// Command transcript-tail is a minimal terminal client for transcriptor-ai's
// live SSE transcript endpoint — connects, parses each `data: {...}` event,
// and prints just the text, instead of raw JSON (`curl -N` works too, but
// isn't pleasant to read live). See CLAUDE.md for the SSE message format.
package main

import (
	"bufio"
	"encoding/json"
	"flag"
	"fmt"
	"net/http"
	"os"
	"strings"

	"github.com/stephanetailland/transcriptor-ai/internal/transcript"
)

func main() {
	if err := run(); err != nil {
		fmt.Fprintln(os.Stderr, "transcript-tail:", err)
		os.Exit(1)
	}
}

func run() error {
	url := flag.String("url", "http://localhost:8420/events", "transcriptor-ai SSE endpoint to follow")
	flag.Parse()

	resp, err := http.Get(*url)
	if err != nil {
		return fmt.Errorf("connect: %w", err)
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("unexpected status: %s", resp.Status)
	}

	scanner := bufio.NewScanner(resp.Body)
	for scanner.Scan() {
		data, ok := strings.CutPrefix(scanner.Text(), "data: ")
		if !ok {
			continue // SSE keep-alive/blank lines, comments, etc.
		}
		var msg transcript.Message
		if err := json.Unmarshal([]byte(data), &msg); err != nil {
			continue
		}
		printMessage(msg)
	}
	// The connection ending here — whether cleanly or as a network-level
	// error — almost always just means the transcriptor-ai server stopped.
	// We can't reliably tell that apart from a real connection problem, so
	// don't be alarmist about it: this isn't a failure of transcript-tail
	// itself, the way a startup connection error (above) is.
	fmt.Fprintln(os.Stderr, "transcript-tail: stream ended (server stopped?)")
	return nil
}

func printMessage(msg transcript.Message) {
	marker := " "
	if !msg.IsFinal {
		marker = "…" // still a partial hypothesis, may be revised
	}
	fmt.Printf("[%s%s] %s\n", msg.Track, marker, msg.Text)
}