#!/usr/bin/env bash
#
# validate-paths.sh - Validates offline kit path structure
#
# Usage: ./validate-paths.sh [--combined] [kit_directory]
#
# Options:
#   --combined     Expect combined runtime format (combined.runtime.ndjson)
#   kit_directory  Path to kit directory (default: parent of this script)
#
# Exit codes:
#   0 - All validations passed
#   1 - Missing required files or directories
#   2 - Invalid file format
#   3 - Usage error

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
COMBINED_FORMAT=false
KIT_DIR=""

# Parse arguments
while [[ $# -gt 0 ]]; do
    case "$1" in
        --combined)
            COMBINED_FORMAT=true
            shift
            ;;
        --help|-h)
            echo "Usage: $0 [--combined] [kit_directory]"
            echo ""
            echo "Validates offline kit path structure and file formats."
            echo ""
            echo "Options:"
            echo "  --combined     Expect combined runtime format"
            echo "  kit_directory  Path to kit directory (default: parent of this script)"
            exit 0
            ;;
        -*)
            echo "Unknown option: $1" >&2
            exit 3
            ;;
        *)
            KIT_DIR="$1"
            shift
            ;;
    esac
done

# Default to parent directory if not specified
if [[ -z "$KIT_DIR" ]]; then
    KIT_DIR="${SCRIPT_DIR}/.."
fi

# Resolve to absolute path
KIT_DIR="$(cd "$KIT_DIR" && pwd)"

echo "Validating kit at: $KIT_DIR"

ERRORS=0

# Helper functions
check_file() {
    local file="$1"
    local required="${2:-true}"
    local path="$KIT_DIR/$file"

    if [[ -f "$path" ]]; then
        echo "  [OK] $file"
        return 0
    elif [[ "$required" == "true" ]]; then
        echo "  [MISSING] $file (required)" >&2
        ERRORS=$((ERRORS + 1))
        return 1
    else
        echo "  [SKIP] $file (optional)"
        return 0
    fi
}

check_dir() {
    local dir="$1"
    local required="${2:-true}"
    local path="$KIT_DIR/$dir"

    if [[ -d "$path" ]]; then
        echo "  [OK] $dir/"
        return 0
    elif [[ "$required" == "true" ]]; then
        echo "  [MISSING] $dir/ (required)" >&2
        ERRORS=$((ERRORS + 1))
        return 1
    else
        echo "  [SKIP] $dir/ (optional)"
        return 0
    fi
}

validate_json() {
    local file="$1"
    local path="$KIT_DIR/$file"

    if [[ ! -f "$path" ]]; then
        return 0  # Skip if file doesn't exist (handled by check_file)
    fi

    if command -v python3 >/dev/null 2>&1; then
        if python3 -c "import json; json.load(open('$path'))" 2>/dev/null; then
            echo "  [VALID JSON] $file"
            return 0
        else
            echo "  [INVALID JSON] $file" >&2
            ERRORS=$((ERRORS + 1))
            return 1
        fi
    elif command -v jq >/dev/null 2>&1; then
        if jq empty "$path" 2>/dev/null; then
            echo "  [VALID JSON] $file"
            return 0
        else
            echo "  [INVALID JSON] $file" >&2
            ERRORS=$((ERRORS + 1))
            return 1
        fi
    else
        echo "  [SKIP] $file (no JSON validator available)"
        return 0
    fi
}

validate_ndjson() {
    local file="$1"
    local path="$KIT_DIR/$file"

    if [[ ! -f "$path" ]]; then
        return 0  # Skip if file doesn't exist
    fi

    if command -v python3 >/dev/null 2>&1; then
        local result
        result=$(python3 -c "
import json, sys
path = '$path'
errors = 0
with open(path, 'r') as f:
    for i, line in enumerate(f, 1):
        line = line.strip()
        if not line:
            continue
        try:
            json.loads(line)
        except json.JSONDecodeError as e:
            print(f'Line {i}: {e}', file=sys.stderr)
            errors += 1
            if errors >= 5:
                print('(truncated after 5 errors)', file=sys.stderr)
                break
sys.exit(0 if errors == 0 else 1)
" 2>&1)
        if [[ $? -eq 0 ]]; then
            echo "  [VALID NDJSON] $file"
            return 0
        else
            echo "  [INVALID NDJSON] $file" >&2
            echo "$result" >&2
            ERRORS=$((ERRORS + 1))
            return 1
        fi
    else
        echo "  [SKIP] $file (python3 required for NDJSON validation)"
        return 0
    fi
}

# =============================================================================
# Directory Structure Validation
# =============================================================================
echo ""
echo "=== Checking directory structure ==="
check_dir "schemas"
check_dir "exports"
check_dir "kit"

# =============================================================================
# Core Files Validation
# =============================================================================
echo ""
echo "=== Checking core files ==="
check_file "thresholds.yaml"
check_file "thresholds.yaml.dsse"
check_file "SHA256SUMS"

# =============================================================================
# Schema Files Validation
# =============================================================================
echo ""
echo "=== Checking schema files ==="
check_file "schemas/observer_event.schema.json"
check_file "schemas/observer_event.schema.json.dsse"
check_file "schemas/webhook_admission.schema.json"
check_file "schemas/webhook_admission.schema.json.dsse"

# =============================================================================
# Kit Files Validation
# =============================================================================
echo ""
echo "=== Checking kit files ==="
check_file "kit/ed25519.pub"
check_file "kit/verify.sh"
check_file "kit/zastava-kit.tzst" false  # Optional - may not be in source tree
check_file "kit/zastava-kit.tzst.dsse" false

# =============================================================================
# Export Files Validation
# =============================================================================
echo ""
echo "=== Checking export files ==="

if [[ "$COMBINED_FORMAT" == "true" ]]; then
    # Combined format
    echo "(Combined format mode)"
    check_file "exports/combined.runtime.ndjson"
    check_file "exports/combined.runtime.ndjson.dsse"
    # Legacy files are optional in combined mode
    check_file "exports/observer_events.ndjson" false
    check_file "exports/webhook_admissions.ndjson" false
else
    # Legacy format
    echo "(Legacy format mode)"
    check_file "exports/observer_events.ndjson"
    check_file "exports/observer_events.ndjson.dsse"
    check_file "exports/webhook_admissions.ndjson"
    check_file "exports/webhook_admissions.ndjson.dsse"
    # Combined is optional in legacy mode
    check_file "exports/combined.runtime.ndjson" false
fi

# =============================================================================
# JSON/NDJSON Format Validation
# =============================================================================
echo ""
echo "=== Validating file formats ==="

validate_json "schemas/observer_event.schema.json"
validate_json "schemas/webhook_admission.schema.json"

if [[ "$COMBINED_FORMAT" == "true" ]] && [[ -f "$KIT_DIR/exports/combined.runtime.ndjson" ]]; then
    validate_ndjson "exports/combined.runtime.ndjson"
else
    if [[ -f "$KIT_DIR/exports/observer_events.ndjson" ]]; then
        validate_ndjson "exports/observer_events.ndjson"
    fi
    if [[ -f "$KIT_DIR/exports/webhook_admissions.ndjson" ]]; then
        validate_ndjson "exports/webhook_admissions.ndjson"
    fi
fi

# =============================================================================
# Combined Format Structure Validation
# =============================================================================
if [[ "$COMBINED_FORMAT" == "true" ]] && [[ -f "$KIT_DIR/exports/combined.runtime.ndjson" ]]; then
    echo ""
    echo "=== Validating combined format structure ==="

    if command -v python3 >/dev/null 2>&1; then
        python3 - "$KIT_DIR/exports/combined.runtime.ndjson" <<'PYTHON'
import json
import sys

path = sys.argv[1]
errors = []
has_header = False
has_footer = False
record_types = set()

with open(path, 'r') as f:
    for i, line in enumerate(f, 1):
        line = line.strip()
        if not line:
            continue
        try:
            record = json.loads(line)
            rtype = record.get("type", "unknown")
            record_types.add(rtype)

            if rtype == "combined.header":
                if has_header:
                    errors.append(f"Line {i}: duplicate header")
                has_header = True
                if i != 1:
                    errors.append(f"Line {i}: header should be first record")
            elif rtype == "combined.footer":
                has_footer = True
        except json.JSONDecodeError as e:
            errors.append(f"Line {i}: {e}")

if not has_header:
    errors.append("Missing combined.header record")
if not has_footer:
    errors.append("Missing combined.footer record")

if errors:
    for e in errors:
        print(f"  [ERROR] {e}", file=sys.stderr)
    sys.exit(1)

print(f"  [OK] Header and footer present")
print(f"  [OK] Record types: {', '.join(sorted(record_types))}")
PYTHON
        if [[ $? -ne 0 ]]; then
            ERRORS=$((ERRORS + 1))
        fi
    fi
fi

# =============================================================================
# Summary
# =============================================================================
echo ""
echo "=== Validation Summary ==="

if [[ $ERRORS -eq 0 ]]; then
    echo "All validations passed!"
    exit 0
else
    echo "$ERRORS validation error(s) found" >&2
    exit 1
fi