use comrak::plugins::syntect::SyntectAdapterBuilder;
use comrak::{markdown_to_html_with_plugins, Options, Plugins};
use std::fs;
use std::path::Path;

pub fn render_markdown(content: String) -> String {
    let adapter = SyntectAdapterBuilder::new()
        .theme("base16-ocean.dark")
        .build();
    let options = Options::default();
    let mut plugins = Plugins::default();
    plugins.render.codefence_syntax_highlighter = Some(&adapter);
    markdown_to_html_with_plugins(&content, &options, &plugins)
}

pub fn convert_file(path: String) -> Result<String, String> {
    let content = fs::read_to_string(&path).map_err(|e| e.to_string())?;

    let adapter = SyntectAdapterBuilder::new()
        .theme("InspiredGitHub")
        .build();

    let mut options = Options::default();
    options.extension.table = true;
    options.extension.strikethrough = true;
    options.extension.autolink = true;
    options.extension.tasklist = true;

    let mut plugins = Plugins::default();
    plugins.render.codefence_syntax_highlighter = Some(&adapter);

    Ok(markdown_to_html_with_plugins(&content, &options, &plugins))
}

pub(crate) fn collect_md_files(dir: &Path, result: &mut Vec<String>) -> std::io::Result<()> {
    for entry in fs::read_dir(dir)? {
        let entry = entry?;
        let name = entry.file_name();
        if name.to_string_lossy().starts_with('.') {
            continue;
        }
        let path = entry.path();
        if path.is_dir() {
            collect_md_files(&path, result)?;
        } else if path.extension().is_some_and(|e| e == "md") {
            if let Some(s) = path.to_str() {
                result.push(s.to_string());
            }
        }
    }
    Ok(())
}

pub fn list_md_files(dir: String) -> Result<Vec<String>, String> {
    let path = Path::new(&dir);
    if !path.is_dir() {
        return Err(format!("{dir} n'est pas un dossier"));
    }
    let mut files = Vec::new();
    collect_md_files(path, &mut files).map_err(|e| e.to_string())?;
    files.sort();
    Ok(files)
}

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

    fn tmpdir(name: &str) -> PathBuf {
        std::env::temp_dir().join(name)
    }

    #[test]
    fn render_markdown_heading() {
        let html = render_markdown("# Hello\n".to_string());
        assert!(html.contains("<h1>"));
        assert!(html.contains("Hello"));
    }

    #[test]
    fn render_markdown_code_block() {
        let html = render_markdown("```rust\nfn main() {}\n```\n".to_string());
        assert!(html.contains("<code") || html.contains("<pre>"));
    }

    #[test]
    fn render_markdown_empty() {
        let html = render_markdown(String::new());
        assert!(!html.contains("<h1>"));
    }

    #[test]
    fn convert_file_success() {
        let dir = tmpdir("pena_convert_success");
        fs::create_dir_all(&dir).unwrap();
        let file = dir.join("test.md");
        fs::write(&file, "# Title\n\nParagraph.").unwrap();
        let result = convert_file(file.to_string_lossy().to_string());
        fs::remove_dir_all(&dir).unwrap();
        assert!(result.is_ok());
        assert!(result.unwrap().contains("<h1>"));
    }

    #[test]
    fn convert_file_with_table() {
        let dir = tmpdir("pena_convert_table");
        fs::create_dir_all(&dir).unwrap();
        let file = dir.join("table.md");
        fs::write(&file, "| A | B |\n|---|---|\n| 1 | 2 |").unwrap();
        let result = convert_file(file.to_string_lossy().to_string());
        fs::remove_dir_all(&dir).unwrap();
        assert!(result.is_ok());
        assert!(result.unwrap().contains("<table>"));
    }

    #[test]
    fn convert_file_not_found() {
        let result = convert_file("/nonexistent/path/does/not/exist.md".to_string());
        assert!(result.is_err());
    }

    #[test]
    fn collect_md_flat() {
        let dir = tmpdir("pena_collect_flat");
        fs::create_dir_all(&dir).unwrap();
        fs::write(dir.join("a.md"), "").unwrap();
        fs::write(dir.join("b.md"), "").unwrap();
        fs::write(dir.join("c.txt"), "").unwrap();
        let mut result = Vec::new();
        collect_md_files(&dir, &mut result).unwrap();
        result.sort();
        fs::remove_dir_all(&dir).unwrap();
        assert_eq!(result.len(), 2);
        assert!(result[0].ends_with("a.md"));
        assert!(result[1].ends_with("b.md"));
    }

    #[test]
    fn collect_md_recursive() {
        let dir = tmpdir("pena_collect_recursive");
        let sub = dir.join("docs");
        fs::create_dir_all(&sub).unwrap();
        fs::write(dir.join("Home.md"), "").unwrap();
        fs::write(sub.join("Page.md"), "").unwrap();
        let mut result = Vec::new();
        collect_md_files(&dir, &mut result).unwrap();
        fs::remove_dir_all(&dir).unwrap();
        assert_eq!(result.len(), 2);
    }

    #[test]
    fn collect_md_ignores_hidden_dir() {
        let dir = tmpdir("pena_collect_hidden_dir");
        let hidden = dir.join(".hidden");
        fs::create_dir_all(&hidden).unwrap();
        fs::write(dir.join("visible.md"), "").unwrap();
        fs::write(hidden.join("secret.md"), "").unwrap();
        let mut result = Vec::new();
        collect_md_files(&dir, &mut result).unwrap();
        fs::remove_dir_all(&dir).unwrap();
        assert_eq!(result.len(), 1);
        assert!(result[0].ends_with("visible.md"));
    }

    #[test]
    fn collect_md_ignores_hidden_file() {
        let dir = tmpdir("pena_collect_hidden_file");
        fs::create_dir_all(&dir).unwrap();
        fs::write(dir.join("visible.md"), "").unwrap();
        fs::write(dir.join(".hidden.md"), "").unwrap();
        let mut result = Vec::new();
        collect_md_files(&dir, &mut result).unwrap();
        fs::remove_dir_all(&dir).unwrap();
        assert_eq!(result.len(), 1);
        assert!(result[0].ends_with("visible.md"));
    }

    #[test]
    fn collect_md_nonexistent_dir() {
        let mut result = Vec::new();
        let err = collect_md_files(Path::new("/nonexistent/path/for/pena"), &mut result);
        assert!(err.is_err());
    }

    #[test]
    fn list_md_files_sorted() {
        let dir = tmpdir("pena_list_sorted");
        fs::create_dir_all(&dir).unwrap();
        fs::write(dir.join("z.md"), "").unwrap();
        fs::write(dir.join("a.md"), "").unwrap();
        fs::write(dir.join("m.md"), "").unwrap();
        let result = list_md_files(dir.to_string_lossy().to_string()).unwrap();
        fs::remove_dir_all(&dir).unwrap();
        assert_eq!(result.len(), 3);
        assert!(result[0] < result[1] && result[1] < result[2]);
    }

    #[test]
    fn list_md_files_not_a_dir() {
        let result = list_md_files("/nonexistent/does/not/exist".to_string());
        assert!(result.is_err());
    }
}