#!/usr/bin/env bash
# Migrate GitHub Actions in workflow files to use mirrored actions
# Usage: ./migrate-actions.sh <repository-path>

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
ACTIONS_LIST="${SCRIPT_DIR}/actions-to-mirror.txt"

if [[ $# -lt 1 ]]; then
    echo "Usage: $0 <repository-path>"
    echo "Example: $0 /path/to/repo"
    exit 1
fi

REPO_PATH="$1"

if [[ ! -d "$REPO_PATH" ]]; then
    echo "Error: Repository path not found: $REPO_PATH"
    exit 1
fi

if [[ ! -f "$ACTIONS_LIST" ]]; then
    echo "Error: Actions list not found at $ACTIONS_LIST"
    exit 1
fi

# Build lookup table of mirrored actions
declare -A MIRRORED_ACTIONS
while IFS= read -r line || [[ -n "$line" ]]; do
    [[ -z "$line" || "$line" =~ ^[[:space:]]*# ]] && continue
    line="$(echo "$line" | xargs)"
    # Store as key for quick lookup (e.g., "actions/checkout@v4")
    MIRRORED_ACTIONS["$line"]=1
done < "$ACTIONS_LIST"

# Find workflow files
WORKFLOW_DIR="${REPO_PATH}/.github/workflows"
if [[ ! -d "$WORKFLOW_DIR" ]]; then
    echo "Error: No .github/workflows directory found in $REPO_PATH"
    exit 1
fi

# Track unmirrored actions
declare -A UNMIRRORED_ACTIONS

# Convert action reference to mirrored path
# e.g., "actions/checkout@v4" -> "infrastructure/actions/actions/checkout-v4"
convert_action() {
    local action="$1"
    local org repo version

    # Parse org/repo@version
    org="${action%%/*}"
    local repo_version="${action#*/}"
    repo="${repo_version%%@*}"
    version="${repo_version#*@}"

    echo "infrastructure/actions/${org}/${repo}-${version}"
}

# Process a single workflow file
process_workflow() {
    local file="$1"
    local modified=false
    local temp_file
    temp_file=$(mktemp)

    while IFS= read -r line || [[ -n "$line" ]]; do
        # Check if line contains a uses: statement
        if [[ "$line" =~ ^([[:space:]]*)uses:[[:space:]]*([^[:space:]]+) ]]; then
            local indent="${BASH_REMATCH[1]}"
            local action="${BASH_REMATCH[2]}"

            # Remove quotes if present
            action="${action#\"}"
            action="${action%\"}"
            action="${action#\'}"
            action="${action%\'}"

            # Check if this is a GitHub action reference (org/repo@version format)
            if [[ "$action" =~ ^[a-zA-Z0-9_-]+/[a-zA-Z0-9_.-]+@[a-zA-Z0-9._-]+$ ]]; then
                if [[ -n "${MIRRORED_ACTIONS[$action]:-}" ]]; then
                    # Replace with mirrored version
                    local new_action
                    new_action=$(convert_action "$action")
                    echo "${indent}uses: ${new_action}" >> "$temp_file"
                    modified=true
                    echo "  Replaced: $action -> $new_action"
                else
                    # Not in our mirror list
                    UNMIRRORED_ACTIONS["$action"]+="${file##*/} "
                    echo "$line" >> "$temp_file"
                fi
            else
                # Not a standard action reference (could be local action, docker, etc.)
                echo "$line" >> "$temp_file"
            fi
        else
            echo "$line" >> "$temp_file"
        fi
    done < "$file"

    if [[ "$modified" == true ]]; then
        cp "$temp_file" "$file"
        echo "  Updated: $file"
    fi

    rm -f "$temp_file"
}

echo "Migrating workflows in: $REPO_PATH"
echo "Using actions list: $ACTIONS_LIST"
echo ""

# Process all workflow files
for workflow in "$WORKFLOW_DIR"/*.yml "$WORKFLOW_DIR"/*.yaml; do
    [[ -f "$workflow" ]] || continue
    echo "Processing: ${workflow##*/}"
    process_workflow "$workflow"
    echo ""
done

# Report unmirrored actions
if [[ ${#UNMIRRORED_ACTIONS[@]} -gt 0 ]]; then
    echo "========================================"
    echo "UNMIRRORED ACTIONS (not replaced):"
    echo "========================================"
    for action in "${!UNMIRRORED_ACTIONS[@]}"; do
        echo ""
        echo "  $action"
        echo "    Used in: ${UNMIRRORED_ACTIONS[$action]}"
    done
    echo ""
    echo "Add these to $ACTIONS_LIST and re-run clone-actions.sh to mirror them."
fi

echo ""
echo "Migration complete."