#!/bin/bash

# Comprehensive Plex Backup System Test Suite
# This script provides automated testing for all backup-related functionality

set -e

# Color codes for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
CYAN='\033[0;36m'
NC='\033[0m' # No Color

# Test configuration
SCRIPT_DIR="$(dirname "$(readlink -f "$0")")"
TEST_DIR="/tmp/plex-backup-test-$(date +%s)"
TEST_BACKUP_ROOT="$TEST_DIR/backups"
TEST_LOG_ROOT="$TEST_DIR/logs"
TEST_RESULTS_FILE="$TEST_DIR/test-results.json"

# Test counters
TESTS_RUN=0
TESTS_PASSED=0
TESTS_FAILED=0
declare -a FAILED_TESTS=()

# Logging functions
log_test() {
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${CYAN}[TEST ${timestamp}]${NC} $1"
}

log_pass() {
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${GREEN}[PASS ${timestamp}]${NC} $1"
    TESTS_PASSED=$((TESTS_PASSED + 1))
}

log_fail() {
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${RED}[FAIL ${timestamp}]${NC} $1"
    TESTS_FAILED=$((TESTS_FAILED + 1))
    FAILED_TESTS+=("$1")
}

log_info() {
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${BLUE}[INFO ${timestamp}]${NC} $1"
}

log_warn() {
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    echo -e "${YELLOW}[WARN ${timestamp}]${NC} $1"
}

# Test framework functions
run_test() {
    local test_name="$1"
    local test_function="$2"
    
    TESTS_RUN=$((TESTS_RUN + 1))
    log_test "Running: $test_name"
    
    if $test_function; then
        log_pass "$test_name"
        record_test_result "$test_name" "PASS" ""
    else
        log_fail "$test_name"
        record_test_result "$test_name" "FAIL" "Test function returned non-zero exit code"
    fi
}

record_test_result() {
    local test_name="$1"
    local status="$2"
    local error_message="$3"
    local timestamp=$(date -Iseconds)
    
    # Initialize results file if it doesn't exist
    if [ ! -f "$TEST_RESULTS_FILE" ]; then
        echo "[]" > "$TEST_RESULTS_FILE"
    fi
    
    local result=$(jq -n \
        --arg test_name "$test_name" \
        --arg status "$status" \
        --arg error_message "$error_message" \
        --arg timestamp "$timestamp" \
        '{
            test_name: $test_name,
            status: $status,
            error_message: $error_message,
            timestamp: $timestamp
        }')
    
    jq --argjson result "$result" '. += [$result]' "$TEST_RESULTS_FILE" > "${TEST_RESULTS_FILE}.tmp" && \
    mv "${TEST_RESULTS_FILE}.tmp" "$TEST_RESULTS_FILE"
}

# Setup test environment
setup_test_environment() {
    log_info "Setting up test environment in $TEST_DIR"
    
    # Create test directories
    mkdir -p "$TEST_DIR"
    mkdir -p "$TEST_BACKUP_ROOT"
    mkdir -p "$TEST_LOG_ROOT"
    mkdir -p "$TEST_DIR/mock_plex"
    
    # Create mock Plex files for testing
    echo "PRAGMA user_version=1;" > "$TEST_DIR/mock_plex/com.plexapp.plugins.library.db"
    echo "PRAGMA user_version=1;" > "$TEST_DIR/mock_plex/com.plexapp.plugins.library.blobs.db"
    dd if=/dev/zero of="$TEST_DIR/mock_plex/Preferences.xml" bs=1024 count=1 2>/dev/null
    
    # Create mock performance log
    echo "[]" > "$TEST_DIR/mock-performance.json"
    echo "{}" > "$TEST_DIR/mock-backup.json"
    
    log_info "Test environment setup complete"
}

# Cleanup test environment
cleanup_test_environment() {
    if [ -d "$TEST_DIR" ]; then
        log_info "Cleaning up test environment"
        rm -rf "$TEST_DIR"
    fi
}

# Mock functions to replace actual backup script functions
mock_manage_plex_service() {
    local action="$1"
    echo "Mock: Plex service $action"
    return 0
}

mock_calculate_checksum() {
    local file="$1"
    echo "$(echo "$file" | md5sum | cut -d' ' -f1)"
    return 0
}

mock_verify_backup() {
    local src="$1"
    local dest="$2"
    # Always return success for testing
    return 0
}

# Test: JSON log initialization
test_json_log_initialization() {
    local test_log="$TEST_DIR/test-init.json"
    
    # Remove file if it exists
    rm -f "$test_log"
    
    # Test initialization
    if [ ! -f "$test_log" ] || ! jq empty "$test_log" 2>/dev/null; then
        echo "{}" > "$test_log"
    fi
    
    # Verify file exists and is valid JSON
    if [ -f "$test_log" ] && jq empty "$test_log" 2>/dev/null; then
        return 0
    else
        return 1
    fi
}

# Test: Performance tracking
test_performance_tracking() {
    local test_perf_log="$TEST_DIR/test-performance.json"
    echo "[]" > "$test_perf_log"
    
    # Mock performance tracking function
    track_performance_test() {
        local operation="$1"
        local start_time="$2"
        local end_time=$(date +%s)
        local duration=$((end_time - start_time))
        
        local entry=$(jq -n \
            --arg operation "$operation" \
            --arg duration "$duration" \
            --arg timestamp "$(date -Iseconds)" \
            '{
                operation: $operation,
                duration_seconds: ($duration | tonumber),
                timestamp: $timestamp
            }')
        
        jq --argjson entry "$entry" '. += [$entry]' "$test_perf_log" > "${test_perf_log}.tmp" && \
        mv "${test_perf_log}.tmp" "$test_perf_log"
    }
    
    # Test tracking
    local start_time=$(date +%s)
    sleep 1  # Simulate work
    track_performance_test "test_operation" "$start_time"
    
    # Verify entry was added
    local entry_count=$(jq length "$test_perf_log")
    if [ "$entry_count" -eq 1 ]; then
        return 0
    else
        return 1
    fi
}

# Test: Notification system
test_notification_system() {
    # Mock notification function
    send_notification_test() {
        local title="$1"
        local message="$2"
        local status="${3:-info}"
        
        # Just verify parameters are received correctly
        if [ -n "$title" ] && [ -n "$message" ]; then
            echo "Notification: $title - $message ($status)" > "$TEST_DIR/notification.log"
            return 0
        else
            return 1
        fi
    }
    
    # Test notification
    send_notification_test "Test Title" "Test Message" "success"
    
    # Verify notification was processed
    if [ -f "$TEST_DIR/notification.log" ] && grep -q "Test Title" "$TEST_DIR/notification.log"; then
        return 0
    else
        return 1
    fi
}

# Test: Checksum caching
test_checksum_caching() {
    local test_file="$TEST_DIR/checksum_test.txt"
    local cache_file="${test_file}.md5"
    
    # Create test file
    echo "test content" > "$test_file"
    
    # Mock checksum function with caching
    calculate_checksum_test() {
        local file="$1"
        local cache_file="${file}.md5"
        local file_mtime=$(stat -c %Y "$file" 2>/dev/null || echo "0")
        
        # Check cache
        if [ -f "$cache_file" ]; then
            local cache_mtime=$(stat -c %Y "$cache_file" 2>/dev/null || echo "0")
            if [ "$cache_mtime" -gt "$file_mtime" ]; then
                cat "$cache_file"
                return 0
            fi
        fi
        
        # Calculate and cache
        local checksum=$(md5sum "$file" | cut -d' ' -f1)
        echo "$checksum" > "$cache_file"
        echo "$checksum"
    }
    
    # First calculation (should create cache)
    local checksum1=$(calculate_checksum_test "$test_file")
    
    # Second calculation (should use cache)
    local checksum2=$(calculate_checksum_test "$test_file")
    
    # Verify checksums match and cache file exists
    if [ "$checksum1" = "$checksum2" ] && [ -f "$cache_file" ]; then
        return 0
    else
        return 1
    fi
}

# Test: Backup verification
test_backup_verification() {
    local src_file="$TEST_DIR/source.txt"
    local dest_file="$TEST_DIR/backup.txt"
    
    # Create identical files
    echo "backup test content" > "$src_file"
    cp "$src_file" "$dest_file"
    
    # Mock verification function
    verify_backup_test() {
        local src="$1"
        local dest="$2"
        
        local src_checksum=$(md5sum "$src" | cut -d' ' -f1)
        local dest_checksum=$(md5sum "$dest" | cut -d' ' -f1)
        
        if [ "$src_checksum" = "$dest_checksum" ]; then
            return 0
        else
            return 1
        fi
    }
    
    # Test verification
    if verify_backup_test "$src_file" "$dest_file"; then
        return 0
    else
        return 1
    fi
}

# Test: Parallel processing framework
test_parallel_processing() {
    local temp_dir=$(mktemp -d)
    local -a pids=()
    local total_jobs=5
    local completed_jobs=0
    
    # Simulate parallel jobs
    for i in $(seq 1 $total_jobs); do
        (
            # Simulate work
            sleep 0.$i
            echo "$i" > "$temp_dir/job_$i.result"
        ) &
        pids+=($!)
    done
    
    # Wait for all jobs
    for pid in "${pids[@]}"; do
        if wait "$pid"; then
            completed_jobs=$((completed_jobs + 1))
        fi
    done
    
    # Verify all jobs completed
    local result_files=$(find "$temp_dir" -name "job_*.result" | wc -l)
    
    # Cleanup
    rm -rf "$temp_dir"
    
    if [ "$completed_jobs" -eq "$total_jobs" ] && [ "$result_files" -eq "$total_jobs" ]; then
        return 0
    else
        return 1
    fi
}

# Test: Database integrity check simulation
test_database_integrity() {
    local test_db="$TEST_DIR/test.db"
    
    # Create a simple SQLite database
    sqlite3 "$test_db" "CREATE TABLE test (id INTEGER, name TEXT);"
    sqlite3 "$test_db" "INSERT INTO test VALUES (1, 'test');"
    
    # Mock integrity check
    check_integrity_test() {
        local db_file="$1"
        
        # Use sqlite3 instead of Plex SQLite for testing
        local result=$(sqlite3 "$db_file" "PRAGMA integrity_check;" 2>/dev/null)
        
        if echo "$result" | grep -q "ok"; then
            return 0
        else
            return 1
        fi
    }
    
    # Test integrity check
    if check_integrity_test "$test_db"; then
        return 0
    else
        return 1
    fi
}

# Test: Configuration parsing
test_configuration_parsing() {
    # Mock command line parsing
    parse_args_test() {
        local args=("$@")
        local auto_repair=false
        local parallel=true
        local webhook=""
        
        for arg in "${args[@]}"; do
            case "$arg" in
                --auto-repair) auto_repair=true ;;
                --no-parallel) parallel=false ;;
                --webhook=*) webhook="${arg#*=}" ;;
            esac
        done
        
        # Return parsed values
        echo "$auto_repair $parallel $webhook"
    }
    
    # Test parsing
    local result=$(parse_args_test --auto-repair --webhook=http://example.com)
    
    if echo "$result" | grep -q "true true http://example.com"; then
        return 0
    else
        return 1
    fi
}

# Test: Error handling
test_error_handling() {
    # Mock function that can fail
    test_function_with_error() {
        local should_fail="$1"
        
        if [ "$should_fail" = "true" ]; then
            return 1
        else
            return 0
        fi
    }
    
    # Test success case
    if test_function_with_error "false"; then
        # Test failure case
        if ! test_function_with_error "true"; then
            return 0  # Both cases worked as expected
        fi
    fi
    
    return 1
}

# Run all unit tests
run_all_tests() {
    log_info "Setting up test environment"
    setup_test_environment
    
    log_info "Starting unit tests"
    
    # Core functionality tests
    run_test "JSON Log Initialization" test_json_log_initialization
    run_test "Performance Tracking" test_performance_tracking
    run_test "Notification System" test_notification_system
    run_test "Checksum Caching" test_checksum_caching
    run_test "Backup Verification" test_backup_verification
    run_test "Parallel Processing" test_parallel_processing
    run_test "Database Integrity Check" test_database_integrity
    run_test "Configuration Parsing" test_configuration_parsing
    run_test "Error Handling" test_error_handling
    
    log_info "Unit tests completed"
}

# Run integration tests (requires actual Plex environment)
run_integration_tests() {
    log_info "Starting integration tests"
    log_warn "Integration tests require a working Plex installation"
    
    # Check if Plex service exists
    if ! systemctl list-units --all | grep -q plexmediaserver; then
        log_warn "Plex service not found - skipping integration tests"
        return 0
    fi
    
    # Test actual service management (if safe to do so)
    log_info "Integration tests would test actual Plex service management"
    log_info "Skipping for safety - implement with caution"
}

# Run performance tests
run_performance_tests() {
    log_info "Starting performance benchmarks"
    
    local start_time=$(date +%s)
    
    # Test file operations
    local test_file="$TEST_DIR/perf_test.dat"
    dd if=/dev/zero of="$test_file" bs=1M count=10 2>/dev/null
    
    # Benchmark checksum calculation
    local checksum_start=$(date +%s)
    md5sum "$test_file" > /dev/null
    local checksum_time=$(($(date +%s) - checksum_start))
    
    # Benchmark compression
    local compress_start=$(date +%s)
    tar -czf "$TEST_DIR/perf_test.tar.gz" -C "$TEST_DIR" "perf_test.dat"
    local compress_time=$(($(date +%s) - compress_start))
    
    local total_time=$(($(date +%s) - start_time))
    
    log_info "Performance Results:"
    log_info "  Checksum (10MB): ${checksum_time}s"
    log_info "  Compression (10MB): ${compress_time}s"
    log_info "  Total benchmark time: ${total_time}s"
    
    # Record performance data
    local perf_entry=$(jq -n \
        --arg checksum_time "$checksum_time" \
        --arg compress_time "$compress_time" \
        --arg total_time "$total_time" \
        --arg timestamp "$(date -Iseconds)" \
        '{
            benchmark: "performance_test",
            checksum_time_seconds: ($checksum_time | tonumber),
            compress_time_seconds: ($compress_time | tonumber),
            total_time_seconds: ($total_time | tonumber),
            timestamp: $timestamp
        }')
    
    echo "$perf_entry" > "$TEST_DIR/performance_results.json"
}

# Generate comprehensive test report
generate_test_report() {
    local timestamp=$(date '+%Y-%m-%d %H:%M:%S')
    
    echo
    echo "=============================================="
    echo "           PLEX BACKUP TEST REPORT"
    echo "=============================================="
    echo "Test Run: $timestamp"
    echo "Tests Run: $TESTS_RUN"
    echo "Tests Passed: $TESTS_PASSED"
    echo "Tests Failed: $TESTS_FAILED"
    echo
    
    if [ $TESTS_FAILED -gt 0 ]; then
        echo "FAILED TESTS:"
        for failed_test in "${FAILED_TESTS[@]}"; do
            echo "  - $failed_test"
        done
        echo
    fi
    
    local success_rate=0
    if [ $TESTS_RUN -gt 0 ]; then
        success_rate=$(( (TESTS_PASSED * 100) / TESTS_RUN ))
    fi
    
    echo "Success Rate: ${success_rate}%"
    echo
    
    if [ $TESTS_FAILED -eq 0 ]; then
        log_pass "All tests passed successfully!"
    else
        log_fail "Some tests failed - review output above"
    fi
    
    # Save detailed results
    if [ -f "$TEST_RESULTS_FILE" ]; then
        local report_file="$TEST_DIR/test_report_$(date +%Y%m%d_%H%M%S).json"
        jq -n \
            --arg timestamp "$timestamp" \
            --arg tests_run "$TESTS_RUN" \
            --arg tests_passed "$TESTS_PASSED" \
            --arg tests_failed "$TESTS_FAILED" \
            --arg success_rate "$success_rate" \
            --argjson failed_tests "$(printf '%s\n' "${FAILED_TESTS[@]}" | jq -R . | jq -s .)" \
            --argjson test_details "$(cat "$TEST_RESULTS_FILE")" \
            '{
                test_run_timestamp: $timestamp,
                summary: {
                    tests_run: ($tests_run | tonumber),
                    tests_passed: ($tests_passed | tonumber),
                    tests_failed: ($tests_failed | tonumber),
                    success_rate_percent: ($success_rate | tonumber)
                },
                failed_tests: $failed_tests,
                detailed_results: $test_details
            }' > "$report_file"
        
        log_info "Detailed test report saved to: $report_file"
    fi
}

# Integration tests (if requested)
run_integration_tests() {
    log_info "Running integration tests..."
    
    # Note: These would require actual Plex installation
    # For now, we'll just indicate what would be tested
    
    log_warn "Integration tests require running Plex Media Server"
    log_warn "These tests would cover:"
    log_warn "  - Service stop/start functionality"
    log_warn "  - Database integrity checks"
    log_warn "  - Full backup and restore cycles"
    log_warn "  - Performance under load"
}

# Performance benchmarks
run_performance_tests() {
    log_info "Running performance benchmarks..."
    
    local start_time=$(date +%s)
    
    # Create large test files
    local large_file="$TEST_DIR/large_test.db"
    dd if=/dev/zero of="$large_file" bs=1M count=100 2>/dev/null
    
    # Benchmark checksum calculation
    local checksum_start=$(date +%s)
    md5sum "$large_file" > /dev/null
    local checksum_end=$(date +%s)
    local checksum_time=$((checksum_end - checksum_start))
    
    # Benchmark compression
    local compress_start=$(date +%s)
    tar -czf "$TEST_DIR/large_test.tar.gz" -C "$TEST_DIR" "large_test.db"
    local compress_end=$(date +%s)
    local compress_time=$((compress_end - compress_start))
    
    local total_time=$(($(date +%s) - start_time))
    
    log_info "Performance Results:"
    log_info "  Checksum (100MB): ${checksum_time}s"
    log_info "  Compression (100MB): ${compress_time}s"
    log_info "  Total benchmark time: ${total_time}s"
}

# Main execution
main() {
    case "${1:-all}" in
        "unit")
            run_all_tests
            ;;
        "integration")
            run_integration_tests
            ;;
        "performance")
            run_performance_tests
            ;;
        "all")
            run_all_tests
            # Uncomment for integration tests if environment supports it
            # run_integration_tests
            run_performance_tests
            ;;
        *)
            echo "Usage: $0 [unit|integration|performance|all]"
            echo "  unit        - Run unit tests only"
            echo "  integration - Run integration tests (requires Plex)"
            echo "  performance - Run performance benchmarks"
            echo "  all         - Run all available tests"
            exit 1
            ;;
    esac
    
    generate_test_report
    
    # Exit with appropriate code
    if [ $TESTS_FAILED -gt 0 ]; then
        exit 1
    else
        exit 0
    fi
}

# Trap to ensure cleanup on exit
trap cleanup_test_environment EXIT

main "$@"