mobius 0.9.21

use diffy::DiffOptions;
use serde::Deserialize;
use serde_json::Value;

use super::patch::{apply_patch_document, parse_patch_document};
use super::{
    ApprovalRequirement, ExecutionMode, HookIdentity, MAX_MUTATION_BYTES, MAX_TOOL_OUTPUT_BYTES,
    Tool, ToolContext, ToolExposure, text,
};
use crate::backend::model::ToolDefinition;
use crate::{BoxFuture, Error, Result};

#[derive(Deserialize)]
struct PathArgs {
    path: String,
}

pub(super) struct ReadFile;

impl Tool for ReadFile {
    fn definition(&self) -> ToolDefinition {
        ToolDefinition {
            name: "read_file".into(),
            description: text::TOOL_READ_FILE_DESCRIPTION.into(),
            parameters: serde_json::json!({
                "type": "object",
                "properties": {
                    "path": {
                        "type": "string",
                        "description": text::TOOL_READ_FILE_PARAMETER_PATH_DESCRIPTION
                    }
                },
                "required": ["path"],
                "additionalProperties": false
            }),
        }
    }

    fn exposure(&self) -> ToolExposure {
        ToolExposure::Direct
    }

    fn execution_mode(&self) -> ExecutionMode {
        ExecutionMode::Parallel
    }

    fn call<'a>(&'a self, context: ToolContext, arguments: Value) -> BoxFuture<'a, Result<String>> {
        Box::pin(async move {
            let arguments: PathArgs = serde_json::from_value(arguments)?;
            context.sandbox.read(&arguments.path).await
        })
    }
}

#[derive(Deserialize)]
struct WriteArgs {
    path: String,
    content: String,
}

pub(super) struct WriteFile;

impl Tool for WriteFile {
    fn definition(&self) -> ToolDefinition {
        ToolDefinition {
            name: "write_file".into(),
            description: text::TOOL_WRITE_FILE_DESCRIPTION.into(),
            parameters: serde_json::json!({
                "type": "object",
                "properties": {
                    "path": {"type": "string"},
                    "content": {"type": "string"}
                },
                "required": ["path", "content"],
                "additionalProperties": false
            }),
        }
    }

    fn exposure(&self) -> ToolExposure {
        ToolExposure::Direct
    }

    fn approval(&self) -> ApprovalRequirement {
        ApprovalRequirement::Always
    }

    fn call<'a>(&'a self, context: ToolContext, arguments: Value) -> BoxFuture<'a, Result<String>> {
        Box::pin(async move {
            let arguments: WriteArgs = serde_json::from_value(arguments)?;
            if arguments.content.len() > MAX_MUTATION_BYTES {
                return Err(Error::Tool(format!(
                    "content exceeds {MAX_MUTATION_BYTES} bytes"
                )));
            }
            context
                .sandbox
                .write(&arguments.path, &arguments.content, &context.permissions)
                .await?;
            Ok(format!(
                "wrote {} bytes to {}",
                arguments.content.len(),
                arguments.path
            ))
        })
    }
}

#[derive(Deserialize)]
#[serde(deny_unknown_fields)]
pub(super) struct ApplyPatchArgs {
    patch: String,
}

pub(super) struct ApplyPatch;

impl Tool for ApplyPatch {
    fn definition(&self) -> ToolDefinition {
        ToolDefinition {
            name: "apply_patch".into(),
            description: text::TOOL_APPLY_PATCH_DESCRIPTION.into(),
            parameters: serde_json::json!({
                "type": "object",
                "properties": {
                    "patch": {
                        "type": "string",
                        "description": text::TOOL_APPLY_PATCH_PARAMETER_PATCH_DESCRIPTION
                    }
                },
                "required": ["patch"],
                "additionalProperties": false
            }),
        }
    }

    fn exposure(&self) -> ToolExposure {
        ToolExposure::Direct
    }

    fn approval(&self) -> ApprovalRequirement {
        ApprovalRequirement::Always
    }

    fn hook_identity(&self) -> Option<HookIdentity> {
        Some(HookIdentity {
            name: "apply_patch",
            subjects: &["apply_patch", "Edit", "Write"],
        })
    }

    fn hook_input(&self, arguments: &Value) -> Value {
        serde_json::json!({
            "command": arguments.get("patch").cloned().unwrap_or(Value::Null)
        })
    }

    fn rewrite_hook_input(&self, input: Value) -> Result<Value> {
        let command = input
            .get("command")
            .and_then(Value::as_str)
            .ok_or_else(|| Error::Config("hook tool rewrite requires `command`".into()))?;
        Ok(serde_json::json!({"patch": command}))
    }

    fn call<'a>(&'a self, context: ToolContext, arguments: Value) -> BoxFuture<'a, Result<String>> {
        Box::pin(async move {
            let arguments: ApplyPatchArgs = serde_json::from_value(arguments)?;
            if arguments.patch.len() > MAX_MUTATION_BYTES {
                return Err(Error::Tool(format!(
                    "patch exceeds {MAX_MUTATION_BYTES} bytes"
                )));
            }
            let document = parse_patch_document(&arguments.patch)?;
            let content = context.sandbox.read(&document.path).await?;
            let updated = apply_patch_document(&content, &document)?;
            if updated == content {
                return Err(Error::Tool(
                    "Patch rejected: patch applies but makes no changes.".into(),
                ));
            }
            let mut options = DiffOptions::new();
            options
                .set_original_filename(document.path.clone())
                .set_modified_filename(document.path.clone());
            let diff = options.create_patch(&content, &updated).to_string();
            context
                .sandbox
                .write(&document.path, &updated, &context.permissions)
                .await?;
            Ok(if diff.len() <= MAX_TOOL_OUTPUT_BYTES {
                diff
            } else {
                format!("patched {} (diff too large to display)", document.path)
            })
        })
    }
}