//! Utility functions for working with Debian packages.
use breezyshim::branch::{Branch, GenericBranch};
use breezyshim::debian::apt::Apt;
use breezyshim::tree::{MutableTree, Tree, WorkingTree};
use debian_changelog::{ChangeLog, Urgency};
use debian_control::changes::Changes;
use std::collections::HashMap;

use std::path::Path;

/// Default build command
pub const DEFAULT_BUILDER: &str = "sbuild --no-clean-source";

pub mod codemod;
pub mod run;
pub mod uploader;

/// Check whether the control files are in the root of the package.
pub fn control_files_in_root(tree: &dyn Tree, subpath: &Path) -> bool {
    let debian_path = subpath.join("debian");
    if tree.has_filename(&debian_path) {
        return false;
    }
    let control_path = subpath.join("control");
    if tree.has_filename(&control_path) {
        return true;
    }
    let template_control_path = control_path.with_extension("in");
    tree.has_filename(&template_control_path)
}

#[cfg(not(feature = "detect-update-changelog"))]
#[derive(Debug, Clone, PartialEq, Eq)]
/// Changelog behaviour
pub struct ChangelogBehaviour {
    /// Whether to update the changelog
    pub update_changelog: bool,

    /// Explanation for the decision
    pub explanation: String,
}

#[cfg(feature = "detect-update-changelog")]
pub use debian_analyzer::detect_gbp_dch::ChangelogBehaviour;

/// Guess whether the changelog should be updated.
pub fn guess_update_changelog(
    #[allow(unused_variables)] tree: &dyn WorkingTree,
    #[allow(unused_variables)] debian_path: &Path,
) -> Option<ChangelogBehaviour> {
    #[cfg(feature = "detect-update-changelog")]
    {
        debian_analyzer::detect_gbp_dch::guess_update_changelog(tree, debian_path, None)
    }
    #[cfg(not(feature = "detect-update-changelog"))]
    {
        log::warn!("Install lintian-brush to detect automatically whether the changelog should be updated.");
        return Some(ChangelogBehaviour {
                update_changelog: true,
                explanation: format!(
                    "defaulting to updating changelog since silver-platter was built without lintian-brush"
                ),
            });
    }
}

/// Add a changelog entry.
///
/// # Arguments
/// * `tree` - Tree to edit
/// * `path` - Path to the changelog file
/// * `summary` - Entry to add
/// * `maintainer` - Maintainer details; tuple of fullname and email
pub fn add_changelog_entry(
    tree: &dyn MutableTree,
    path: &Path,
    summary: &[&str],
    maintainer: Option<&(String, String)>,
    timestamp: Option<chrono::DateTime<chrono::FixedOffset>>,
    urgency: Option<Urgency>,
) {
    let maintainer = if let Some(maintainer) = maintainer {
        Some(maintainer.clone())
    } else {
        debian_changelog::get_maintainer()
    };
    // TODO(jelmer): This logic should ideally be in python-debian.
    let f = tree.get_file(path).unwrap();

    let mut cl = ChangeLog::read_relaxed(f).unwrap();

    let summary = vec![format!("* {}", summary[0])]
        .into_iter()
        .chain(summary[1..].iter().map(|l| format!("  {}", l)))
        .collect::<Vec<_>>();

    cl.try_auto_add_change(
        summary
            .iter()
            .map(|l| l.as_str())
            .collect::<Vec<_>>()
            .as_slice(),
        maintainer.unwrap(),
        timestamp,
        urgency,
    )
    .unwrap();
    tree.put_file_bytes_non_atomic(path, cl.to_string().as_bytes())
        .unwrap();
}

/// Check if a directory is a debcargo package.
pub fn is_debcargo_package(tree: &dyn Tree, subpath: &Path) -> bool {
    let control_path = subpath.join("debian").join("debcargo.toml");
    tree.has_filename(&control_path)
}

/// Install the built package.
pub fn install_built_package(
    local_tree: &dyn WorkingTree,
    subpath: &Path,
    build_target_dir: &Path,
) -> Result<(), Box<dyn std::error::Error>> {
    let abspath = local_tree
        .abspath(subpath)
        .unwrap()
        .join("debian/changelog");

    let cl = ChangeLog::read_path(abspath)?;

    let first_entry = cl.iter().next().unwrap();

    let package = first_entry.package().unwrap();
    let version = first_entry.version().unwrap();

    let mut non_epoch_version = version.upstream_version.clone();
    if let Some(debian_version) = &version.debian_revision {
        non_epoch_version.push_str(&format!("-{}", debian_version));
    }

    let re_pattern = format!(
        "{}_{}_.*\\.changes",
        regex::escape(&package),
        regex::escape(&non_epoch_version)
    );
    let c = regex::Regex::new(&re_pattern)?;

    for entry in std::fs::read_dir(build_target_dir)? {
        let entry = entry?;
        let file_name = entry.file_name().into_string().unwrap_or_default();
        if !c.is_match(&file_name) {
            continue;
        }

        let path = entry.path();
        let contents = std::fs::read_to_string(&path)?;

        let parse_result = Changes::parse(&contents);
        if !parse_result.errors().is_empty() {
            return Err(Box::new(std::io::Error::new(
                std::io::ErrorKind::InvalidData,
                format!("Failed to parse changes file: {:?}", parse_result.errors()),
            )));
        }
        let changes = parse_result.tree();

        let binary = changes.binary();

        if binary.is_some() {
            std::process::Command::new("debi")
                .arg(entry.path())
                .status()?;
        }
    }

    Ok(())
}

/// Build a debian package in a directory.
///
/// # Arguments
/// * `tree` - Working tree
/// * `subpath` - Subpath to build in
/// * `branch` - Branch
/// * `builder` - Builder command (e.g. 'sbuild', 'debuild')
/// * `result_dir` - Directory to copy results to
pub fn build(
    tree: &breezyshim::workingtree::GenericWorkingTree,
    subpath: &Path,
    branch: &breezyshim::branch::GenericBranch,
    builder: Option<&str>,
    result_dir: Option<&Path>,
) -> Result<std::collections::HashMap<String, std::path::PathBuf>, breezyshim::debian::error::Error>
{
    let builder = builder.unwrap_or(DEFAULT_BUILDER);
    let result_dir = result_dir.unwrap_or_else(|| Path::new(".."));

    breezyshim::debian::build_helper(
        tree, subpath, branch, result_dir, builder, false, // guess_upstream_branch_url
        None,  // apt_repo
    )
}

/// Run `gbp dch` in a directory.
pub fn gbp_dch(path: &std::path::Path) -> Result<(), std::io::Error> {
    let mut cmd = std::process::Command::new("gbp");
    cmd.arg("dch").arg("--ignore-branch");
    cmd.current_dir(path);
    let status = cmd.status()?;
    if !status.success() {
        return Err(std::io::Error::other(format!("gbp dch failed: {}", status)));
    }
    Ok(())
}

/// Find the last release revision id for a given version.
pub fn find_last_release_revid(
    branch: &GenericBranch,
    version: debversion::Version,
) -> Result<breezyshim::revisionid::RevisionId, breezyshim::debian::error::Error> {
    let db = breezyshim::debian::import_dsc::DistributionBranch::new(branch, branch, None, None);
    db.revid_of_version(&version)
}

/// Pick the additional colocated branches to use for a given main branch.
pub fn pick_additional_colocated_branches(main_branch: &GenericBranch) -> HashMap<String, String> {
    let mut ret: HashMap<String, String> = vec![
        ("pristine-tar", "pristine-tar"),
        ("pristine-lfs", "pristine-lfs"),
        ("upstream", "upstream"),
    ]
    .into_iter()
    .map(|(k, v)| (k.to_string(), v.to_string()))
    .collect();

    if let Some(name) = main_branch.name() {
        ret.insert(format!("patch-queue/{}", name), "patch-queue".to_string());

        if name.starts_with("debian/") {
            let mut parts = name.split('/').collect::<Vec<_>>();
            parts[0] = "upstream";
            ret.insert(parts.join("/"), "upstream".to_string());
        }
    }
    let existing_branch_names = main_branch.controldir().branch_names().unwrap();

    ret.into_iter()
        .filter(|(k, _)| existing_branch_names.contains(k))
        .collect()
}

/// Get source package metadata.
///
/// # Arguments
/// * `apt_repo` - A `Apt` object
/// * `name` - Name of the source package
pub fn apt_get_source_package(
    apt_repo: &dyn Apt,
    name: &str,
) -> Option<debian_control::apt::Source> {
    let mut by_version = HashMap::new();

    for source in apt_repo.iter_source_by_name(name) {
        by_version.insert(source.version().unwrap(), source);
    }

    if by_version.is_empty() {
        return None;
    }

    // Try the latest version
    let latest_version = by_version.keys().max().unwrap().clone();

    by_version.remove(&latest_version)
}

/// Open a packaging branch from a location string.
///
/// location can either be a package name or a full URL
pub fn open_packaging_branch(
    location: &str,
    possible_transports: Option<&mut Vec<breezyshim::transport::Transport>>,
    vcs_type: Option<&str>,
    apt_repo: Option<&dyn Apt>,
) -> Result<(GenericBranch, std::path::PathBuf), crate::vcs::BranchOpenError> {
    let mut vcs_type = vcs_type.map(|s| s.to_string());
    let (url, branch_name, subpath) = if !location.contains('/') && !location.contains(':') {
        let pkg_source = if apt_repo.is_none() {
            apt_get_source_package(
                &breezyshim::debian::apt::LocalApt::new(None).unwrap(),
                location,
            )
        } else {
            apt_get_source_package(apt_repo.unwrap(), location)
        };

        let pkg_source = match pkg_source {
            Some(pkg_source) => pkg_source,
            None => {
                return Err(crate::vcs::BranchOpenError::Missing {
                    url: location.parse().unwrap(),
                    description: format!("Package {} not found in apt", location),
                })
            }
        };

        match debian_analyzer::vcs::vcs_field(&pkg_source) {
            Some((new_vcs_type, vcs_url)) => {
                vcs_type = Some(new_vcs_type);
                let parsed_vcs: debian_control::vcs::ParsedVcs = vcs_url.parse().unwrap();
                (
                    parsed_vcs.repo_url.parse().unwrap(),
                    parsed_vcs.branch,
                    Some(std::path::PathBuf::from("")),
                )
            }
            None => {
                return Err(crate::vcs::BranchOpenError::Missing {
                    url: location.parse().unwrap(),
                    description: format!("Package {} does not have VCS information", location),
                })
            }
        }
    } else {
        let (url, params) =
            breezyshim::urlutils::split_segment_parameters(&location.parse().unwrap());
        let branch_name = params.get("branch").map(|b| {
            percent_encoding::percent_decode_str(b)
                .decode_utf8()
                .unwrap()
                .into_owned()
        });
        (url, branch_name, None)
    };
    let probers = crate::probers::select_probers(vcs_type.as_deref());
    let branch = crate::vcs::open_branch(
        &url,
        possible_transports,
        Some(
            probers
                .iter()
                .map(|p| p.as_ref())
                .collect::<Vec<_>>()
                .as_slice(),
        ),
        branch_name.as_deref(),
    )?;
    Ok((
        branch,
        subpath.unwrap_or_else(|| std::path::PathBuf::from("")),
    ))
}

#[cfg(test)]
mod tests {
    use super::*;
    use breezyshim::controldir::{create_branch_convenience_as_generic, ControlDirFormat};
    use std::path::Path;

    pub fn make_branch_and_tree(
        path: &std::path::Path,
    ) -> breezyshim::workingtree::GenericWorkingTree {
        breezyshim::init();
        let path = path.canonicalize().unwrap();
        let url = url::Url::from_file_path(path).unwrap();
        let branch =
            create_branch_convenience_as_generic(&url, None, &ControlDirFormat::default()).unwrap();
        branch.controldir().open_workingtree().unwrap()
    }

    #[test]
    fn test_edit_existing_new_author() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  * Initial change.
  * Support updating templated debian/control files that use cdbs
    template.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#
            .as_bytes(),
        )
        .unwrap();
        tree.add(&[(Path::new("debian")), (Path::new("debian/changelog"))])
            .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &["Add a foo"],
            Some(&("Jane Example".to_string(), "jane@example.com".to_string())),
            None,
            None,
        );
        assert_eq!(
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  [ Joe Example ]
  * Initial change.
  * Support updating templated debian/control files that use cdbs
    template.

  [ Jane Example ]
  * Add a foo

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap(),
        );
    }

    #[test]
    fn test_edit_existing_multi_new_author() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  [ Jane Example ]
  * Support updating templated debian/control files that use cdbs
    template.

  [ Joe Example ]
  * Another change

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
        )
        .unwrap();
        tree.add(&[(Path::new("debian")), (Path::new("debian/changelog"))])
            .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &["Add a foo"],
            Some(&("Jane Example".to_string(), "jane@example.com".to_string())),
            None,
            None,
        );
        assert_eq!(
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  [ Jane Example ]
  * Support updating templated debian/control files that use cdbs
    template.

  [ Joe Example ]
  * Another change

  [ Jane Example ]
  * Add a foo

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap()
        );
    }

    #[test]
    fn test_edit_existing_existing_author() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
        )
        .unwrap();
        tree.add(&[(Path::new("debian")), (Path::new("debian/changelog"))])
            .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &["Add a foo"],
            Some(&("Joe Example".to_string(), "joe@example.com".to_string())),
            None,
            None,
        );
        assert_eq!(
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.
  * Add a foo

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap()
        );
    }

    #[test]
    fn test_add_new() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"lintian-brush (0.35) unstable; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
        )
        .unwrap();
        tree.add(&[(Path::new("debian")), (Path::new("debian/changelog"))])
            .unwrap();
        std::env::set_var("DEBCHANGE_VENDOR", "debian");
        let timestamp = chrono::DateTime::<chrono::FixedOffset>::parse_from_rfc3339(
            "2020-05-24T15:27:26+00:00",
        )
        .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &["Add a foo"],
            Some(&(
                String::from("Jane Example"),
                String::from("jane@example.com"),
            )),
            Some(timestamp),
            None,
        );
        assert_eq!(
            r#"lintian-brush (0.36) UNRELEASED; urgency=low

  * Add a foo

 -- Jane Example <jane@example.com>  Sun, 24 May 2020 15:27:26 +0000

lintian-brush (0.35) unstable; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap()
        );
    }

    #[test]
    fn test_edit_broken_first_line() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"THIS IS NOT A PARSEABLE LINE
lintian-brush (0.35) UNRELEASED; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
        )
        .unwrap();
        tree.add(&[Path::new("debian"), Path::new("debian/changelog")])
            .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &["Add a foo", "+ Bar"],
            Some(&("Jane Example".to_string(), "joe@example.com".to_string())),
            None,
            None,
        );
        assert_eq!(
            r#"THIS IS NOT A PARSEABLE LINE
lintian-brush (0.35) UNRELEASED; urgency=medium

  [ Joe Example ]
  * Support updating templated debian/control files that use cdbs
    template.

  [ Jane Example ]
  * Add a foo
    + Bar

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap()
        );
    }

    #[test]
    fn test_add_long_line() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#
            .as_bytes(),
        )
        .unwrap();
        tree.add(&[Path::new("debian"), Path::new("debian/changelog")])
            .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &[
                "This is adding a very long sentence that is longer than would fit on a single line in a 80-character-wide line."
            ],
            Some(&("Joe Example".to_string(), "joe@example.com".to_string())),
            None,
            None,
        );
        assert_eq!(
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.
  * This is adding a very long sentence that is longer than would fit on a
    single line in a 80-character-wide line.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap()
        );
    }

    #[test]
    fn test_add_long_subline() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#
            .as_bytes(),
        )
        .unwrap();
        tree.add(&[Path::new("debian"), Path::new("debian/changelog")])
            .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &[
                "This is the main item.",
                "+ This is adding a very long sentence that is longer than would fit on a single line in a 80-character-wide line.",
            ],
            Some(&("Joe Example".to_string(), "joe@example.com".to_string())), None, None
        );
        assert_eq!(
            r#"lintian-brush (0.35) UNRELEASED; urgency=medium

  * Support updating templated debian/control files that use cdbs
    template.
  * This is the main item.
    + This is adding a very long sentence that is longer than would fit on a
      single line in a 80-character-wide line.

 -- Joe Example <joe@example.com>  Fri, 04 Oct 2019 02:36:13 +0000
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap()
        );
    }

    #[test]
    fn test_trailer_only() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"lintian-brush (0.35) unstable; urgency=medium

  * This line already existed.

 -- 
"#
            .as_bytes(),
        )
        .unwrap();
        tree.add(&[Path::new("debian"), Path::new("debian/changelog")])
            .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &["And this one is new."],
            Some(&("Jane Example".to_string(), "joe@example.com".to_string())),
            None,
            None,
        );
        assert_eq!(
            r#"lintian-brush (0.35) unstable; urgency=medium

  * This line already existed.
  * And this one is new.

 -- 
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap()
        );
    }

    #[test]
    fn test_trailer_only_existing_author() {
        let td = tempfile::tempdir().unwrap();
        let tree = make_branch_and_tree(td.path());
        std::fs::create_dir_all(td.path().join("debian")).unwrap();
        std::fs::write(
            td.path().join("debian/changelog"),
            r#"lintian-brush (0.35) unstable; urgency=medium

  * This line already existed.

  [ Jane Example ]
  * And this one has an existing author.

 -- 
"#
            .as_bytes(),
        )
        .unwrap();
        tree.add(&[Path::new("debian"), Path::new("debian/changelog")])
            .unwrap();
        add_changelog_entry(
            &tree,
            Path::new("debian/changelog"),
            &["And this one is new."],
            Some(&("Joe Example".to_string(), "joe@example.com".to_string())),
            None,
            None,
        );
        assert_eq!(
            r#"lintian-brush (0.35) unstable; urgency=medium

  * This line already existed.

  [ Jane Example ]
  * And this one has an existing author.

  [ Joe Example ]
  * And this one is new.

 -- 
"#,
            std::fs::read_to_string(td.path().join("debian/changelog")).unwrap()
        );
    }
}
