#!/usr/bin/env bash
# Prints the target path; use with:
#   cd "$(sidestep <region> [nonprod|prod])"
# Or add this wrapper to ~/.zshrc so plain "sidestep <region>" cds directly:
#   sidestep() { local d; d="$(command sidestep "$@")" && cd "$d"; }

set -euo pipefail

region="${1-}"
env="${2-}"

if [[ -z "$region" ]]; then
    echo "sidestep: usage: sidestep <region> [nonprod|prod]" >&2
    exit 1
fi

# Split PWD into path segments; IFS scoped to read only — avoids the bash 3.2
# bug that corrupts ${array[*]:offset:N} when a local IFS is set.
IFS='/' read -ra segs <<< "$PWD"

# Locate the *-hosting segment (0-indexed).
idx=-1
for i in "${!segs[@]}"; do
    if [[ "${segs[$i]}" == *-hosting ]]; then
        idx=$i
        break
    fi
done

if [[ $idx -eq -1 ]]; then
    echo "sidestep: not inside a *-hosting directory" >&2
    exit 1
fi

# Determine the target tier: keep current unless an env was given.
tier="${segs[$idx]}"
case "$env" in
    '')      ;;
    nonprod) tier="staging-hosting" ;;
    prod)    tier="prod-hosting" ;;
    *)
        echo "sidestep: unknown env '$env' (expected nonprod or prod)" >&2
        exit 1
        ;;
esac

# prefix = everything before the tier segment, joined by /.
# Uses printf to avoid the bash 3.2 0x7f corruption from ${array[*]:...} with custom IFS.
prefix=$(printf '%s/' "${segs[@]:0:$idx}")
prefix="${prefix%/}"

# subpath = everything after the region segment (tier+2 onward), preserved as-is.
sub_start=$((idx + 2))
sub=("${segs[@]:$sub_start}")

dest="${prefix}/${tier}/${region}"
if [[ ${#sub[@]} -gt 0 ]]; then
    subpath=$(printf '%s/' "${sub[@]}")
    dest="${dest}/${subpath%/}"
fi

if [[ ! -d "$dest" ]]; then
    echo "sidestep: directory does not exist: $dest" >&2
    exit 1
fi

printf '%s\n' "$dest"