// Copyright 2020 Nym Technologies SA
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

use semver::SemVerError;
pub use semver::Version;

/// Checks whether given `version` is compatible with a given semantic version requirement `req`
/// according to major-minor semver rules. The semantic version requirement can be passed as a full,
/// concrete version number, because that's what we'll have in our Cargo.toml files (e.g. 0.3.2).
/// The patch number in the requirement gets dropped and replaced with a wildcard (0.3.*) as all
/// minor versions should be compatible with each other.
pub fn is_minor_version_compatible(version: &str, req: &str) -> bool {
    let expected_version = match Version::parse(version) {
        Ok(v) => v,
        Err(_) => return false,
    };
    let req_version = match Version::parse(req) {
        Ok(v) => v,
        Err(_) => return false,
    };

    expected_version.major == req_version.major && expected_version.minor == req_version.minor
}

pub fn parse_version(raw_version: &str) -> Result<Version, SemVerError> {
    Version::parse(raw_version)
}

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

    #[test]
    fn version_0_3_0_is_compatible_with_requirement_0_3_x() {
        assert!(is_minor_version_compatible("0.3.0", "0.3.2"));
    }

    #[test]
    fn version_0_3_1_is_compatible_with_minimum_requirement_0_3_x() {
        assert!(is_minor_version_compatible("0.3.1", "0.3.2"));
    }

    #[test]
    fn version_0_3_2_is_compatible_with_minimum_requirement_0_3_x() {
        assert!(is_minor_version_compatible("0.3.2", "0.3.0"));
    }

    #[test]
    fn version_0_2_0_is_not_compatible_with_requirement_0_3_x() {
        assert!(!is_minor_version_compatible("0.2.0", "0.3.2"));
    }

    #[test]
    fn version_0_4_0_is_not_compatible_with_requirement_0_3_x() {
        assert!(!is_minor_version_compatible("0.4.0", "0.3.2"));
    }

    #[test]
    fn version_1_3_2_is_not_compatible_with_requirement_0_3_x() {
        assert!(!is_minor_version_compatible("1.3.2", "0.3.2"));
    }

    #[test]
    fn version_0_4_0_rc_1_is_compatible_with_version_0_4_0_rc_1() {
        assert!(is_minor_version_compatible("0.4.0-rc.1", "0.4.0-rc.1"));
    }

    #[test]
    fn returns_false_on_foo_version() {
        assert!(!is_minor_version_compatible("foo", "0.3.2"));
    }

    #[test]
    fn returns_false_on_bar_version() {
        assert!(!is_minor_version_compatible("0.3.2", "bar"));
    }
}