use crate::result::Result;
use anyhow::{anyhow, Context};
use std::{env::var, net::SocketAddr, path::PathBuf};

#[derive(Debug, Clone)]
pub struct Config {
    pub bind_addr: SocketAddr,
    pub db_path: PathBuf,
    pub img_path: PathBuf,
}

impl Config {
    pub fn from_env() -> Result<Self> {
        let config = Self {
            bind_addr: var("GL_BIND_ADDR")
                .with_context(|| "Bind address missing.")?
                .parse()
                .with_context(|| "Failed to parse bind address.")?,
            db_path: var("GL_DB_PATH")
                .with_context(|| "Database path missing.")?
                .parse()
                .with_context(|| "Failed to parse database path.")?,
            img_path: var("GL_IMG_PATH")
                .with_context(|| "Image store path missing.")?
                .parse()
                .with_context(|| "Failed to parse image store path.")?,
        };

        if config.db_path.is_dir() {
            Err(anyhow!(format!(
                "Database path {:?} is not a regular file",
                config.db_path
            )))
        } else if !config.img_path.is_dir() {
            Err(anyhow!(format!(
                "Image store path {:?} is not a directory.",
                config.img_path
            )))
        } else if config.img_path.read_dir().is_err() {
            Err(anyhow!(format!(
                "Image store path {:?} is not readable.",
                config.img_path
            )))
        } else {
            Ok(config)
        }
    }
}