1 files changed, 589 insertions, 0 deletions

diff --git a/src/downloader.rs b/src/downloader.rs
new file mode 100644
index 0000000..6d92166
--- /dev/null
+++ b/src/downloader.rs
@@ -0,0 +1,589 @@
+use std::collections::HashSet;
+use std::fs;
+use std::io::{Read, Write};
+use std::path::Path;
+
+use anyhow::{bail, Context, Result};
+use regex::Regex;
+use serde::Deserialize;
+
+// ---------------------------------------------------------------------------
+// Public event type for GUI progress reporting
+// ---------------------------------------------------------------------------
+
+#[cfg(feature = "gui")]
+use std::sync::mpsc;
+
+#[cfg(feature = "gui")]
+#[derive(Debug, Clone)]
+pub enum Event {
+    Log(String),
+    DownloadStart { name: String, total_bytes: u64 },
+    DownloadProgress { name: String, bytes: u64 },
+    DownloadComplete { name: String },
+    DownloadError { name: String, error: String },
+    Finished { success: bool, message: String },
+}
+
+// ---------------------------------------------------------------------------
+// API response types
+// ---------------------------------------------------------------------------
+
+#[derive(Deserialize)]
+pub struct ModInfo {
+    pub releases: Vec<Release>,
+}
+
+#[derive(Deserialize, Clone)]
+pub struct Release {
+    pub version: String,
+    pub info_json: Option<InfoJson>,
+}
+
+#[derive(Deserialize, Clone)]
+pub struct InfoJson {
+    #[serde(default)]
+    pub dependencies: Vec<String>,
+}
+
+// ---------------------------------------------------------------------------
+// Dependency model
+// ---------------------------------------------------------------------------
+
+#[derive(Debug, Clone, PartialEq)]
+pub enum DepType {
+    Base,
+    Required,
+    Optional,
+    Incompatible,
+}
+
+#[derive(Debug, Clone)]
+pub struct Dependency {
+    pub dep_type: DepType,
+    pub name: String,
+}
+
+// ---------------------------------------------------------------------------
+// Constants
+// ---------------------------------------------------------------------------
+
+pub const MODINFO_API: &str = "https://re146.dev/factorio/mods/modinfo";
+pub const DOWNLOAD_BASE: &str = "https://mods-storage.re146.dev";
+
+fn dep_regex() -> &'static Regex {
+    static RE: std::sync::LazyLock<Regex> = std::sync::LazyLock::new(|| {
+        Regex::new(
+            r"(?i)^((?:)|(?:\?)|(?:\(\?\))|(?:!)|(?:~))(?:\s?)([%\w\s-]+)(?:\s{0,})(?:((?:=>)|(?:==)|(?:=)|(?:<=)|(?:>=)|(?:<)|(?:>)|(?:))(?:\s{0,})((\d+\.\d+\.\d+)|(\d+\.\d+)))?$",
+        )
+        .unwrap()
+    });
+    &RE
+}
+
+// ---------------------------------------------------------------------------
+// Mod name extraction
+// ---------------------------------------------------------------------------
+
+pub fn extract_mod_name(url_or_name: &str) -> Result<String> {
+    let re = Regex::new(r"(?i)^https?://mods\.factorio\.com/mod/([^\s/#?]{1,})").unwrap();
+    if let Some(caps) = re.captures(url_or_name) {
+        return Ok(caps[1].to_string());
+    }
+
+    let re2 =
+        Regex::new(r"(?i)^https?://mods\.factorio\.com/mods/([^\s/]{1,})/([^\s/#?]{1,})").unwrap();
+    if let Some(caps) = re2.captures(url_or_name) {
+        return Ok(caps[2].to_string());
+    }
+
+    if !url_or_name.contains('/') && !url_or_name.starts_with("http") {
+        return Ok(url_or_name.to_string());
+    }
+
+    bail!("Could not extract mod name from: {url_or_name}")
+}
+
+// ---------------------------------------------------------------------------
+// API helpers
+// ---------------------------------------------------------------------------
+
+pub fn fetch_modinfo(mod_name: &str) -> Result<ModInfo> {
+    let url = format!("{MODINFO_API}?id={mod_name}");
+    let resp = ureq::get(&url)
+        .header("Accept", "application/json")
+        .call()
+        .with_context(|| format!("Failed to fetch mod info for {mod_name}"))?;
+
+    if resp.status().as_u16() == 404 {
+        bail!("Mod '{mod_name}' not found on the portal");
+    }
+
+    let body_text = resp
+        .into_body()
+        .read_to_string()
+        .with_context(|| format!("Failed to read response body for {mod_name}"))?;
+
+    let modinfo: ModInfo = serde_json::from_str(&body_text)
+        .with_context(|| format!("Failed to parse mod info JSON for {mod_name}"))?;
+
+    if modinfo.releases.is_empty() {
+        bail!("No releases found for '{mod_name}'");
+    }
+
+    Ok(modinfo)
+}
+
+/// Fetch available versions for a mod. Returns (version, display_label) pairs.
+#[cfg(feature = "gui")]
+pub fn fetch_versions(mod_name: &str) -> Result<Vec<(String, String)>> {
+    let modinfo = fetch_modinfo(mod_name)?;
+    let total = modinfo.releases.len();
+
+    let mut versions: Vec<(String, String)> = modinfo
+        .releases
+        .iter()
+        .enumerate()
+        .filter_map(|(i, r)| {
+            let v = r.version.clone();
+            if v.is_empty() {
+                return None;
+            }
+            let is_latest = i == total - 1;
+            let factorio_ver = r
+                .info_json
+                .as_ref()
+                .and_then(|j| j.dependencies.first())
+                .and_then(|d| {
+                    parse_dependency_string(d).and_then(|dep| {
+                        if dep.dep_type == DepType::Base && !dep.name.is_empty() {
+                            Some(dep.name)
+                        } else {
+                            None
+                        }
+                    })
+                })
+                .unwrap_or_default();
+
+            let mut label = v.clone();
+            if is_latest {
+                label.push_str(" (latest)");
+            }
+            if !factorio_ver.is_empty() {
+                label.push_str(&format!(" for {}", factorio_ver));
+            }
+            Some((v, label))
+        })
+        .collect();
+
+    versions.reverse();
+    Ok(versions)
+}
+
+pub fn find_release<'a>(modinfo: &'a ModInfo, target_version: Option<&str>) -> Option<&'a Release> {
+    match target_version {
+        Some(v) => modinfo.releases.iter().find(|r| r.version == v),
+        None => modinfo.releases.last(),
+    }
+}
+
+// ---------------------------------------------------------------------------
+// Dependency parsing
+// ---------------------------------------------------------------------------
+
+pub fn parse_dependency_string(input: &str) -> Option<Dependency> {
+    let re = dep_regex();
+    let caps = re.captures(input)?;
+
+    let name = caps[2].trim().to_string();
+
+    if name.eq_ignore_ascii_case("base") {
+        return Some(Dependency {
+            dep_type: DepType::Base,
+            name: "base".into(),
+        });
+    }
+
+    let dep_type = match &caps[1] {
+        "?" | "(?)" => DepType::Optional,
+        "!" => DepType::Incompatible,
+        _ => DepType::Required,
+    };
+
+    Some(Dependency {
+        dep_type,
+        name: name.trim().to_string(),
+    })
+}
+
+pub fn parse_dependencies(deps: &[String]) -> (Vec<Dependency>, Vec<Dependency>, Vec<Dependency>) {
+    let mut required = Vec::new();
+    let mut optional = Vec::new();
+    let mut incompatible = Vec::new();
+
+    for dep_str in deps.iter().rev() {
+        if let Some(dep) = parse_dependency_string(dep_str) {
+            match dep.dep_type {
+                DepType::Base => {}
+                DepType::Required => required.push(dep),
+                DepType::Optional => optional.push(dep),
+                DepType::Incompatible => incompatible.push(dep),
+            }
+        }
+    }
+
+    (required, optional, incompatible)
+}
+
+// ---------------------------------------------------------------------------
+// GUI download (channel-based)
+// ---------------------------------------------------------------------------
+
+#[cfg(feature = "gui")]
+fn gui_download_file(
+    url: &str,
+    file_path: &Path,
+    display_name: &str,
+    tx: &mpsc::Sender<Event>,
+) -> Result<()> {
+    let resp = ureq::get(url)
+        .call()
+        .with_context(|| format!("Failed to download {display_name}"))?;
+
+    let status = resp.status().as_u16();
+    if status == 404 {
+        bail!("File not found on storage: {display_name}");
+    }
+    if !(200..300).contains(&status) {
+        bail!("HTTP {status} while downloading {display_name}");
+    }
+
+    let total_size: u64 = resp
+        .headers()
+        .get("content-length")
+        .and_then(|v| v.to_str().ok())
+        .and_then(|v| v.parse().ok())
+        .unwrap_or(0);
+
+    let _ = tx.send(Event::DownloadStart {
+        name: display_name.to_string(),
+        total_bytes: total_size,
+    });
+
+    let mut reader = resp.into_body().into_reader();
+    let mut file = fs::File::create(file_path)
+        .with_context(|| format!("Failed to create file {}", file_path.display()))?;
+
+    let mut buf = [0u8; 256 * 1024];
+    let mut downloaded: u64 = 0;
+    loop {
+        let n = reader
+            .read(&mut buf)
+            .with_context(|| format!("Read error while downloading {display_name}"))?;
+        if n == 0 {
+            break;
+        }
+        file.write_all(&buf[..n])
+            .with_context(|| format!("Write error for {}", file_path.display()))?;
+        downloaded += n as u64;
+        let _ = tx.send(Event::DownloadProgress {
+            name: display_name.to_string(),
+            bytes: downloaded,
+        });
+    }
+
+    let _ = tx.send(Event::DownloadComplete {
+        name: display_name.to_string(),
+    });
+    Ok(())
+}
+
+#[cfg(feature = "gui")]
+fn gui_download_mod_with_deps(
+    mod_name: &str,
+    output: &Path,
+    target_version: Option<&str>,
+    include_optional: bool,
+    downloaded: &mut HashSet<String>,
+    analyzed: &mut HashSet<String>,
+    tx: &mpsc::Sender<Event>,
+) -> Result<()> {
+    if analyzed.contains(mod_name) {
+        return Ok(());
+    }
+
+    if mod_name == "space-age" {
+        let _ = tx.send(Event::Log(format!(
+            "Skipping reserved dependency '{mod_name}'"
+        )));
+        return Ok(());
+    }
+
+    let modinfo = fetch_modinfo(mod_name)?;
+
+    let release = find_release(&modinfo, target_version)
+        .with_context(|| format!("Version not found for '{mod_name}'"))?;
+
+    let version = &release.version;
+    let _ = tx.send(Event::Log(format!("Processing: {mod_name} v{version}")));
+    analyzed.insert(mod_name.to_string());
+
+    let file_name = format!("{mod_name}_{version}.zip");
+    let file_path = output.join(&file_name);
+
+    if !file_path.exists() {
+        fs::create_dir_all(output)?;
+        let download_url = format!("{DOWNLOAD_BASE}/{mod_name}/{version}.zip");
+
+        if let Err(e) = gui_download_file(&download_url, &file_path, &file_name, tx) {
+            let _ = tx.send(Event::DownloadError {
+                name: file_name.clone(),
+                error: e.to_string(),
+            });
+            return Err(e);
+        }
+        downloaded.insert(mod_name.to_string());
+    } else {
+        let _ = tx.send(Event::Log(format!("Already downloaded: {file_name}")));
+    }
+
+    if let Some(info_json) = &release.info_json {
+        let (required, optional, _incompatible) = parse_dependencies(&info_json.dependencies);
+
+        let mut deps = required;
+        if include_optional {
+            deps.extend(optional);
+        }
+
+        for dep in &deps {
+            if dep.name == "base" || downloaded.contains(&dep.name) || analyzed.contains(&dep.name)
+            {
+                continue;
+            }
+            let _ = tx.send(Event::Log(format!("-> Fetching dependency: {}", dep.name)));
+            if let Err(e) = gui_download_mod_with_deps(
+                &dep.name,
+                output,
+                None,
+                include_optional,
+                downloaded,
+                analyzed,
+                tx,
+            ) {
+                let _ = tx.send(Event::Log(format!(
+                    "Error processing dependency {}: {}",
+                    dep.name, e
+                )));
+            }
+        }
+    }
+
+    Ok(())
+}
+
+/// Entry point for GUI downloads. Runs the full pipeline and sends events via the channel.
+#[cfg(feature = "gui")]
+pub fn run_gui_download(
+    mod_url: &str,
+    output: &Path,
+    target_version: Option<String>,
+    include_optional: bool,
+    tx: mpsc::Sender<Event>,
+) {
+    let result = (|| -> Result<()> {
+        let mod_name = extract_mod_name(mod_url)?;
+        let _ = tx.send(Event::Log(format!("Starting download: {mod_name}")));
+
+        let mut downloaded = HashSet::new();
+        let mut analyzed = HashSet::new();
+
+        gui_download_mod_with_deps(
+            &mod_name,
+            output,
+            target_version.as_deref(),
+            include_optional,
+            &mut downloaded,
+            &mut analyzed,
+            &tx,
+        )?;
+
+        Ok(())
+    })();
+
+    match result {
+        Ok(()) => {
+            let _ = tx.send(Event::Finished {
+                success: true,
+                message: "All mods downloaded successfully.".into(),
+            });
+        }
+        Err(e) => {
+            let _ = tx.send(Event::Finished {
+                success: false,
+                message: format!("Download failed: {e}"),
+            });
+        }
+    }
+}
+
+// ---------------------------------------------------------------------------
+// CLI download (prints progress to stdout)
+// ---------------------------------------------------------------------------
+
+#[cfg(not(feature = "gui"))]
+fn cli_download_file(url: &str, file_path: &Path, display_name: &str) -> Result<()> {
+    let resp = ureq::get(url)
+        .call()
+        .with_context(|| format!("Failed to download {display_name}"))?;
+
+    let status = resp.status().as_u16();
+    if status == 404 {
+        bail!("File not found on storage: {display_name}");
+    }
+    if !(200..300).contains(&status) {
+        bail!("HTTP {status} while downloading {display_name}");
+    }
+
+    let total_size: u64 = resp
+        .headers()
+        .get("content-length")
+        .and_then(|v| v.to_str().ok())
+        .and_then(|v| v.parse().ok())
+        .unwrap_or(0);
+
+    println!(
+        "  Downloading: {display_name} ({:.1} MB)",
+        total_size as f64 / 1_048_576.0
+    );
+
+    let mut reader = resp.into_body().into_reader();
+    let mut file = fs::File::create(file_path)
+        .with_context(|| format!("Failed to create file {}", file_path.display()))?;
+
+    let mut buf = [0u8; 256 * 1024];
+    let mut downloaded: u64 = 0;
+    let mut last_pct: u32 = 0;
+    loop {
+        let n = reader
+            .read(&mut buf)
+            .with_context(|| format!("Read error while downloading {display_name}"))?;
+        if n == 0 {
+            break;
+        }
+        file.write_all(&buf[..n])
+            .with_context(|| format!("Write error for {}", file_path.display()))?;
+        downloaded += n as u64;
+
+        if total_size > 0 {
+            let pct = (downloaded * 100 / total_size) as u32;
+            if pct / 10 != last_pct / 10 {
+                last_pct = pct;
+                print!("\r  {} {}%", display_name, pct);
+                let _ = std::io::Write::flush(&mut std::io::stdout());
+            }
+        }
+    }
+    println!("\r  {} Done.", display_name);
+    Ok(())
+}
+
+#[cfg(not(feature = "gui"))]
+fn cli_download_mod_with_deps(
+    mod_name: &str,
+    output: &Path,
+    target_version: Option<&str>,
+    include_optional: bool,
+    downloaded: &mut HashSet<String>,
+    analyzed: &mut HashSet<String>,
+) -> Result<()> {
+    if analyzed.contains(mod_name) {
+        return Ok(());
+    }
+
+    if mod_name == "space-age" {
+        println!("Skipping reserved dependency '{mod_name}'");
+        return Ok(());
+    }
+
+    let modinfo = fetch_modinfo(mod_name)?;
+
+    let release = find_release(&modinfo, target_version)
+        .with_context(|| format!("Version not found for '{mod_name}'"))?;
+
+    let version = &release.version;
+    println!("Processing: {mod_name} v{version}");
+    analyzed.insert(mod_name.to_string());
+
+    let file_name = format!("{mod_name}_{version}.zip");
+    let file_path = output.join(&file_name);
+
+    if !file_path.exists() {
+        fs::create_dir_all(output)?;
+        let download_url = format!("{DOWNLOAD_BASE}/{mod_name}/{version}.zip");
+
+        if let Err(e) = cli_download_file(&download_url, &file_path, &file_name) {
+            eprintln!("Error downloading {file_name}: {e}");
+            return Err(e);
+        }
+        downloaded.insert(mod_name.to_string());
+    } else {
+        println!("Already downloaded: {file_name}");
+    }
+
+    if let Some(info_json) = &release.info_json {
+        let (required, optional, _incompatible) = parse_dependencies(&info_json.dependencies);
+
+        let mut deps = required;
+        if include_optional {
+            deps.extend(optional);
+        }
+
+        for dep in &deps {
+            if dep.name == "base" || downloaded.contains(&dep.name) || analyzed.contains(&dep.name)
+            {
+                continue;
+            }
+            println!("-> Fetching dependency: {}", dep.name);
+            if let Err(e) = cli_download_mod_with_deps(
+                &dep.name,
+                output,
+                None,
+                include_optional,
+                downloaded,
+                analyzed,
+            ) {
+                eprintln!("Error processing dependency {}: {}", dep.name, e);
+            }
+        }
+    }
+
+    Ok(())
+}
+
+/// Entry point for CLI downloads. Prints progress to stdout.
+#[cfg(not(feature = "gui"))]
+pub fn run_cli_download(
+    mod_url: &str,
+    output: &Path,
+    target_version: Option<&str>,
+    include_optional: bool,
+) -> Result<()> {
+    let mod_name = extract_mod_name(mod_url)?;
+    println!("Starting download: {mod_name}");
+    println!("Output directory: {}", output.display());
+
+    let mut downloaded = HashSet::new();
+    let mut analyzed = HashSet::new();
+
+    cli_download_mod_with_deps(
+        &mod_name,
+        output,
+        target_version,
+        include_optional,
+        &mut downloaded,
+        &mut analyzed,
+    )?;
+
+    println!("\nAll mods downloaded successfully.");
+    Ok(())
+}