use semver::Version;
use serde::{Deserialize, Serialize};

use crate::package::PackageHandler;

/// Data struct
#[derive(Debug, Clone, Deserialize, Serialize, Hash, PartialEq, Eq, PartialOrd, Ord)]
pub struct Dependency {
    name: String,
    #[serde(skip_serializing_if = "<Option<_>>::is_none")]
    version: Option<Version>,
    pub checksum: String,
    #[serde(skip_serializing_if = "<Option<_>>::is_none")]
    source: Option<String>, // Path / URL
}

impl Dependency {
    /// Returns a path to the dependency in local storage
    /// if there is one.
    pub fn local_path(&self) -> String {
        if self.source.as_ref().is_some_and(|path| !is_url(path)) {
            return self.source.clone().unwrap();
        }

        // TODO: Convert from reverse domain name to path.
        return self.name.clone();
    }

    pub fn is_updated(&self) -> crate::Result<bool> {
        // If the path is local and that file has not been updated.
        Ok(self.source.as_ref().is_some_and(|path| is_url(path))
            && self.checksum == sha256::try_digest(self.source.as_ref().unwrap())?)
    }
}

impl From<PackageHandler> for Dependency {
    fn from(value: PackageHandler) -> Self {
        Dependency {
            name: value.name(),
            version: Some(value.version()),
            checksum: String::new(),
            source: None,
        }
    }
}

/// TODO: This is just a placeholder at present.
fn is_url<S: ToString>(_path: S) -> bool {
    return false;
}