File Ops

"""Helpers for tracking file operations and computing diffs for CLI display."""

from future import annotations

import difflib from dataclasses import dataclass, field from pathlib import Path from typing import TYPE_CHECKING, Any, Literal

from deepagents.backends.utils import perform_string_replacement

from deepagents_cli.config import settings

if TYPE_CHECKING: from deepagents.backends.protocol import BACKEND_TYPES

FileOpStatus = Literal["pending", "success", "error"]

@dataclass class ApprovalPreview: """Data used to render HITL previews."""

title: str
details: list[str]
diff: str | None = None
diff_title: str | None = None
error: str | None = None

def _safe_read(path: Path) -> str | None: """Read file content, returning None on failure.""" try: return path.read_text() except (OSError, UnicodeDecodeError): return None

def _count_lines(text: str) -> int: """Count lines in text, treating empty strings as zero lines.""" if not text: return 0 return len(text.splitlines())

def compute_unified_diff( before: str, after: str, display_path: str, *, max_lines: int | None = 800, context_lines: int = 3, ) -> str | None: """Compute a unified diff between before and after content.

Args:
    before: Original content
    after: New content
    display_path: Path for display in diff headers
    max_lines: Maximum number of diff lines (None for unlimited)
    context_lines: Number of context lines around changes (default 3)

Returns:
    Unified diff string or None if no changes
"""
before_lines = before.splitlines()
after_lines = after.splitlines()
diff_lines = list(
    difflib.unified_diff(
        before_lines,
        after_lines,
        fromfile=f"{display_path} (before)",
        tofile=f"{display_path} (after)",
        lineterm="",
        n=context_lines,
    )
)
if not diff_lines:
    return None
if max_lines is not None and len(diff_lines) > max_lines:
    truncated = diff_lines[: max_lines - 1]
    truncated.append("...")
    return "\n".join(truncated)
return "\n".join(diff_lines)

@dataclass class FileOpMetrics: """Line and byte level metrics for a file operation."""

lines_read: int = 0
start_line: int | None = None
end_line: int | None = None
lines_written: int = 0
lines_added: int = 0
lines_removed: int = 0
bytes_written: int = 0

@dataclass class FileOperationRecord: """Track a single filesystem tool call."""

tool_name: str
display_path: str
physical_path: Path | None
tool_call_id: str | None
args: dict[str, Any] = field(default_factory=dict)
status: FileOpStatus = "pending"
error: str | None = None
metrics: FileOpMetrics = field(default_factory=FileOpMetrics)
diff: str | None = None
before_content: str | None = None
after_content: str | None = None
read_output: str | None = None
hitl_approved: bool = False

def resolve_physical_path(path_str: str | None, assistant_id: str | None) -> Path | None: """Convert a virtual/​relative path to a physical filesystem path.""" if not path_str: return None try: if assistant_id and path_str.startswith("/​memories/"): agent_dir = settings.get_agent_dir(assistant_id) suffix = path_str.removeprefix("/​memories/").lstrip("/") return (agent_dir / suffix).resolve() path = Path(path_str) if path.is_absolute(): return path return (Path.cwd() / path).resolve() except (OSError, ValueError): return None

def format_display_path(path_str: str | None) -> str: """Format a path for display.""" if not path_str: return "(unknown)" try: path = Path(path_str) if path.is_absolute(): return path.name or str(path) return str(path) except (OSError, ValueError): return str(path_str)

def build_approval_preview( tool_name: str, args: dict[str, Any], assistant_id: str | None, ) -> ApprovalPreview | None: """Collect summary info and diff for HITL approvals.""" path_str = str(args.get("file_path") or args.get("path") or "") display_path = format_display_path(path_str) physical_path = resolve_physical_path(path_str, assistant_id)

if tool_name == "write_file":
    content = str(args.get("content", ""))
    before = _safe_read(physical_path) if physical_path and physical_path.exists() else ""
    after = content
    diff = compute_unified_diff(before or "", after, display_path, max_lines=100)
    additions = 0
    if diff:
        additions = sum(
            1
            for line in diff.splitlines()
            if line.startswith("+") and not line.startswith("+++")
        )
    total_lines = _count_lines(after)
    details = [
        f"File: {path_str}",
        "Action: Create new file" + (" (overwrites existing content)" if before else ""),
        f"Lines to write: {additions or total_lines}",
    ]
    return ApprovalPreview(
        title=f"Write {display_path}",
        details=details,
        diff=diff,
        diff_title=f"Diff {display_path}",
    )

if tool_name == "edit_file":
    if physical_path is None:
        return ApprovalPreview(
            title=f"Update {display_path}",
            details=[f"File: {path_str}", "Action: Replace text"],
            error="Unable to resolve file path.",
        )
    before = _safe_read(physical_path)
    if before is None:
        return ApprovalPreview(
            title=f"Update {display_path}",
            details=[f"File: {path_str}", "Action: Replace text"],
            error="Unable to read current file contents.",
        )
    old_string = str(args.get("old_string", ""))
    new_string = str(args.get("new_string", ""))
    replace_all = bool(args.get("replace_all", False))
    replacement = perform_string_replacement(before, old_string, new_string, replace_all)
    if isinstance(replacement, str):
        return ApprovalPreview(
            title=f"Update {display_path}",
            details=[f"File: {path_str}", "Action: Replace text"],
            error=replacement,
        )
    after, occurrences = replacement
    diff = compute_unified_diff(before, after, display_path, max_lines=None)
    additions = 0
    deletions = 0
    if diff:
        additions = sum(
            1
            for line in diff.splitlines()
            if line.startswith("+") and not line.startswith("+++")
        )
        deletions = sum(
            1
            for line in diff.splitlines()
            if line.startswith("-") and not line.startswith("---")
        )
    details = [
        f"File: {path_str}",
        f"Action: Replace text ({'all occurrences' if replace_all else 'single occurrence'})",
        f"Occurrences matched: {occurrences}",
        f"Lines changed: +{additions} / -{deletions}",
    ]
    return ApprovalPreview(
        title=f"Update {display_path}",
        details=details,
        diff=diff,
        diff_title=f"Diff {display_path}",
    )

return None

class FileOpTracker: """Collect file operation metrics during a CLI interaction."""

def __init__(self, *, assistant_id: str | None, backend: BACKEND_TYPES | None = None) -> None:
    """Initialize the tracker."""
    self.assistant_id = assistant_id
    self.backend = backend
    self.active: dict[str | None, FileOperationRecord] = {}
    self.completed: list[FileOperationRecord] = []

def start_operation(
    self, tool_name: str, args: dict[str, Any], tool_call_id: str | None
) -> None:
    if tool_name not in {"read_file", "write_file", "edit_file"}:
        return
    path_str = str(args.get("file_path") or args.get("path") or "")
    display_path = format_display_path(path_str)
    record = FileOperationRecord(
        tool_name=tool_name,
        display_path=display_path,
        physical_path=resolve_physical_path(path_str, self.assistant_id),
        tool_call_id=tool_call_id,
        args=args,
    )
    if tool_name in {"write_file", "edit_file"}:
        if self.backend and path_str:
            try:
                responses = self.backend.download_files([path_str])
                if (
                    responses
                    and responses[0].content is not None
                    and responses[0].error is None
                ):
                    record.before_content = responses[0].content.decode("utf-8")
                else:
                    record.before_content = ""
            except Exception:
                record.before_content = ""
        elif record.physical_path:
            record.before_content = _safe_read(record.physical_path) or ""
    self.active[tool_call_id] = record

def update_args(self, tool_call_id: str, args: dict[str, Any]) -> None:
    """Update arguments for an active operation and retry capturing before_content."""
    record = self.active.get(tool_call_id)
    if not record:
        return

    record.args.update(args)

    # If we haven't captured before_content yet, try again now that we might have the path
    if record.before_content is None and record.tool_name in {"write_file", "edit_file"}:
        path_str = str(record.args.get("file_path") or record.args.get("path") or "")
        if path_str:
            record.display_path = format_display_path(path_str)
            record.physical_path = resolve_physical_path(path_str, self.assistant_id)
            if self.backend:
                try:
                    responses = self.backend.download_files([path_str])
                    if (
                        responses
                        and responses[0].content is not None
                        and responses[0].error is None
                    ):
                        record.before_content = responses[0].content.decode("utf-8")
                    else:
                        record.before_content = ""
                except Exception:
                    record.before_content = ""
            elif record.physical_path:
                record.before_content = _safe_read(record.physical_path) or ""

def complete_with_message(self, tool_message: Any) -> FileOperationRecord | None:
    tool_call_id = getattr(tool_message, "tool_call_id", None)
    record = self.active.get(tool_call_id)
    if record is None:
        return None

    content = tool_message.content
    if isinstance(content, list):
        # Some tool messages may return list segments; join them for analysis.
        joined = []
        for item in content:
            if isinstance(item, str):
                joined.append(item)
            else:
                joined.append(str(item))
        content_text = "\n".join(joined)
    else:
        content_text = str(content) if content is not None else ""

    if getattr(
        tool_message, "status", "success"
    ) != "success" or content_text.lower().startswith("error"):
        record.status = "error"
        record.error = content_text
        self._finalize(record)
        return record

    record.status = "success"

    if record.tool_name == "read_file":
        record.read_output = content_text
        lines = _count_lines(content_text)
        record.metrics.lines_read = lines
        offset = record.args.get("offset")
        limit = record.args.get("limit")
        if isinstance(offset, int):
            if offset > lines:
                offset = 0
            record.metrics.start_line = offset + 1
            if lines:
                record.metrics.end_line = offset + lines
        elif lines:
            record.metrics.start_line = 1
            record.metrics.end_line = lines
        if isinstance(limit, int) and lines > limit:
            record.metrics.end_line = (record.metrics.start_line or 1) + limit - 1
    else:
        # For write/​edit operations, read back from backend (or local filesystem)
        self._populate_after_content(record)
        if record.after_content is None:
            record.status = "error"
            record.error = "Could not read updated file content."
            self._finalize(record)
            return record
        record.metrics.lines_written = _count_lines(record.after_content)
        before_lines = _count_lines(record.before_content or "")
        diff = compute_unified_diff(
            record.before_content or "",
            record.after_content,
            record.display_path,
            max_lines=100,
        )
        record.diff = diff
        if diff:
            additions = sum(
                1
                for line in diff.splitlines()
                if line.startswith("+") and not line.startswith("+++")
            )
            deletions = sum(
                1
                for line in diff.splitlines()
                if line.startswith("-") and not line.startswith("---")
            )
            record.metrics.lines_added = additions
            record.metrics.lines_removed = deletions
        elif record.tool_name == "write_file" and (record.before_content or "") == "":
            record.metrics.lines_added = record.metrics.lines_written
        record.metrics.bytes_written = len(record.after_content.encode("utf-8"))
        if record.diff is None and (record.before_content or "") != record.after_content:
            record.diff = compute_unified_diff(
                record.before_content or "",
                record.after_content,
                record.display_path,
                max_lines=100,
            )
        if record.diff is None and before_lines != record.metrics.lines_written:
            record.metrics.lines_added = max(record.metrics.lines_written - before_lines, 0)

    self._finalize(record)
    return record

def mark_hitl_approved(self, tool_name: str, args: dict[str, Any]) -> None:
    """Mark operations matching tool_name and file_path as HIL-approved."""
    file_path = args.get("file_path") or args.get("path")
    if not file_path:
        return

    # Mark all active records that match
    for record in self.active.values():
        if record.tool_name == tool_name:
            record_path = record.args.get("file_path") or record.args.get("path")
            if record_path == file_path:
                record.hitl_approved = True

def _populate_after_content(self, record: FileOperationRecord) -> None:
    # Use backend if available (works for any BackendProtocol implementation)
    if self.backend:
        try:
            file_path = record.args.get("file_path") or record.args.get("path")
            if file_path:
                responses = self.backend.download_files([file_path])
                if (
                    responses
                    and responses[0].content is not None
                    and responses[0].error is None
                ):
                    record.after_content = responses[0].content.decode("utf-8")
                else:
                    record.after_content = None
            else:
                record.after_content = None
        except Exception:
            record.after_content = None
    else:
        # Fallback: direct filesystem read when no backend provided
        if record.physical_path is None:
            record.after_content = None
            return
        record.after_content = _safe_read(record.physical_path)

def _finalize(self, record: FileOperationRecord) -> None:
    self.completed.append(record)
    self.active.pop(record.tool_call_id, None)