package io.dropwizard.metrics;

import com.codahale.metrics.MetricAttribute;
import com.codahale.metrics.MetricFilter;
import com.codahale.metrics.ScheduledReporter;
import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import io.dropwizard.util.Duration;
import io.dropwizard.validation.MinDuration;
import org.hibernate.validator.valuehandling.UnwrapValidatedValue;

import javax.validation.Valid;
import javax.validation.constraints.NotNull;
import java.util.EnumSet;
import java.util.Optional;
import java.util.Set;
import java.util.concurrent.TimeUnit;

A base ReporterFactory for configuring metric reporters. 
 Configures options common to all ScheduledReporters. 

Configuration Parameters:

    

        
Name
        
Default
        
Description
    
    

        
durationUnit
        
milliseconds
        
The unit to report durations as. Overrides per-metric duration units.
    
    

        
rateUnit
        
seconds
        
The unit to report rates as. Overrides per-metric rate units.
    
    

        
excludes
        
No excluded metrics.
        
Metrics to exclude from reports, by name. When defined, matching metrics will not be reported. See getFilter().
    
    

        
includes
        
All metrics included.
        
Metrics to include in reports, by name. When defined, only these metrics will be reported. See getFilter(). Exclusion rules (excludes) take precedence, so if a name matches both excludes and includes, it is excluded.
    
    

        
excludesAttributes
        
No excluded attributes.
        
Metric attributes to exclude from reports, by name (e.g `p98`, `m15_rate`, `stddev`). When defined, matching metrics attributes will not be reported. See MetricAttribute
    
    

        
includesAttributes
        
All metrics attributes.
        
Metrics attributes to include in reports, by name (e.g `p98`, `m15_rate`, `stddev`). When defined, only these attributes will be reported. See MetricAttribute. Exclusion rules (excludes) take precedence, so if an attribute matches both includesAttributes
        and excludesAttributes, it is excluded.
    
    

        
useRegexFilters
        
false
        
Indicates whether the values of the 'includes' and 'excludes' fields should be
        treated as regular expressions or not.
    
    

        
frequency
        
none
        
The frequency to report metrics. Overrides the default.
    

/**
 * A base {@link ReporterFactory} for configuring metric reporters.
 * <p/>
 * Configures options common to all {@link ScheduledReporter}s.
 * <p/>
 * <b>Configuration Parameters:</b>
 * <table>
 *     <tr>
 *         <td>Name</td>
 *         <td>Default</td>
 *         <td>Description</td>
 *     </tr>
 *     <tr>
 *         <td>durationUnit</td>
 *         <td>milliseconds</td>
 *         <td>The unit to report durations as. Overrides per-metric duration units.</td>
 *     </tr>
 *     <tr>
 *         <td>rateUnit</td>
 *         <td>seconds</td>
 *         <td>The unit to report rates as. Overrides per-metric rate units.</td>
 *     </tr>
 *     <tr>
 *         <td>excludes</td>
 *         <td>No excluded metrics.</td>
 *         <td>Metrics to exclude from reports, by name. When defined, matching metrics will not be
 *         reported. See {@link #getFilter()}.</td>
 *     </tr>
 *     <tr>
 *         <td>includes</td>
 *         <td>All metrics included.</td>
 *         <td>Metrics to include in reports, by name. When defined, only these metrics will be
 *         reported. See {@link #getFilter()}.  Exclusion rules (excludes) take precedence,
 *         so if a name matches both <i>excludes</i> and <i>includes</i>, it is excluded.</td>
 *     </tr>
 *     <tr>
 *         <td>excludesAttributes</td>
 *         <td>No excluded attributes.</td>
 *         <td>Metric attributes to exclude from reports, by name (e.g `p98`, `m15_rate`, `stddev`).
 *         When defined, matching metrics attributes will not be reported. See {@link MetricAttribute}</td>
 *     </tr>
 *     <tr>
 *         <td>includesAttributes</td>
 *         <td>All metrics attributes.</td>
 *         <td>Metrics attributes to include in reports, by name (e.g `p98`, `m15_rate`, `stddev`).
 *         When defined, only these attributes will be reported. See {@link MetricAttribute}.
 *         Exclusion rules (excludes) take precedence, so if an attribute matches both <i>includesAttributes</i>
 *         and <i>excludesAttributes</i>, it is excluded.</td>
 *     </tr>
 *     <tr>
 *         <td>useRegexFilters</td>
 *         <td>false</td>
 *         <td>Indicates whether the values of the 'includes' and 'excludes' fields should be
 *         treated as regular expressions or not.</td>
 *     </tr>
 *     <tr>
 *         <td>frequency</td>
 *         <td>none</td>
 *         <td>The frequency to report metrics. Overrides the {@link
 *         MetricsFactory#getFrequency() default}.</td>
 *     </tr>
 * </table>
 */
public abstract class BaseReporterFactory implements ReporterFactory {

    private static final DefaultStringMatchingStrategy DEFAULT_STRING_MATCHING_STRATEGY =
            new DefaultStringMatchingStrategy();

    private static final RegexStringMatchingStrategy REGEX_STRING_MATCHING_STRATEGY =
            new RegexStringMatchingStrategy();

    private static final SubstringMatchingStrategy SUBSTRING_MATCHING_STRATEGY =
        new SubstringMatchingStrategy();

    @NotNull
    private TimeUnit durationUnit = TimeUnit.MILLISECONDS;

    @NotNull
    private TimeUnit rateUnit = TimeUnit.SECONDS;

    @NotNull
    private ImmutableSet<String> excludes = ImmutableSet.of();

    @NotNull
    private ImmutableSet<String> includes = ImmutableSet.of();

    @Valid
    @MinDuration(0)
    @UnwrapValidatedValue
    private Optional<Duration> frequency = Optional.empty();

    private boolean useRegexFilters = false;

    private boolean useSubstringMatching = false;

    private EnumSet<MetricAttribute> excludesAttributes = EnumSet.noneOf(MetricAttribute.class);

    private EnumSet<MetricAttribute> includesAttributes = EnumSet.allOf(MetricAttribute.class);

    public TimeUnit getDurationUnit() {
        return durationUnit;
    }

    @JsonProperty
    public void setDurationUnit(TimeUnit durationUnit) {
        this.durationUnit = durationUnit;
    }

    @JsonProperty
    public TimeUnit getRateUnit() {
        return rateUnit;
    }

    @JsonProperty
    public void setRateUnit(final TimeUnit rateUnit) {
        this.rateUnit = rateUnit;
    }

    @JsonProperty
    public ImmutableSet<String> getIncludes() {
        return includes;
    }

    @JsonProperty
    public void setIncludes(ImmutableSet<String> includes) {
        this.includes = includes;
    }

    @JsonProperty
    public ImmutableSet<String> getExcludes() {
        return excludes;
    }

    @JsonProperty
    public void setExcludes(ImmutableSet<String> excludes) {
        this.excludes = excludes;
    }

    @Override
    @JsonProperty
    public Optional<Duration> getFrequency() {
        return frequency;
    }

    @JsonProperty
    public void setFrequency(Optional<Duration> frequency) {
        this.frequency = frequency;
    }

    @JsonProperty
    public boolean getUseRegexFilters() {
        return useRegexFilters;
    }

    @JsonProperty
    public void setUseRegexFilters(boolean useRegexFilters) {
        this.useRegexFilters = useRegexFilters;
    }

    @JsonProperty
    public boolean getUseSubstringMatching() {
        return useSubstringMatching;
    }

    @JsonProperty
    public void setUseSubstringMatching(boolean useSubstringMatching) {
        this.useSubstringMatching = useSubstringMatching;
    }

    @JsonProperty
    public EnumSet<MetricAttribute> getExcludesAttributes() {
        return excludesAttributes;
    }

    @JsonProperty
    public void setExcludesAttributes(EnumSet<MetricAttribute> excludesAttributes) {
        this.excludesAttributes = excludesAttributes;
    }

    @JsonProperty
    public EnumSet<MetricAttribute> getIncludesAttributes() {
        return includesAttributes;
    }

    @JsonProperty
    public void setIncludesAttributes(EnumSet<MetricAttribute> includesAttributes) {
        this.includesAttributes = includesAttributes;
    }

    
Gets a MetricFilter that specifically includes and excludes configured metrics. 

Filtering works in 4 ways:

    
unfiltered
    
All metrics are reported
    
excludes-only
    
All metrics are reported, except those whose name is listed in excludes.
    
includes-only
    
Only metrics whose name is listed in includes are reported.
    
mixed (both includes and excludes
    
Only metrics whose name is listed in includes and
    not listed in excludes are reported;
    excludes takes precedence over includes.

See Also:
getIncludes()
getExcludes()
Returns:
the filter for selecting metrics based on the configured excludes/includes./**
     * Gets a {@link MetricFilter} that specifically includes and excludes configured metrics.
     * <p/>
     * Filtering works in 4 ways:
     * <dl>
     *     <dt><i>unfiltered</i></dt>
     *     <dd>All metrics are reported</dd>
     *     <dt><i>excludes</i>-only</dt>
     *     <dd>All metrics are reported, except those whose name is listed in <i>excludes</i>.</dd>
     *     <dt><i>includes</i>-only</dt>
     *     <dd>Only metrics whose name is listed in <i>includes</i> are reported.</dd>
     *     <dt>mixed (both <i>includes</i> and <i>excludes</i></dt>
     *     <dd>Only metrics whose name is listed in <i>includes</i> and
     *     <em>not</em> listed in <i>excludes</i> are reported;
     *     <i>excludes</i> takes precedence over <i>includes</i>.</dd>
     * </dl>
     *
     * @return the filter for selecting metrics based on the configured excludes/includes.
     * @see #getIncludes()
     * @see #getExcludes()
     */
    @JsonIgnore
    public MetricFilter getFilter() {
        final StringMatchingStrategy stringMatchingStrategy = getUseRegexFilters() ?
                REGEX_STRING_MATCHING_STRATEGY : (getUseSubstringMatching() ? SUBSTRING_MATCHING_STRATEGY : DEFAULT_STRING_MATCHING_STRATEGY);

        return (name, metric) -> {
            // Include the metric if its name is not excluded and its name is included
            // Where, by default, with no includes setting, all names are included.
            return !stringMatchingStrategy.containsMatch(getExcludes(), name) &&
                    (getIncludes().isEmpty() || stringMatchingStrategy.containsMatch(getIncludes(), name));
        };
    }

    protected Set<MetricAttribute> getDisabledAttributes() {
        return ImmutableSet.copyOf(Sets.union(
            Sets.difference(EnumSet.allOf(MetricAttribute.class), getIncludesAttributes()),
            getExcludesAttributes()));
    }
}