/**
 * Copyright (C) 2022, 2024, 2025 Adrien Hopkins
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
package sevenUnitsGUI;

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.Optional;
import java.util.Set;

import sevenUnits.unit.UnitType;
import sevenUnits.utils.NameSymbol;
import sevenUnits.utils.Nameable;

/**
 * A class that simulates a View (supports both unit and expression conversion)
 * for testing. Getters and setters work as expected.
 * 
 * @author Adrien Hopkins
 * @since v0.4.0
 * @since 2022-01-29
 */
public final class ViewBot
		implements UnitConversionView, ExpressionConversionView {
	/**
	 * A record of the parameters given to
	 * {@link View#showPrefix(NameSymbol, String)}, for testing.
	 *
	 * @since 2022-04-16
	 */
	public static final class PrefixViewingRecord implements Nameable {
		private final NameSymbol nameSymbol;
		private final String multiplierString;

		/**
		 * @param nameSymbol
		 * @param multiplierString
		 * @since 2022-04-16
		 */
		public PrefixViewingRecord(NameSymbol nameSymbol,
				String multiplierString) {
			this.nameSymbol = nameSymbol;
			this.multiplierString = multiplierString;
		}

		@Override
		public boolean equals(Object obj) {
			if (this == obj)
				return true;
			if (!(obj instanceof PrefixViewingRecord))
				return false;
			final PrefixViewingRecord other = (PrefixViewingRecord) obj;
			return Objects.equals(this.multiplierString, other.multiplierString)
					&& Objects.equals(this.nameSymbol, other.nameSymbol);
		}

		@Override
		public NameSymbol getNameSymbol() {
			return this.nameSymbol;
		}

		@Override
		public int hashCode() {
			return Objects.hash(this.multiplierString, this.nameSymbol);
		}

		/** @return A string representation of the prefix multiplier. */
		public String multiplierString() {
			return this.multiplierString;
		}

		/** @return A {@code NameSymbol} describing the prefix. */
		public NameSymbol nameSymbol() {
			return this.nameSymbol;
		}

		@Override
		public String toString() {
			final StringBuilder builder = new StringBuilder();
			builder.append("PrefixViewingRecord [nameSymbol=");
			builder.append(this.nameSymbol);
			builder.append(", multiplierString=");
			builder.append(this.multiplierString);
			builder.append("]");
			return builder.toString();
		}
	}

	/**
	 * A record of the parameters given to
	 * {@link View#showUnit(NameSymbol, String, String, UnitType)}, for testing.
	 *
	 * @since 2022-04-16
	 */
	public static final class UnitViewingRecord implements Nameable {
		private final NameSymbol nameSymbol;
		private final String definition;
		private final String dimensionName;
		private final UnitType unitType;

		/**
		 * @param nameSymbol    name(s) and symbol of unit
		 * @param definition    unit's definition string
		 * @param dimensionName name of unit's dimension
		 * @param unitType      type of unit (metric/semi-metric/non-metric)
		 * @since 2022-04-16
		 */
		public UnitViewingRecord(NameSymbol nameSymbol, String definition,
				String dimensionName, UnitType unitType) {
			this.nameSymbol = nameSymbol;
			this.definition = definition;
			this.dimensionName = dimensionName;
			this.unitType = unitType;
		}

		/**
		 * @return the definition
		 * @since 2022-04-16
		 */
		public String definition() {
			return this.definition;
		}

		/**
		 * @return the dimensionName
		 * @since 2022-04-16
		 */
		public String dimensionName() {
			return this.dimensionName;
		}

		@Override
		public boolean equals(Object obj) {
			if (this == obj)
				return true;
			if (!(obj instanceof UnitViewingRecord))
				return false;
			final UnitViewingRecord other = (UnitViewingRecord) obj;
			return Objects.equals(this.definition, other.definition)
					&& Objects.equals(this.dimensionName, other.dimensionName)
					&& Objects.equals(this.nameSymbol, other.nameSymbol)
					&& this.unitType == other.unitType;
		}

		/**
		 * @return the nameSymbol
		 * @since 2022-04-16
		 */
		@Override
		public NameSymbol getNameSymbol() {
			return this.nameSymbol;
		}

		@Override
		public int hashCode() {
			return Objects.hash(this.definition, this.dimensionName,
					this.nameSymbol, this.unitType);
		}

		/** @return name(s) and symbol of unit */
		public NameSymbol nameSymbol() {
			return this.nameSymbol;
		}

		@Override
		public String toString() {
			final StringBuilder builder = new StringBuilder();
			builder.append("UnitViewingRecord [nameSymbol=");
			builder.append(this.nameSymbol);
			builder.append(", definition=");
			builder.append(this.definition);
			builder.append(", dimensionName=");
			builder.append(this.dimensionName);
			builder.append(", unitType=");
			builder.append(this.unitType);
			builder.append("]");
			return builder.toString();
		}

		/**
		 * @return the unitType
		 * @since 2022-04-16
		 */
		public UnitType unitType() {
			return this.unitType;
		}
	}

	/** The presenter that works with this ViewBot */
	private final Presenter presenter;

	/** The dimensions available to select from */
	private Set<String> dimensionNames = Set.of();
	/** The expression in the From field */
	private String fromExpression = "";
	/** The expression in the To field */
	private String toExpression = "";
	/**
	 * The user-provided string representing the value in {@code fromSelection}
	 */
	private String inputValue = "";
	/** The unit selected in the From selection */
	private Optional<String> fromSelection = Optional.empty();
	/** The unit selected in the To selection */
	private Optional<String> toSelection = Optional.empty();
	/** The currently selected dimension */
	private Optional<String> selectedDimensionName = Optional.empty();
	/** The units available in the From selection */
	private Set<String> fromUnits = Set.of();
	/** The units available in the To selection */
	private Set<String> toUnits = Set.of();

	/** The selected unit in the unit viewer */
	private Optional<String> unitViewerSelection = Optional.empty();
	/** The selected unit in the prefix viewer */
	private Optional<String> prefixViewerSelection = Optional.empty();

	/** Saved outputs of all unit conversions */
	private final List<UnitConversionRecord> unitConversions;
	/** Saved outputs of all unit expressions */
	private final List<UnitConversionRecord> expressionConversions;
	/** Saved outputs of all unit viewings */
	private final List<UnitViewingRecord> unitViewingRecords;
	/** Saved outputs of all prefix viewings */
	private final List<PrefixViewingRecord> prefixViewingRecords;

	/**
	 * Creates a new {@code ViewBot} with a new presenter.
	 *
	 * @since 2022-01-29
	 */
	public ViewBot() {
		this.presenter = new Presenter(this);

		this.unitConversions = new ArrayList<>();
		this.expressionConversions = new ArrayList<>();
		this.unitViewingRecords = new ArrayList<>();
		this.prefixViewingRecords = new ArrayList<>();
	}

	/**
	 * @return list of records of expression conversions done by this bot
	 * @since 2022-04-09
	 */
	public List<UnitConversionRecord> expressionConversionList() {
		return Collections.unmodifiableList(this.expressionConversions);
	}

	/**
	 * @return the available dimensions
	 * @since 2022-01-29
	 */
	@Override
	public Set<String> getDimensionNames() {
		return this.dimensionNames;
	}

	@Override
	public String getFromExpression() {
		return this.fromExpression;
	}

	@Override
	public Optional<String> getFromSelection() {
		return this.fromSelection;
	}

	/**
	 * @return the units available for selection in From
	 * @since 2022-01-29
	 */
	@Override
	public Set<String> getFromUnitNames() {
		return Collections.unmodifiableSet(this.fromUnits);
	}

	@Override
	public String getInputValue() {
		return this.inputValue;
	}

	/**
	 * @return the presenter associated with tihs view
	 * @since 2022-01-29
	 */
	@Override
	public Presenter getPresenter() {
		return this.presenter;
	}

	@Override
	public Optional<String> getSelectedDimensionName() {
		return this.selectedDimensionName;
	}

	@Override
	public String getToExpression() {
		return this.toExpression;
	}

	@Override
	public Optional<String> getToSelection() {
		return this.toSelection;
	}

	/**
	 * @return the units available for selection in To
	 * @since 2022-01-29
	 */
	@Override
	public Set<String> getToUnitNames() {
		return Collections.unmodifiableSet(this.toUnits);
	}

	@Override
	public Optional<String> getViewedPrefixName() {
		return this.prefixViewerSelection;
	}

	@Override
	public Optional<String> getViewedUnitName() {
		return this.unitViewerSelection;
	}

	/**
	 * @return list of records of this viewBot's prefix views
	 * @since 2022-04-16
	 */
	public List<PrefixViewingRecord> prefixViewList() {
		return Collections.unmodifiableList(this.prefixViewingRecords);
	}

	@Override
	public void setDimensionNames(Set<String> dimensionNames) {
		this.dimensionNames = Objects.requireNonNull(dimensionNames,
				"dimensions may not be null");
	}

	/**
	 * Sets the From expression (as in {@link #getFromExpression}).
	 *
	 * @param fromExpression the expression to convert from
	 * @throws NullPointerException if {@code fromExpression} is null
	 * @since 2022-01-29
	 */
	public void setFromExpression(String fromExpression) {
		this.fromExpression = Objects.requireNonNull(fromExpression,
				"fromExpression cannot be null.");
	}

	/**
	 * @param fromSelection the fromSelection to set
	 * @since 2022-01-29
	 */
	public void setFromSelection(Optional<String> fromSelection) {
		this.fromSelection = Objects.requireNonNull(fromSelection,
				"fromSelection cannot be null");
	}

	/**
	 * @param fromSelection the fromSelection to set
	 * @since 2022-02-10
	 */
	public void setFromSelection(String fromSelection) {
		this.setFromSelection(Optional.of(fromSelection));
	}

	@Override
	public void setFromUnitNames(Set<String> units) {
		this.fromUnits = Objects.requireNonNull(units, "units may not be null");
	}

	/**
	 * @param inputValue the inputValue to set
	 * @since 2022-01-29
	 */
	public void setInputValue(String inputValue) {
		this.inputValue = inputValue;
	}

	/**
	 * @param selectedDimensionName the selectedDimensionName to set
	 * @since 2022-01-29
	 */
	public void setSelectedDimensionName(
			Optional<String> selectedDimensionName) {
		this.selectedDimensionName = selectedDimensionName;
	}

	/**
	 * Sets the view's selected dimension
	 * @param selectedDimensionName name of dimension to select (string)
	 */
	public void setSelectedDimensionName(String selectedDimensionName) {
		this.setSelectedDimensionName(Optional.of(selectedDimensionName));
	}

	/**
	 * Sets the To expression (as in {@link #getToExpression}).
	 *
	 * @param toExpression the expression to convert to
	 * @throws NullPointerException if {@code toExpression} is null
	 * @since 2022-01-29
	 */
	public void setToExpression(String toExpression) {
		this.toExpression = Objects.requireNonNull(toExpression,
				"toExpression cannot be null.");
	}

	/**
	 * @param toSelection unit set in the 'To' selection
	 * @since 2022-01-29
	 */
	public void setToSelection(Optional<String> toSelection) {
		this.toSelection = Objects.requireNonNull(toSelection,
				"toSelection cannot be null.");
	}

	/**
	 * @param toSelection unit set in the 'To' selection
	 */
	public void setToSelection(String toSelection) {
		this.setToSelection(Optional.of(toSelection));
	}

	@Override
	public void setToUnitNames(Set<String> units) {
		this.toUnits = Objects.requireNonNull(units, "units may not be null");
	}

	@Override
	public void setViewablePrefixNames(Set<String> prefixNames) {
		// do nothing, ViewBot supports selecting any prefix
	}

	@Override
	public void setViewableUnitNames(Set<String> unitNames) {
		// do nothing, ViewBot supports selecting any unit
	}

	/**
	 * @param viewedPrefixName name of prefix being used
	 */
	public void setViewedPrefixName(Optional<String> viewedPrefixName) {
		this.prefixViewerSelection = viewedPrefixName;
	}

	/**
	 * @param viewedPrefixName name of prefix being used (may not be null)
	 * @throws NullPointerException if {@code viewedPrefixName} is null
	 */
	public void setViewedPrefixName(String viewedPrefixName) {
		this.setViewedPrefixName(Optional.of(viewedPrefixName));
	}

	/**
	 * @param viewedUnitName name of unit being used
	 */
	public void setViewedUnitName(Optional<String> viewedUnitName) {
		this.unitViewerSelection = viewedUnitName;
	}

	/**
	 * @param viewedUnitName name of unit being used (may not be null)
	 * @throws NullPointerException if {@code viewedUnitName} is null
	 */
	public void setViewedUnitName(String viewedUnitName) {
		this.setViewedUnitName(Optional.of(viewedUnitName));
	}

	@Override
	public void showErrorMessage(String title, String message) {
		System.err.printf("%s: %s%n", title, message);
	}

	@Override
	public void showExpressionConversionOutput(UnitConversionRecord uc) {
		this.expressionConversions.add(uc);
		System.out.println("Expression Conversion: " + uc);
	}

	@Override
	public void showPrefix(NameSymbol name, String multiplierString) {
		this.prefixViewingRecords
				.add(new PrefixViewingRecord(name, multiplierString));
	}

	@Override
	public void showUnit(NameSymbol name, String definition,
			String dimensionName, UnitType type) {
		this.unitViewingRecords
				.add(new UnitViewingRecord(name, definition, dimensionName, type));
	}

	@Override
	public void showUnitConversionOutput(UnitConversionRecord uc) {
		this.unitConversions.add(uc);
		System.out.println("Unit Conversion: " + uc);
	}

	@Override
	public String toString() {
		return super.toString() + String.format("[presenter=%s]", this.presenter);
	}

	/**
	 * @return list of records of every unit conversion made by this bot
	 * @since 2022-04-09
	 */
	public List<UnitConversionRecord> unitConversionList() {
		return Collections.unmodifiableList(this.unitConversions);
	}

	/**
	 * @return list of records of unit viewings made by this bot
	 * @since 2022-04-16
	 */
	public List<UnitViewingRecord> unitViewList() {
		return Collections.unmodifiableList(this.unitViewingRecords);
	}

	@Override
	public void updateText() {
		// do nothing, since ViewBot is not localized
	}
}