package com.mrkayjaydee.playhours.events;

import com.mrkayjaydee.playhours.config.MOTDConfig;
import com.mrkayjaydee.playhours.core.ForceMode;
import com.mrkayjaydee.playhours.core.ScheduleService;
import com.mrkayjaydee.playhours.events.ScheduleFormatter.FormattedSchedule;
import com.mrkayjaydee.playhours.text.Messages;
import net.minecraft.ChatFormatting;
import net.minecraft.network.chat.Component;
import net.minecraft.network.chat.MutableComponent;

import java.time.ZonedDateTime;
import java.util.ArrayList;
import java.util.List;
import java.util.Optional;

/**
 * Builds MOTD components based on configuration.
 * Supports multiple MOTD strategies: rotating, custom lines, custom format, and automatic.
 */
public final class MOTDBuilder {
    private MOTDBuilder() {}

    private static int currentRotationIndex = 0;
    private static long lastRotationTime = 0;
    private static List<? extends String> lastRotationTemplates = null;

    /**
     * Builds the MOTD component based on configuration and current schedule state.
     * Priority: rotation → custom lines → custom format → automatic
     * 
     * @param scheduleService the schedule service
     * @param now the current time
     * @return the MOTD component
     */
    public static Component build(ScheduleService scheduleService, ZonedDateTime now) {
        // Check for rotation first
        if (MOTDConfig.ROTATION_ENABLED.get()) {
            List<? extends String> templates = MOTDConfig.ROTATION_TEMPLATES.get();
            if (templates != null && !templates.isEmpty()) {
                return buildRotating(scheduleService, now, templates);
            }
        }

        // Check for custom lines
        List<? extends String> customLines = MOTDConfig.CUSTOM_LINES.get();
        if (customLines != null && !customLines.isEmpty()) {
            return buildCustomLines(scheduleService, now, customLines);
        }

        // Check for custom format
        String customFormat = MOTDConfig.CUSTOM_FORMAT.get();
        if (customFormat != null && !customFormat.trim().isEmpty()) {
            return buildCustomFormat(scheduleService, now, customFormat);
        }

        // Build automatic MOTD
        return buildAutomatic(scheduleService, now);
    }

    /**
     * Builds a rotating MOTD that cycles through configured templates.
     */
    private static Component buildRotating(ScheduleService scheduleService, ZonedDateTime now, List<? extends String> templates) {
        if (templates.isEmpty()) {
            return buildCustomLines(scheduleService, now, MOTDConfig.CUSTOM_LINES.get());
        }

        // Check if template list changed
        if (lastRotationTemplates != templates) {
            lastRotationTemplates = templates;
            currentRotationIndex = 0;
            lastRotationTime = System.currentTimeMillis();
        }

        // Calculate time elapsed since last rotation
        long currentTime = System.currentTimeMillis();
        long rotationIntervalMillis = MOTDConfig.ROTATION_INTERVAL_SECONDS.get() * 1000L;
        long timeSinceLastRotation = currentTime - lastRotationTime;

        // Check if we should advance to next template
        if (timeSinceLastRotation >= rotationIntervalMillis) {
            // Move to next template
            currentRotationIndex = (currentRotationIndex + 1) % templates.size();
            lastRotationTime = currentTime;
        }

        String template = templates.get(currentRotationIndex);
        return MOTDFormatter.formatLine(scheduleService, now, template);
    }

    /**
     * Builds MOTD from custom line configuration.
     */
    private static Component buildCustomLines(ScheduleService scheduleService, ZonedDateTime now, List<? extends String> customLines) {
        MutableComponent result = Component.empty();
        
        for (int i = 0; i < customLines.size(); i++) {
            String line = customLines.get(i);
            Component formatted = MOTDFormatter.formatLine(scheduleService, now, line);
            result.append(formatted);
            
            if (i < customLines.size() - 1) {
                result.append(Component.literal("\n"));
            }
        }
        
        return result;
    }

    /**
     * Builds MOTD from custom format string.
     */
    private static Component buildCustomFormat(ScheduleService scheduleService, ZonedDateTime now, String format) {
        return MOTDFormatter.formatLine(scheduleService, now, format);
    }

    /**
     * Builds automatic MOTD based on configuration flags.
     */
    private static Component buildAutomatic(ScheduleService scheduleService, ZonedDateTime now) {
        List<Component> parts = new ArrayList<>();
        
        // Get schedule information
        boolean isOpen = scheduleService.isOpen(now);
        ForceMode forceMode = scheduleService.getForceMode();
        Optional<ZonedDateTime> nextClose = scheduleService.nextClose(now);
        FormattedSchedule nextOpen = ScheduleFormatter.formatNextOpen(scheduleService.nextOpen(now));
        
        // Show force mode if enabled
        if (MOTDConfig.SHOW_FORCE_MODE.get() && forceMode != ForceMode.NORMAL) {
            String forceModeText = forceMode == ForceMode.FORCE_OPEN 
                ? Messages.get("msg.motd_force_open")
                : Messages.get("msg.motd_force_closed");
            parts.add(MOTDFormatter.colorize(forceModeText, ChatFormatting.GOLD));
        }
        
        // Show status if enabled
        if (MOTDConfig.SHOW_STATUS.get()) {
            String statusKey = isOpen ? "msg.motd_status_open" : "msg.motd_status_closed";
            String statusText = Messages.get(statusKey);
            ChatFormatting statusColor = isOpen 
                ? MOTDColorParser.parseColor(MOTDConfig.OPEN_COLOR.get())
                : MOTDColorParser.parseColor(MOTDConfig.CLOSED_COLOR.get());
            parts.add(MOTDFormatter.colorize(statusText, statusColor));
        }
        
        // Show countdown if enabled and applicable
        if (MOTDConfig.SHOW_COUNTDOWN.get() && isOpen && nextClose.isPresent()) {
            addCountdownIfApplicable(parts, nextClose.get(), now);
        }
        
        // Show next close if enabled and open
        if (MOTDConfig.SHOW_NEXT_CLOSE.get() && isOpen && nextClose.isPresent()) {
            addNextClose(parts, nextClose.get());
        }
        
        // Show next open if enabled and closed
        if (MOTDConfig.SHOW_NEXT_OPEN.get() && !isOpen) {
            addNextOpen(parts, nextOpen);
        }
        
        // Combine parts
        if (parts.isEmpty()) {
            return Component.literal("");
        }
        
        return combineParts(parts);
    }

    private static void addCountdownIfApplicable(List<Component> parts, ZonedDateTime nextClose, ZonedDateTime now) {
        long minutesUntilClose = java.time.temporal.ChronoUnit.MINUTES.between(now, nextClose);
        int countdownThreshold = MOTDConfig.COUNTDOWN_THRESHOLD_MINUTES.get();
        
        if (countdownThreshold > 0 && minutesUntilClose <= countdownThreshold && minutesUntilClose > 0) {
            String countdownText = Messages.get("msg.motd_countdown")
                .replace("%minutes%", String.valueOf(minutesUntilClose));
            parts.add(MOTDFormatter.colorize(countdownText, ChatFormatting.YELLOW));
        }
    }

    private static void addNextClose(List<Component> parts, ZonedDateTime nextClose) {
        String closeTime = com.mrkayjaydee.playhours.core.TimeRange.formatTime(nextClose.toLocalTime(), Messages.getJavaLocale());
        String closeText = Messages.get("msg.motd_next_close")
            .replace("%closetime%", closeTime);
        ChatFormatting infoColor = MOTDColorParser.parseColor(MOTDConfig.INFO_COLOR.get());
        parts.add(MOTDFormatter.colorize(closeText, infoColor));
    }

    private static void addNextOpen(List<Component> parts, FormattedSchedule nextOpen) {
        String openText = Messages.get("msg.motd_next_open")
            .replace("%openday%", nextOpen.day)
            .replace("%opentime%", nextOpen.time);
        ChatFormatting infoColor = MOTDColorParser.parseColor(MOTDConfig.INFO_COLOR.get());
        parts.add(MOTDFormatter.colorize(openText, infoColor));
    }

    private static Component combineParts(List<Component> parts) {
        String separator = MOTDConfig.SEPARATOR.get();
        boolean useSecondLine = MOTDConfig.SHOW_ON_SECOND_LINE.get();
        
        MutableComponent result = Component.empty();
        
        if (useSecondLine) {
            // Put on second line
            result.append(Component.literal("\n"));
        }
        
        for (int i = 0; i < parts.size(); i++) {
            result.append(parts.get(i));
            if (i < parts.size() - 1) {
                result.append(Component.literal(separator));
            }
        }
        
        return result;
    }
}