// Calendar configuration management

import { eventBus } from './EventBus';
import { EventTypes } from '../constants/EventTypes';
import { CalendarConfig as ICalendarConfig, ViewPeriod, CalendarMode, DateViewType, CalendarType } from '../types/CalendarTypes';

/**
 * Layout and timing settings for the calendar grid
 */
interface GridSettings {
  // Time boundaries
  dayStartHour: number;
  dayEndHour: number;
  workStartHour: number;
  workEndHour: number;
  
  // Layout settings
  hourHeight: number;
  snapInterval: number;
  fitToWidth: boolean;
  scrollToHour: number | null;
  
  // Display options
  showCurrentTime: boolean;
  showWorkHours: boolean;
}

/**
 * View settings for date-based calendar mode
 */
interface DateViewSettings {
  period: ViewPeriod;  // day/week/month
  weekDays: number;    // Number of days to show in week view
  firstDayOfWeek: number; // 0=Sunday, 1=Monday
  showAllDay: boolean; // Show all-day event row
}

/**
 * Work week configuration settings
 */
interface WorkWeekSettings {
  id: string;
  workDays: number[];    // [1,2,3,4,5] for mon-fri
  dayNames: string[];    // ['Mon','Tue','Wed','Thu','Fri'] 
  totalDays: number;     // 5
  firstWorkDay: number;  // 1 = Monday
}

/**
 * View settings for resource-based calendar mode
 */
interface ResourceViewSettings {
  maxResources: number;         // Maximum resources to display
  showAvatars: boolean;         // Display user avatars
  avatarSize: number;           // Avatar size in pixels
  resourceNameFormat: 'full' | 'short'; // How to display names
  showResourceDetails: boolean; // Show additional resource info
  showAllDay: boolean;          // Show all-day event row
}

/**
 * Calendar configuration management
 */
export class CalendarConfig {
  private config: ICalendarConfig;
  private calendarMode: CalendarMode = 'date';
  private selectedDate: Date | null = null;
  private gridSettings: GridSettings;
  private dateViewSettings: DateViewSettings;
  private resourceViewSettings: ResourceViewSettings;
  private currentWorkWeek: string = 'standard';

  constructor() {
    this.config = {
      // Scrollbar styling
      scrollbarWidth: 16,     // Width of scrollbar in pixels
      scrollbarColor: '#666', // Scrollbar thumb color
      scrollbarTrackColor: '#f0f0f0', // Scrollbar track color
      scrollbarHoverColor: '#b53f7aff', // Scrollbar thumb hover color
      scrollbarBorderRadius: 6, // Border radius for scrollbar thumb
      
      // Interaction settings
      allowDrag: true,
      allowResize: true,
      allowCreate: true,
      
      // API settings
      apiEndpoint: '/api/events',
      dateFormat: 'YYYY-MM-DD',
      timeFormat: 'HH:mm',
      
      // Feature flags
      enableSearch: true,
      enableTouch: true,
      
      // Event defaults
      defaultEventDuration: 60, // Minutes
      minEventDuration: 15,     // Will be same as snapInterval
      maxEventDuration: 480     // 8 hours
    };

    // Grid display settings
    this.gridSettings = {
      hourHeight: 60,
      dayStartHour: 0,
      dayEndHour: 24,
      workStartHour: 8,
      workEndHour: 17,
      snapInterval: 15,
      showCurrentTime: true,
      showWorkHours: true,
      fitToWidth: false,
      scrollToHour: 8
    };

    // Date view settings
    this.dateViewSettings = {
      period: 'week',
      weekDays: 7,
      firstDayOfWeek: 1,
      showAllDay: true
    };

    // Resource view settings
    this.resourceViewSettings = {
      maxResources: 10,
      showAvatars: true,
      avatarSize: 32,
      resourceNameFormat: 'full',
      showResourceDetails: true,
      showAllDay: true
    };

    // Set computed values
    this.config.minEventDuration = this.gridSettings.snapInterval;
    
    // Load calendar type from URL parameter
    this.loadCalendarType();
    
    // Load from data attributes
    this.loadFromDOM();
  }

  /**
   * Load calendar type and date from URL parameters
   */
  private loadCalendarType(): void {
    const urlParams = new URLSearchParams(window.location.search);
    const typeParam = urlParams.get('type');
    const dateParam = urlParams.get('date');
    
    // Set calendar mode
    if (typeParam === 'resource' || typeParam === 'date') {
      this.calendarMode = typeParam;
      console.log(`CalendarConfig: Calendar mode set to '${this.calendarMode}' from URL parameter`);
    } else {
      this.calendarMode = 'date'; // Default
      console.log(`CalendarConfig: Calendar mode defaulted to '${this.calendarMode}'`);
    }
    
    // Set selected date
    if (dateParam) {
      const parsedDate = new Date(dateParam);
      if (!isNaN(parsedDate.getTime())) {
        this.selectedDate = parsedDate;
        console.log(`CalendarConfig: Selected date set to '${this.selectedDate.toISOString()}' from URL parameter`);
      } else {
        console.warn(`CalendarConfig: Invalid date parameter '${dateParam}', using current date`);
        this.selectedDate = new Date();
      }
    } else {
      this.selectedDate = new Date(); // Default to today
      console.log(`CalendarConfig: Selected date defaulted to today: ${this.selectedDate.toISOString()}`);
    }
  }

  /**
   * Load configuration from DOM data attributes
   */
  private loadFromDOM(): void {
    const calendar = document.querySelector('swp-calendar') as HTMLElement;
    if (!calendar) return;

    // Read data attributes
    const attrs = calendar.dataset;
    
    // Update date view settings
    if (attrs.view) this.dateViewSettings.period = attrs.view as ViewPeriod;
    if (attrs.weekDays) this.dateViewSettings.weekDays = parseInt(attrs.weekDays);
    
    // Update grid settings
    if (attrs.snapInterval) this.gridSettings.snapInterval = parseInt(attrs.snapInterval);
    if (attrs.dayStartHour) this.gridSettings.dayStartHour = parseInt(attrs.dayStartHour);
    if (attrs.dayEndHour) this.gridSettings.dayEndHour = parseInt(attrs.dayEndHour);
    if (attrs.hourHeight) this.gridSettings.hourHeight = parseInt(attrs.hourHeight);
    if (attrs.fitToWidth !== undefined) this.gridSettings.fitToWidth = attrs.fitToWidth === 'true';
    
    // Update computed values
    this.config.minEventDuration = this.gridSettings.snapInterval;
  }

  /**
   * Get a config value
   */
  get<K extends keyof ICalendarConfig>(key: K): ICalendarConfig[K] {
    return this.config[key];
  }

  /**
   * Set a config value
   */
  set<K extends keyof ICalendarConfig>(key: K, value: ICalendarConfig[K]): void {
    const oldValue = this.config[key];
    this.config[key] = value;

    // Update computed values handled in specific update methods

    // Emit config update event
    eventBus.emit(EventTypes.CONFIG_UPDATE, {
      key,
      value,
      oldValue
    });
  }

  /**
   * Update multiple config values
   */
  update(updates: Partial<ICalendarConfig>): void {
    Object.entries(updates).forEach(([key, value]) => {
      this.set(key as keyof ICalendarConfig, value);
    });
  }

  /**
   * Get all config
   */
  getAll(): ICalendarConfig {
    return { ...this.config };
  }

  /**
   * Calculate derived values
   */
  
  get minuteHeight(): number {
    return this.gridSettings.hourHeight / 60;
  }

  get totalHours(): number {
    return this.gridSettings.dayEndHour - this.gridSettings.dayStartHour;
  }

  get totalMinutes(): number {
    return this.totalHours * 60;
  }

  get slotsPerHour(): number {
    return 60 / this.gridSettings.snapInterval;
  }

  get totalSlots(): number {
    return this.totalHours * this.slotsPerHour;
  }

  get slotHeight(): number {
    return this.gridSettings.hourHeight / this.slotsPerHour;
  }

  /**
   * Validate snap interval
   */
  isValidSnapInterval(interval: number): boolean {
    return [5, 10, 15, 30, 60].includes(interval);
  }

  /**
   * Get grid display settings
   */
  getGridSettings(): GridSettings {
    return { ...this.gridSettings };
  }

  /**
   * Update grid display settings
   */
  updateGridSettings(updates: Partial<GridSettings>): void {
    this.gridSettings = { ...this.gridSettings, ...updates };
    
    // Update computed values
    if (updates.snapInterval) {
      this.config.minEventDuration = updates.snapInterval;
    }
    
    // Emit grid settings update event
    eventBus.emit(EventTypes.CONFIG_UPDATE, {
      key: 'gridSettings',
      value: this.gridSettings,
      oldValue: this.gridSettings
    });
  }

  /**
   * Get date view settings
   */
  getDateViewSettings(): DateViewSettings {
    return { ...this.dateViewSettings };
  }
  
  /**
   * Legacy method - for backwards compatibility
   */
  getDateHeaderSettings(): DateViewSettings {
    return this.getDateViewSettings();
  }

  /**
   * Update date view settings
   */
  updateDateViewSettings(updates: Partial<DateViewSettings>): void {
    this.dateViewSettings = { ...this.dateViewSettings, ...updates };
    
    // Emit date view settings update event
    eventBus.emit(EventTypes.CONFIG_UPDATE, {
      key: 'dateViewSettings',
      value: this.dateViewSettings,
      oldValue: this.dateViewSettings
    });
  }
  
  /**
   * Legacy method - for backwards compatibility
   */
  updateDateHeaderSettings(updates: Partial<DateViewSettings>): void {
    this.updateDateViewSettings(updates);
  }

  /**
   * Get resource view settings
   */
  getResourceViewSettings(): ResourceViewSettings {
    return { ...this.resourceViewSettings };
  }
  
  /**
   * Legacy method - for backwards compatibility
   */
  getResourceHeaderSettings(): ResourceViewSettings {
    return this.getResourceViewSettings();
  }

  /**
   * Update resource view settings
   */
  updateResourceViewSettings(updates: Partial<ResourceViewSettings>): void {
    this.resourceViewSettings = { ...this.resourceViewSettings, ...updates };
    
    // Emit resource view settings update event
    eventBus.emit(EventTypes.CONFIG_UPDATE, {
      key: 'resourceViewSettings',
      value: this.resourceViewSettings,
      oldValue: this.resourceViewSettings
    });
  }
  
  /**
   * Legacy method - for backwards compatibility
   */
  updateResourceHeaderSettings(updates: Partial<ResourceViewSettings>): void {
    this.updateResourceViewSettings(updates);
  }

  /**
   * Check if current mode is resource-based
   */
  isResourceMode(): boolean {
    return this.calendarMode === 'resource';
  }

  /**
   * Check if current mode is date-based
   */
  isDateMode(): boolean {
    return this.calendarMode === 'date';
  }
  
  /**
   * Legacy methods - for backwards compatibility
   */
  isResourceView(): boolean {
    return this.isResourceMode();
  }
  
  isDateView(): boolean {
    return this.isDateMode();
  }

  /**
   * Get calendar mode
   */
  getCalendarMode(): CalendarMode {
    return this.calendarMode;
  }

  /**
   * Set calendar mode
   */
  setCalendarMode(mode: CalendarMode): void {
    const oldMode = this.calendarMode;
    this.calendarMode = mode;
    
    // Emit calendar mode change event
    eventBus.emit(EventTypes.CALENDAR_TYPE_CHANGED, {
      oldType: oldMode,
      newType: mode
    });
  }

  /**
   * Get selected date
   */
  getSelectedDate(): Date | null {
    return this.selectedDate;
  }

  /**
   * Set selected date
   */
  setSelectedDate(date: Date): void {
    this.selectedDate = date;
    
    // Emit date change event
    eventBus.emit(EventTypes.SELECTED_DATE_CHANGED, {
      date: date
    });
  }

  /**
   * Get work week presets
   */
  private getWorkWeekPresets(): { [key: string]: WorkWeekSettings } {
    return {
      'standard': { 
        id: 'standard',
        workDays: [1,2,3,4,5], 
        dayNames: ['Mon','Tue','Wed','Thu','Fri'], 
        totalDays: 5,
        firstWorkDay: 1
      },
      'compressed': { 
        id: 'compressed',
        workDays: [1,2,3,4], 
        dayNames: ['Mon','Tue','Wed','Thu'], 
        totalDays: 4,
        firstWorkDay: 1
      },
      'midweek': { 
        id: 'midweek',
        workDays: [3,4,5], 
        dayNames: ['Wed','Thu','Fri'], 
        totalDays: 3,
        firstWorkDay: 3
      },
      'weekend': { 
        id: 'weekend',
        workDays: [6,0], 
        dayNames: ['Sat','Sun'], 
        totalDays: 2,
        firstWorkDay: 6
      },
      'fullweek': { 
        id: 'fullweek',
        workDays: [0,1,2,3,4,5,6], 
        dayNames: ['Sun','Mon','Tue','Wed','Thu','Fri','Sat'], 
        totalDays: 7,
        firstWorkDay: 0
      }
    };
  }

  /**
   * Get current work week settings
   */
  getWorkWeekSettings(): WorkWeekSettings {
    const presets = this.getWorkWeekPresets();
    return presets[this.currentWorkWeek] || presets['standard'];
  }

  /**
   * Set work week preset
   */
  setWorkWeek(workWeekId: string): void {
    const presets = this.getWorkWeekPresets();
    if (presets[workWeekId]) {
      this.currentWorkWeek = workWeekId;
      
      // Update dateViewSettings to match work week
      this.dateViewSettings.weekDays = presets[workWeekId].totalDays;
      
      // Emit work week change event
      eventBus.emit(EventTypes.WORKWEEK_CHANGED, {
        workWeekId: workWeekId,
        settings: presets[workWeekId]
      });
    }
  }

  /**
   * Get current work week ID
   */
  getCurrentWorkWeek(): string {
    return this.currentWorkWeek;
  }
}

// Create singleton instance
export const calendarConfig = new CalendarConfig();