pocket_cli/vcs/

remote.rs

//! Remote functionality for Pocket VCS
//!
//! Handles interaction with remote repositories.

use std::path::PathBuf;
use std::collections::HashMap;
use serde::{Serialize, Deserialize};
use anyhow::{Result, anyhow};
use thiserror::Error;
use url::Url;
use std::fs;

use crate::vcs::{ShoveId, Timeline, Repository, ObjectId, Tree, Shove};
use crate::vcs::objects::EntryType;

/// Error types specific to remote operations
#[derive(Error, Debug)]
pub enum RemoteError {
    #[error("Remote already exists: {0}")]
    AlreadyExists(String),
    
    #[error("Remote not found: {0}")]
    NotFound(String),
    
    #[error("Authentication failed: {0}")]
    AuthenticationFailed(String),
    
    #[error("Network error: {0}")]
    NetworkError(String),
    
    #[error("Remote rejected operation: {0}")]
    RemoteRejected(String),
}

/// Remote tracking information
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct RemoteTracking {
    /// Name of the remote
    pub remote_name: String,
    
    /// Name of the remote timeline
    pub remote_timeline: String,
    
    /// Last known remote shove ID
    pub last_known_shove: Option<ShoveId>,
}

/// A remote repository
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Remote {
    /// Name of the remote
    pub name: String,
    
    /// URL of the remote
    pub url: String,
    
    /// Authentication information (if any)
    pub auth: Option<RemoteAuth>,
    
    /// Fetch refspec
    pub fetch_refspec: String,
    
    /// Push refspec
    pub push_refspec: String,
}

/// Authentication information for a remote
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum RemoteAuth {
    /// No authentication
    None,
    
    /// Basic authentication (username/password)
    Basic {
        username: String,
        password: String,
    },
    
    /// SSH key authentication
    SshKey {
        username: String,
        key_path: PathBuf,
    },
    
    /// Token authentication
    Token {
        token: String,
    },
}

/// Remote manager for handling remote operations
pub struct RemoteManager<'a> {
    /// Repository to operate on
    pub repo: &'a Repository,
    
    /// Remotes, keyed by name
    pub remotes: HashMap<String, Remote>,
}

impl<'a> RemoteManager<'a> {
    /// Create a new remote manager
    pub fn new(repo: &'a Repository) -> Result<Self> {
        // Load remotes from repository
        let remotes = Self::load_remotes(repo)?;
        
        Ok(Self { repo, remotes })
    }
    
    /// Load remotes from the repository
    fn load_remotes(repo: &Repository) -> Result<HashMap<String, Remote>> {
        // This is a placeholder for the actual implementation
        // A real implementation would load remotes from the repository config
        
        // For now, just return an empty map
        Ok(HashMap::new())
    }
    
    /// Add a new remote
    pub fn add_remote(&mut self, name: &str, url: &str) -> Result<()> {
        // Check if remote already exists
        if self.remotes.contains_key(name) {
            return Err(RemoteError::AlreadyExists(name.to_string()).into());
        }
        
        // Parse URL
        let url_parsed = Url::parse(url)?;
        
        // Create remote
        let remote = Remote {
            name: name.to_string(),
            url: url.to_string(),
            auth: None,
            fetch_refspec: format!("timelines/*:timelines/{}/remote/*", name),
            push_refspec: format!("timelines/*:timelines/*"),
        };
        
        // Add to map
        self.remotes.insert(name.to_string(), remote);
        
        // Save remotes
        self.save_remotes()?;
        
        Ok(())
    }
    
    /// Remove a remote
    pub fn remove_remote(&mut self, name: &str) -> Result<()> {
        // Check if remote exists
        if !self.remotes.contains_key(name) {
            return Err(RemoteError::NotFound(name.to_string()).into());
        }
        
        // Remove from map
        self.remotes.remove(name);
        
        // Save remotes
        self.save_remotes()?;
        
        Ok(())
    }
    
    /// Save remotes to the repository
    fn save_remotes(&self) -> Result<()> {
        // This is a placeholder for the actual implementation
        // A real implementation would save remotes to the repository config
        
        // For now, just return Ok
        Ok(())
    }
    
    /// Push changes to a remote repository
    pub fn push(&self, remote_name: &str, timeline_name: &str) -> Result<()> {
        // Get the remote
        let remote = self.remotes.get(remote_name)
            .ok_or_else(|| RemoteError::NotFound(remote_name.to_string()))?;
        
        // Get the timeline
        let timeline_path = self.repo.path.join(".pocket").join("timelines").join(format!("{}.toml", timeline_name));
        let timeline = Timeline::load(&timeline_path)?;
        
        // Check if we have a head to push
        let head = timeline.head.as_ref()
            .ok_or_else(|| anyhow!("Timeline has no commits to push"))?;
        
        // Prepare the URL for the push operation
        let push_url = format!("{}/push", remote.url);
        
        println!("Pushing to remote '{}' ({})", remote_name, remote.url);
        
        // Collect all objects that need to be pushed
        let objects = self.collect_objects_to_push(head)?;
        println!("Collected {} objects to push", objects.len());
        
        // In a real implementation, we would:
        // 1. Establish a connection to the remote
        // 2. Authenticate using the remote.auth information
        // 3. Send the objects
        // 4. Update the remote reference
        
        // For now, we'll simulate a successful push
        println!("Successfully pushed {} to {}/{}", timeline_name, remote_name, timeline_name);
        
        // Update the remote tracking information
        let mut timeline = Timeline::load(&timeline_path)?;
        timeline.set_remote_tracking(remote_name, timeline_name);
        timeline.save(&timeline_path)?;
        
        Ok(())
    }
    
    /// Pull changes from a remote repository
    pub fn pull(&self, remote_name: &str, timeline_name: &str) -> Result<()> {
        // Get the remote
        let remote = self.remotes.get(remote_name)
            .ok_or_else(|| RemoteError::NotFound(remote_name.to_string()))?;
        
        // Prepare the URL for the pull operation
        let pull_url = format!("{}/pull", remote.url);
        
        println!("Pulling from remote '{}' ({})", remote_name, remote.url);
        
        // In a real implementation, we would:
        // 1. Establish a connection to the remote
        // 2. Authenticate using the remote.auth information
        // 3. Fetch the remote timeline information
        // 4. Download new objects
        // 5. Update the local timeline
        
        // For now, we'll simulate a successful pull with no new changes
        println!("Remote is up to date. Nothing to pull.");
        
        Ok(())
    }
    
    /// Fetch changes from a remote repository without merging
    pub fn fetch(&self, remote_name: &str) -> Result<()> {
        // Get the remote
        let remote = self.remotes.get(remote_name)
            .ok_or_else(|| RemoteError::NotFound(remote_name.to_string()))?;
        
        // Prepare the URL for the fetch operation
        let fetch_url = format!("{}/fetch", remote.url);
        
        println!("Fetching from remote '{}' ({})", remote_name, remote.url);
        
        // In a real implementation, we would:
        // 1. Establish a connection to the remote
        // 2. Authenticate using the remote.auth information
        // 3. Fetch the remote timeline information
        // 4. Download new objects
        // 5. Update the remote tracking references
        
        // For now, we'll simulate a successful fetch with no new changes
        println!("Remote is up to date. Nothing to fetch.");
        
        Ok(())
    }
    
    /// Collect all objects that need to be pushed to a remote
    fn collect_objects_to_push(&self, head: &ShoveId) -> Result<Vec<ObjectId>> {
        let mut objects = Vec::new();
        let mut visited = std::collections::HashSet::new();
        let mut to_visit = vec![head.clone()];
        
        while let Some(shove_id) = to_visit.pop() {
            // Skip if already visited
            if visited.contains(&shove_id) {
                continue;
            }
            
            // Mark as visited
            visited.insert(shove_id.clone());
            
            // Load the shove
            let shove_path = self.repo.path.join(".pocket").join("shoves").join(format!("{}.toml", shove_id.as_str()));
            let shove_content = fs::read_to_string(&shove_path)?;
            let shove: Shove = toml::from_str(&shove_content)?;
            
            // Add the shove's tree object
            objects.push(shove.root_tree_id.clone());
            
            // Add the tree's objects recursively
            self.collect_tree_objects(&shove.root_tree_id, &mut objects)?;
            
            // Add parent shoves to visit
            for parent_id in shove.parent_ids {
                to_visit.push(parent_id);
            }
        }
        
        Ok(objects)
    }
    
    /// Recursively collect all objects in a tree
    fn collect_tree_objects(&self, tree_id: &ObjectId, objects: &mut Vec<ObjectId>) -> Result<()> {
        // Load the tree
        let tree_path = self.repo.path.join(".pocket").join("objects").join(tree_id.as_str());
        let tree_content = fs::read_to_string(&tree_path)?;
        let tree: Tree = toml::from_str(&tree_content)?;
        
        // Add all entries
        for entry in tree.entries {
            objects.push(entry.id.clone());
            
            // If this is a tree, recurse
            if entry.entry_type == EntryType::Tree {
                self.collect_tree_objects(&entry.id, objects)?;
            }
        }
        
        Ok(())
    }
    
    // Additional methods would be implemented here:
    // - list_remotes: List all remotes
    // - get_remote: Get a specific remote
    // - set_remote_url: Change the URL of a remote
    // - etc.
}