use std::io::prelude::*;
use std::fs::{File, create_dir};
use std::path::Path;

use errors::{Result, ResultExt};

pub fn create_file<P: AsRef<Path>>(path: P, content: &str) -> Result<()> {
    let mut file = File::create(&path)?;
    file.write_all(content.as_bytes())?;
    Ok(())
}

/// Very similar to `create_dir` from the std except it checks if the folder
/// exists before creating it
pub fn create_directory<P: AsRef<Path>>(path: P) -> Result<()> {
    let path = path.as_ref();
    if !path.exists() {
        create_dir(path)
            .chain_err(|| format!("Was not able to create folder {}", path.display()))?;
    }
    Ok(())
}


/// Return the content of a file, with error handling added
pub fn read_file<P: AsRef<Path>>(path: P) -> Result<String> {
    let path = path.as_ref();

    let mut content = String::new();
    File::open(path)
        .chain_err(|| format!("Failed to open '{:?}'", path.display()))?
        .read_to_string(&mut content)?;

    Ok(content)
}


/// Takes a full path to a .md and returns only the components after the `content` directory
/// Will not return the filename as last component
pub fn find_content_components<P: AsRef<Path>>(path: P) -> Vec<String> {
    let path = path.as_ref();
    let mut is_in_content = false;
    let mut components = vec![];

    for section in path.parent().unwrap().components() {
        let component = section.as_ref().to_string_lossy();

        if is_in_content {
            components.push(component.to_string());
            continue;
        }

        if component == "content" {
            is_in_content = true;
        }
    }

    components
}

#[cfg(test)]
mod tests {
    use super::{find_content_components};

    #[test]
    fn test_find_content_components() {
        let res = find_content_components("/home/vincent/code/site/content/posts/tutorials/python.md");
        assert_eq!(res, ["posts".to_string(), "tutorials".to_string()]);
    }
}