//! Git's text summaries for small, textual diffs.
use crate::changes::{FileDiff, Kind, Status};
use gix::bstr::ByteSlice;
pub(crate) fn commit(commit: &gix::Commit<'_>) -> crate::Result<()> {
    let decoded = commit
        .decode()
        .map_err(|e| crate::repo::error("commit output", e))?;
    println!("commit {}", commit.id);
    if decoded.parents.len() > 1 {
        println!(
            "Merge: {}",
            decoded
                .parents
                .iter()
                .map(|id| id.to_string()[..7].to_owned())
                .collect::<Vec<_>>()
                .join(" ")
        );
    }
    let author = commit
        .author()
        .map_err(|e| crate::repo::error("commit author", e))?;
    let time = author
        .time()
        .map_err(|e| crate::repo::error("commit date", e))?;
    println!(
        "Author: {} <{}>\nDate:   {}\n\n    {}",
        author.name,
        author.email,
        time.format_or_unix(gix::date::time::format::DEFAULT),
        decoded
            .message
            .to_str_lossy()
            .trim_end()
            .replace('\n', "\n    ")
    );
    Ok(())
}
pub(crate) fn author_date(commit: &gix::Commit<'_>) -> crate::Result<()> {
    let author = commit
        .author()
        .map_err(|e| crate::repo::error("author", e))?;
    println!(
        " Date: {}",
        author
            .time()
            .map_err(|e| crate::repo::error("date", e))?
            .format_or_unix(gix::date::time::format::DEFAULT)
    );
    Ok(())
}
pub(crate) fn long_status(s: &Status) {
    let branch = s
        .head
        .branch
        .as_deref()
        .unwrap_or("HEAD")
        .trim_start_matches("refs/heads/");
    if s.head.detached {
        println!(
            "HEAD detached at {}",
            &s.head.id.as_deref().unwrap_or("HEAD")[..7]
        );
    } else {
        println!("On branch {branch}");
    }
    if s.head.unborn {
        println!("\nNo commits yet\n");
    }
    if !s.staged.is_empty() {
        println!("Changes to be committed:");
        println!(
            "  (use \"git {} <file>...\" to unstage)",
            if s.head.unborn {
                "rm --cached"
            } else {
                "restore --staged"
            }
        );
        for c in &s.staged {
            println!("\t{:12}{}", label(&c.status), c.path);
        }
        println!();
    }
    if !s.unstaged.is_empty() {
        println!("Changes not staged for commit:");
        println!("  (use \"git add <file>...\" to update what will be committed)");
        println!("  (use \"git restore <file>...\" to discard changes in working directory)");
        for c in &s.unstaged {
            println!("\t{:12}{}", label(&c.status), c.path);
        }
        println!();
    }
    if !s.untracked.is_empty() {
        println!(
            "Untracked files:\n  (use \"git add <file>...\" to include in what will be committed)"
        );
        for path in &s.untracked {
            println!("\t{path}");
        }
        println!();
    }
    if s.staged.is_empty() {
        if !s.unstaged.is_empty() {
            println!("no changes added to commit (use \"git add\" and/or \"git commit -a\")");
        } else if !s.untracked.is_empty() {
            println!(
                "nothing added to commit but untracked files present (use \"git add\" to track)"
            );
        } else if s.head.unborn {
            println!("nothing to commit (create/copy files and use \"git add\" to track)");
        } else {
            println!("nothing to commit, working tree clean");
        }
    }
}
fn label(kind: &Kind) -> &'static str {
    match kind {
        Kind::Added => "new file:",
        Kind::Modified => "modified:",
        Kind::Deleted => "deleted:",
        Kind::Renamed => "renamed:",
    }
}
pub(crate) fn numstat(diff: &FileDiff, nul: bool) {
    let hunks = diff.patch.lines().skip_while(|l| !l.starts_with("@@"));
    let added = hunks.clone().filter(|l| l.starts_with('+')).count();
    let removed = hunks.filter(|l| l.starts_with('-')).count();
    let (added, removed) = if diff.binary {
        ("-".into(), "-".into())
    } else {
        (added.to_string(), removed.to_string())
    };
    print!(
        "{added}\t{removed}\t{}{}",
        diff.path,
        if nul { "\0" } else { "\n" }
    );
}
pub(crate) fn stat(diffs: &[FileDiff], summary: bool) {
    summarize(diffs, true, summary);
}
pub(crate) fn commit_stat(diffs: &[FileDiff]) {
    summarize(diffs, false, true);
}
fn summarize(diffs: &[FileDiff], names: bool, summary: bool) {
    let width = diffs.iter().map(|d| d.path.len()).max().unwrap_or(0);
    let mut insertions = 0;
    let mut deletions = 0;
    for diff in diffs {
        let added = diff
            .patch
            .lines()
            .filter(|l| l.starts_with('+') && !l.starts_with("+++"))
            .count();
        let removed = diff
            .patch
            .lines()
            .filter(|l| l.starts_with('-') && !l.starts_with("---"))
            .count();
        insertions += added;
        deletions += removed;
        if names {
            println!(
                " {:width$} | {} {}{}",
                diff.path,
                added + removed,
                "+".repeat(added),
                "-".repeat(removed)
            );
        }
    }
    if diffs.is_empty() {
        return;
    }
    print!(
        " {} file{} changed",
        diffs.len(),
        if diffs.len() == 1 { "" } else { "s" }
    );
    if insertions > 0 {
        print!(
            ", {insertions} insertion{}(+)",
            if insertions == 1 { "" } else { "s" }
        );
    }
    if deletions > 0 {
        print!(
            ", {deletions} deletion{}(-)",
            if deletions == 1 { "" } else { "s" }
        );
    }
    println!();
    if summary {
        for d in diffs {
            match d.status {
                Kind::Added => println!(" create mode 100644 {}", d.path),
                Kind::Deleted => println!(" delete mode 100644 {}", d.path),
                _ => (),
            }
        }
    }
}
pub(crate) fn conflicts(paths: &[String], merge: bool) {
    for path in paths {
        println!("Auto-merging {path}");
        println!("CONFLICT (content): Merge conflict in {path}");
    }
    if merge && !paths.is_empty() {
        println!("Automatic merge failed; fix conflicts and then commit the result.");
    }
}