package gitea

import (
	"net/http"
	"time"

	"gitea.com/gitea/gitea-mcp/pkg/debug"
	"gitea.com/gitea/gitea-mcp/pkg/flag"
	"gitea.com/gitea/gitea-mcp/pkg/log"

	"go.uber.org/zap"
)

// loggingRoundTripper wraps an http.RoundTripper to emit one structured log
// entry per upstream Gitea API call when debug is enabled. The information
// here is much more useful for diagnosing slow / failing tool calls than the
// gitea SDK's built-in debug mode (which only writes a separate, free-form
// stream that doesn't merge with the zap log file).
//
// We log:
//   - method, URL (with sensitive query params stripped)
//   - request_id from the request context (when the caller propagated one)
//   - HTTP status code (or transport-level error)
//   - duration in milliseconds
//   - response Content-Length when the server provided one
//
// We deliberately do NOT log request or response bodies — those routinely
// contain user secrets (tokens being created, webhook payloads, file
// contents) and the log file is meant to be safe to share.
type loggingRoundTripper struct {
	base http.RoundTripper
}

func (rt *loggingRoundTripper) RoundTrip(req *http.Request) (*http.Response, error) {
	if !flag.DebugScopeEnabled("http") {
		return rt.base.RoundTrip(req)
	}

	start := time.Now()
	resp, err := rt.base.RoundTrip(req)
	duration := time.Since(start)

	fields := []zap.Field{
		zap.String("method", req.Method),
		zap.String("url", debug.StripQueryTokens(req.URL.String())),
		zap.Int64("duration_ms", duration.Milliseconds()),
	}
	if reqID := debug.RequestIDFromContext(req.Context()); reqID != "" {
		fields = append(fields, zap.String("request_id", reqID))
	}
	if toolName := debug.ToolNameFromContext(req.Context()); toolName != "" {
		fields = append(fields, zap.String("tool", toolName))
	}

	if err != nil {
		fields = append(fields, zap.String("error", err.Error()))
		log.Debug("gitea http: transport error", fields...)
		return resp, err
	}

	fields = append(fields,
		zap.Int("status", resp.StatusCode),
		zap.Int64("bytes_in", resp.ContentLength),
	)
	log.Debug("gitea http: response", fields...)
	return resp, nil
}