use std::path::{Path, PathBuf};

use integrity_checker::database::{Database, DiffSummary, Features};

fn check(
    root_dir: impl AsRef<Path>,
    before_features: Features,
    after_features: Features,
) -> DiffSummary {
    let mut before_path = PathBuf::from(root_dir.as_ref());
    before_path.push("before");

    let mut after_path = PathBuf::from(root_dir.as_ref());
    after_path.push("after");

    let threads = 1;
    let before_db = Database::build(&before_path, before_features, threads, false).unwrap();
    before_db
        .check(&after_path, after_features, threads)
        .unwrap()
}

const NONE: Features = Features {
    sha2: false,
    blake2b: false,
};
const SHA2: Features = Features {
    sha2: true,
    blake2b: false,
};
const BLAKE2B: Features = Features {
    sha2: false,
    blake2b: true,
};
const ALL: Features = Features {
    sha2: true,
    blake2b: true,
};

const ALL_FEATURES: &[Features] = &[NONE, SHA2, BLAKE2B, ALL];

// These pairs of features share at least one hash in common (and
// therefore can detect changes even when other metrics don't change).
const VIABLE_FEATURES: &[(Features, Features)] = &[
    (SHA2, ALL),
    (ALL, SHA2),
    (BLAKE2B, ALL),
    (ALL, BLAKE2B),
    (ALL, ALL),
];

// These pairs of features don't share any common hash (and therefore
// can't detect changes except when another metric changes).
const NONVIABLE_FEATURES: &[(Features, Features)] = &[
    (NONE, NONE),
    (NONE, SHA2),
    (SHA2, NONE),
    (NONE, BLAKE2B),
    (BLAKE2B, NONE),
    (SHA2, BLAKE2B),
    (BLAKE2B, SHA2),
];

#[test]
fn no_changes() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check("tests/nochanges", *before_features, *after_features);
            assert_eq!(result, DiffSummary::NoChanges);
        }
    }
}

#[test]
fn changes_edit() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check("tests/changes_edit", *before_features, *after_features);
            assert_eq!(result, DiffSummary::Changes);
        }
    }
}

#[test]
fn changes_edit_no_size_change() {
    for (before_features, after_features) in VIABLE_FEATURES {
        let result = check(
            "tests/changes_edit_no_size_change",
            *before_features,
            *after_features,
        );
        assert_eq!(result, DiffSummary::Changes);
    }
    for (before_features, after_features) in NONVIABLE_FEATURES {
        let result = check(
            "tests/changes_edit_no_size_change",
            *before_features,
            *after_features,
        );
        assert_eq!(result, DiffSummary::NoChanges);
    }
}

#[test]
fn changes_new() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check("tests/changes_new", *before_features, *after_features);
            assert_eq!(result, DiffSummary::Changes);
        }
    }
}

#[test]
fn changes_edit_bin() {
    for (before_features, after_features) in VIABLE_FEATURES {
        let result = check("tests/changes_edit_bin", *before_features, *after_features);
        assert_eq!(result, DiffSummary::Changes);
    }
    for (before_features, after_features) in NONVIABLE_FEATURES {
        let result = check("tests/changes_edit_bin", *before_features, *after_features);
        assert_eq!(result, DiffSummary::NoChanges);
    }
}

#[test]
fn changes_new_bin() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check("tests/changes_new_bin", *before_features, *after_features);
            assert_eq!(result, DiffSummary::Changes);
        }
    }
}

#[test]
fn changes_delete() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check("tests/changes_delete", *before_features, *after_features);
            assert_eq!(result, DiffSummary::Changes);
        }
    }
}

#[test]
fn changes_delete_dir() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check(
                "tests/changes_delete_dir",
                *before_features,
                *after_features,
            );
            assert_eq!(result, DiffSummary::Changes);
        }
    }
}

#[test]
fn suspicious_truncate() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check(
                "tests/suspicious_truncate",
                *before_features,
                *after_features,
            );
            assert_eq!(result, DiffSummary::Suspicious);
        }
    }
}

#[test]
fn suspicious_nul() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check("tests/suspicious_nul", *before_features, *after_features);
            assert_eq!(result, DiffSummary::Suspicious);
        }
    }
}

#[test]
fn suspicious_nonascii() {
    for before_features in ALL_FEATURES {
        for after_features in ALL_FEATURES {
            let result = check(
                "tests/suspicious_nonascii",
                *before_features,
                *after_features,
            );
            assert_eq!(result, DiffSummary::Suspicious);
        }
    }
}