use std::fs;
use std::io::Write;
use std::path::Path;
use std::process::Command;

use chrono::Local;

use crate::config::Settings;
use crate::error::StreamdError;
use crate::extract::parse_markdown_file;

pub fn run() -> Result<(), StreamdError> {
    let settings = Settings::load()?;
    let streamd_directory = &settings.base_folder;

    let timestamp = Local::now().format("%Y%m%d-%H%M%S").to_string();
    let preliminary_file_name = format!("{}_wip.md", timestamp);
    let preliminary_path = Path::new(streamd_directory).join(&preliminary_file_name);

    // Create initial file with heading
    let content = "# ";
    let mut file = fs::File::create(&preliminary_path)?;
    file.write_all(content.as_bytes())?;
    drop(file);

    // Open in editor
    let editor = std::env::var("EDITOR").unwrap_or_else(|_| "vi".to_string());
    let status = Command::new(&editor).arg(&preliminary_path).status()?;

    if !status.success() {
        return Err(StreamdError::IoError(std::io::Error::other(
            "Editor exited with non-zero status",
        )));
    }

    // Read the edited content
    let edited_content = fs::read_to_string(&preliminary_path)?;
    let parsed_content =
        parse_markdown_file(preliminary_path.to_string_lossy().as_ref(), &edited_content);

    // Determine final filename based on markers
    let final_file_name = if let Some(ref shard) = parsed_content.shard {
        if !shard.markers.is_empty() {
            format!("{} {}.md", timestamp, shard.markers.join(" "))
        } else {
            format!("{}.md", timestamp)
        }
    } else {
        format!("{}.md", timestamp)
    };

    let final_path = Path::new(streamd_directory).join(&final_file_name);

    // Rename the file
    fs::rename(&preliminary_path, &final_path)?;

    println!("Saved as {}", final_file_name);

    Ok(())
}