use crate::template::{Context, find, parse};
use std::fs::write;
use std::io::{Error, Result};
use std::path::Path;

const FILENAME: &str = "index.gph";

pub fn archive(
    _: &Path,
    template_directory: &Path,
    target: &Path,
    context: &Context,
) -> Result<()> {
    if let Some(template) = find(template_directory, FILENAME) {
        let parsed_template = parse(&template)
            .ok_or_else(|| Error::other("Unable to parse Gopher Archive template"))?;
        let rendered_template = parsed_template.render(context)?;
        let location = target.join(FILENAME);
        write(location, rendered_template)?;
    }
    Ok(())
}

#[cfg(test)]
mod tests {
    use std::collections::HashMap;
    use std::fs::create_dir_all;

    use super::*;
    use crate::template::Value;

    use test_utilities::*;

    #[test]
    fn test_renders_the_context_into_the_template() {
        let test_dir = setup_test_dir();
        let template_dir = test_dir.join("template");
        let output_dir = test_dir.join("output");
        create_dir_all(&output_dir).expect("Could not create output test directory");
        create_dir_all(&template_dir).expect("Could not create template test directory");

        create_test_file(&template_dir.join("index.gph"), "Simple {{= test }}");

        let context: Context =
            HashMap::from([("test".to_string(), Value::String("things".to_string()))]);

        archive(&test_dir, &template_dir, &output_dir, &context).expect("Archive failed");

        assert_file_contents(&output_dir.join("index.gph"), "Simple things");
        cleanup_test_dir(&test_dir);
    }

    #[test]
    fn test_fails_if_template_is_malformed() {
        let test_dir = setup_test_dir();
        let template_dir = test_dir.join("template");
        let output_dir = test_dir.join("output");
        create_dir_all(&output_dir).expect("Could not create output test directory");
        create_dir_all(&template_dir).expect("Could not create template test directory");

        create_test_file(&template_dir.join("index.gph"), "Simple {{ test }}");

        let context: Context =
            HashMap::from([("test".to_string(), Value::String("things".to_string()))]);

        let result = archive(&test_dir, &template_dir, &output_dir, &context);

        assert!(result.is_err());
        cleanup_test_dir(&test_dir);
    }

    #[test]
    fn test_fails_if_output_folder_is_not_writable() {
        let test_dir = setup_test_dir();
        let template_dir = test_dir.join("template");
        let output_dir = test_dir.join("gopherunwritable/folder/please");
        create_dir_all(&template_dir).expect("Could not create template test directory");

        create_test_file(&template_dir.join("index.gph"), "Simple {{= test }}");

        let context: Context =
            HashMap::from([("test".to_string(), Value::String("things".to_string()))]);

        let result = archive(&test_dir, &template_dir, &output_dir, &context);

        assert!(result.is_err());
        cleanup_test_dir(&test_dir);
    }
}