#!/usr/bin/env bash
# Exit if any command fails
set -e

# Inform the user of the output they can expect.

echo "common commands:"

write_command_then_count() {
    # Get the command and count, which currently looks like:
    #   '42 git commit'
    # Then write th e command with the count afterward
    local line="$1"
    local count=$(echo "${line}" | cut -d' ' -f1)
    local command=$(echo "${line}" | cut -d' ' -f2-)
    echo "${command} (${count})"
}


# The following variables control how the command runs.
shell_binary=""             # A place to store the shell binary value
history_file=""             # A place to store the history file path
history_lines=1000          # The number of lines of history to search through
command_count=${1:-10}      # The number of common commands to show

# Check whether you can determine the name of the shell binary
shell_regex="([^/]+$)"
if [[ $SHELL =~ $shell_regex ]]; then
    # Depending on the name of the shell binary, set the history filepath
    shell_binary=${BASH_REMATCH[1]}
    if [[ $shell_binary == "bash" ]]; then
        history_file=~/.bash_history
    elif [[ $shell_binary == "zsh" ]]; then
        history_file=~/.zsh_history
    fi
fi

# If you are searching through the bash history, you can look at the history file
# to get the most common commands
if [[ $shell_binary == "bash" ]]; then
    
    # Show the most commonly used commands
    commands=$(tail "${history_file}" -n ${history_lines} \
        | sort \
        | uniq -c \
        | sed 's/^ *//' \
        | sort -n -r \
        | head -n ${command_count})

elif [[ $shell_binary == "zsh" ]]; then

    # Z shell shitory lines look like this:
    # : 1621135004:0;uname -a
    # Run the same command as above, and extract everything _after_ the
    # semicolon, which is the command text
    commands=$(tail "${history_file}" -n ${history_lines} \
        | cut -d';' -f2 \
        | sort \
        | uniq -c \
        | sed 's/^ *//' \
        | sort -n -r \
        | head -n ${command_count})
else

    # show a warning to the user that you don't know where the history file
    # is for their shell
    echo "Sorry, I don't know where to find the history file for '${SHELL}'"
fi

# Print each command, showing its order in the list
# Commands are separated by newlines, so temporarily change IFS to loop over
# each line of the commands
counter=1
old_ifs=$IFS
IFS=$'\n'
for command in $commands
do
    use_count=$(echo "$command" | cut -d' ' -f 1)
    use_command=$(echo "$command" | cut -d' ' -f 2)
    printf "$(tput bold; tput setaf 3)%-5s $(tput sgr0)$(tput setaf 6)%-5s $(tput sgr0)%-5s\n" "$counter" "$use_count" "$use_command"
    counter=$((counter + 1))
done
IFS=$old_ifs