use std::env;
use std::io::Write;

extern crate clap;
use clap::{Command, arg, command};
use pkh::context::ContextConfig;

extern crate flate2;

use pkh::changelog::generate_entry;

use indicatif_log_bridge::LogWrapper;
use log::{error, info};

/// Obtain the current working directory, exiting with a helpful message on failure.
fn current_dir_or_exit() -> std::path::PathBuf {
    match std::env::current_dir() {
        Ok(p) => p,
        Err(e) => {
            error!("Could not determine the current working directory: {}", e);
            std::process::exit(1);
        }
    }
}

fn main() {
    let rt = tokio::runtime::Runtime::new().unwrap();
    let logger =
        env_logger::Builder::from_env(env_logger::Env::default().default_filter_or("info"))
            .format_timestamp(None)
            .format(|buf, record| writeln!(buf, "{}", record.args()))
            .build();
    let multi = indicatif::MultiProgress::new();
    LogWrapper::new(multi.clone(), logger).try_init().unwrap();
    let matches = command!()
        .subcommand_required(true)
        .disable_version_flag(true)
        .subcommand(
            Command::new("pull")
                .about("Pull a source package from the archive or git")
                .arg(
                    arg!(-s --series <series> "Target package distribution series").required(false),
                )
                .arg(
                    arg!(-d --dist <dist> "Target package distribution (debian, ubuntu)")
                        .required(false),
                )
                .arg(arg!(-v --version <version> "Target package version").required(false))
                .arg(arg!(--archive "Only use the archive to download package source, not git").required(false))
                .arg(arg!(--ppa <ppa> "Download the package from a specific PPA").required(false))
                .arg(arg!(-p --pocket <pocket> "Target package distribution pocket (updates, security, proposed)").required(false))
                .arg(arg!(<package> "Target package")),
        )
        .subcommand(
            Command::new("chlog")
                .about("Auto-generate changelog entry, editing it, committing it afterwards")
                .arg(arg!(-s --series <series> "Target distribution series").required(false))
                .arg(arg!(--backport "This changelog is for a backport entry").required(false))
                .arg(arg!(-v --version <version> "Target version").required(false)),
        )
        .subcommand(Command::new("build").about("Build the source package (into a .dsc)"))
        .subcommand(
            Command::new("deb")
                .about("Build the source package into binary package (.deb)")
                .arg(arg!(-s --series <series> "Target distribution series").required(false))
                .arg(arg!(-a --arch <arch> "Target architecture").required(false))
                .arg(arg!(-p --pocket <pocket> "Build against dependencies from a specific distribution pocket (updates, security, proposed)").required(false)
                    .long_help("Build against dependencies from a specific distribution pocket (e.g. updates, security, proposed).\nThe '<series>-<pocket>' suite will be enabled on archive sources when resolving build-dependencies."))
                .arg(arg!(--ppa <ppa> "Build the package adding a specific PPA for dependencies (can be specified multiple times)")
                    .long_help("Build the package adding a specific PPA for dependencies. Can be specified multiple times.").required(false).action(clap::ArgAction::Append))
                .arg(arg!(--inject <package> "Inject a package into the build environment (can be specified multiple times)")
                    .long_help("Inject a package into the build environment before build-dep. Can be a .deb file path, a package name from the archive, or a package from a previously added PPA. Can be specified multiple times.").required(false).action(clap::ArgAction::Append))
                .arg(arg!(--cross "Cross-compile for target architecture (instead of qemu-binfmt)")
                    .long_help("Cross-compile for target architecture (instead of using qemu-binfmt)\nNote that most packages cannot be cross-compiled").required(false))
                .arg(arg!(--mode <mode> "Change build mode [local]").required(false)
                    .long_help("Change build mode [local]\nDefault will chose depending on other parameters, don't provide if unsure"))
                .arg(arg!(--verbose "Show raw tool output instead of the live build view").required(false)
                    .long_help("Show raw tool output instead of the live build view.\nAlso implied by RUST_LOG=debug for pkh's own logs.")),
        )
        .subcommand(
            Command::new("context")
                .about("Manage contexts")
                .subcommand_required(true)
                .subcommand(
                    Command::new("create")
                        .about("Create a new context")
                        .arg(arg!(<name> "Context name"))
                        .arg(arg!(--type <type> "Context type: ssh (only type supported for now)"))
                        .arg(arg!(--endpoint <endpoint> "Context endpoint (for example: ssh://user@host:port)"))
                )
                .subcommand(
                    Command::new("rm")
                        .about("Remove a context")
                        .arg(arg!(<name> "Context name"))
                )
                .subcommand(
                    Command::new("ls")
                        .about("List contexts")
                )
                .subcommand(Command::new("show").about("Show current context"))
                .subcommand(
                    Command::new("use")
                        .about("Set current context")
                        .arg(arg!(<name> "Context name"))
                )
        )
        .subcommand(
            Command::new("prune")
                .about("Prune residual pkh build artifacts and caches")
                // NOTE: --dry-run is defined via the builder API because clap's
                // `arg!` macro mis-tokenizes hyphenated long names (it would
                // parse `--dry-run` as long="dry" plus a spurious short flag,
                // tripping the "Short flags should precede long flags" assert).
                .arg(
                    clap::Arg::new("dry_run")
                        .long("dry-run")
                        .action(clap::ArgAction::SetTrue)
                        .help("List what would be removed without removing anything"),
                )
                .arg(
                    clap::Arg::new("all")
                        .long("all")
                        .action(clap::ArgAction::SetTrue)
                        .help("Also remove cached chroot tarballs (expensive to re-download)"),
                )
        )
        .get_matches();

    match matches.subcommand() {
        Some(("pull", sub_matches)) => {
            let package = sub_matches.get_one::<String>("package").expect("required");
            let series = sub_matches.get_one::<String>("series").map(|s| s.as_str());
            let dist = sub_matches.get_one::<String>("dist").map(|s| s.as_str());
            let version = sub_matches.get_one::<String>("version").map(|s| s.as_str());
            let ppa = sub_matches.get_one::<String>("ppa").map(|s| s.as_str());
            let pocket = sub_matches
                .get_one::<String>("pocket")
                .map(|s| s.as_str())
                .unwrap_or("");
            let archive = sub_matches.get_one::<bool>("archive").unwrap_or(&false);

            let (pb, progress_callback) = pkh::ui::create_progress_bar(&multi);

            // Convert PPA to base URL if provided
            let base_url = ppa.and_then(|ppa_str| {
                // PPA format: user/ppa_name
                let parts: Vec<&str> = ppa_str.split('/').collect();
                if parts.len() == 2 {
                    Some(pkh::package_info::ppa_to_base_url(parts[0], parts[1]))
                } else {
                    None
                }
            });

            // Since pull is async, we need to block on it
            if let Err(e) = rt.block_on(async {
                let package_info = pkh::package_info::lookup(
                    package,
                    version,
                    series,
                    pocket,
                    dist,
                    base_url.as_deref(),
                    Some(&progress_callback),
                )
                .await?;
                pkh::pull::pull(&package_info, None, Some(&progress_callback), *archive).await
            }) {
                pb.finish_and_clear();
                error!("{}", e);
                std::process::exit(1);
            }
            pb.finish_and_clear();
            multi.remove(&pb);
            info!("Done.");
        }
        Some(("chlog", sub_matches)) => {
            let cwd = current_dir_or_exit();
            let version = sub_matches.get_one::<String>("version").map(|s| s.as_str());
            let cli_series = sub_matches.get_one::<String>("series").map(|s| s.as_str());

            // Determine target series: CLI flag > interactive selector > current changelog series
            let target_series = if let Some(s) = cli_series {
                Some(s.to_string())
            } else {
                // Parse current changelog to determine the default series
                let changelog_path = cwd.join("debian/changelog");
                match pkh::changelog::parse_changelog_header(&changelog_path) {
                    Ok((_pkg, _ver, current_series)) => {
                        // Try to get the list of available series for this distribution
                        match rt.block_on(async {
                            let dist =
                                pkh::distro_info::get_dist_from_series(&current_series).await?;
                            pkh::distro_info::get_ordered_series_name(&dist).await
                        }) {
                            Ok(series_list) => {
                                match pkh::ui::select_series(&series_list, &current_series) {
                                    Ok(selected) => Some(selected),
                                    Err(e) => {
                                        error!(
                                            "Series selection failed: {}. Using current series '{}' instead.",
                                            e, current_series
                                        );
                                        Some(current_series)
                                    }
                                }
                            }
                            Err(_) => {
                                // Could not fetch series list, use current series as default
                                Some(current_series)
                            }
                        }
                    }
                    Err(_) => None,
                }
            };

            if let Err(e) = generate_entry(
                "debian/changelog",
                Some(&cwd),
                version,
                target_series.as_deref(),
            ) {
                error!("{}", e);
                std::process::exit(1);
            }

            let editor = match std::env::var("EDITOR") {
                Ok(e) => e,
                Err(_) => {
                    error!(
                        "No editor configured. Set the EDITOR environment variable \
                         (e.g. `EDITOR=nano` or `export EDITOR=vim`) and retry."
                    );
                    std::process::exit(1);
                }
            };
            let _status = std::process::Command::new(&editor)
                .current_dir(&cwd)
                .args(["debian/changelog"])
                .status()
                .map_err(|e| {
                    error!(
                        "Could not launch editor '{}': {}. \
                         Make sure it is installed and available on PATH.",
                        editor, e
                    );
                    std::process::exit(1);
                });
        }
        Some(("build", _sub_matches)) => {
            let cwd = current_dir_or_exit();
            if let Err(e) = pkh::build::build_source_package(Some(&cwd)) {
                error!("{}", e);
                // Unmet build dependencies/conflicts exit with status 3,
                // like dpkg-buildpackage does.
                if e.downcast_ref::<pkh::debian::deps::UnmetBuildDependencies>()
                    .is_some()
                {
                    std::process::exit(3);
                }
                std::process::exit(1);
            }
        }
        Some(("deb", sub_matches)) => {
            let cwd = current_dir_or_exit();
            let series = sub_matches.get_one::<String>("series").map(|s| s.as_str());
            let pocket = sub_matches.get_one::<String>("pocket").map(|s| s.as_str());
            let arch = sub_matches.get_one::<String>("arch").map(|s| s.as_str());
            let cross = sub_matches.get_one::<bool>("cross").unwrap_or(&false);
            let ppa: Vec<&str> = sub_matches
                .get_many::<String>("ppa")
                .map(|v| v.map(|s| s.as_str()).collect())
                .unwrap_or_default();
            let ppa = if ppa.is_empty() {
                None
            } else {
                Some(ppa.as_slice())
            };
            let inject_packages: Vec<&str> = sub_matches
                .get_many::<String>("inject")
                .map(|v| v.map(|s| s.as_str()).collect())
                .unwrap_or_default();
            let inject_packages = if inject_packages.is_empty() {
                None
            } else {
                Some(inject_packages.as_slice())
            };
            let mode: Option<&str> = sub_matches.get_one::<String>("mode").map(|s| s.as_str());
            let mode: Option<pkh::deb::BuildMode> = match mode {
                Some("local") => Some(pkh::deb::BuildMode::Local),
                _ => None,
            };
            let verbose = sub_matches
                .get_one::<bool>("verbose")
                .copied()
                .unwrap_or(false);

            // Live build view: disabled by --verbose or when stdout is not a
            // terminal (DebUi handles the non-TTY case itself)
            let ui = if verbose {
                None
            } else {
                Some(std::sync::Arc::new(pkh::ui::deb::DebUi::new(&multi)))
            };

            let result = rt.block_on(async {
                pkh::deb::build_binary_package(
                    arch,
                    series,
                    pocket,
                    Some(cwd.as_path()),
                    *cross,
                    mode,
                    ppa,
                    inject_packages,
                    None,
                    ui.clone(),
                )
                .await
            });

            match result {
                Ok(artifacts) => {
                    let _ = artifacts;
                    info!("Done.");
                }
                Err(e) => {
                    error!("{}", e);
                    std::process::exit(1);
                }
            }
        }
        Some(("context", sub_matches)) => {
            let mgr = pkh::context::manager();

            match sub_matches.subcommand() {
                Some(("create", args)) => {
                    let name = args.get_one::<String>("name").unwrap();
                    let type_str = args
                        .get_one::<String>("type")
                        .map(|s| s.as_str())
                        .unwrap_or("local");

                    let context = match type_str {
                        "local" => ContextConfig::Local,
                        "ssh" => {
                            let endpoint =
                                args.get_one::<String>("endpoint").unwrap_or_else(|| {
                                    error!(
                                        "An --endpoint is required to create an ssh context. \
                                         Expected format: [ssh://][user@]host[:port]"
                                    );
                                    std::process::exit(1);
                                });

                            // Parse host, user, port from endpoint
                            // Formats: [ssh://][user@]host[:port]
                            let endpoint_re = regex::Regex::new(r"^(?:ssh://)?(?:(?P<user>[^@]+)@)?(?P<host>[^:/]+)(?::(?P<port>\d+))?$").unwrap();
                            let endpoint_cap = endpoint_re.captures(endpoint).unwrap_or_else(|| {
                                error!("Invalid endpoint format: '{}'. Expected [ssh://][user@]host[:port]", endpoint);
                                std::process::exit(1);
                            });

                            let host = endpoint_cap.name("host").unwrap().as_str().to_string();
                            let user = endpoint_cap.name("user").map(|m| m.as_str().to_string());
                            let port = endpoint_cap.name("port").map(|m| {
                                m.as_str().parse::<u16>().unwrap_or_else(|_| {
                                    error!("Invalid port number");
                                    std::process::exit(1);
                                })
                            });

                            ContextConfig::Ssh { host, user, port }
                        }
                        _ => {
                            error!("Unknown context type: {}", type_str);
                            std::process::exit(1);
                        }
                    };

                    if let Err(e) = mgr.add_context(name, context) {
                        error!("Failed to create context: {}", e);
                        std::process::exit(1);
                    }
                    info!("Context '{}' created.", name);
                }
                Some(("rm", args)) => {
                    let name = args.get_one::<String>("name").unwrap();
                    if let Err(e) = mgr.remove_context(name) {
                        error!("Failed to remove context: {}", e);
                        std::process::exit(1);
                    }
                    info!("Context '{}' removed.", name);
                }
                Some(("ls", _)) => {
                    let contexts = mgr.list_contexts();
                    let current = mgr.current_name();
                    for ctx in contexts {
                        if ctx == current {
                            println!("* {}", ctx);
                        } else {
                            println!("  {}", ctx);
                        }
                    }
                }
                Some(("show", _)) => {}
                Some(("use", args)) => {
                    let name = args.get_one::<String>("name").unwrap();
                    if let Err(e) = mgr.set_current(name) {
                        error!("Failed to set context: {}", e);
                        std::process::exit(1);
                    }
                    info!("Switched to context '{}'.", name);
                }
                _ => unreachable!(),
            }
        }
        Some(("prune", sub_matches)) => {
            let dry_run = sub_matches
                .get_one::<bool>("dry_run")
                .copied()
                .unwrap_or(false);
            let all = sub_matches.get_one::<bool>("all").copied().unwrap_or(false);

            let options = pkh::prune::PruneOptions { dry_run, all };
            match pkh::prune::prune(options) {
                Ok(report) => {
                    if report.is_empty() {
                        info!("Nothing to prune.");
                    } else {
                        let action = if report.dry_run {
                            "Would remove"
                        } else {
                            "Removed"
                        };
                        for path in &report.removed {
                            info!("{} {}", action, path.display());
                        }
                        for (path, err) in &report.failed {
                            error!("Failed to remove {}: {}", path.display(), err);
                        }
                        if report.dry_run {
                            info!(
                                "(dry run) {} item(s) would be removed.",
                                report.removed.len()
                            );
                        } else {
                            info!(
                                "Pruned {} item(s){} ({} failure(s)).",
                                report.removed.len(),
                                if all {
                                    " including cached chroot tarballs"
                                } else {
                                    ""
                                },
                                report.failed.len()
                            );
                        }
                    }
                    if !report.failed.is_empty() {
                        std::process::exit(1);
                    }
                }
                Err(e) => {
                    error!("{}", e);
                    std::process::exit(1);
                }
            }
        }
        _ => unreachable!("Exhausted list of subcommands and subcommand_required prevents `None`"),
    }
}