package com.xuqm.update.service;

import com.xuqm.update.model.AppPackageInspectResult;
import com.xuqm.update.model.RnBundleInspectResult;
import net.dongliu.apk.parser.ApkFile;
import net.dongliu.apk.parser.bean.ApkMeta;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;

import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.security.DigestInputStream;
import java.security.MessageDigest;
import java.util.Map;
import java.util.Locale;
import java.util.HexFormat;
import java.util.Optional;
import java.util.UUID;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;

@Service
public class UpdateAssetService {

    @Value("${update.upload-dir:/tmp/xuqm-update}")
    private String uploadDir;

    @Value("${update.base-url:https://update.dev.xuqinmin.com}")
    private String baseUrl;

    public String storeAppPackage(MultipartFile apkFile) throws IOException {
        if (apkFile == null || apkFile.isEmpty()) {
            return null;
        }
        String filename = UUID.randomUUID() + "_" + apkFile.getOriginalFilename();
        Path dir = Paths.get(uploadDir, "apk");
        Files.createDirectories(dir);
        Path dest = dir.resolve(filename);
        apkFile.transferTo(dest.toFile());
        return baseUrl + "/files/apk/" + filename;
    }

    public AppPackageInspectResult inspectAppPackage(MultipartFile packageFile) throws Exception {
        String fileName = Optional.ofNullable(packageFile != null ? packageFile.getOriginalFilename() : null)
                .orElse("");
        String normalized = fileName.toLowerCase(Locale.ROOT);
        if (packageFile == null || packageFile.isEmpty()) {
            return new AppPackageInspectResult(platformFromFileName(fileName), null, null, null, fileName, false);
        }

        Path temp = Files.createTempFile("xuqm-package-inspect-", suffixFor(fileName));
        try {
            try (InputStream in = packageFile.getInputStream()) {
                Files.copy(in, temp, StandardCopyOption.REPLACE_EXISTING);
            }

            if (normalized.endsWith(".apk")) {
                return inspectApk(temp, fileName);
            }
            if (normalized.endsWith(".ipa")) {
                return inspectIpa(temp, fileName);
            }
            return new AppPackageInspectResult(platformFromFileName(fileName), null, null, null, fileName, false);
        } finally {
            Files.deleteIfExists(temp);
        }
    }

    public RnBundleInspectResult inspectRnBundle(MultipartFile bundle) throws Exception {
        String fileName = Optional.ofNullable(bundle != null ? bundle.getOriginalFilename() : null)
                .orElse("");
        if (bundle == null || bundle.isEmpty()) {
            return new RnBundleInspectResult(null, null, null, null, fileName, false);
        }
        return inspectRnBundleName(fileName);
    }

    public StoredRnBundle storeRnBundle(String appId, String platform, String moduleId, MultipartFile bundle) throws Exception {
        if (bundle == null || bundle.isEmpty()) {
            throw new IllegalArgumentException("bundle file is required");
        }
        String filename = moduleId + "." + platform.toLowerCase() + ".bundle";
        Path dir = Paths.get(uploadDir, "rn", appId, platform.toLowerCase(), moduleId);
        Files.createDirectories(dir);
        Path dest = dir.resolve(filename);

        String md5 = computeMd5(bundle);
        bundle.transferTo(dest.toFile());
        return new StoredRnBundle(dest.toAbsolutePath().toString(), md5);
    }

    private String computeMd5(MultipartFile file) throws Exception {
        MessageDigest digest = MessageDigest.getInstance("MD5");
        try (DigestInputStream dis = new DigestInputStream(file.getInputStream(), digest)) {
            byte[] buf = new byte[8192];
            while (dis.read(buf) != -1) {
                // read fully
            }
        }
        return HexFormat.of().formatHex(digest.digest());
    }

    private AppPackageInspectResult inspectApk(Path file, String fileName) throws Exception {
        try (ApkFile apk = new ApkFile(file.toFile())) {
            ApkMeta meta = apk.getApkMeta();
            Integer versionCode = meta.getVersionCode() == null ? null : meta.getVersionCode().intValue();
            return new AppPackageInspectResult(
                    "ANDROID",
                    blankToNull(meta.getPackageName()),
                    blankToNull(meta.getVersionName()),
                    versionCode,
                    fileName,
                    true);
        }
    }

    private AppPackageInspectResult inspectIpa(Path file, String fileName) throws Exception {
        try (ZipFile zipFile = new ZipFile(file.toFile())) {
            ZipEntry entry = zipFile.stream()
                    .filter(e -> e.getName().endsWith("Info.plist"))
                    .findFirst()
                    .orElse(null);
            if (entry != null) {
                byte[] data = zipFile.getInputStream(entry).readAllBytes();
                String text = new String(data, StandardCharsets.UTF_8);
                if (text.contains("<plist")) {
                    var plist = parsePlistXml(text);
                    return new AppPackageInspectResult(
                            "IOS",
                            blankToNull(plist.get("CFBundleIdentifier")),
                            blankToNull(plist.get("CFBundleShortVersionString")),
                            parseInteger(plist.get("CFBundleVersion")),
                            fileName,
                            true);
                }
            }
        }
        return new AppPackageInspectResult("IOS", null, null, null, fileName, false);
    }

    private RnBundleInspectResult inspectRnBundleName(String fileName) {
        String baseName = stripExtension(fileName);
        String[] parts = baseName.split("__");
        if (parts.length >= 4) {
            return new RnBundleInspectResult(
                    blankToNull(parts[0]),
                    platformFromToken(parts[1]),
                    blankToNull(parts[2]),
                    blankToNull(parts[3]),
                    fileName,
                    true);
        }
        return new RnBundleInspectResult(
                null,
                platformFromFileName(fileName),
                null,
                null,
                fileName,
                false);
    }

    private Map<String, String> parsePlistXml(String xml) throws Exception {
        DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
        factory.setNamespaceAware(false);
        factory.setExpandEntityReferences(false);
        Document document = factory.newDocumentBuilder().parse(new java.io.ByteArrayInputStream(xml.getBytes(StandardCharsets.UTF_8)));
        NodeList dictNodes = document.getElementsByTagName("dict");
        if (dictNodes.getLength() == 0) {
            return Map.of();
        }
        Element dict = (Element) dictNodes.item(0);
        Map<String, String> values = new java.util.LinkedHashMap<>();
        Node child = dict.getFirstChild();
        String currentKey = null;
        while (child != null) {
            if (child.getNodeType() == Node.ELEMENT_NODE) {
                String nodeName = child.getNodeName();
                if ("key".equals(nodeName)) {
                    currentKey = child.getTextContent();
                } else if (currentKey != null && ("string".equals(nodeName) || "integer".equals(nodeName))) {
                    values.put(currentKey, child.getTextContent());
                    currentKey = null;
                }
            }
            child = child.getNextSibling();
        }
        return values;
    }

    private String platformFromFileName(String fileName) {
        String lower = Optional.ofNullable(fileName).orElse("").toLowerCase(Locale.ROOT);
        if (lower.contains("ios") || lower.endsWith(".ipa")) {
            return "IOS";
        }
        return "ANDROID";
    }

    private String platformFromToken(String token) {
        if (token == null) {
            return null;
        }
        String normalized = token.trim().toUpperCase(Locale.ROOT);
        return switch (normalized) {
            case "ANDROID", "IOS" -> normalized;
            case "A", "ANDROIDSDK" -> "ANDROID";
            case "I", "IOSSDK" -> "IOS";
            default -> normalized.isBlank() ? null : normalized;
        };
    }

    private String stripExtension(String fileName) {
        if (fileName == null) return "";
        int idx = fileName.lastIndexOf('.');
        return idx > 0 ? fileName.substring(0, idx) : fileName;
    }

    private String suffixFor(String fileName) {
        if (fileName == null) return ".tmp";
        int idx = fileName.lastIndexOf('.');
        return idx > 0 ? fileName.substring(idx) : ".tmp";
    }

    private Integer parseInteger(String value) {
        if (value == null || value.isBlank()) return null;
        try {
            return Integer.valueOf(value.trim());
        } catch (NumberFormatException e) {
            return null;
        }
    }

    private String blankToNull(String value) {
        return value == null || value.isBlank() ? null : value.trim();
    }

    public record StoredRnBundle(String bundlePath, String md5) {}
}