use super::*;

use anyhow::{Context, Result};
use std::collections::HashMap;

pub const EXTENSION_METADATA: &str = "__extension__";
pub const PATH_METADATA: &str = "__path__";

pub async fn load_recursive_url(
    loaders: &HashMap<String, String>,
    path: &str,
) -> Result<Vec<(String, RagMetadata)>> {
    let extension = RECURSIVE_URL_LOADER;
    let pages: Vec<Page> = match loaders.get(extension) {
        Some(loader_command) => {
            let contents = run_loader_command(path, extension, loader_command)?;
            serde_json::from_str(&contents).context(r#"The crawler response is invalid. It should follow the JSON format: `[{"path":"...", "text":"..."}]`."#)?
        }
        None => {
            let options = CrawlOptions::preset(path);
            crawl_website(path, options).await?
        }
    };
    let output = pages
        .into_iter()
        .map(|v| {
            let Page { path, text } = v;
            let mut metadata: RagMetadata = Default::default();
            metadata.insert(PATH_METADATA.into(), path);
            metadata.insert(EXTENSION_METADATA.into(), "md".into());
            (text, metadata)
        })
        .collect();
    Ok(output)
}

pub async fn load_file(
    loaders: &HashMap<String, String>,
    path: &str,
) -> Result<(String, RagMetadata)> {
    let extension = get_patch_extension(path).unwrap_or_else(|| DEFAULT_EXTENSION.into());
    match loaders.get(&extension) {
        Some(loader_command) => load_with_command(path, &extension, loader_command),
        None => load_plain(path, &extension).await,
    }
}

pub async fn load_url(
    loaders: &HashMap<String, String>,
    path: &str,
) -> Result<(String, RagMetadata)> {
    let (contents, extension) = fetch(loaders, path, false).await?;
    let mut metadata: RagMetadata = Default::default();
    metadata.insert(PATH_METADATA.into(), path.into());
    metadata.insert(EXTENSION_METADATA.into(), extension);
    Ok((contents, metadata))
}

async fn load_plain(path: &str, extension: &str) -> Result<(String, RagMetadata)> {
    let contents = tokio::fs::read_to_string(path).await?;
    let mut metadata: RagMetadata = Default::default();
    metadata.insert(PATH_METADATA.into(), path.to_string());
    metadata.insert(EXTENSION_METADATA.into(), extension.to_string());
    Ok((contents, metadata))
}

fn load_with_command(
    path: &str,
    extension: &str,
    loader_command: &str,
) -> Result<(String, RagMetadata)> {
    let contents = run_loader_command(path, extension, loader_command)?;
    let mut metadata: RagMetadata = Default::default();
    metadata.insert(PATH_METADATA.into(), path.to_string());
    metadata.insert(EXTENSION_METADATA.into(), DEFAULT_EXTENSION.to_string());
    Ok((contents, metadata))
}