mod pywal;
mod theme;
mod wallpaper;

use std::path::{Path, PathBuf};

use anyhow::{Context, Result, bail};

const IMAGE_EXTENSIONS: &[&str] = &["png", "jpg", "jpeg", "webp", "gif", "bmp"];

pub fn set(path: &Path) -> Result<()> {
    let path = validate(path)?;
    apply_wallpaper(&path)?;
    generate_palette(&path)?;
    reload_theme()?;
    Ok(())
}

pub fn get() -> Result<PathBuf> {
    let home = std::env::var("HOME").context("HOME not set")?;
    let wal_file = PathBuf::from(home).join(".cache/wal/wal");

    let contents = std::fs::read_to_string(&wal_file)
        .with_context(|| format!("no wallpaper set yet ({})", wal_file.display()))?;

    Ok(PathBuf::from(contents.trim()))
}

pub fn apply_wallpaper(path: &Path) -> Result<()> {
    wallpaper::apply(path)
}

pub fn generate_palette(path: &Path) -> Result<()> {
    pywal::generate(path)
}

pub fn reload_theme() -> Result<()> {
    theme::reload()
}

fn validate(path: &Path) -> Result<PathBuf> {
    let canonical = path
        .canonicalize()
        .with_context(|| format!("not found: {}", path.display()))?;

    let ext = canonical
        .extension()
        .and_then(|e| e.to_str())
        .unwrap_or("")
        .to_lowercase();

    if !IMAGE_EXTENSIONS.contains(&ext.as_str()) {
        bail!(
            "unsupported file type '.{}' — expected one of: {}",
            ext,
            IMAGE_EXTENSIONS.join(", ")
        );
    }

    Ok(canonical)
}