package org.unix4j.unix.uniq;

import java.util.List;
import java.util.Map;
import java.util.Arrays;

import org.unix4j.command.Arguments;
import org.unix4j.context.ExecutionContext;
import org.unix4j.convert.ValueConverter;
import org.unix4j.option.DefaultOptionSet;
import org.unix4j.util.ArgsUtil;
import org.unix4j.util.ArrayUtil;
import org.unix4j.variable.Arg;
import org.unix4j.variable.VariableContext;

import org.unix4j.unix.Uniq;

/**
 * Arguments and options for the {@link Uniq uniq} command.
 */
public final class UniqArguments implements Arguments<UniqArguments> {
        
        private final UniqOptions options;

        
        // operand: <file>
        private java.io.File file;
        private boolean fileIsSet = false;
        
        // operand: <path>
        private String path;
        private boolean pathIsSet = false;
        
        // operand: <args>
        private String[] args;
        private boolean argsIsSet = false;
        
        /**
         * Constructor to use if no options are specified.
         */
        public UniqArguments() {
                this.options = UniqOptions.EMPTY;
        }

        /**
         * Constructor with option set containing the selected command options.
         * 
         * @param options the selected options
         * @throws NullPointerException if the argument is null
         */
        public UniqArguments(UniqOptions options) {
                if (options == null) {
                        throw new NullPointerException("options argument cannot be null");
                }
                this.options = options;
        }
        
        /**
         * Returns the options set containing the selected command options. Returns
         * an empty options set if no option has been selected.
         * 
         * @return set with the selected options
         */
        public UniqOptions getOptions() {
                return options;
        }

        /**
         * Constructor string arguments encoding options and arguments, possibly
         * also containing variable expressions. 
         * 
         * @param args string arguments for the command
         * @throws NullPointerException if args is null
         */
        public UniqArguments(String... args) {
                this();
                this.args = args;
                this.argsIsSet = true;
        }
        private Object[] resolveVariables(VariableContext context, String... unresolved) {
                final Object[] resolved = new Object[unresolved.length];
                for (int i = 0; i < resolved.length; i++) {
                        final String expression = unresolved[i];
                        if (Arg.isVariable(expression)) {
                                resolved[i] = resolveVariable(context, expression);
                        } else {
                                resolved[i] = expression;
                        }
                }
                return resolved;
        }
        private <V> V convertList(ExecutionContext context, String operandName, Class<V> operandType, List<Object> values) {
                if (values.size() == 1) {
                        final Object value = values.get(0);
                        return convert(context, operandName, operandType, value);
                }
                return convert(context, operandName, operandType, values);
        }

        private Object resolveVariable(VariableContext context, String variable) {
                final Object value = context.getValue(variable);
                if (value != null) {
                        return value;
                }
                throw new IllegalArgumentException("cannot resolve variable " + variable + 
                                " in command: uniq " + this);
        }
        private <V> V convert(ExecutionContext context, String operandName, Class<V> operandType, Object value) {
                final ValueConverter<V> converter = context.getValueConverterFor(operandType);
                final V convertedValue;
                if (converter != null) {
                        convertedValue = converter.convert(value);
                } else {
                        if (UniqOptions.class.equals(operandType)) {
                                convertedValue = operandType.cast(UniqOptions.CONVERTER.convert(value));
                        } else {
                                convertedValue = null;
                        }
                }
                if (convertedValue != null) {
                        return convertedValue;
                }
                throw new IllegalArgumentException("cannot convert --" + operandName + 
                                " value '" + value + "' into the type " + operandType.getName() + 
                                " for uniq command");
        }
        
        @Override
        public UniqArguments getForContext(ExecutionContext context) {
                if (context == null) {
                        throw new NullPointerException("context cannot be null");
                }
                if (!argsIsSet || args.length == 0) {
                        //nothing to resolve
                        return this;
                }

                //check if there is at least one variable
                boolean hasVariable = false;
                for (final String arg : args) {
                        if (arg != null && arg.startsWith("$")) {
                                hasVariable = true;
                                break;
                        }
                }
                //resolve variables
                final Object[] resolvedArgs = hasVariable ? resolveVariables(context.getVariableContext(), this.args) : this.args;
                
                //convert now
                final List<String> defaultOperands = Arrays.asList("path");
                final Map<String, List<Object>> map = ArgsUtil.parseArgs("options", defaultOperands, resolvedArgs);
                final UniqOptions.Default options = new UniqOptions.Default();
                final UniqArguments argsForContext = new UniqArguments(options);
                for (final Map.Entry<String, List<Object>> e : map.entrySet()) {
                        if ("file".equals(e.getKey())) {
                                        
                                final java.io.File value = convertList(context, "file", java.io.File.class, e.getValue());  
                                argsForContext.setFile(value);
                        } else if ("path".equals(e.getKey())) {
                                        
                                final String value = convertList(context, "path", String.class, e.getValue());  
                                argsForContext.setPath(value);
                        } else if ("args".equals(e.getKey())) {
                                throw new IllegalStateException("invalid operand '" + e.getKey() + "' in uniq command args: " + Arrays.toString(args));
                        } else if ("options".equals(e.getKey())) {
                                        
                                final UniqOptions value = convertList(context, "options", UniqOptions.class, e.getValue());  
                                options.setAll(value);
                        } else {
                                throw new IllegalStateException("invalid operand '" + e.getKey() + "' in uniq command args: " + Arrays.toString(args));
                        }
                }
                return argsForContext;
        }
        
        /**
         * Returns the {@code <file>} operand value: The files or directories used as starting point for the listing; 
                        relative paths are not resolved (use the string path argument to 
                        enable relative path resolving based on the current working 
                        directory).
         * 
         * @return the {@code <file>} operand value (variables are not resolved)
         * @throws IllegalStateException if this operand has never been set
         * 
         */
        public java.io.File getFile() {
                if (fileIsSet) {
                        return file;
                }
                throw new IllegalStateException("operand has not been set: " + file);
        }

        /**
         * Returns true if the {@code <file>} operand has been set. 
         * <p>
         * Note that this method returns true even if {@code null} was passed to the
         * {@link #setFile(java.io.File)} method.
         * 
         * @return      true if the setter for the {@code <file>} operand has 
         *                      been called at least once
         */
        public boolean isFileSet() {
                return fileIsSet;
        }
        /**
         * Sets {@code <file>}: The files or directories used as starting point for the listing; 
                        relative paths are not resolved (use the string path argument to 
                        enable relative path resolving based on the current working 
                        directory).
         * 
         * @param file the value for the {@code <file>} operand
         */
        public void setFile(java.io.File file) {
                this.file = file;
                this.fileIsSet = true;
        }
        /**
         * Returns the {@code <path>} operand value (variables are NOT resolved): The files or directories used as starting point for the listing; 
                        wildcards * and ? are supported; relative paths are resolved on the
            basis of the current working directory.
         * 
         * @return the {@code <path>} operand value (variables are not resolved)
         * @throws IllegalStateException if this operand has never been set
         * @see #getPath(ExecutionContext)
         */
        public String getPath() {
                if (pathIsSet) {
                        return path;
                }
                throw new IllegalStateException("operand has not been set: " + path);
        }
        /**
         * Returns the {@code <path>} (variables are resolved): The files or directories used as starting point for the listing; 
                        wildcards * and ? are supported; relative paths are resolved on the
            basis of the current working directory.
         * 
         * @param context the execution context used to resolve variables
         * @return the {@code <path>} operand value after resolving variables
         * @throws IllegalStateException if this operand has never been set
         * @see #getPath()
         */
        public String getPath(ExecutionContext context) {
                final String value = getPath();
                if (Arg.isVariable(value)) {
                        final Object resolved = resolveVariable(context.getVariableContext(), value);
                        final String converted = convert(context, "path", String.class, resolved);
                        return converted;
                }
                return value;
        }

        /**
         * Returns true if the {@code <path>} operand has been set. 
         * <p>
         * Note that this method returns true even if {@code null} was passed to the
         * {@link #setPath(String)} method.
         * 
         * @return      true if the setter for the {@code <path>} operand has 
         *                      been called at least once
         */
        public boolean isPathSet() {
                return pathIsSet;
        }
        /**
         * Sets {@code <path>}: The files or directories used as starting point for the listing; 
                        wildcards * and ? are supported; relative paths are resolved on the
            basis of the current working directory.
         * 
         * @param path the value for the {@code <path>} operand
         */
        public void setPath(String path) {
                this.path = path;
                this.pathIsSet = true;
        }
        /**
         * Returns the {@code <args>} operand value: String arguments defining the options and operands for the command. 
                        Options can be specified by acronym (with a leading dash "-") or by 
                        long name (with two leading dashes "--"). Operands other than the
                        default "--path" operand have to be prefixed with the operand 
                        name.
         * 
         * @return the {@code <args>} operand value (variables are not resolved)
         * @throws IllegalStateException if this operand has never been set
         * 
         */
        public String[] getArgs() {
                if (argsIsSet) {
                        return args;
                }
                throw new IllegalStateException("operand has not been set: " + args);
        }

        /**
         * Returns true if the {@code <args>} operand has been set. 
         * 
         * @return      true if the setter for the {@code <args>} operand has 
         *                      been called at least once
         */
        public boolean isArgsSet() {
                return argsIsSet;
        }
        
        /**
         * Returns true if the {@code --}{@link UniqOption#count count} option
         * is set. The option is also known as {@code -}c option.
         * <p>
         * Description: Precedes each output line with a count of the number of times the
                        line occurred in the input.
         * 
         * @return true if the {@code --count} or {@code -c} option is set
         */
        public boolean isCount() {
                return getOptions().isSet(UniqOption.count);
        }
        /**
         * Returns true if the {@code --}{@link UniqOption#duplicatedOnly duplicatedOnly} option
         * is set. The option is also known as {@code -}d option.
         * <p>
         * Description: Suppresses the writing of lines that are not repeated in the input.
         * 
         * @return true if the {@code --duplicatedOnly} or {@code -d} option is set
         */
        public boolean isDuplicatedOnly() {
                return getOptions().isSet(UniqOption.duplicatedOnly);
        }
        /**
         * Returns true if the {@code --}{@link UniqOption#uniqueOnly uniqueOnly} option
         * is set. The option is also known as {@code -}u option.
         * <p>
         * Description: Suppresses the writing of lines that are repeated in the input.
         * 
         * @return true if the {@code --uniqueOnly} or {@code -u} option is set
         */
        public boolean isUniqueOnly() {
                return getOptions().isSet(UniqOption.uniqueOnly);
        }
        /**
         * Returns true if the {@code --}{@link UniqOption#global global} option
         * is set. The option is also known as {@code -}g option.
         * <p>
         * Description: Suppresses repeated lines globally, that is, if lines are 
                        non-adjacent. This option guarantees unique output lines even if the
                        input lines are not sorted.
         * 
         * @return true if the {@code --global} or {@code -g} option is set
         */
        public boolean isGlobal() {
                return getOptions().isSet(UniqOption.global);
        }

        @Override
        public String toString() {
                // ok, we have options or arguments or both
                final StringBuilder sb = new StringBuilder();

                if (argsIsSet) {
                        for (String arg : args) {
                                if (sb.length() > 0) sb.append(' ');
                                sb.append(arg);
                        }
                } else {
                
                        // first the options
                        if (options.size() > 0) {
                                sb.append(DefaultOptionSet.toString(options));
                        }
                        // operand: <file>
                        if (fileIsSet) {
                                if (sb.length() > 0) sb.append(' ');
                                sb.append("--").append("file");
                                sb.append(" ").append(toString(getFile()));
                        }
                        // operand: <path>
                        if (pathIsSet) {
                                if (sb.length() > 0) sb.append(' ');
                                sb.append("--").append("path");
                                sb.append(" ").append(toString(getPath()));
                        }
                        // operand: <args>
                        if (argsIsSet) {
                                if (sb.length() > 0) sb.append(' ');
                                sb.append("--").append("args");
                                sb.append(" ").append(toString(getArgs()));
                        }
                }
                
                return sb.toString();
        }
        private static String toString(Object value) {
                if (value != null && value.getClass().isArray()) {
                        return ArrayUtil.toString(value);
                }
                return String.valueOf(value);
        }
}