// scholscan command-line tool
// this is the main entry point, commands are implemented in cmds/
// and basic logic in core/
package main

import (
	"errors"
	"flag"
	"fmt"
	"os"
	"scholscan/cmds"
	"scholscan/core"
)

func main() {
	if len(os.Args) < 2 {
		printHelp()
		os.Exit(1)
	}

	cmdName := os.Args[1]
	args := os.Args[2:]

	// handle the help stuff
	if cmdName == "help" || cmdName == "--help" || cmdName == "-h" {
		printHelp()
		return
	}

	// flag -> command
	var cmd core.Command
	switch cmdName {
	case "train":
		cmd = &cmds.TrainCommand{}
	case "scan":
		cmd = &cmds.ScanCommand{}
	case "serve":
		cmd = &cmds.ServeCommand{}
	default:
		fmt.Fprintf(os.Stderr, "Unknown command: %s\n\n", cmdName)
		printHelp()
		os.Exit(1)
	}

	// init the command, then run it
	if err := cmd.Init(args); err != nil {
		if errors.Is(err, flag.ErrHelp) {
			os.Exit(0)
		}
		fmt.Fprintf(os.Stderr, "Error initializing %s command: %v\n", cmdName, err)
		os.Exit(1)
	}

	if err := cmd.Run(os.Stdin, os.Stdout); err != nil {
		fmt.Fprintf(os.Stderr, "Error running %s command: %v\n", cmdName, err)
		os.Exit(1)
	}
}

func printHelp() {
	fmt.Printf(`scholscan <command> [arguments]

A command-line tool for filtering articles based on learned user preferences.

Commands:
    train           Train a model from positives and RSS feeds
    scan            Filter articles using a trained model
    serve           Start HTTP server with filtered RSS and scoring API

Usage:
    scholscan train POSITIVES_FILE --rss-feeds RSS_FEEDS_FILE > model.json
    scholscan scan --url RSS_URL --model MODEL > results.jsonl
    scholscan serve --model MODEL --rss-world RSS_FEEDS_FILE  # Start server
    scholscan serve --title "My Custom ScholScan"            # Custom title for web interface
    scholscan help                           # Show this help message

Examples:
    scholscan train positives.jsonl --rss-feeds rss_world.txt > model.json
    scholscan scan --url "https://feeds.reuters.com/reuters/topNews" --model model.json
    scholscan serve --port 8080 --model model.json --rss-world rss_world.txt

`)
}