#!/usr/bin/env python3

from pathlib import Path
from datetime import datetime
import re
import shutil
import sys

ROOT = Path("/home/nvme/dockerdata/prove/s152js")
MANAGER = ROOT / "helpers/hlsManager.js"
ROUTE = ROOT / "routes/hls.js"


def replace_once(text, pattern, replacement, label, flags=0):
    new_text, count = re.subn(
        pattern, replacement, text, count=1, flags=flags
    )
    if count != 1:
        raise RuntimeError(
            f"{label}: attesa 1 sostituzione, trovate {count}. "
            "File non modificati."
        )
    print(f"[OK] {label}")
    return new_text


def main():
    if not MANAGER.is_file() or not ROUTE.is_file():
        sys.exit(f"ERRORE: file non trovati sotto {ROOT}")

    manager = MANAGER.read_text(encoding="utf-8")
    route = ROUTE.read_text(encoding="utf-8")

    # 1. Stato esplicito del job.
    manager = replace_once(
        manager,
        r"notified:\s*false,",
        "notified: false,\n"
        "    ready: false,\n"
        "    status: 'processing',",
        "Stato iniziale del job",
    )

    # 2. Il poller dichiara il job pronto solo alla soglia richiesta.
    manager = replace_once(
        manager,
        r"if\s*\(\s*tsCount\s*>=\s*job\.segmentsNeeded\s*\)"
        r"\s*\{\s*job\.notified\s*=\s*true;",
        "if (tsCount >= job.segmentsNeeded) {\n"
        "            job.ready = true;\n"
        "            job.status = 'ready';\n"
        "            job.notified = true;",
        "Soglia dei segmenti HLS",
    )

    # 3. Registra esplicitamente il timeout.
    timeout_start = manager.find("// Timeout")
    exit_start = manager.find("// FFmpeg exit", timeout_start)

    if timeout_start < 0 or exit_start < 0:
        raise RuntimeError("Blocco timeout non trovato. Nessun file scritto.")

    timeout_block = manager[timeout_start:exit_start]
    timeout_block = replace_once(
        timeout_block,
        r"job\.notified\s*=\s*true;",
        "job.notified = true;\n          job.status = 'timeout';",
        "Stato timeout",
    )
    manager = (
        manager[:timeout_start]
        + timeout_block
        + manager[exit_start:]
    )

    # 4. All'uscita di FFmpeg, non confondere fine conversione
    #    con buffer sufficiente per iniziare il casting.
    manager = replace_once(
        manager,
        r"let status;\s*"
        r"if\s*\(code === 0 && masterExists\)\s*\{\s*"
        r"status = 'finished';\s*"
        r"\}\s*else\s*\{\s*"
        r"status = 'error';\s*"
        r"\}\s*"
        r"job\.notified\s*=\s*true;",
        "const hasMinimumBuffer =\n"
        "            code === 0 &&\n"
        "            masterExists &&\n"
        "            tsCount >= job.segmentsNeeded;\n"
        "\n"
        "          if (hasMinimumBuffer) {\n"
        "            job.ready = true;\n"
        "          }\n"
        "\n"
        "          job.status = job.ready\n"
        "            ? 'ready'\n"
        "            : (code === 0 && masterExists\n"
        "                ? 'finished_insufficient_segments'\n"
        "                : 'error');\n"
        "\n"
        "          status = job.status;\n"
        "          job.notified = true;",
        "Controllo finale all'uscita di FFmpeg",
    )

    # 5. Conserva il job per due minuti dopo l'uscita di FFmpeg.
    manager = replace_once(
        manager,
        r"finally\s*\{\s*jobs\.delete\(\s*jobId\s*\);\s*\}",
        "finally {\n"
        "        job.finishedAt = Date.now();\n"
        "        setTimeout(() => {\n"
        "          jobs.delete(jobId);\n"
        "        }, 2 * 60 * 1000).unref();\n"
        "      }",
        "Conservazione temporanea del job",
    )

    # 6. Aggiunge il conteggio locale dei segmenti .ts alla route.
    route = replace_once(
        route,
        r"const router = express\.Router\(\);",
        "const router = express.Router();\n"
        "\n"
        "function countTsSegments(outDir) {\n"
        "  try {\n"
        "    return fs.readdirSync(outDir).filter(\n"
        "      name => name.toLowerCase().endsWith('.ts')\n"
        "    ).length;\n"
        "  } catch (err) {\n"
        "    return 0;\n"
        "  }\n"
        "}",
        "Conteggio segmenti nella route",
    )

    # 7. L'endpoint URL richiede almeno segmentsNeeded segmenti.
    route = replace_once(
        route,
        r"if\s*\(\s*"
        r"!job\.notified\s*\|\|\s*"
        r"!fs\.existsSync\(masterPath\)\s*"
        r"\)\s*\{\s*"
        r"return res\.status\(404\)\.json\(\{\s*"
        r"error:\s*'Playlist not yet ready'\s*"
        r"\}\);\s*"
        r"\}",
        "const tsCount = countTsSegments(job.outDir);\n"
        "\n"
        "  if (\n"
        "    !job.ready ||\n"
        "    !fs.existsSync(masterPath) ||\n"
        "    tsCount < job.segmentsNeeded\n"
        "  ) {\n"
        "    if (job.exitCode !== null) {\n"
        "      return res.status(409).json({\n"
        "        error: 'HLS finished before minimum buffer was ready',\n"
        "        status: job.status,\n"
        "        ready_segments: tsCount,\n"
        "        required_segments: job.segmentsNeeded\n"
        "      });\n"
        "    }\n"
        "\n"
        "    return res.status(404).json({\n"
        "      error: 'Playlist not yet ready',\n"
        "      ready_segments: tsCount,\n"
        "      required_segments: job.segmentsNeeded\n"
        "    });\n"
        "  }",
        "Controllo della soglia nell'endpoint URL",
        flags=re.S,
    )

    # Tutte le sostituzioni sono state verificate prima di scrivere.
    # Crea backup e poi salva entrambi i file.
    stamp = datetime.now().strftime("%Y%m%d_%H%M%S")
    backup_manager = MANAGER.with_name(
        f"hlsManager.js.bak_{stamp}"
    )
    backup_route = ROUTE.with_name(
        f"hls.js.bak_{stamp}"
    )

    shutil.copy2(MANAGER, backup_manager)
    shutil.copy2(ROUTE, backup_route)

    MANAGER.write_text(manager, encoding="utf-8")
    ROUTE.write_text(route, encoding="utf-8")

    print("\nModifiche applicate.")
    print(f"Backup: {backup_manager}")
    print(f"Backup: {backup_route}")
    print("\nVerifica ora la sintassi JavaScript con:")
    print("node --check helpers/hlsManager.js")
    print("node --check routes/hls.js")


if __name__ == "__main__":
    main()