write.go

  1package tools
  2
  3import (
  4	"context"
  5	_ "embed"
  6	"fmt"
  7	"log/slog"
  8	"os"
  9	"path/filepath"
 10	"strings"
 11	"time"
 12
 13	"charm.land/fantasy"
 14	"github.com/charmbracelet/crush/internal/csync"
 15	"github.com/charmbracelet/crush/internal/diff"
 16	"github.com/charmbracelet/crush/internal/filepathext"
 17	"github.com/charmbracelet/crush/internal/fsext"
 18	"github.com/charmbracelet/crush/internal/history"
 19
 20	"github.com/charmbracelet/crush/internal/lsp"
 21	"github.com/charmbracelet/crush/internal/permission"
 22)
 23
 24//go:embed write.md
 25var writeDescription []byte
 26
 27type WriteParams struct {
 28	FilePath string `json:"file_path" description:"The path to the file to write"`
 29	Content  string `json:"content" description:"The content to write to the file"`
 30}
 31
 32type WritePermissionsParams struct {
 33	FilePath   string `json:"file_path"`
 34	OldContent string `json:"old_content,omitempty"`
 35	NewContent string `json:"new_content,omitempty"`
 36}
 37
 38type writeTool struct {
 39	lspClients  *csync.Map[string, *lsp.Client]
 40	permissions permission.Service
 41	files       history.Service
 42	workingDir  string
 43}
 44
 45type WriteResponseMetadata struct {
 46	Diff      string `json:"diff"`
 47	Additions int    `json:"additions"`
 48	Removals  int    `json:"removals"`
 49}
 50
 51const WriteToolName = "write"
 52
 53func NewWriteTool(lspClients *csync.Map[string, *lsp.Client], permissions permission.Service, files history.Service, workingDir string) fantasy.AgentTool {
 54	return fantasy.NewAgentTool(
 55		WriteToolName,
 56		string(writeDescription),
 57		func(ctx context.Context, params WriteParams, call fantasy.ToolCall) (fantasy.ToolResponse, error) {
 58			if params.FilePath == "" {
 59				return fantasy.NewTextErrorResponse("file_path is required"), nil
 60			}
 61
 62			if params.Content == "" {
 63				return fantasy.NewTextErrorResponse("content is required"), nil
 64			}
 65
 66			filePath := filepathext.SmartJoin(workingDir, params.FilePath)
 67
 68			fileInfo, err := os.Stat(filePath)
 69			if err == nil {
 70				if fileInfo.IsDir() {
 71					return fantasy.NewTextErrorResponse(fmt.Sprintf("Path is a directory, not a file: %s", filePath)), nil
 72				}
 73
 74				modTime := fileInfo.ModTime()
 75				lastRead := getLastReadTime(filePath)
 76				if modTime.After(lastRead) {
 77					return fantasy.NewTextErrorResponse(fmt.Sprintf("File %s has been modified since it was last read.\nLast modification: %s\nLast read: %s\n\nPlease read the file again before modifying it.",
 78						filePath, modTime.Format(time.RFC3339), lastRead.Format(time.RFC3339))), nil
 79				}
 80
 81				oldContent, readErr := os.ReadFile(filePath)
 82				if readErr == nil && string(oldContent) == params.Content {
 83					return fantasy.NewTextErrorResponse(fmt.Sprintf("File %s already contains the exact content. No changes made.", filePath)), nil
 84				}
 85			} else if !os.IsNotExist(err) {
 86				return fantasy.ToolResponse{}, fmt.Errorf("error checking file: %w", err)
 87			}
 88
 89			dir := filepath.Dir(filePath)
 90			if err = os.MkdirAll(dir, 0o755); err != nil {
 91				return fantasy.ToolResponse{}, fmt.Errorf("error creating directory: %w", err)
 92			}
 93
 94			oldContent := ""
 95			if fileInfo != nil && !fileInfo.IsDir() {
 96				oldBytes, readErr := os.ReadFile(filePath)
 97				if readErr == nil {
 98					oldContent = string(oldBytes)
 99				}
100			}
101
102			sessionID := GetSessionFromContext(ctx)
103			if sessionID == "" {
104				return fantasy.ToolResponse{}, fmt.Errorf("session_id is required")
105			}
106
107			diff, additions, removals := diff.GenerateDiff(
108				oldContent,
109				params.Content,
110				strings.TrimPrefix(filePath, workingDir),
111			)
112
113			granted, err := CheckHookPermission(ctx, permissions, permission.CreatePermissionRequest{
114				SessionID:   sessionID,
115				Path:        fsext.PathOrPrefix(filePath, workingDir),
116				ToolCallID:  call.ID,
117				ToolName:    WriteToolName,
118				Action:      "write",
119				Description: fmt.Sprintf("Create file %s", filePath),
120				Params: WritePermissionsParams{
121					FilePath:   filePath,
122					OldContent: oldContent,
123					NewContent: params.Content,
124				},
125			})
126			if err != nil {
127				return fantasy.ToolResponse{}, err
128			}
129			if !granted {
130				return fantasy.ToolResponse{}, permission.ErrorPermissionDenied
131			}
132
133			err = os.WriteFile(filePath, []byte(params.Content), 0o644)
134			if err != nil {
135				return fantasy.ToolResponse{}, fmt.Errorf("error writing file: %w", err)
136			}
137
138			// Check if file exists in history
139			file, err := files.GetByPathAndSession(ctx, filePath, sessionID)
140			if err != nil {
141				_, err = files.Create(ctx, sessionID, filePath, oldContent)
142				if err != nil {
143					// Log error but don't fail the operation
144					return fantasy.ToolResponse{}, fmt.Errorf("error creating file history: %w", err)
145				}
146			}
147			if file.Content != oldContent {
148				// User Manually changed the content store an intermediate version
149				_, err = files.CreateVersion(ctx, sessionID, filePath, oldContent)
150				if err != nil {
151					slog.Debug("Error creating file history version", "error", err)
152				}
153			}
154			// Store the new version
155			_, err = files.CreateVersion(ctx, sessionID, filePath, params.Content)
156			if err != nil {
157				slog.Debug("Error creating file history version", "error", err)
158			}
159
160			recordFileWrite(filePath)
161			recordFileRead(filePath)
162
163			notifyLSPs(ctx, lspClients, params.FilePath)
164
165			result := fmt.Sprintf("File successfully written: %s", filePath)
166			result = fmt.Sprintf("<result>\n%s\n</result>", result)
167			result += getDiagnostics(filePath, lspClients)
168			return fantasy.WithResponseMetadata(fantasy.NewTextResponse(result),
169				WriteResponseMetadata{
170					Diff:      diff,
171					Additions: additions,
172					Removals:  removals,
173				},
174			), nil
175		})
176}