package cobra

import (

	"bytes"

	"fmt"

	"io"

	"os"

)

// GenZshCompletionFile generates zsh completion file including descriptions.

func (c *Command) GenZshCompletionFile(filename string) error {

	return c.genZshCompletionFile(filename, true)

}

// GenZshCompletion generates zsh completion file including descriptions

// and writes it to the passed writer.

func (c *Command) GenZshCompletion(w io.Writer) error {

	return c.genZshCompletion(w, true)

}

// GenZshCompletionFileNoDesc generates zsh completion file without descriptions.

func (c *Command) GenZshCompletionFileNoDesc(filename string) error {

	return c.genZshCompletionFile(filename, false)

}

// GenZshCompletionNoDesc generates zsh completion file without descriptions

// and writes it to the passed writer.

func (c *Command) GenZshCompletionNoDesc(w io.Writer) error {

	return c.genZshCompletion(w, false)

}

// MarkZshCompPositionalArgumentFile only worked for zsh and its behavior was

// not consistent with Bash completion. It has therefore been disabled.

// Instead, when no other completion is specified, file completion is done by

// default for every argument. One can disable file completion on a per-argument

// basis by using ValidArgsFunction and ShellCompDirectiveNoFileComp.

// To achieve file extension filtering, one can use ValidArgsFunction and

// ShellCompDirectiveFilterFileExt.

//

// Deprecated

func (c *Command) MarkZshCompPositionalArgumentFile(argPosition int, patterns ...string) error {

	return nil

}

// MarkZshCompPositionalArgumentWords only worked for zsh. It has therefore

// been disabled.

// To achieve the same behavior across all shells, one can use

// ValidArgs (for the first argument only) or ValidArgsFunction for

// any argument (can include the first one also).

//

// Deprecated

func (c *Command) MarkZshCompPositionalArgumentWords(argPosition int, words ...string) error {

	return nil

}

func (c *Command) genZshCompletionFile(filename string, includeDesc bool) error {

	outFile, err := os.Create(filename)

	if err != nil {

		return err

	}

	defer outFile.Close()

	return c.genZshCompletion(outFile, includeDesc)

}

func (c *Command) genZshCompletion(w io.Writer, includeDesc bool) error {

	buf := new(bytes.Buffer)

	genZshComp(buf, c.Name(), includeDesc)

	_, err := buf.WriteTo(w)

	return err

}

func genZshComp(buf io.StringWriter, name string, includeDesc bool) {

	compCmd := ShellCompRequestCmd

	if !includeDesc {

		compCmd = ShellCompNoDescRequestCmd

	}

	WriteStringAndCheck(buf, fmt.Sprintf(`#compdef %[1]s

# zsh completion for %-36[1]s -*- shell-script -*-

__%[1]s_debug()

{

    local file="$BASH_COMP_DEBUG_FILE"

    if [[ -n ${file} ]]; then

        echo "$*" >> "${file}"

    fi

}

_%[1]s()

{

    local shellCompDirectiveError=%[3]d

    local shellCompDirectiveNoSpace=%[4]d

    local shellCompDirectiveNoFileComp=%[5]d

    local shellCompDirectiveFilterFileExt=%[6]d

    local shellCompDirectiveFilterDirs=%[7]d

    local lastParam lastChar flagPrefix requestComp out directive comp lastComp noSpace

    local -a completions

    __%[1]s_debug "\n========= starting completion logic =========="

    __%[1]s_debug "CURRENT: ${CURRENT}, words[*]: ${words[*]}"

    # The user could have moved the cursor backwards on the command-line.

    # We need to trigger completion from the $CURRENT location, so we need

    # to truncate the command-line ($words) up to the $CURRENT location.

    # (We cannot use $CURSOR as its value does not work when a command is an alias.)

    words=("${=words[1,CURRENT]}")

    __%[1]s_debug "Truncated words[*]: ${words[*]},"

    lastParam=${words[-1]}

    lastChar=${lastParam[-1]}

    __%[1]s_debug "lastParam: ${lastParam}, lastChar: ${lastChar}"

    # For zsh, when completing a flag with an = (e.g., %[1]s -n=<TAB>)

    # completions must be prefixed with the flag

    setopt local_options BASH_REMATCH

    if [[ "${lastParam}" =~ '-.*=' ]]; then

        # We are dealing with a flag with an =

        flagPrefix="-P ${BASH_REMATCH}"

    fi

    # Prepare the command to obtain completions

    requestComp="${words[1]} %[2]s ${words[2,-1]}"

    if [ "${lastChar}" = "" ]; then

        # If the last parameter is complete (there is a space following it)

        # We add an extra empty parameter so we can indicate this to the go completion code.

        __%[1]s_debug "Adding extra empty parameter"

        requestComp="${requestComp} \"\""

    fi

    __%[1]s_debug "About to call: eval ${requestComp}"

    # Use eval to handle any environment variables and such

    out=$(eval ${requestComp} 2>/dev/null)

    __%[1]s_debug "completion output: ${out}"

    # Extract the directive integer following a : from the last line

    local lastLine

    while IFS='\n' read -r line; do

        lastLine=${line}

    done < <(printf "%%s\n" "${out[@]}")

    __%[1]s_debug "last line: ${lastLine}"

    if [ "${lastLine[1]}" = : ]; then

        directive=${lastLine[2,-1]}

        # Remove the directive including the : and the newline

        local suffix

        (( suffix=${#lastLine}+2))

        out=${out[1,-$suffix]}

    else

        # There is no directive specified.  Leave $out as is.

        __%[1]s_debug "No directive found.  Setting do default"

        directive=0

    fi

    __%[1]s_debug "directive: ${directive}"

    __%[1]s_debug "completions: ${out}"

    __%[1]s_debug "flagPrefix: ${flagPrefix}"

    if [ $((directive & shellCompDirectiveError)) -ne 0 ]; then

        __%[1]s_debug "Completion received error. Ignoring completions."

        return

    fi

    local activeHelpMarker="%[8]s"

    local endIndex=${#activeHelpMarker}

    local startIndex=$((${#activeHelpMarker}+1))

    local hasActiveHelp=0

    while IFS='\n' read -r comp; do

        # Check if this is an activeHelp statement (i.e., prefixed with $activeHelpMarker)

        if [ "${comp[1,$endIndex]}" = "$activeHelpMarker" ];then

            __%[1]s_debug "ActiveHelp found: $comp"

            comp="${comp[$startIndex,-1]}"

            if [ -n "$comp" ]; then

                compadd -x "${comp}"

                __%[1]s_debug "ActiveHelp will need delimiter"

                hasActiveHelp=1

            fi

            continue

        fi

        if [ -n "$comp" ]; then

            # If requested, completions are returned with a description.

            # The description is preceded by a TAB character.

            # For zsh's _describe, we need to use a : instead of a TAB.

            # We first need to escape any : as part of the completion itself.

            comp=${comp//:/\\:}

            local tab="$(printf '\t')"

            comp=${comp//$tab/:}

            __%[1]s_debug "Adding completion: ${comp}"

            completions+=${comp}

            lastComp=$comp

        fi

    done < <(printf "%%s\n" "${out[@]}")

    # Add a delimiter after the activeHelp statements, but only if:

    # - there are completions following the activeHelp statements, or

    # - file completion will be performed (so there will be choices after the activeHelp)

    if [ $hasActiveHelp -eq 1 ]; then

        if [ ${#completions} -ne 0 ] || [ $((directive & shellCompDirectiveNoFileComp)) -eq 0 ]; then

            __%[1]s_debug "Adding activeHelp delimiter"

            compadd -x "--"

            hasActiveHelp=0

        fi

    fi

    if [ $((directive & shellCompDirectiveNoSpace)) -ne 0 ]; then

        __%[1]s_debug "Activating nospace."

        noSpace="-S ''"

    fi

    if [ $((directive & shellCompDirectiveFilterFileExt)) -ne 0 ]; then

        # File extension filtering

        local filteringCmd

        filteringCmd='_files'

        for filter in ${completions[@]}; do

            if [ ${filter[1]} != '*' ]; then

                # zsh requires a glob pattern to do file filtering

                filter="\*.$filter"

            fi

            filteringCmd+=" -g $filter"

        done

        filteringCmd+=" ${flagPrefix}"

        __%[1]s_debug "File filtering command: $filteringCmd"

        _arguments '*:filename:'"$filteringCmd"

    elif [ $((directive & shellCompDirectiveFilterDirs)) -ne 0 ]; then

        # File completion for directories only

        local subdir

        subdir="${completions[1]}"

        if [ -n "$subdir" ]; then

            __%[1]s_debug "Listing directories in $subdir"

            pushd "${subdir}" >/dev/null 2>&1

        else

            __%[1]s_debug "Listing directories in ."

        fi

        local result

        _arguments '*:dirname:_files -/'" ${flagPrefix}"

        result=$?

        if [ -n "$subdir" ]; then

            popd >/dev/null 2>&1

        fi

        return $result

    else

        __%[1]s_debug "Calling _describe"

        if eval _describe "completions" completions $flagPrefix $noSpace; then

            __%[1]s_debug "_describe found some completions"

            # Return the success of having called _describe

            return 0

        else

            __%[1]s_debug "_describe did not find completions."

            __%[1]s_debug "Checking if we should do file completion."

            if [ $((directive & shellCompDirectiveNoFileComp)) -ne 0 ]; then

                __%[1]s_debug "deactivating file completion"

                # We must return an error code here to let zsh know that there were no

                # completions found by _describe; this is what will trigger other

                # matching algorithms to attempt to find completions.

                # For example zsh can match letters in the middle of words.

                return 1

            else

                # Perform file completion

                __%[1]s_debug "Activating file completion"

                # We must return the result of this command, so it must be the

                # last command, or else we must store its result to return it.

                _arguments '*:filename:_files'" ${flagPrefix}"

            fi

        fi

    fi

}

# don't run the completion function when being source-ed or eval-ed

if [ "$funcstack[1]" = "_%[1]s" ]; then

    _%[1]s

fi

`, name, compCmd,

		ShellCompDirectiveError, ShellCompDirectiveNoSpace, ShellCompDirectiveNoFileComp,

		ShellCompDirectiveFilterFileExt, ShellCompDirectiveFilterDirs,

		activeHelpMarker))

}