package mcpserver

import (
	"bytes"
	"context"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"strings"
	"time"
)

const (
	requestTimeout  = 60 * time.Second
	maxResponseSize = 8 << 20
)

type Client struct {
	baseURL string
	apiKey  string
	http    *http.Client
}

type Response struct {
	Status int
	Body   string
}

func NewClient(baseURL string, apiKey string, httpClient *http.Client) *Client {
	if httpClient == nil {
		httpClient = &http.Client{Timeout: requestTimeout}
	}
	return &Client{baseURL: strings.TrimRight(baseURL, "/"), apiKey: apiKey, http: httpClient}
}

func (c *Client) Do(ctx context.Context, method string, path string, query url.Values, body []byte, contentType string) (Response, error) {
	target := c.baseURL + path
	if len(query) > 0 {
		target += "?" + query.Encode()
	}
	req, err := http.NewRequestWithContext(ctx, method, target, bytes.NewReader(body))
	if err != nil {
		return Response{}, err
	}
	if c.apiKey != "" {
		req.Header.Set("Authorization", "Bearer "+c.apiKey)
	}
	if contentType != "" {
		req.Header.Set("Content-Type", contentType)
	}
	res, err := c.http.Do(req)
	if err != nil {
		return Response{}, err
	}
	defer res.Body.Close()
	raw, err := io.ReadAll(io.LimitReader(res.Body, maxResponseSize))
	if err != nil {
		return Response{}, err
	}
	return Response{Status: res.StatusCode, Body: string(raw)}, nil
}

func (r Response) Failed() bool {
	return r.Status < 200 || r.Status > 299
}

func (r Response) Describe() string {
	text := strings.TrimSpace(r.Body)
	if r.Status == http.StatusNoContent || text == "" {
		return fmt.Sprintf("HTTP %d", r.Status)
	}
	if r.Failed() {
		return fmt.Sprintf("HTTP %d: %s", r.Status, text)
	}
	return text
}