use super::PackageManager;
use os_info::{Info, Type};
use serde::Deserialize;
use serde_yaml::Value;
use tokio::process::Command;

#[derive(Clone)]
pub struct Pacman;

#[derive(Deserialize)]
struct PacmanRepo {
    name: String,
    server: String,
    cacheserver: Option<String>,
    siglevel: Option<SigLevel>,
    keyid: Option<String>,
    keypackage: Option<String>,
}

struct SigLevel {
    raw: String,
}

impl SigLevel {
    pub fn new(raw: String) -> Self {
        for token in raw.split_whitespace() {
            if !VALID_SIGLEVEL_TOKENS.contains(&token) {
                log::warn!("Invalid siglevel token: {}", token);
            }
        }
        Self { raw }
    }
}

impl std::fmt::Display for SigLevel {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}", self.raw)
    }
}

impl<'de> Deserialize<'de> for SigLevel {
    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
    where
        D: serde::Deserializer<'de>,
    {
        let s = String::deserialize(deserializer)?;
        Ok(SigLevel::new(s))
    }
}

const VALID_SIGLEVEL_TOKENS: &[&str] = &[
    // Token
    "Never",
    "Optional",
    "Required",
    "TrustedOnly",
    "TrustAll",
    // Package prefix
    "PackageNever",
    "PackageOptional",
    "PackageRequired",
    "PackageTrustedOnly",
    "PackageTrustAll",
    // Database prefix
    "DatabaseNever",
    "DatabaseOptional",
    "DatabaseRequired",
    "DatabaseTrustedOnly",
    "DatabaseTrustAll",
];

impl PackageManager for Pacman {
    fn name(&self) -> &'static str {
        "pacman"
    }

    fn adopt(&self, distro: &Info) -> bool {
        matches!(
            distro.os_type(),
            Type::Arch
                | Type::Manjaro
                | Type::EndeavourOS
                | Type::Garuda
                | Type::CachyOS
                | Type::Artix
                | Type::Mabox
                | Type::Nobara
                | Type::InstantOS
        )
    }

    fn binary(&self) -> &'static str {
        "pacman"
    }

    fn update(&self) -> Vec<Command> {
        let mut cmd = Command::new("pacman");
        cmd.arg("-Sy");
        vec![cmd]
    }

    fn install(&self, package: &[String]) -> Vec<Command> {
        let mut cmd = Command::new("pacman");
        cmd.arg("-S");
        cmd.arg("--noconfirm");
        cmd.arg("--needed");
        cmd.args(package);
        vec![cmd]
    }

    fn change_mirror(&self, repo: &str, _osinfo: Option<&Info>) -> Vec<Command> {
        let mirrorlist_path = "/etc/pacman.d/mirrorlist";

        let content = format!(
            "# Generated by WSExecutor-PM\n\
             # Date: $(date)\n\
             # Original content overwritten.\n\
             \n\
             Server = {}\n",
            repo
        );

        let mut cmd = Command::new("sh");
        cmd.arg("-c").arg(format!(
            "cat > {} << 'PACMAN_EOF'\n{}\nPACMAN_EOF",
            mirrorlist_path, content
        ));

        let mut keyring_cmd = Command::new("sh");
            keyring_cmd.arg("-c").arg("pacman-key --init");
        vec![cmd, keyring_cmd]
    }

    fn add_repository(&self, repo: &Value, _osinfo: Option<&Info>) -> Vec<Command> {
        let repos: Vec<PacmanRepo> = match serde_yaml::from_value(repo.clone()) {
            Ok(r) => r,
            Err(e) => {
                log::error!("Failed to parse pacman repository: {}", e);
                return Vec::new();
            }
        };
        let pacman_conf = "/etc/pacman.conf";
        let mut content = String::with_capacity(512);
        content.push_str("# Modified by HBW baker\n");
        let mut cmds = vec![];
        for repo in &repos {
            // Install keyring
            if repo.keyid.is_some() && repo.keypackage.is_some() {
                log::error!(
                    "Both keyid and keypackage are set for repository {}",
                    repo.name
                );
                log::warn!("Ignoring...");
                continue;
            }
            if let Some(keyid) = &repo.keyid {
                let mut cmd = Command::new("sh");
                cmd.arg("-c")
                    .arg(format!("pacman-key --recv-keys {}", keyid));
                cmds.push(cmd);
                let mut cmd = Command::new("sh");
                cmd.arg("-c")
                    .arg(format!("pacman-key --lsign-key {}", keyid));
                cmds.push(cmd);
            } else if let Some(keypackage) = &repo.keypackage {
                let mut cmd = Command::new("sh");
                cmd.arg("-c")
                    .arg(format!("pacman -Sy {} --needed --noconfirm", keypackage));
                cmds.push(cmd);
            }

            // Configure repository
            let mut block = format!("[{}]\n", &repo.name);
            block.push_str(&format!("Server = {}\n", &repo.server));

            if let Some(cacheserver) = &repo.cacheserver {
                block.push_str(&format!("CacheServer = {}\n", cacheserver));
            }
            if let Some(siglevel) = &repo.siglevel {
                block.push_str(&format!("SigLevel = {}\n", siglevel));
            }
            content.push_str(&block);
        }

        let mut cmd = Command::new("sh");
        cmd.arg("-c").arg(format!(
            "cat >> {} << 'PACMAN_EOF'\n{}\nPACMAN_EOF",
            pacman_conf, content
        ));
        cmds.insert(0, cmd);

        cmds
    }
}

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

    #[test]
    fn test_name() {
        let pacman = Pacman;
        assert_eq!(pacman.name(), "pacman");
    }

    #[test]
    fn test_binary() {
        let pacman = Pacman;
        assert_eq!(pacman.binary(), "pacman");
    }

    #[test]
    fn test_adopt_true_for_arch_based_distros() {
        let pacman = Pacman;
        let arch_distros = [
            Type::Arch,
            Type::Manjaro,
            Type::EndeavourOS,
            Type::Garuda,
            Type::CachyOS,
            Type::Artix,
            Type::Mabox,
            Type::Nobara,
            Type::InstantOS,
        ];
        for distro in arch_distros {
            let info = Info::with_type(distro);
            assert!(
                pacman.adopt(&info),
                "Pacman should adopt distro: {:?}",
                distro
            );
        }
    }

    #[test]
    fn test_adopt_false_for_non_arch_distros() {
        let pacman = Pacman;
        let non_arch_distros = [
            Type::Ubuntu,
            Type::Debian,
            Type::Fedora,
            Type::CentOS,
            Type::RedHatEnterprise,
            Type::openSUSE,
            Type::Gentoo,
            Type::FreeBSD,
            Type::Macos,
            Type::Windows,
        ];
        for distro in non_arch_distros {
            let info = Info::with_type(distro);
            assert!(
                !pacman.adopt(&info),
                "Pacman should NOT adopt distro: {:?}",
                distro
            );
        }
    }

    #[test]
    fn test_update_command_contents() {
        let cmds = Pacman.update();
        let cmd = cmds[0].as_std();
        assert_eq!(cmd.get_program().to_string_lossy(), "pacman");
        let args: Vec<String> = cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        assert_eq!(args, vec!["-Sy"]);
    }

    #[test]
    fn test_install_command_contents() {
        let cmds = Pacman.install(&["curl".to_string(), "wget".to_string()]);
        let cmd = cmds[0].as_std();
        assert_eq!(cmd.get_program().to_string_lossy(), "pacman");
        let args: Vec<String> = cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        assert_eq!(args, vec!["-S", "--noconfirm", "--needed", "curl", "wget"]);
    }

    #[test]
    fn test_install_single_package() {
        let cmds = Pacman.install(&["package".to_string()]);
        let cmd = cmds[0].as_std();
        let args: Vec<String> = cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        assert_eq!(args, vec!["-S", "--noconfirm", "--needed", "package"]);
    }

    #[test]
    fn test_siglevel_valid_tokens() {
        let siglevel = SigLevel::new("Never".to_string());
        assert_eq!(siglevel.to_string(), "Never");

        let siglevel = SigLevel::new("Optional Required".to_string());
        assert_eq!(siglevel.to_string(), "Optional Required");

        let siglevel = SigLevel::new("PackageOptional DatabaseRequired".to_string());
        assert_eq!(siglevel.to_string(), "PackageOptional DatabaseRequired");
    }

    #[test]
    fn test_siglevel_with_invalid_tokens() {
        // Invalid tokens are logged but still accepted
        let siglevel = SigLevel::new("Never InvalidToken".to_string());
        assert_eq!(siglevel.to_string(), "Never InvalidToken");
    }

    #[test]
    fn test_siglevel_deserialize() {
        let yaml = "Never";
        let siglevel: SigLevel = serde_yaml::from_str(yaml).unwrap();
        assert_eq!(siglevel.to_string(), "Never");

        let yaml = "PackageOptional DatabaseRequired";
        let siglevel: SigLevel = serde_yaml::from_str(yaml).unwrap();
        assert_eq!(siglevel.to_string(), "PackageOptional DatabaseRequired");
    }

    #[test]
    fn test_siglevel_all_valid_tokens() {
        let all_tokens = VALID_SIGLEVEL_TOKENS.join(" ");
        let siglevel = SigLevel::new(all_tokens.clone());
        assert_eq!(siglevel.to_string(), all_tokens);
    }

    #[test]
    fn test_change_mirror_command() {
        let cmds = Pacman.change_mirror("https://mirror.example.com/archlinux", None);
        let cmd = cmds[0].as_std();
        assert_eq!(cmd.get_program().to_string_lossy(), "sh");
        let args: Vec<String> = cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        let full_arg = args.join(" ");
        assert!(full_arg.contains("cat > /etc/pacman.d/mirrorlist"));
        assert!(full_arg.contains("https://mirror.example.com/archlinux"));
    }

    #[test]
    fn test_add_repository_single_repo() {
        let repo_yaml = serde_yaml::from_value(serde_yaml::Value::Sequence(vec![
            serde_yaml::Value::Mapping(
                [
                    (
                        serde_yaml::Value::String("name".to_string()),
                        serde_yaml::Value::String("customrepo".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("server".to_string()),
                        serde_yaml::Value::String("https://repo.example.com".to_string()),
                    ),
                ]
                .into_iter()
                .collect(),
            ),
        ]))
        .unwrap();

        let cmds = Pacman.add_repository(&repo_yaml, None);
        // Should have at least one command (the one to append to pacman.conf)
        assert!(!cmds.is_empty());
        let last_cmd = cmds.last().unwrap().as_std();
        let args: Vec<String> = last_cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        let full_arg = args.join(" ");
        assert!(full_arg.contains("cat >> /etc/pacman.conf"));
        assert!(full_arg.contains("[customrepo]"));
        assert!(full_arg.contains("https://repo.example.com"));
    }

    #[test]
    fn test_add_repository_with_siglevel() {
        let repo_yaml = serde_yaml::from_value(serde_yaml::Value::Sequence(vec![
            serde_yaml::Value::Mapping(
                [
                    (
                        serde_yaml::Value::String("name".to_string()),
                        serde_yaml::Value::String("customrepo".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("server".to_string()),
                        serde_yaml::Value::String("https://repo.example.com".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("siglevel".to_string()),
                        serde_yaml::Value::String("PackageOptional".to_string()),
                    ),
                ]
                .into_iter()
                .collect(),
            ),
        ]))
        .unwrap();

        let cmds = Pacman.add_repository(&repo_yaml, None);
        let last_cmd = cmds.last().unwrap().as_std();
        let args: Vec<String> = last_cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        let full_arg = args.join(" ");
        assert!(full_arg.contains("SigLevel = PackageOptional"));
    }

    #[test]
    fn test_add_repository_with_keyid() {
        let repo_yaml = serde_yaml::from_value(serde_yaml::Value::Sequence(vec![
            serde_yaml::Value::Mapping(
                [
                    (
                        serde_yaml::Value::String("name".to_string()),
                        serde_yaml::Value::String("customrepo".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("server".to_string()),
                        serde_yaml::Value::String("https://repo.example.com".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("keyid".to_string()),
                        serde_yaml::Value::String("ABCDEF123456".to_string()),
                    ),
                ]
                .into_iter()
                .collect(),
            ),
        ]))
        .unwrap();

        let cmds = Pacman.add_repository(&repo_yaml, None);
        // Should have 3 commands: recv-keys, lsign-key, and append to conf
        assert_eq!(cmds.len(), 3);

        let recv_cmd = cmds[1].as_std();
        let recv_args: Vec<String> = recv_cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();

        assert!(recv_args
            .join(" ")
            .contains("pacman-key --recv-keys ABCDEF123456"));

        let lsign_cmd = cmds[2].as_std();
        let lsign_args: Vec<String> = lsign_cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        assert!(lsign_args
            .join(" ")
            .contains("pacman-key --lsign-key ABCDEF123456"));
    }

    #[test]
    fn test_add_repository_with_keypackage() {
        let repo_yaml = serde_yaml::from_value(serde_yaml::Value::Sequence(vec![
            serde_yaml::Value::Mapping(
                [
                    (
                        serde_yaml::Value::String("name".to_string()),
                        serde_yaml::Value::String("customrepo".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("server".to_string()),
                        serde_yaml::Value::String("https://repo.example.com".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("keypackage".to_string()),
                        serde_yaml::Value::String("gnupg".to_string()),
                    ),
                ]
                .into_iter()
                .collect(),
            ),
        ]))
        .unwrap();

        let cmds = Pacman.add_repository(&repo_yaml, None);
        // Should have 2 commands: install keypackage and append to conf
        assert_eq!(cmds.len(), 2);

        let install_cmd = cmds[1].as_std();
        let install_args: Vec<String> = install_cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        assert!(install_args
            .join(" ")
            .contains("pacman -Sy gnupg --needed --noconfirm"));
    }

    #[test]
    fn test_add_repository_with_cacheserver() {
        let repo_yaml = serde_yaml::from_value(serde_yaml::Value::Sequence(vec![
            serde_yaml::Value::Mapping(
                [
                    (
                        serde_yaml::Value::String("name".to_string()),
                        serde_yaml::Value::String("customrepo".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("server".to_string()),
                        serde_yaml::Value::String("https://repo.example.com".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("cacheserver".to_string()),
                        serde_yaml::Value::String("https://cache.example.com".to_string()),
                    ),
                ]
                .into_iter()
                .collect(),
            ),
        ]))
        .unwrap();

        let cmds = Pacman.add_repository(&repo_yaml, None);
        let last_cmd = cmds.last().unwrap().as_std();
        let args: Vec<String> = last_cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        let full_arg = args.join(" ");
        assert!(full_arg.contains("CacheServer = https://cache.example.com"));
    }

    #[test]
    fn test_add_repository_multiple_repos() {
        let repos_yaml = serde_yaml::from_value(serde_yaml::Value::Sequence(vec![
            serde_yaml::Value::Mapping(
                [
                    (
                        serde_yaml::Value::String("name".to_string()),
                        serde_yaml::Value::String("repo1".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("server".to_string()),
                        serde_yaml::Value::String("https://repo1.example.com".to_string()),
                    ),
                ]
                .into_iter()
                .collect(),
            ),
            serde_yaml::Value::Mapping(
                [
                    (
                        serde_yaml::Value::String("name".to_string()),
                        serde_yaml::Value::String("repo2".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("server".to_string()),
                        serde_yaml::Value::String("https://repo2.example.com".to_string()),
                    ),
                ]
                .into_iter()
                .collect(),
            ),
        ]))
        .unwrap();

        let cmds = Pacman.add_repository(&repos_yaml, None);
        let last_cmd = cmds.last().unwrap().as_std();
        let args: Vec<String> = last_cmd
            .get_args()
            .map(|a| a.to_string_lossy().into_owned())
            .collect();
        let full_arg = args.join(" ");
        assert!(full_arg.contains("[repo1]"));
        assert!(full_arg.contains("[repo2]"));
    }

    #[test]
    fn test_add_repository_both_keyid_and_keypackage_logs_error() {
        let repo_yaml = serde_yaml::from_value(serde_yaml::Value::Sequence(vec![
            serde_yaml::Value::Mapping(
                [
                    (
                        serde_yaml::Value::String("name".to_string()),
                        serde_yaml::Value::String("customrepo".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("server".to_string()),
                        serde_yaml::Value::String("https://repo.example.com".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("keyid".to_string()),
                        serde_yaml::Value::String("ABCDEF123456".to_string()),
                    ),
                    (
                        serde_yaml::Value::String("keypackage".to_string()),
                        serde_yaml::Value::String("gnupg".to_string()),
                    ),
                ]
                .into_iter()
                .collect(),
            ),
        ]))
        .unwrap();

        let cmds = Pacman.add_repository(&repo_yaml, None);
        // Should have no key-related commands when both are set (error case)
        assert!(cmds.is_empty() || cmds.len() == 1); // Only the conf append cmd if any
    }

    #[test]
    fn test_add_repository_invalid_yaml_returns_empty() {
        let invalid_yaml = serde_yaml::Value::String("invalid: [yaml".to_string());
        let cmds = Pacman.add_repository(&invalid_yaml, None);
        assert!(cmds.is_empty());
    }
}