use std::path::Path;

pub struct ShellScript {
    lines: Vec<String>,
}

impl ShellScript {
    pub fn new() -> Self {
        Self {
            lines: Vec::new(),
        }
    }

    pub fn add_comment(&mut self, comment: &str) {
        self.lines.push(format!("# {}", comment));
    }

    pub fn add_variable(&mut self, name: &str, value: &Path) {
        let escaped = escape_path(value);
        self.lines.push(format!("{}=\"{}\"", name, escaped));
    }

    pub fn add_variable_str(&mut self, name: &str, value: &str) {
        let escaped = value.replace('"', r#"\""#).replace('$', r#"\$"#);
        self.lines.push(format!("{}=\"{}\"", name, escaped));
    }

    pub fn add_command(&mut self, command: &str) {
        self.lines.push(command.to_string());
    }

    pub fn add_empty_line(&mut self) {
        self.lines.push(String::new());
    }

    pub fn output(&self) -> String {
        self.lines.join("\n")
    }
}

fn escape_path(path: &Path) -> String {
    path.display().to_string().replace('"', r#"\""#).replace('$', r#"\$"#)
}

pub fn print_shell_script_header() {
    println!("#!/bin/sh");
    println!("# Generated by bilibili-merge dry-run mode");
    println!();
}

pub fn print_shell_script(script: &ShellScript) {
    println!("{}", script.output());
}