use std::borrow::Cow;

use lazy_static::lazy_static;
use regex::{Captures, Regex};

use crate::config::Config;
use crate::features::OptionValueFunction;
use crate::git_config::{GitConfigEntry, GitRemoteRepo};

pub fn make_feature() -> Vec<(String, OptionValueFunction)> {
    builtin_feature!([
        (
            "hyperlinks",
            bool,
            None,
            _opt => true
        )
    ])
}

pub fn format_commit_line_with_osc8_commit_hyperlink<'a>(
    line: &'a str,
    config: &Config,
) -> Cow<'a, str> {
    if let Some(GitConfigEntry::GitRemote(GitRemoteRepo::GitHubRepo(repo))) =
        config.git_config_entries.get("remote.origin.url")
    {
        COMMIT_LINE_REGEX.replace(line, |captures: &Captures| {
            format_commit_line_captures_with_osc8_commit_hyperlink(captures, repo)
        })
    } else {
        Cow::from(line)
    }
}

/// Create a file hyperlink to `path`, displaying `text`.
pub fn format_osc8_file_hyperlink<'a>(
    relative_path: &'a str,
    line_number: Option<usize>,
    text: &str,
    config: &Config,
) -> Cow<'a, str> {
    if let Some(GitConfigEntry::Path(workdir)) = config.git_config_entries.get("delta.__workdir__")
    {
        let absolute_path = workdir.join(relative_path);
        let mut url = config
            .hyperlinks_file_link_format
            .replace("{path}", &absolute_path.to_string_lossy());
        if let Some(n) = line_number {
            url = url.replace("{line}", &format!("{}", n))
        } else {
            url = url.replace("{line}", "")
        };
        Cow::from(format!(
            "{osc}8;;{url}{st}{text}{osc}8;;{st}",
            url = url,
            text = text,
            osc = "\x1b]",
            st = "\x1b\\"
        ))
    } else {
        Cow::from(relative_path)
    }
}

lazy_static! {
    static ref COMMIT_LINE_REGEX: Regex = Regex::new("(.* )([0-9a-f]{40})(.*)").unwrap();
}

fn format_commit_line_captures_with_osc8_commit_hyperlink(
    captures: &Captures,
    github_repo: &str,
) -> String {
    let commit = captures.get(2).unwrap().as_str();
    format!(
        "{prefix}{osc}8;;{url}{st}{commit}{osc}8;;{st}{suffix}",
        url = format_github_commit_url(commit, github_repo),
        commit = commit,
        prefix = captures.get(1).unwrap().as_str(),
        suffix = captures.get(3).unwrap().as_str(),
        osc = "\x1b]",
        st = "\x1b\\"
    )
}

fn format_github_commit_url(commit: &str, github_repo: &str) -> String {
    format!("https://github.com/{}/commit/{}", github_repo, commit)
}