// SPDX-FileCopyrightText: 2026 Echolot contributors
// SPDX-License-Identifier: GPL-3.0-or-later

package runs

import (
	"encoding/json"
	"errors"
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"
)

func doc(id, anon string) []byte {
	return []byte(fmt.Sprintf(
		`{"run":{"id":%q,"started_at":"2026-08-01T10:00:00Z","privacy":{"anonymization":%q}},`+
			`"findings":[{"id":"f1"},{"id":"f2"}],"summary":{"verdict":"warn"}}`, id, anon))
}

func open(t *testing.T, p Policy) (*Store, string) {
	t.Helper()
	dir := t.TempDir()
	s, err := Open(dir, p)
	if err != nil {
		t.Fatalf("open: %v", err)
	}
	return s, dir
}

func TestModeOffRefusesEverything(t *testing.T) {
	p := DefaultPolicy()
	p.Mode = ModeOff
	s, _ := open(t, p)
	if _, err := s.Put("dev1", doc("run-1", AnonFull), false); !errors.Is(err, ErrDisabled) {
		t.Fatalf("want ErrDisabled, got %v", err)
	}
}

// ModeAccount turns on whether the *caller* has signed in, and nothing else. A device that has
// not is refused with a reason it can act on; one that has is treated exactly like anonymous mode.
func TestModeAccountTurnsOnWhetherTheCallerSignedIn(t *testing.T) {
	p := DefaultPolicy()
	p.Mode = ModeAccount
	s, _ := open(t, p)

	if _, err := s.Put("dev1", doc("run-1", AnonFull), false); !errors.Is(err, ErrNeedAccount) {
		t.Fatalf("an un-signed-in device was not refused: %v", err)
	}
	if _, err := s.Put("dev1", doc("run-2", AnonFull), true); err != nil {
		t.Fatalf("a signed-in device was refused: %v", err)
	}
}

// Signing in must not open a door that the operator closed outright: mode=off means off.
func TestSigningInDoesNotOverrideModeOff(t *testing.T) {
	p := DefaultPolicy()
	p.Mode = ModeOff
	s, _ := open(t, p)
	if _, err := s.Put("dev1", doc("run-1", AnonFull), true); !errors.Is(err, ErrDisabled) {
		t.Fatalf("a signed-in device uploaded to a server with uploads off: %v", err)
	}
}

func TestMinAnonymizationEnforced(t *testing.T) {
	p := DefaultPolicy()
	p.MinAnonymization = AnonBalanced
	s, _ := open(t, p)

	if _, err := s.Put("dev1", doc("run-full", AnonFull), false); !errors.Is(err, ErrNotAnonEnough) {
		t.Fatalf("full should be refused when balanced is required, got %v", err)
	}
	// An undeclared level means nothing was stripped, so it must be treated as "full".
	if _, err := s.Put("dev1", []byte(`{"run":{"id":"run-bare"},"summary":{}}`), false); !errors.Is(err, ErrNotAnonEnough) {
		t.Fatalf("undeclared level should be treated as full, got %v", err)
	}
	for _, lvl := range []string{AnonBalanced, AnonStrict} {
		if _, err := s.Put("dev1", doc("run-"+lvl, lvl), false); err != nil {
			t.Fatalf("%s should be accepted: %v", lvl, err)
		}
	}
}

func TestSizeLimit(t *testing.T) {
	p := DefaultPolicy()
	p.MaxBytes = 200
	s, _ := open(t, p)
	big := append(doc("run-1", AnonFull), make([]byte, 400)...)
	if _, err := s.Put("dev1", big, false); !errors.Is(err, ErrTooLarge) {
		t.Fatalf("want ErrTooLarge, got %v", err)
	}
}

func TestRetentionByCountKeepsNewest(t *testing.T) {
	p := DefaultPolicy()
	p.MaxRunsPerDevice = 3
	s, _ := open(t, p)
	for i := 0; i < 6; i++ {
		if _, err := s.Put("dev1", doc(fmt.Sprintf("run-%d", i), AnonFull), false); err != nil {
			t.Fatalf("put %d: %v", i, err)
		}
		time.Sleep(2 * time.Millisecond) // distinct UploadedAt so "newest" is well defined
	}
	got := s.List("dev1")
	if len(got) != 3 {
		t.Fatalf("kept %d runs, want 3", len(got))
	}
	for i, want := range []string{"run-5", "run-4", "run-3"} {
		if got[i].ID != want {
			t.Fatalf("kept[%d] = %s, want %s (newest first)", i, got[i].ID, want)
		}
	}
	// The documents themselves must be gone too, not just their index entries.
	if _, err := s.Get("dev1", "run-0"); err == nil {
		t.Fatal("purged run is still readable")
	}
}

func TestRetentionByAge(t *testing.T) {
	p := DefaultPolicy()
	p.RetentionDays = 7
	p.MaxRunsPerDevice = 0
	s, dir := open(t, p)
	if _, err := s.Put("dev1", doc("run-old", AnonFull), false); err != nil {
		t.Fatal(err)
	}
	// Backdate the index entry past the retention window.
	metaPath := filepath.Join(dir, "runs", "dev1", "run-old.meta.json")
	b, _ := os.ReadFile(metaPath)
	var m Meta
	_ = json.Unmarshal(b, &m)
	m.UploadedAt = time.Now().Add(-30 * 24 * time.Hour)
	nb, _ := json.Marshal(m)
	if err := os.WriteFile(metaPath, nb, 0o600); err != nil {
		t.Fatal(err)
	}

	if _, err := s.Put("dev1", doc("run-new", AnonFull), false); err != nil {
		t.Fatal(err)
	}
	got := s.List("dev1")
	if len(got) != 1 || got[0].ID != "run-new" {
		t.Fatalf("age retention did not drop the old run: %+v", got)
	}
}

// Run and device ids reach the filesystem, so a hostile one must not be able to climb out of the
// store directory or overwrite another device's data.
func TestIDsCannotEscapeTheStoreDirectory(t *testing.T) {
	s, dir := open(t, DefaultPolicy())
	if _, err := s.Put("../../etc", doc("../../../passwd", AnonFull), false); err != nil {
		t.Fatalf("put: %v", err)
	}
	var found []string
	_ = filepath.Walk(dir, func(p string, info os.FileInfo, err error) error {
		if err == nil && !info.IsDir() {
			rel, _ := filepath.Rel(dir, p)
			found = append(found, filepath.ToSlash(rel))
		}
		return nil
	})
	for _, f := range found {
		if strings.Contains(f, "..") {
			t.Fatalf("path escaped the store: %s", f)
		}
	}
	if len(found) == 0 {
		t.Fatal("nothing written at all")
	}
}

func TestListIsPerDevice(t *testing.T) {
	s, _ := open(t, DefaultPolicy())
	if _, err := s.Put("devA", doc("run-a", AnonFull), false); err != nil {
		t.Fatal(err)
	}
	if _, err := s.Put("devB", doc("run-b", AnonFull), false); err != nil {
		t.Fatal(err)
	}
	if got := s.List("devA"); len(got) != 1 || got[0].ID != "run-a" {
		t.Fatalf("devA sees %+v", got)
	}
	if _, err := s.Get("devA", "run-b"); err == nil {
		t.Fatal("devA could read devB's run")
	}
}

func TestMetaSummarisesTheDocument(t *testing.T) {
	s, _ := open(t, DefaultPolicy())
	m, err := s.Put("dev1", doc("run-1", AnonBalanced), false)
	if err != nil {
		t.Fatal(err)
	}
	if m.FindingCount != 2 || m.Verdict != "warn" || m.Anonymization != AnonBalanced {
		t.Fatalf("meta not extracted: %+v", m)
	}
	if m.StartedAt != "2026-08-01T10:00:00Z" {
		t.Fatalf("started_at = %q", m.StartedAt)
	}
}

func TestMalformedRejected(t *testing.T) {
	s, _ := open(t, DefaultPolicy())
	for _, body := range [][]byte{[]byte("not json"), []byte(`{"run":{}}`), []byte(`{}`)} {
		if _, err := s.Put("dev1", body, false); !errors.Is(err, ErrMalformed) {
			t.Fatalf("body %q: want ErrMalformed, got %v", body, err)
		}
	}
}