use crate::{AgentTool, ToolCallEventStream};
use agent_client_protocol::ToolKind;
use anyhow::{Context as _, Result, anyhow};
use gpui::{App, AppContext, Entity, SharedString, Task};
use project::Project;
use schemars::JsonSchema;
use serde::{Deserialize, Serialize};
use std::sync::Arc;
use util::markdown::MarkdownInlineCode;

/// Copies a file or directory in the project, and returns confirmation that the
/// copy succeeded.
///
/// Directory contents will be copied recursively (like `cp -r`).
///
/// This tool should be used when it's desirable to create a copy of a file or
/// directory without modifying the original. It's much more efficient than
/// doing this by separately reading and then writing the file or directory's
/// contents, so this tool should be preferred over that approach whenever
/// copying is the goal.
#[derive(Debug, Serialize, Deserialize, JsonSchema)]
pub struct CopyPathToolInput {
    /// The source path of the file or directory to copy.
    /// If a directory is specified, its contents will be copied recursively (like `cp -r`).
    ///
    /// <example>
    /// If the project has the following files:
    ///
    /// - directory1/a/something.txt
    /// - directory2/a/things.txt
    /// - directory3/a/other.txt
    ///
    /// You can copy the first file by providing a source_path of "directory1/a/something.txt"
    /// </example>
    pub source_path: String,

    /// The destination path where the file or directory should be copied to.
    ///
    /// <example>
    /// To copy "directory1/a/something.txt" to "directory2/b/copy.txt",
    /// provide a destination_path of "directory2/b/copy.txt"
    /// </example>
    pub destination_path: String,
}

pub struct CopyPathTool {
    project: Entity<Project>,
}

impl CopyPathTool {
    pub fn new(project: Entity<Project>) -> Self {
        Self { project }
    }
}

impl AgentTool for CopyPathTool {
    type Input = CopyPathToolInput;
    type Output = String;

    fn name(&self) -> SharedString {
        "copy_path".into()
    }

    fn kind(&self) -> ToolKind {
        ToolKind::Move
    }

    fn initial_title(&self, input: Result<Self::Input, serde_json::Value>) -> ui::SharedString {
        if let Ok(input) = input {
            let src = MarkdownInlineCode(&input.source_path);
            let dest = MarkdownInlineCode(&input.destination_path);
            format!("Copy {src} to {dest}").into()
        } else {
            "Copy path".into()
        }
    }

    fn run(
        self: Arc<Self>,
        input: Self::Input,
        _event_stream: ToolCallEventStream,
        cx: &mut App,
    ) -> Task<Result<Self::Output>> {
        let copy_task = self.project.update(cx, |project, cx| {
            match project
                .find_project_path(&input.source_path, cx)
                .and_then(|project_path| project.entry_for_path(&project_path, cx))
            {
                Some(entity) => match project.find_project_path(&input.destination_path, cx) {
                    Some(project_path) => {
                        project.copy_entry(entity.id, None, project_path.path, cx)
                    }
                    None => Task::ready(Err(anyhow!(
                        "Destination path {} was outside the project.",
                        input.destination_path
                    ))),
                },
                None => Task::ready(Err(anyhow!(
                    "Source path {} was not found in the project.",
                    input.source_path
                ))),
            }
        });

        cx.background_spawn(async move {
            let _ = copy_task.await.with_context(|| {
                format!(
                    "Copying {} to {}",
                    input.source_path, input.destination_path
                )
            })?;
            Ok(format!(
                "Copied {} to {}",
                input.source_path, input.destination_path
            ))
        })
    }
}