// n34 - A CLI to interact with NIP-34 and other stuff related to codes in nostr
// Copyright (C) 2025 Awiteb <a@4rs.nl>
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <https://gnu.org/licenses/gpl-3.0.html>.

use convert_case::{Case, Casing};
use nostr::{
    event::{EventBuilder, EventId, Tag, TagKind, TagStandard, Tags},
    key::PublicKey,
    nips::{
        nip01::Coordinate,
        nip21::Nip21,
        nip34::{GitIssue, GitRepositoryAnnouncement},
    },
    parser::Token,
    types::{RelayUrl, Url},
};

use crate::error::{N34Error, N34Result};


/// A trait to add helper instance function to [`Tags`] type
#[easy_ext::ext(TagsExt)]
impl Tags {
    /// Search for the given tag and map it value to a function
    pub fn map_tag<T>(&self, kind: TagKind, f: impl FnOnce(&TagStandard) -> T) -> Option<T> {
        self.find_standardized(kind).map(f)
    }

    /// Search for the given tag and map it value to a function. If the tag not
    /// found return the default `T`
    pub fn dmap_tag<T>(&self, kind: TagKind, f: impl FnOnce(&TagStandard) -> T) -> T
    where
        T: Default,
    {
        self.map_tag(kind, f).unwrap_or_default()
    }

    /// Finds the first standard tag of the given kind with the specified
    /// marker, then applies the function to the tag and returns the result.
    pub fn map_marker<T>(
        &self,
        kind: TagKind,
        marker: &str,
        f: impl FnOnce(&TagStandard) -> T,
    ) -> Option<T> {
        self.filter_standardized(kind)
            .find(|t| (*t).clone().to_vec().last().is_some_and(|m| m == marker))
            .map(f)
    }
}

/// Trait for building [`GitRepositoryAnnouncement`] events
#[easy_ext::ext(NewGitRepositoryAnnouncement)]
impl EventBuilder {
    /// Creates a new [`GitRepositoryAnnouncement`] event builder with the given
    /// repository details.
    #[allow(clippy::too_many_arguments)]
    pub fn new_git_repo(
        repo_id: String,
        name: Option<String>,
        description: Option<String>,
        web: Vec<Url>,
        clone: Vec<Url>,
        relays: Vec<RelayUrl>,
        maintainers: Vec<PublicKey>,
        labels: Vec<String>,
        force_id: bool,
    ) -> N34Result<EventBuilder> {
        let repo_id = repo_id.trim();
        let kebab_repo_id = repo_id.to_case(Case::Kebab);
        if repo_id.is_empty() || (!force_id && repo_id != kebab_repo_id) {
            if repo_id != kebab_repo_id {
                tracing::error!(
                    "The repo id should be `{kebab_repo_id}` (kebab-case). Use `--force-id` to \
                     override this check"
                );
            }
            return Err(N34Error::InvalidRepoId);
        }

        Ok(
            EventBuilder::git_repository_announcement(GitRepositoryAnnouncement {
                id: repo_id.to_owned(),
                name,
                description,
                web,
                clone,
                relays,
                euc: None,
                maintainers,
            })?
            .tags(labels.into_iter().map(Tag::hashtag)),
        )
    }

    /// Creates a new [`GitIssue`] event builder with the given
    /// issue details.
    pub fn new_git_issue(
        repository: Coordinate,
        content: String,
        subject: Option<String>,
        labels: Vec<String>,
    ) -> N34Result<EventBuilder> {
        EventBuilder::git_issue(GitIssue {
            repository,
            content,
            subject,
            labels: labels.into_iter().map(|l| l.trim().to_owned()).collect(),
        })
        .map_err(N34Error::from)
    }
}

/// Helper functions for [`Token`] type
#[easy_ext::ext(TokenUtils)]
impl Token<'_> {
    /// Returns `Some((public_key, relays))` from the givin token if it's npub1
    /// or nprofile1
    pub fn extract_public_key(&self) -> Option<(PublicKey, Vec<RelayUrl>)> {
        match self {
            Token::Nostr(nip21) => {
                match nip21 {
                    Nip21::Pubkey(pkey) => Some((*pkey, Vec::new())),
                    Nip21::Profile(profile) => Some((profile.public_key, profile.relays.clone())),
                    _ => None,
                }
            }
            _ => None,
        }
    }

    /// Returns `Some((note_id, relays))` from the givin token if it's note1 or
    /// nevent1
    pub fn extract_event_id(&self) -> Option<(EventId, Vec<RelayUrl>)> {
        match self {
            Token::Nostr(nip21) => {
                match nip21 {
                    Nip21::EventId(event_id) => Some((*event_id, Vec::new())),
                    Nip21::Event(event) => Some((event.event_id, event.relays.clone())),
                    _ => None,
                }
            }
            _ => None,
        }
    }

    /// Returns `Some(hashtag)` from the givin token if it's a hashtag
    pub fn extract_hashtag(&self) -> Option<String> {
        match self {
            Token::Hashtag(tag) => Some(tag.trim().to_owned()),
            _ => None,
        }
    }
}