#!/usr/bin/env nu
# Clean file watcher with signal-based exit

use utils.nu

# Clean file watcher that handles Ctrl+C gracefully
def main [config_file: string = "config/build.config.toml"] {
    # Load configuration
    let config = (open $config_file)
    let watch_files = [
        "src/index.html",
        "src/assets/css/modules/base.css",
        "src/assets/css/modules/components.css",
        "src/assets/css/modules/animations.css",
        "src/assets/css/modules/patterns.css",
        "src/assets/css/svg-data.css"
    ]

    print "👁️  Clean file watcher starting..."
    print "📝 Press Ctrl+C for clean exit"

    # Create stop signal file
    let stop_file = "/tmp/dev_watcher_stop"

    # Register signal handler using external process
    ^bash -c "trap 'touch /tmp/dev_watcher_stop' INT; while [ ! -f /tmp/dev_watcher_stop ]; do sleep 0.1; done" &

    mut initial_times = ($watch_files | each { |file|
        if ($file | path exists) {
            {
                file: $file,
                mtime: (ls $file | get modified | first)
            }
        }
    } | where ($it != null))

    # Main watch loop
    while not ($stop_file | path exists) {
        sleep 1sec

        let current_times = ($watch_files | each { |file|
            if ($file | path exists) {
                {
                    file: $file,
                    mtime: (ls $file | get modified | first)
                }
            }
        } | where ($it != null))

        let changed_pairs = ($current_times | zip $initial_times | where { |pair|
            $pair.0.mtime != $pair.1.mtime
        })

        if ($changed_pairs | length) > 0 {
            let changed_files = ($changed_pairs | each { |pair| $pair.0.file })
            print $"📝 Changed files: ($changed_files | str join ', ')"

            # Rebuild
            print "🔨 Rebuilding..."
            ^nu scripts/build.nu dev

            # Update times
            $initial_times = $current_times
        }
    }

    # Clean exit
    rm -f $stop_file
    print ""
    print "🛑 File watcher stopped cleanly"
}