#!/bin/bash
#===============================================================================
# Felhom App Catalog - Customer Repo Renderer v1.0
#
# Reads customer YAML configs and generates per-customer stack directories
# by substituting {{DOMAIN}} placeholders in Docker Compose templates.
#
# Usage:
#   ./render.sh                          # Render all customers
#   ./render.sh --customer demo-felhom   # Render specific customer
#   ./render.sh --dry-run                # Show what would be done
#   ./render.sh --push                   # Render + push to Gitea
#   ./render.sh --output-dir /tmp/out    # Custom output directory
#   ./render.sh --debug                  # Verbose output
#
# Prerequisites:
#   - git (for push mode)
#   - Access to Gitea (for push mode)
#
#===============================================================================

set -euo pipefail

#-------------------------------------------------------------------------------
# Configuration
#-------------------------------------------------------------------------------
SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
CATALOG_DIR="$(cd "${SCRIPT_DIR}/.." && pwd)"
TEMPLATES_DIR="${CATALOG_DIR}/templates"
CUSTOMERS_DIR="${CATALOG_DIR}/customers"
DEFAULT_OUTPUT_DIR="${CATALOG_DIR}/output"

# Gitea settings (for --push mode)
GITEA_URL="${GITEA_URL:-https://gitea.felhom.eu}"
GITEA_ORG="${GITEA_ORG:-customers}"

#-------------------------------------------------------------------------------
# Colors & Logging
#-------------------------------------------------------------------------------
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
CYAN='\033[0;36m'
BOLD='\033[1m'
NC='\033[0m'

log_info()    { echo -e "${CYAN}[INFO]${NC} $*"; }
log_success() { echo -e "${GREEN}[OK]${NC} $*"; }
log_warn()    { echo -e "${YELLOW}[WARN]${NC} $*"; }
log_error()   { echo -e "${RED}[ERROR]${NC} $*" >&2; }
log_debug()   { [[ "${DEBUG:-false}" == "true" ]] && echo -e "[DEBUG] $*" || true; }
log_step()    { echo -e "\n${BOLD}[STEP]${NC} $*"; }

#-------------------------------------------------------------------------------
# Simple YAML parser (no external dependencies)
# Handles our flat customer YAML format
#-------------------------------------------------------------------------------
yaml_get_value() {
    # Get a simple key: value from YAML file
    local file="$1" key="$2"
    grep -E "^${key}:" "$file" 2>/dev/null | sed "s/^${key}:[[:space:]]*//" | sed 's/^"//' | sed 's/"$//' | sed "s/^'//" | sed "s/'$//" || echo ""
}

yaml_get_list() {
    # Get a YAML list (items starting with "  - ")
    local file="$1" key="$2"
    local in_section=false
    while IFS= read -r line; do
        if [[ "$line" =~ ^${key}: ]]; then
            in_section=true
            continue
        fi
        if $in_section; then
            if [[ "$line" =~ ^[[:space:]]*-[[:space:]]+(.*) ]]; then
                echo "${BASH_REMATCH[1]}" | sed 's/^"//' | sed 's/"$//'
            elif [[ "$line" =~ ^[a-zA-Z_] ]] || [[ -z "$line" && "$in_section" == true ]]; then
                # New top-level key or empty line after list = end of section
                # But only break on a new top-level key, not empty lines within
                if [[ "$line" =~ ^[a-zA-Z_] ]]; then
                    break
                fi
            fi
        fi
    done < "$file"
}

yaml_get_override() {
    # Get a specific override value: overrides.key
    local file="$1" key="$2"
    local in_overrides=false
    while IFS= read -r line; do
        if [[ "$line" =~ ^overrides: ]]; then
            in_overrides=true
            continue
        fi
        if $in_overrides; then
            if [[ "$line" =~ ^[[:space:]]+${key}:[[:space:]]*(.*) ]]; then
                local val="${BASH_REMATCH[1]}"
                echo "$val" | sed 's/^"//' | sed 's/"$//' | sed "s/^'//" | sed "s/'$//"
                return
            fi
            if [[ "$line" =~ ^[a-zA-Z_] ]]; then
                break
            fi
        fi
    done < "$file"
    echo ""
}

#-------------------------------------------------------------------------------
# Template rendering
#-------------------------------------------------------------------------------
render_customer() {
    local customer_file="$1"
    local output_base="$2"

    local customer_id domain hdd_path
    customer_id=$(yaml_get_value "$customer_file" "customer_id")
    domain=$(yaml_get_value "$customer_file" "domain")
    hdd_path=$(yaml_get_value "$customer_file" "hdd_path")

    if [[ -z "$customer_id" || -z "$domain" ]]; then
        log_error "Missing customer_id or domain in: $customer_file"
        return 1
    fi

    log_step "Rendering customer: ${BOLD}${customer_id}${NC} (${domain})"

    # Check auto_update override
    local auto_update
    auto_update=$(yaml_get_override "$customer_file" "auto_update")
    if [[ "$auto_update" == "false" ]]; then
        log_warn "auto_update=false — skipping this customer"
        return 0
    fi

    # Get app list
    local apps=()
    while IFS= read -r app; do
        [[ -n "$app" ]] && apps+=("$app")
    done < <(yaml_get_list "$customer_file" "apps")

    if [[ ${#apps[@]} -eq 0 ]]; then
        log_warn "No apps configured for $customer_id"
        return 0
    fi

    log_info "Apps: ${apps[*]}"
    log_info "Domain: $domain"
    if [[ -n "$hdd_path" ]]; then
        log_info "HDD path: $hdd_path"
    fi

    # Output directory for this customer
    local customer_output="${output_base}/${customer_id}-stacks"

    if [[ "$DRY_RUN" == "true" ]]; then
        echo -e "  ${CYAN}[DRY-RUN]${NC} Would create: ${customer_output}/"
        for app in "${apps[@]}"; do
            echo -e "  ${CYAN}[DRY-RUN]${NC}   ${app}/docker-compose.yml  ({{DOMAIN}} → ${domain})"
            # Check if template uses HDD_PATH
            local template="${TEMPLATES_DIR}/${app}/docker-compose.yml"
            if [[ -f "$template" ]] && grep -q '{{HDD_PATH}}' "$template"; then
                if [[ -n "$hdd_path" ]]; then
                    echo -e "  ${CYAN}[DRY-RUN]${NC}     ↳ HDD path: {{HDD_PATH}} → ${hdd_path}"
                else
                    echo -e "  ${YELLOW}[DRY-RUN]${NC}     ↳ ⚠ Template uses {{HDD_PATH}} but hdd_path not set!"
                fi
            fi
            # Show version override if any
            local version_override
            version_override=$(yaml_get_override "$customer_file" "${app}_version")
            if [[ -n "$version_override" ]]; then
                echo -e "  ${CYAN}[DRY-RUN]${NC}     ↳ version pinned to: ${version_override}"
            fi
        done
        return 0
    fi

    # Create output directory
    mkdir -p "$customer_output"

    # Generate a README for the customer repo
    cat > "${customer_output}/README.md" << EOF
# ${customer_id} - Application Stacks

**Domain:** \`${domain}\`
**HDD Path:** \`${hdd_path:-N/A (no HDD apps)}\`
**Generated:** $(date -u '+%Y-%m-%d %H:%M:%S UTC')
**Source:** felhom-app-catalog (render.sh)

## Deployed Apps

| App | Compose Path |
|-----|-------------|
$(for app in "${apps[@]}"; do echo "| ${app} | \`${app}/docker-compose.yml\` |"; done)

## Portainer Setup

For each app, create a stack in Portainer:
1. **Stacks → Add Stack → Repository**
2. Repository URL: \`${GITEA_URL}/${GITEA_ORG}/${customer_id}-stacks\`
3. Compose path: \`<appname>/docker-compose.yml\`
4. Add required environment variables (see comments in compose files)
5. Deploy

---
*Auto-generated by felhom-app-catalog. Do not edit manually.*
EOF

    # Process each app
    local rendered_count=0
    for app in "${apps[@]}"; do
        local template="${TEMPLATES_DIR}/${app}/docker-compose.yml"

        if [[ ! -f "$template" ]]; then
            log_error "Template not found: ${template}"
            continue
        fi

        mkdir -p "${customer_output}/${app}"

        # Substitute {{DOMAIN}} with customer domain
        sed "s/{{DOMAIN}}/${domain}/g" "$template" > "${customer_output}/${app}/docker-compose.yml"

        # Substitute {{HDD_PATH}} if the template uses it
        if grep -q '{{HDD_PATH}}' "${customer_output}/${app}/docker-compose.yml"; then
            if [[ -z "$hdd_path" ]]; then
                log_error "  ${app}: template uses {{HDD_PATH}} but hdd_path not set in customer config!"
                log_error "  Add 'hdd_path: /mnt/hdd_1' (or similar) to ${customer_file}"
                rm "${customer_output}/${app}/docker-compose.yml"
                rmdir "${customer_output}/${app}" 2>/dev/null || true
                continue
            fi
            # Remove trailing slash from hdd_path if present
            local clean_hdd_path="${hdd_path%/}"
            sed -i "s|{{HDD_PATH}}|${clean_hdd_path}|g" "${customer_output}/${app}/docker-compose.yml"
        fi

        # Apply version override if configured
        local version_override
        version_override=$(yaml_get_override "$customer_file" "${app}_version")
        if [[ -n "$version_override" ]]; then
            log_info "  ${app}: applying version override → ${version_override}"
            # Find the main image line and replace the tag
            # This is a simple approach — works for single-image apps and
            # the first image line in multi-service apps
            case "$app" in
                immich)
                    # Immich has server + ML images that should match
                    sed -i "s|ghcr.io/immich-app/immich-server:[^ ]*|ghcr.io/immich-app/immich-server:${version_override}|g" \
                        "${customer_output}/${app}/docker-compose.yml"
                    sed -i "s|ghcr.io/immich-app/immich-machine-learning:[^ ]*|ghcr.io/immich-app/immich-machine-learning:${version_override}|g" \
                        "${customer_output}/${app}/docker-compose.yml"
                    ;;
                *)
                    # Generic: replace the first image tag (main service)
                    # Get the first image line and replace its tag
                    local first_image
                    first_image=$(grep -m1 "image:" "${customer_output}/${app}/docker-compose.yml" | sed 's/.*image:[[:space:]]*//')
                    if [[ -n "$first_image" ]]; then
                        local image_name
                        image_name=$(echo "$first_image" | cut -d: -f1)
                        sed -i "s|${first_image}|${image_name}:${version_override}|" \
                            "${customer_output}/${app}/docker-compose.yml"
                    fi
                    ;;
            esac
        fi

        rendered_count=$((rendered_count + 1))
        log_debug "  Rendered: ${app}/docker-compose.yml"
    done

    log_success "Rendered ${rendered_count}/${#apps[@]} apps → ${customer_output}/"
}

#-------------------------------------------------------------------------------
# Git push to Gitea
#-------------------------------------------------------------------------------
push_to_gitea() {
    local customer_dir="$1"
    local customer_id
    customer_id=$(basename "$customer_dir" | sed 's/-stacks$//')

    local repo_url="${GITEA_URL}/${GITEA_ORG}/${customer_id}-stacks.git"

    log_step "Pushing to Gitea: ${repo_url}"

    cd "$customer_dir"

    if [[ ! -d ".git" ]]; then
        git init -b main
        git remote add origin "$repo_url"
    fi

    git add -A
    if git diff --cached --quiet; then
        log_info "No changes to push for ${customer_id}"
        return 0
    fi

    git commit -m "Auto-render: $(date -u '+%Y-%m-%d %H:%M:%S UTC')"

    if git push origin main 2>/dev/null; then
        log_success "Pushed to ${repo_url}"
    else
        # Try force push if first time or diverged
        log_warn "Normal push failed, trying force push..."
        git push -u origin main --force
        log_success "Force-pushed to ${repo_url}"
    fi
}

#-------------------------------------------------------------------------------
# Argument parsing
#-------------------------------------------------------------------------------
DRY_RUN=false
PUSH=false
DEBUG=false
TARGET_CUSTOMER=""
OUTPUT_DIR=""

print_help() {
    cat << 'EOF'
Felhom App Catalog - Customer Repo Renderer v1.0

Generates per-customer Docker Compose stacks from templates.

USAGE:
    ./render.sh [OPTIONS]

OPTIONS:
    --customer ID       Render only this customer
    --output-dir DIR    Output directory (default: ./output/)
    --push              Push rendered repos to Gitea
    --dry-run           Show what would be done
    --debug             Verbose output
    -h, --help          Show this help

ENVIRONMENT VARIABLES:
    GITEA_URL           Gitea base URL (default: https://gitea.felhom.eu)
    GITEA_ORG           Gitea organization (default: customers)

EXAMPLES:
    ./render.sh                              # Render all customers
    ./render.sh --customer demo-felhom       # Render one customer
    ./render.sh --dry-run                    # Preview changes
    ./render.sh --push                       # Render + push to Gitea
EOF
}

while [[ $# -gt 0 ]]; do
    case $1 in
        --customer)    TARGET_CUSTOMER="$2"; shift 2 ;;
        --output-dir)  OUTPUT_DIR="$2"; shift 2 ;;
        --push)        PUSH=true; shift ;;
        --dry-run)     DRY_RUN=true; shift ;;
        --debug)       DEBUG=true; shift ;;
        -h|--help)     print_help; exit 0 ;;
        *)             log_error "Unknown option: $1"; print_help; exit 1 ;;
    esac
done

OUTPUT_DIR="${OUTPUT_DIR:-${DEFAULT_OUTPUT_DIR}}"

#-------------------------------------------------------------------------------
# Main
#-------------------------------------------------------------------------------
main() {
    echo ""
    echo -e "${BOLD}Felhom App Catalog — Renderer${NC}"
    echo -e "Templates: ${TEMPLATES_DIR}"
    echo -e "Customers: ${CUSTOMERS_DIR}"
    echo -e "Output:    ${OUTPUT_DIR}"
    echo ""

    # Validate directories exist
    if [[ ! -d "$TEMPLATES_DIR" ]]; then
        log_error "Templates directory not found: $TEMPLATES_DIR"
        exit 1
    fi
    if [[ ! -d "$CUSTOMERS_DIR" ]]; then
        log_error "Customers directory not found: $CUSTOMERS_DIR"
        exit 1
    fi

    # Find customer configs to process
    local customer_files=()
    if [[ -n "$TARGET_CUSTOMER" ]]; then
        local target_file="${CUSTOMERS_DIR}/${TARGET_CUSTOMER}.yaml"
        if [[ ! -f "$target_file" ]]; then
            log_error "Customer config not found: $target_file"
            exit 1
        fi
        customer_files=("$target_file")
    else
        while IFS= read -r -d '' f; do
            customer_files+=("$f")
        done < <(find "$CUSTOMERS_DIR" -name "*.yaml" -print0 | sort -z)
    fi

    if [[ ${#customer_files[@]} -eq 0 ]]; then
        log_error "No customer configs found in $CUSTOMERS_DIR"
        exit 1
    fi

    log_info "Found ${#customer_files[@]} customer(s) to render"

    # Create output directory
    if [[ "$DRY_RUN" != "true" ]]; then
        mkdir -p "$OUTPUT_DIR"
    fi

    # Render each customer
    local success_count=0
    for customer_file in "${customer_files[@]}"; do
        if render_customer "$customer_file" "$OUTPUT_DIR"; then
            success_count=$((success_count + 1))

            # Push to Gitea if requested
            if [[ "$PUSH" == "true" && "$DRY_RUN" != "true" ]]; then
                local cid
                cid=$(yaml_get_value "$customer_file" "customer_id")
                push_to_gitea "${OUTPUT_DIR}/${cid}-stacks"
            fi
        fi
    done

    echo ""
    echo -e "${BOLD}${GREEN}━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━${NC}"
    echo -e "${BOLD}${GREEN}  Rendering complete: ${success_count}/${#customer_files[@]} customers${NC}"
    echo -e "${BOLD}${GREEN}━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━${NC}"
    echo ""

    if [[ "$DRY_RUN" != "true" ]]; then
        echo -e "${BOLD}Output:${NC}"
        find "$OUTPUT_DIR" -name "docker-compose.yml" -printf "  %P\n" | sort
        echo ""
    fi

    if [[ "$PUSH" != "true" && "$DRY_RUN" != "true" ]]; then
        echo -e "${YELLOW}Tip:${NC} Use --push to automatically push to Gitea repos"
    fi
}

main