use iggy::error::IggyError;
use std::fmt::Display;
use std::str::FromStr;

const VERSION: &str = env!("CARGO_PKG_VERSION");

#[derive(Debug)]
pub struct SemanticVersion {
    pub major: u32,
    pub minor: u32,
    pub patch: u32,
}

impl FromStr for SemanticVersion {
    type Err = IggyError;
    fn from_str(s: &str) -> Result<Self, Self::Err> {
        let mut version = s.split('.');
        let major = version.next().unwrap().parse::<u32>()?;
        let minor = version.next().unwrap().parse::<u32>()?;
        let patch = version.next().unwrap().parse::<u32>()?;
        Ok(SemanticVersion {
            major,
            minor,
            patch,
        })
    }
}

impl SemanticVersion {
    pub fn current() -> Result<Self, IggyError> {
        if let Ok(version) = VERSION.parse::<SemanticVersion>() {
            return Ok(version);
        }

        Err(IggyError::InvalidVersion(VERSION.into()))
    }

    pub fn is_equal_to(&self, other: &SemanticVersion) -> bool {
        self.major == other.major && self.minor == other.minor && self.patch == other.patch
    }

    pub fn is_greater_than(&self, other: &SemanticVersion) -> bool {
        if self.major > other.major {
            return true;
        }
        if self.major < other.major {
            return false;
        }

        if self.minor > other.minor {
            return true;
        }
        if self.minor < other.minor {
            return false;
        }

        if self.patch > other.patch {
            return true;
        }
        if self.patch < other.patch {
            return false;
        }

        false
    }

    pub fn get_numeric_version(&self) -> Result<u32, IggyError> {
        let major = self.major;
        let minor = format!("{:03}", self.minor);
        let patch = format!("{:03}", self.patch);
        if let Ok(version) = format!("{major}{minor}{patch}").parse::<u32>() {
            return Ok(version);
        }

        Err(IggyError::InvalidVersion(self.to_string()))
    }
}

impl Display for SemanticVersion {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(
            f,
            "{major}.{minor}.{patch}",
            major = self.major,
            minor = self.minor,
            patch = self.patch
        )
    }
}

mod tests {
    #[test]
    fn should_load_the_expected_version_from_package_definition() {
        use super::VERSION;

        const CARGO_TOML_VERSION: &str = env!("CARGO_PKG_VERSION");
        assert_eq!(VERSION, CARGO_TOML_VERSION);
    }
}