	defaultHTTPTimeout = 20 * time.Second
	defaultBaseURL     = "https://api.equinix.com/metal/v1"

	authHeader       = "X-Auth-Token"
	consumerHeader   = "X-Consumer-Token"
	staffHeader      = "X-Packet-Staff"
	staffHeaderValue = "true"
)

var DefaultHTTPClient = &http.Client{
	Timeout: defaultHTTPTimeout,
}

var _ providers.Provider = &Client{}

type Client struct {
	logger        *zap.SugaredLogger
	httpClient    *http.Client
	baseURL       *url.URL
	authToken     string
	consumerToken string
}

func (c *Client) Do(req *http.Request, out any) (*http.Response, error) {
	if c.authToken != "" {
		req.Header.Set(authHeader, c.authToken)
	}

	if c.consumerToken != "" {
		req.Header.Set(consumerHeader, c.consumerToken)
	}

	if c.authToken != "" && c.consumerToken != "" {
		req.Header.Set(staffHeader, staffHeaderValue)
	}

	resp, err := c.httpClient.Do(req)
	if err != nil {
		return nil, err
	}

	if out != nil {
		defer resp.Body.Close()

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

	return resp, nil
}

func (c *Client) DoRequest(ctx context.Context, method, path string, body io.Reader, out any) (*http.Response, error) {
	path = strings.TrimPrefix(path, c.baseURL.Path)

	pathURL, err := url.Parse(path)
	if err != nil {
		return nil, err
	}

	url := c.baseURL.JoinPath(pathURL.Path)

	query := url.Query()

	for k, v := range pathURL.Query() {
		query[k] = v
	}

	url.RawQuery = query.Encode()

	req, err := http.NewRequestWithContext(ctx, method, url.String(), body)
	if err != nil {
		return nil, fmt.Errorf("failed to build request: %w", err)
	}

	resp, err := c.Do(req, out)
	if err != nil {
		return nil, fmt.Errorf("failed to get response: %w", err)
	}

	if resp.StatusCode < http.StatusOK || resp.StatusCode >= http.StatusMultipleChoices {
		return resp, fmt.Errorf("unexpected status code: %d", resp.StatusCode)
	}

	return resp, nil
}

// New creates a new emapi client
func New(options ...Option) (*Client, error) {
	client := &Client{}

	for _, opt := range options {
		if err := opt(client); err != nil {
			return nil, err
		}
	}

	if client.logger == nil {
		client.logger = zap.NewNop().Sugar()
	}

	if client.httpClient == nil {
		client.httpClient = DefaultHTTPClient
	}

	if client.baseURL == nil {
		u, err := url.Parse(defaultBaseURL)
		if err != nil {
			return nil, fmt.Errorf("failed to parse emapi base url %s: %w", defaultBaseURL, err)
		}

		client.baseURL = u
	}

	return client, nil
}