package com.thebrokenrail.freshcoffee.download;

import com.google.gson.Gson;
import com.google.gson.JsonSyntaxException;
import com.google.gson.annotations.SerializedName;
import com.thebrokenrail.freshcoffee.config.HardcodedConfig;
import com.thebrokenrail.freshcoffee.util.limit.LimitUtil;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

public final class AdoptOpenJDK {
    public static final class JDK {
        public Binary binary;
        public Version version;
    }

    @SuppressWarnings("unused")
    public static final class Binary {
        private String architecture;
        private String heap_size;
        private String image_type;
        private String os;
        @SerializedName("package")
        public Package packageObj;
        private String project;

        private boolean isValid() {
            return heap_size.equals("normal") && image_type.equals("jre") && project.equals("jdk") && (packageObj.link.endsWith(".zip") || packageObj.link.endsWith(".tar.gz"));
        }
    }

    @SuppressWarnings("unused")
    public static final class Package {
        public String link;
        public int size;
    }

    @SuppressWarnings("unused")
    public static final class Version {
        public String semver;
    }

    private static String urlToString(@SuppressWarnings("SameParameterValue") String urlStr) {
        try {
            StringBuilder stringBuilder = new StringBuilder();
            URL url = new URL(urlStr);

            try (BufferedReader in = new BufferedReader(new InputStreamReader(url.openConnection().getInputStream()))) {
                String line;
                while ((line = in.readLine()) != null) {
                    stringBuilder.append(line);
                    stringBuilder.append('\n');
                }
            }

            return stringBuilder.toString();
        } catch (IOException e) {
            return null;
        }
    }

    private static class Platform {
        private final String os;
        private final String architecture;

        private Platform(String os, String architecture) {
            this.os = os;
            this.architecture = architecture;
        }

        private boolean isValid(JDK jdk) {
            return jdk.binary.os.equals(os) && jdk.binary.architecture.equals(architecture);
        }

        @Override
        public String toString() {
            return os + '-' + architecture;
        }
    }

    private static final String[] PLATFORM_TYPES = new String[]{"linux", "win", "macosx"};
    private static final String[] ARCHITECTURE_TYPES = new String[]{"x64", "i686", "aarch64", "arm32"};

    private static final Platform[] PLATFORMS;

    static {
        PLATFORMS = new Platform[PLATFORM_TYPES.length * ARCHITECTURE_TYPES.length];
        int pos = 0;
        for (String platformType : PLATFORM_TYPES) {
            for (String architectureType : ARCHITECTURE_TYPES) {
                PLATFORMS[pos++] = new Platform(platformType, architectureType);
            }
        }
    }

    public static Map<String, JDK> get() {
        String data = urlToString(String.format("https://api.adoptopenjdk.net/v3/assets/latest/%s/%s", LimitUtil.getMinimumJavaVersion().getValue(), HardcodedConfig.JAVA_IMPLEMENTATION));
        if (data != null) {
            JDK[] allJDKs = null;

            try {
                Gson gson = new Gson();
                allJDKs = gson.fromJson(data, JDK[].class);
            } catch (JsonSyntaxException ignored) {
            }

            if (allJDKs != null) {
                Map<String, JDK> selectedJDKs = new HashMap<>();
                for (JDK jdk : allJDKs) {
                    if (jdk.binary.isValid()) {
                        Platform platform = null;
                        for (Platform option : PLATFORMS) {
                            if (option.isValid(jdk)) {
                                platform = option;
                                break;
                            }
                        }

                        if (platform != null) {
                            selectedJDKs.put(platform.toString(), jdk);
                        }
                    }
                }
                return selectedJDKs;
            }
        }
        return Collections.emptyMap();
    }
}