{{- if or (and (stat (joinPath .host.home ".config" "age" "chezmoi.txt")) (stat (joinPath .chezmoi.sourceDir ".chezmoitemplates" "secrets" "SENDGRID_API_KEY"))) (env "SENDGRID_API_KEY") -}}
#!/usr/bin/env bash
# @file SendGrid Postfix Configuration
# @brief Configures Postfix to use SendGrid as a relay host so you can use the `mail` program to send e-mail from the command-line
# @description
#     This script follows the instructions from [SendGrid's documentation on integrating Postfix](https://docs.sendgrid.com/for-developers/sending-email/postfix).
#     After this script runs, you should be able to send outgoing e-mails using SendGrid as an SMTP handler. In other words, you will
#     be able to use the `mail` CLI command to send e-mails. The following is an example mailing the contents of `~/.bashrc` to `name@email.com`:
#
#     ```shell
#     cat ~/.bashrc | mail -s "My subject" name@email.com
#     ```

{{ includeTemplate "universal/profile" }}
{{ includeTemplate "universal/logg" }}

if command -v postfix > /dev/null; then
    ### Ensure dependencies are installed
    if command -v apt-get > /dev/null; then
        logg info 'Installing libsasl2-modules'
        sudo apt-get update
        sudo apt-get install -y libsasl2-modules || EXIT_CODE=$?
    elif command -v dnf > /dev/null; then
        sudo dnf install -y cyrus-sasl-plain || EXIT_CODE=$?
    elif command -v yum > /dev/null; then
        sudo yum install -y cyrus-sasl-plain || EXIT_CODE=$?
    fi
    if [ -n "$EXIT_CODE" ]; then
        logg warn 'There was an error ensuring the Postfix-SendGrid dependencies were installed'
    fi

    if [ -d /etc/postfix ]; then
        ### Add the SendGrid Postfix settings to the Postfix configuration
        if [ -f "${XDG_CONFIG_HOME:-$HOME/.config}/postfix/main.cf" ]; then
            CONFIG_FILE=/etc/postfix/main.cf
            if cat "$CONFIG_FILE" | grep '### INSTALL DOCTOR MANAGED' > /dev/null; then
                logg info 'Removing Install Doctor-managed block of code in /etc/postfix/main.cf block'
                START_LINE="$(echo `grep -n -m 1 "### INSTALL DOCTOR MANAGED ### START" "$CONFIG_FILE" | cut -f1 -d ":"`)"
                END_LINE="$(echo `grep -n -m 1 "### INSTALL DOCTOR MANAGED ### END" "$CONFIG_FILE" | cut -f1 -d ":"`)"
                if [ -n "$START_LINE" ] && [ -n "$END_LINE" ]; then
                    if command -v gsed > /dev/null; then
                        sudo gsed -i "${START_LINE},${END_LINE}d" "$CONFIG_FILE"
                    else
                        sudo sed -i "${START_LINE},${END_LINE}d" "$CONFIG_FILE"
                    fi
                else
                    logg info 'No start-line or end-line detected - configuration appears to already be clean'
                fi
            fi

            ### Add Postfix main configuration
            logg "Adding the following configuration from ${XDG_CONFIG_HOME:-$HOME/.config}/postfix/main.cf to /etc/postfix/main.cf"
            cat "${XDG_CONFIG_HOME:-$HOME/.config}/postfix/main.cf" | sudo tee -a "$CONFIG_FILE" > /dev/null
            echo "" | sudo tee -a "$CONFIG_FILE" > /dev/null
        fi

        ### Ensure proper permissions on `sasl_passwd` and update Postfix hashmaps
        if [ -f "${XDG_CONFIG_HOME:-$HOME/.config}/postfix/sasl_passwd" ]; then
            logg info "Copying file from ${XDG_CONFIG_HOME:-$HOME/.config}/postfix/sasl_passwd to /etc/postfix/sasl_passwd"
            sudo cp -f "${XDG_CONFIG_HOME:-$HOME/.config}/postfix/sasl_passwd" /etc/postfix/sasl_passwd
            logg info 'Assigning proper permissions to /etc/postfix/sasl_passwd'
            sudo chmod 600 /etc/postfix/sasl_passwd
            logg info 'Updating Postfix hashmaps for /etc/postfix/sasl_passwd'
            sudo postmap /etc/postfix/sasl_passwd
        else
            logg warn '~/.config/postfix/sasl_passwd file is missing'
        fi

        ### Forward root e-mails
        if [ -d /root ]; then
            logg info 'Forwarding root e-mails to {{ .user.email }}'
            echo '{{ .user.email }}' | sudo tee /root/.forward > /dev/null || logg error 'Failed to set root user .forward file'
        elif [ -d /var/root ]; then
            logg info 'Forwarding root e-mails to {{ .user.email }}'
            echo '{{ .user.email }}' | sudo tee /var/root/.forward > /dev/null || logg error 'Failed to set root user .forward file'
        else
            logg warn 'Unable to identify root user home directory'
        fi

        ### Ensure /etc/postfix/header_checks exists
        if [ ! -d /etc/postfix/header_checks ]; then
            logg info 'Creating /etc/postfix/header_checks since it does not exist'
            sudo touch /etc/postfix/header_checks
        fi

        ### Re-write header From for SendGrid
        if ! cat /etc/postfix/header_checks | grep 'no-reply@{{ .host.domain }}' > /dev/null; then
            logg info 'Added From REPLACE to /etc/postfix/header_checks'
            echo '/^From:.*@{{ .host.domain }}/ REPLACE From: no-reply@{{ .host.domain }}' | sudo tee -a /etc/postfix/header_checks > /dev/null
        fi

        ### Update aliases
        if [ -f /etc/aliases ]; then
            logg info 'Forward root e-mails to {{ .user.email }}'
            ALIASES_TMP="$(mktemp)"
            logg info 'Setting {{ .user.email }} as root e-mail in temporary file'
            sudo sed "s/#root.*/root:\ {{ .user.email }}/" /etc/aliases > "$ALIASES_TMP"
            logg info 'Moving temporary file to /etc/aliases'
            sudo mv -f "$ALIASES_TMP" /etc/aliases
            if ! cat /etc/aliases | grep '{{ .user.username }}: root' > /dev/null; then
                logg info 'Forward user e-mail to root@localhost'
                echo '{{ .user.username }}: root' | sudo tee -a /etc/aliases > /dev/null
            fi

            ### Ensure old /etc/aliases.db is removed
            if [ -f /etc/aliases.db ]; then
                logg info 'Ensuring /etc/aliases.db is removed' && sudo rm -f /etc/aliases.db
            else
                logg info '/etc/aliases.db was not found'
            fi

            ### Re-generate the /etc/aliases.db file
            if [ -f /etc/aliases ]; then
                logg info 'Ensuring proper permissions on the /etc/aliases file' && sudo chown $(stat -c "%U:%G" /etc/sudoers) /etc/aliases
                logg info 'Generating Postfix aliases' && sudo postalias /etc/aliases > /dev/null
            else
                logg warn '/etc/aliases is missing which is required for Postfix'
            fi
            # The `sudo newaliases` mode is probably used to regenerate the /etc/aliases.db
            # but since we are removing it to ensure proper permissions, this method is commented out.
            # logg info 'Running newaliases to regenerate the alias database' && sudo newaliases
        else
            logg warn '/etc/aliases does not appear to exist'
        fi

        if [ -d /Applications ] && [ -d /System ]; then
            ### macOS
            # Source: https://budiirawan.com/install-mail-server-mac-osx/
            if [ -f "${XDG_CONFIG_HOME:-$HOME/.config}/postfix/com.apple.postfix.master.plist" ] && ! sudo launchctl list | grep 'postfix.master' > /dev/null; then
                logg info 'Copying com.apple.postfix.master.plist'
                sudo cp -f "${XDG_CONFIG_HOME:-$HOME/.config}/postfix/com.apple.postfix.master.plist" /System/Library/LaunchDaemons/com.apple.postfix.master.plist
                sudo launchctl load /System/Library/LaunchDaemons/com.apple.postfix.master.plist && logg success 'launchctl load of com.apple.postfix.master successful'
            fi
            if ! sudo postfix status > /dev/null; then
                logg info 'Starting postfix'
                sudo postfix start > /dev/null
            else
                logg info 'Reloading postfix'
                sudo postfix reload > /dev/null
            fi
        else
            ### Enable / restart postfix on Linux
            logg info 'Enabling / restarting postfix'
            sudo systemctl enable postfix
            sudo systemctl restart postfix
        fi
    else
        logg warn '/etc/postfix is not a directory! Skipping SendGrid Postfix setup.'
    fi
else
    logg info 'Skipping Postfix configuration because Postfix is not installed'
fi

{{ end -}}