kodegen_tools_github 0.1.3

use kodegen_mcp_tool::{McpError, Tool};
use kodegen_mcp_schema::github::CreateOrUpdateFileArgs;
use serde_json::Value;
use rmcp::model::{PromptArgument, PromptMessage, PromptMessageRole, PromptMessageContent};
use anyhow;

use crate::GitHubClient;
use crate::github::CreateOrUpdateFileRequest;

/// Tool for creating a new file or updating an existing file
pub struct CreateOrUpdateFileTool;

impl Tool for CreateOrUpdateFileTool {
    type Args = CreateOrUpdateFileArgs;
    type PromptArgs = ();

    fn name() -> &'static str {
        "create_or_update_file"
    }

    fn description() -> &'static str {
        "Create a new file or update an existing file in a GitHub repository"
    }

    fn read_only() -> bool {
        false
    }

    fn destructive() -> bool {
        false
    }

    fn idempotent() -> bool {
        false
    }

    fn open_world() -> bool {
        true
    }

    async fn execute(&self, args: Self::Args) -> Result<Value, McpError> {
        let token = std::env::var("GITHUB_TOKEN")
            .map_err(|_| McpError::Other(anyhow::anyhow!(
                "GITHUB_TOKEN environment variable not set"
            )))?;

        let client = GitHubClient::builder()
            .personal_token(token)
            .build()
            .map_err(|e| McpError::Other(anyhow::anyhow!("Failed to create GitHub client: {}", e)))?;

        let request = CreateOrUpdateFileRequest {
            owner: args.owner,
            repo: args.repo,
            path: args.path,
            message: args.message,
            content: args.content,
            branch: args.branch,
            sha: args.sha,
        };

        let task_result = client
            .create_or_update_file(request)
            .await;

        let api_result = task_result
            .map_err(|e| McpError::Other(anyhow::anyhow!("Task channel error: {}", e)))?;

        let file_update = api_result
            .map_err(|e| McpError::Other(anyhow::anyhow!("GitHub API error: {}", e)))?;

        Ok(serde_json::to_value(&file_update)?)
    }

    async fn prompt(&self, _args: Self::PromptArgs) -> Result<Vec<PromptMessage>, McpError> {
        Ok(vec![PromptMessage {
            role: PromptMessageRole::User,
            content: PromptMessageContent::text(
                r#"# GitHub Create or Update File Examples

## Create a New File
To create a new file in a repository:

```json
{
  "owner": "octocat",
  "repo": "hello-world",
  "path": "src/new_file.rs",
  "message": "Add new file",
  "content": "fn main() {\n    println!(\"Hello, World!\");\n}"
}
```

## Update an Existing File
To update a file, you MUST provide its current SHA. Get the SHA first using get_file_contents:

```json
{
  "owner": "octocat",
  "repo": "hello-world",
  "path": "README.md",
  "message": "Update README",
  "content": "# Updated README\n\nNew content here...",
  "sha": "abc123def456..."
}
```

## Create File on Specific Branch
To create a file on a non-default branch:

```json
{
  "owner": "octocat",
  "repo": "hello-world",
  "path": "feature.txt",
  "message": "Add feature file",
  "content": "Feature content",
  "branch": "feature-branch"
}
```

## Update File on Branch
To update a file on a specific branch:

```json
{
  "owner": "octocat",
  "repo": "hello-world",
  "path": "config.json",
  "message": "Update config",
  "content": "{\"setting\": \"value\"}",
  "branch": "develop",
  "sha": "def789abc123..."
}
```

## Response Information

The response includes:
- **content**: File information (name, path, sha, size, etc.)
- **commit**: Commit details (sha, author, message, etc.)

## Workflow for Updating Files

1. **Get current file SHA** using get_file_contents:
   ```json
   {"owner": "octocat", "repo": "hello-world", "path": "file.txt"}
   ```

2. **Extract SHA** from response:
   ```json
   {"sha": "abc123..."}
   ```

3. **Update file** with the SHA:
   ```json
   {
     "owner": "octocat",
     "repo": "hello-world",
     "path": "file.txt",
     "message": "Update file",
     "content": "new content",
     "sha": "abc123..."
   }
   ```

## Important Notes

- **Content is plain text** (NOT base64) - the API handles encoding automatically
- **SHA is required for updates** - omitting SHA creates a new file
- **Creates a commit automatically** with the provided message