use anyhow::{bail, Context, Result};
use ngit::{
    client::send_events,
    git_events::{is_event_proposal_root_for_branch, tag_value},
};
use nostr_sdk::PublicKey;

use crate::{
    cli::{extract_signer_cli_arguments, Cli},
    client::{
        fetching_with_report, get_all_proposal_patch_events_from_cache,
        get_proposals_and_revisions_from_cache, get_repo_ref_from_cache, Client, Connect,
    },
    git::{identify_ahead_behind, str_to_sha1, Repo, RepoActions},
    git_events::{
        generate_patch_event, get_commit_id_from_patch, get_most_recent_patch_with_ancestors,
    },
    login,
    repo_ref::get_repo_coordinates,
    sub_commands,
};

#[derive(Debug, clap::Args)]
pub struct SubCommandArgs {
    #[arg(long, action)]
    /// send proposal revision from checked out proposal branch
    force: bool,
}

#[allow(clippy::too_many_lines)]
pub async fn launch(cli_args: &Cli, args: &SubCommandArgs) -> Result<()> {
    let git_repo = Repo::discover().context("failed to find a git repository")?;
    let git_repo_path = git_repo.get_path()?;

    let (main_or_master_branch_name, _) = git_repo
        .get_main_or_master_branch()
        .context("no main or master branch")?;

    let root_commit = git_repo
        .get_root_commit()
        .context("failed to get root commit of the repository")?;

    let branch_name = git_repo
        .get_checked_out_branch_name()
        .context("failed to get checked out branch name")?;

    if branch_name == main_or_master_branch_name {
        bail!("checkout a branch associated with a proposal first")
    }
    let mut client = Client::default();

    let repo_coordinates = get_repo_coordinates(&git_repo, &client).await?;

    fetching_with_report(git_repo_path, &client, &repo_coordinates).await?;

    let repo_ref = get_repo_ref_from_cache(Some(git_repo_path), &repo_coordinates).await?;

    let logged_in_public_key =
        if let Ok(Some(npub)) = git_repo.get_git_config_item("nostr.npub", None) {
            PublicKey::parse(npub).ok()
        } else {
            None
        };

    let proposal_root_event =
        get_proposals_and_revisions_from_cache(git_repo_path, repo_ref.coordinates())
            .await?
            .iter()
            .find(|e| {
                is_event_proposal_root_for_branch(e, &branch_name, &logged_in_public_key)
                    .unwrap_or(false)
            })
            .context("failed to find proposal that matches the current branch name")?
            .clone();

    let commit_events =
        get_all_proposal_patch_events_from_cache(git_repo_path, &repo_ref, &proposal_root_event.id)
            .await?;

    let most_recent_proposal_patch_chain = get_most_recent_patch_with_ancestors(commit_events)
        .context("failed to get most recent patch for proposal")?;

    let branch_tip = git_repo.get_tip_of_branch(&branch_name)?;

    let most_recent_patch_commit_id = str_to_sha1(
        &get_commit_id_from_patch(
            most_recent_proposal_patch_chain
                .first()
                .context("no patches found")?,
        )
        .context("latest patch event doesnt have a commit tag")?,
    )
    .context("latest patch event commit tag isn't a valid SHA1 hash")?;

    let proposal_base_commit_id = str_to_sha1(
        &tag_value(
            most_recent_proposal_patch_chain
                .last()
                .context("no patches found")?,
            "parent-commit",
        )
        .context("patch is incorrectly formatted")?,
    )
    .context("latest patch event parent-commit tag isn't a valid SHA1 hash")?;

    if most_recent_patch_commit_id.eq(&branch_tip) {
        bail!("proposal already up-to-date with local branch");
    }

    if args.force {
        println!("preparing to force push proposal revision...");
        sub_commands::send::launch(
            cli_args,
            &sub_commands::send::SubCommandArgs {
                // if not ahead of master prompt, otherwise assume proposal revision is all commits
                // ahead
                since_or_range: if let Ok((_, _, ahead, _)) =
                    identify_ahead_behind(&git_repo, &None, &None)
                {
                    if ahead.is_empty() {
                        String::new()
                    } else {
                        format!("HEAD~{}", ahead.len())
                    }
                } else {
                    String::new()
                },
                in_reply_to: vec![proposal_root_event.id.to_string()],
                title: None,
                description: None,
                no_cover_letter: true,
            },
            true,
        )
        .await?;
        println!("force pushed proposal revision");
        return Ok(());
    }

    if most_recent_proposal_patch_chain.iter().any(|e| {
        let c = tag_value(e, "parent-commit").unwrap_or_default();
        c.eq(&branch_tip.to_string())
    }) {
        bail!("proposal is ahead of local branch");
    }

    let Ok((ahead, behind)) = git_repo
        .get_commits_ahead_behind(&most_recent_patch_commit_id, &branch_tip)
        .context("the latest patch in proposal doesnt share an ancestor with your branch.")
    else {
        if git_repo.ancestor_of(&proposal_base_commit_id, &branch_tip)? {
            bail!("local unpublished proposal ammendments. consider force pushing.");
        }
        bail!("local unpublished proposal has been rebased. consider force pushing");
    };

    if !behind.is_empty() {
        bail!(
            "your local proposal branch is {} behind patches on nostr. consider rebasing or force pushing",
            behind.len()
        )
    }

    println!(
        "{} commits ahead. preparing to create creating patch events.",
        ahead.len()
    );

    let (signer, user_ref, _) = login::login_or_signup(
        &Some(&git_repo),
        &extract_signer_cli_arguments(cli_args).unwrap_or(None),
        &cli_args.password,
        Some(&client),
    )
    .await?;

    let mut patch_events: Vec<nostr::Event> = vec![];
    for commit in &ahead {
        patch_events.push(
            generate_patch_event(
                &git_repo,
                &root_commit,
                commit,
                Some(proposal_root_event.id),
                &signer,
                &repo_ref,
                patch_events.last().map(|e| e.id),
                None,
                None,
                &None,
                &[],
            )
            .await
            .context("failed to make patch event from commit")?,
        );
    }
    println!("pushing {} commits", ahead.len());

    client.set_signer(signer).await;

    send_events(
        &client,
        Some(git_repo_path),
        patch_events,
        user_ref.relays.write(),
        repo_ref.relays.clone(),
        !cli_args.disable_cli_spinners,
        false,
    )
    .await?;

    println!("pushed {} commits", ahead.len());

    Ok(())
}