feat: Sync Strava rides as GPX files

1 files changed, 146 insertions, 0 deletions

diff --git a/strava/strava.go b/strava/strava.go
new file mode 100644
index 0000000..d394791
--- /dev/null
+++ b/strava/strava.go
@@ -0,0 +1,146 @@
+package strava
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"time"
+
+	"github.com/martinlehoux/kagamigo/kcore"
+)
+
+const (
+	AuthURL   = "https://www.strava.com/oauth/authorize"
+	TokenURL  = "https://www.strava.com/oauth/token"
+	APIURL    = "https://www.strava.com/api/v3"
+	LoginPort = 8787
+)
+
+var (
+	tokenEndpoint = TokenURL
+	apiEndpoint   = APIURL
+)
+
+type Token struct {
+	AccessToken  string
+	RefreshToken string
+	ExpiresAt    time.Time
+}
+
+func AuthorizeURL(clientID, redirectURI string) string {
+	q := url.Values{}
+	q.Set("client_id", clientID)
+	q.Set("response_type", "code")
+	q.Set("redirect_uri", redirectURI)
+	q.Set("approval_prompt", "auto")
+	q.Set("scope", "activity:read_all")
+	return AuthURL + "?" + q.Encode()
+}
+
+type tokenResponse struct {
+	AccessToken  string `json:"access_token"`
+	RefreshToken string `json:"refresh_token"`
+	ExpiresAt    int64  `json:"expires_at"`
+}
+
+func ExchangeCode(clientID, clientSecret, code, redirectURI string) (Token, error) {
+	form := url.Values{}
+	form.Set("client_id", clientID)
+	form.Set("client_secret", clientSecret)
+	form.Set("code", code)
+	form.Set("grant_type", "authorization_code")
+	form.Set("redirect_uri", redirectURI)
+	return requestToken(form)
+}
+
+func Refresh(clientID, clientSecret, refreshToken string) (Token, error) {
+	form := url.Values{}
+	form.Set("client_id", clientID)
+	form.Set("client_secret", clientSecret)
+	form.Set("grant_type", "refresh_token")
+	form.Set("refresh_token", refreshToken)
+	return requestToken(form)
+}
+
+func requestToken(form url.Values) (Token, error) {
+	resp, err := http.PostForm(tokenEndpoint, form)
+	if err != nil {
+		return Token{}, kcore.Wrap(err, "failed to request Strava token")
+	}
+	defer resp.Body.Close()
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return Token{}, kcore.Wrap(err, "failed to read Strava token response")
+	}
+	if resp.StatusCode != http.StatusOK {
+		return Token{}, fmt.Errorf("strava token request failed (HTTP %d): %s", resp.StatusCode, body)
+	}
+	var parsed tokenResponse
+	if err := json.Unmarshal(body, &parsed); err != nil {
+		return Token{}, kcore.Wrap(err, "failed to decode Strava token response")
+	}
+	if parsed.AccessToken == "" {
+		return Token{}, fmt.Errorf("strava token response missing access_token: %s", body)
+	}
+	return Token{
+		AccessToken:  parsed.AccessToken,
+		RefreshToken: parsed.RefreshToken,
+		ExpiresAt:    time.Unix(parsed.ExpiresAt, 0),
+	}, nil
+}
+
+type Client struct {
+	ClientID     string
+	ClientSecret string
+	HTTP         *http.Client
+	tokens       Token
+}
+
+func NewClient(clientID, clientSecret string, tokens Token) *Client {
+	return &Client{ClientID: clientID, ClientSecret: clientSecret, HTTP: http.DefaultClient, tokens: tokens}
+}
+
+func (c *Client) Tokens() Token {
+	return c.tokens
+}
+
+func (c *Client) RefreshIfNeeded() (bool, error) {
+	if time.Until(c.tokens.ExpiresAt) > 5*time.Minute {
+		return false, nil
+	}
+	refreshed, err := Refresh(c.ClientID, c.ClientSecret, c.tokens.RefreshToken)
+	if err != nil {
+		return false, kcore.Wrap(err, "failed to refresh Strava access token")
+	}
+	c.tokens = refreshed
+	return true, nil
+}
+
+func (c *Client) GetJSON(path string, out any) error {
+	if _, err := c.RefreshIfNeeded(); err != nil {
+		return err
+	}
+	req, err := http.NewRequest(http.MethodGet, apiEndpoint+path, nil)
+	if err != nil {
+		return kcore.Wrap(err, "failed to build Strava request")
+	}
+	req.Header.Set("Authorization", "Bearer "+c.tokens.AccessToken)
+	resp, err := c.HTTP.Do(req)
+	if err != nil {
+		return kcore.Wrap(err, "failed to call Strava API")
+	}
+	defer resp.Body.Close()
+	body, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return kcore.Wrap(err, "failed to read Strava API response")
+	}
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("strava API %s failed (HTTP %d): %s", path, resp.StatusCode, body)
+	}
+	if err := json.Unmarshal(body, out); err != nil {
+		return kcore.Wrap(err, "failed to decode Strava API response")
+	}
+	return nil
+}