// operation_log_test.go -- 统一操作日志的单元测试.
//
// 覆盖场景:
//   - Record 记录操作
//   - GetByMessage 按消息查询
//   - RollbackMessage 按消息回滚(倒序执行 Undo)
//   - 不可逆操作跳过
//   - 无 UndoInfo 的操作跳过
package engine

import (
	"context"
	"encoding/json"
	"errors"
	"testing"

	"git.flytoex.net/yuanwei/flyto-agent/pkg/tools"
)

// ─────────────────────────────────────────────────────────────────────
// Mock UndoExecutor
// ─────────────────────────────────────────────────────────────────────

type mockUndoExecutor struct {
	executed []*tools.UndoInfo
	failOn   string // 如果 ToolName 匹配这个值,返回错误
}

func (m *mockUndoExecutor) ExecuteUndo(ctx context.Context, undo *tools.UndoInfo) error {
	if undo.ToolName == m.failOn {
		return errors.New("mock undo failed")
	}
	m.executed = append(m.executed, undo)
	return nil
}

// ─────────────────────────────────────────────────────────────────────
// 测试
// ─────────────────────────────────────────────────────────────────────

func TestOperationLog_Record(t *testing.T) {
	log := NewOperationLog(&NoopObserver{})

	log.Record(&OperationEntry{
		ID:        "op-1",
		MessageID: "msg-1",
		ToolName:  "Edit",
		Status:    "success",
	})

	if log.EntryCount() != 1 {
		t.Errorf("应该有 1 条记录，实际: %d", log.EntryCount())
	}
}

// TestOperationLog_Record_PreservesTruncation asserts Truncated /
// StoredPath survive Record + GetByMessage round-trip so audit consumers
// walking the log can find the authoritative full result. Without this
// wire, summary-only Output would be treated as the record of truth.
//
// TestOperationLog_Record_PreservesTruncation 断言 Truncated / StoredPath
// 经 Record + GetByMessage 往返后仍在, 走 OperationLog 的审计消费者才能找
// 到权威完整结果. 没这条 wire, summary-only 的 Output 会被当作权威记录.
func TestOperationLog_Record_PreservesTruncation(t *testing.T) {
	log := NewOperationLog(&NoopObserver{})

	log.Record(&OperationEntry{
		ID:         "op-trunc",
		MessageID:  "msg-1",
		ToolName:   "Bash",
		Output:     "[truncated: 300/10485760 bytes]",
		Status:     "success",
		Truncated:  true,
		StoredPath: "/tmp/flyto/results/op-trunc.txt",
	})

	entries := log.GetByMessage("msg-1")
	if len(entries) != 1 {
		t.Fatalf("GetByMessage len = %d, want 1", len(entries))
	}
	got := entries[0]
	if !got.Truncated {
		t.Errorf("Truncated lost on round-trip; got false")
	}
	if got.StoredPath != "/tmp/flyto/results/op-trunc.txt" {
		t.Errorf("StoredPath = %q, want /tmp/flyto/results/op-trunc.txt", got.StoredPath)
	}
}

func TestOperationLog_GetByMessage(t *testing.T) {
	log := NewOperationLog(&NoopObserver{})

	log.Record(&OperationEntry{ID: "op-1", MessageID: "msg-1", ToolName: "Edit"})
	log.Record(&OperationEntry{ID: "op-2", MessageID: "msg-2", ToolName: "Write"})
	log.Record(&OperationEntry{ID: "op-3", MessageID: "msg-1", ToolName: "Grep"})

	entries := log.GetByMessage("msg-1")
	if len(entries) != 2 {
		t.Errorf("msg-1 应该有 2 条操作，实际: %d", len(entries))
	}

	entries = log.GetByMessage("msg-2")
	if len(entries) != 1 {
		t.Errorf("msg-2 应该有 1 条操作，实际: %d", len(entries))
	}

	entries = log.GetByMessage("msg-999")
	if len(entries) != 0 {
		t.Errorf("msg-999 应该没有操作，实际: %d", len(entries))
	}
}

func TestOperationLog_RollbackMessage(t *testing.T) {
	log := NewOperationLog(&NoopObserver{})
	executor := &mockUndoExecutor{}

	log.Record(&OperationEntry{
		ID: "op-1", MessageID: "msg-1", ToolName: "Edit", Status: "success",
		Input: json.RawMessage(`{"file_path": "a.txt"}`),
		UndoInfo: &tools.UndoInfo{
			ToolName:    "Write",
			Input:       map[string]any{"file_path": "a.txt"},
			Description: "恢复 a.txt",
		},
	})
	log.Record(&OperationEntry{
		ID: "op-2", MessageID: "msg-1", ToolName: "Write", Status: "success",
		Input: json.RawMessage(`{"file_path": "b.txt"}`),
		UndoInfo: &tools.UndoInfo{
			ToolName:    "Write",
			Input:       map[string]any{"file_path": "b.txt"},
			Description: "恢复 b.txt",
		},
	})

	err := log.RollbackMessage(context.Background(), "msg-1", executor)
	if err != nil {
		t.Fatalf("回滚不应失败: %v", err)
	}

	// 应该倒序执行:先 op-2,再 op-1
	if len(executor.executed) != 2 {
		t.Fatalf("应该执行 2 次 undo，实际: %d", len(executor.executed))
	}
	if executor.executed[0].Input["file_path"] != "b.txt" {
		t.Errorf("第一个 undo 应该是 b.txt（倒序），实际: %v", executor.executed[0].Input)
	}
	if executor.executed[1].Input["file_path"] != "a.txt" {
		t.Errorf("第二个 undo 应该是 a.txt（倒序），实际: %v", executor.executed[1].Input)
	}
}

func TestOperationLog_RollbackMessage_SkipNoUndo(t *testing.T) {
	log := NewOperationLog(&NoopObserver{})
	executor := &mockUndoExecutor{}

	log.Record(&OperationEntry{
		ID: "op-1", MessageID: "msg-1", ToolName: "Grep", Status: "success",
		// 无 UndoInfo(只读工具)
	})
	log.Record(&OperationEntry{
		ID: "op-2", MessageID: "msg-1", ToolName: "Edit", Status: "success",
		UndoInfo: &tools.UndoInfo{ToolName: "Write", Description: "恢复"},
	})

	err := log.RollbackMessage(context.Background(), "msg-1", executor)
	if err != nil {
		t.Fatalf("回滚不应失败: %v", err)
	}

	// 只有 op-2 有 UndoInfo,所以只执行 1 次
	if len(executor.executed) != 1 {
		t.Errorf("应该只执行 1 次 undo，实际: %d", len(executor.executed))
	}
}

func TestOperationLog_RollbackMessage_SkipIrreversible(t *testing.T) {
	log := NewOperationLog(&NoopObserver{})
	executor := &mockUndoExecutor{}

	log.Record(&OperationEntry{
		ID: "op-1", MessageID: "msg-1", ToolName: "Bash", Status: "success",
		UndoInfo: &tools.UndoInfo{
			Irreversible: true,
			ManualGuide:  "请手动检查 bash 命令的副作用",
		},
	})

	err := log.RollbackMessage(context.Background(), "msg-1", executor)
	if err != nil {
		t.Fatalf("回滚不应失败: %v", err)
	}

	// 不可逆操作应该被跳过
	if len(executor.executed) != 0 {
		t.Errorf("不可逆操作不应执行 undo，实际执行了: %d", len(executor.executed))
	}
}

func TestOperationLog_RollbackMessage_NotFound(t *testing.T) {
	log := NewOperationLog(&NoopObserver{})
	executor := &mockUndoExecutor{}

	err := log.RollbackMessage(context.Background(), "msg-999", executor)
	if err == nil {
		t.Error("回滚不存在的消息应该返回错误")
	}
}

func TestOperationLog_RollbackMessage_BestEffort(t *testing.T) {
	log := NewOperationLog(&NoopObserver{})
	executor := &mockUndoExecutor{failOn: "FailTool"}

	log.Record(&OperationEntry{
		ID: "op-1", MessageID: "msg-1", ToolName: "Edit", Status: "success",
		UndoInfo: &tools.UndoInfo{ToolName: "Write", Description: "恢复 a.txt"},
	})
	log.Record(&OperationEntry{
		ID: "op-2", MessageID: "msg-1", ToolName: "Custom", Status: "success",
		UndoInfo: &tools.UndoInfo{ToolName: "FailTool", Description: "会失败的 undo"},
	})
	log.Record(&OperationEntry{
		ID: "op-3", MessageID: "msg-1", ToolName: "Edit", Status: "success",
		UndoInfo: &tools.UndoInfo{ToolName: "Write", Description: "恢复 b.txt"},
	})

	// 即使 op-2 的 undo 失败,op-1 和 op-3 的 undo 仍应执行
	err := log.RollbackMessage(context.Background(), "msg-1", executor)
	// 应该返回最后一个错误
	if err == nil {
		t.Error("应该返回错误（因为 op-2 的 undo 失败了）")
	}

	// op-3 和 op-1 的 undo 应该成功执行
	if len(executor.executed) != 2 {
		t.Errorf("应该执行 2 次 undo（跳过失败的），实际: %d", len(executor.executed))
	}
}