package service

import (
	"bytes"
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"net/url"
	"strings"
	"testing"
)

// clientForHandler returns an http.Client that routes requests to the given handler
// without real network sockets.
func clientForHandler(h http.Handler) *http.Client {
	return &http.Client{
		Transport: roundTripperFunc(func(req *http.Request) (*http.Response, error) {
			// Clone request body for handler
			var bodyBytes []byte
			if req.Body != nil {
				bodyBytes, _ = io.ReadAll(req.Body)
			}
			r := httptest.NewRequest(req.Method, req.URL.String(), bytes.NewReader(bodyBytes))
			r.Header = req.Header.Clone()

			w := httptest.NewRecorder()
			h.ServeHTTP(w, r)
			return w.Result(), nil
		}),
	}
}

type roundTripperFunc func(req *http.Request) (*http.Response, error)

func (f roundTripperFunc) RoundTrip(req *http.Request) (*http.Response, error) { return f(req) }

func TestUpdateUserPassword_Success(t *testing.T) {
	const (
		loginID     = "user@example.com"
		identityID  = "7f0dc8c3-9d5d-4f57-b3d1-123456789abc"
		newPassword = "Sup3rStr0ng!Pass#2026"
	)

	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		switch {
		case strings.HasPrefix(r.URL.Path, "/admin/identities") && r.Method == http.MethodGet:
			q := r.URL.Query()
			if got := q.Get("credentials_identifier"); got != loginID {
				t.Fatalf("expected credentials_identifier=%s, got=%s", loginID, got)
			}
			_ = json.NewEncoder(w).Encode([]map[string]string{
				{"id": identityID},
			})
			return
		case r.URL.Path == "/admin/identities/"+identityID && r.Method == http.MethodPatch:
			body, _ := io.ReadAll(r.Body)
			if !strings.Contains(string(body), newPassword) {
				t.Fatalf("payload missing new password, body=%s", string(body))
			}
			w.WriteHeader(http.StatusOK)
			return
		default:
			t.Fatalf("unexpected request: %s %s", r.Method, r.URL.String())
		}
	})

	provider := &OryProvider{
		KratosAdminURL: "http://kratos-admin.local",
		HTTPClient:     clientForHandler(handler),
	}

	if err := provider.UpdateUserPassword(loginID, newPassword, nil); err != nil {
		t.Fatalf("UpdateUserPassword returned error: %v", err)
	}
}

func TestUpdateUserPassword_NotFound(t *testing.T) {
	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if strings.HasPrefix(r.URL.Path, "/admin/identities") && r.Method == http.MethodGet {
			http.NotFound(w, r)
			return
		}
		t.Fatalf("unexpected request: %s %s", r.Method, r.URL.String())
	})

	provider := &OryProvider{
		KratosAdminURL: "http://kratos-admin.local",
		HTTPClient:     clientForHandler(handler),
	}

	err := provider.UpdateUserPassword("user@example.com", "Sup3rStr0ng!Pass#2026", nil)
	if err == nil || !strings.Contains(err.Error(), "identity not found") {
		t.Fatalf("expected identity not found error, got: %v", err)
	}
}

func TestUpdateUserPassword_ServerError(t *testing.T) {
	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		switch {
		case strings.HasPrefix(r.URL.Path, "/admin/identities") && r.Method == http.MethodGet:
			_ = json.NewEncoder(w).Encode([]map[string]string{
				{"id": "abc"},
			})
			return
		case r.URL.Path == "/admin/identities/abc" && r.Method == http.MethodPatch:
			http.Error(w, "boom", http.StatusInternalServerError)
			return
		default:
			t.Fatalf("unexpected request: %s %s", r.Method, r.URL.String())
		}
	})

	provider := &OryProvider{
		KratosAdminURL: "http://kratos-admin.local",
		HTTPClient:     clientForHandler(handler),
	}

	err := provider.UpdateUserPassword("user@example.com", "Sup3rStr0ng!Pass#2026", nil)
	if err == nil || !strings.Contains(err.Error(), "password update failed") {
		t.Fatalf("expected server error, got: %v", err)
	}
}

func TestFindIdentityID_QueryEncoding(t *testing.T) {
	loginID := "user+alias@example.com"
	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		values, _ := url.ParseQuery(r.URL.RawQuery)
		if values.Get("credentials_identifier") != loginID {
			t.Fatalf("expected credentials_identifier=%s, got=%s", loginID, values.Get("credentials_identifier"))
		}
		_ = json.NewEncoder(w).Encode([]map[string]string{
			{"id": "id-123"},
		})
	})

	provider := &OryProvider{
		KratosAdminURL: "http://kratos-admin.local",
		HTTPClient:     clientForHandler(handler),
	}

	id, err := provider.findIdentityID(loginID)
	if err != nil {
		t.Fatalf("findIdentityID returned error: %v", err)
	}
	if id != "id-123" {
		t.Fatalf("expected id-123, got %s", id)
	}
}