#!/bin/bash

# Test Validation Script
# Checks TDD compliance, test coverage, and test execution

set -e

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

# Configuration
PROJECT_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
TASK_ID=""

# Help function
show_help() {
    echo "Usage: $0 <task-id>"
    echo ""
    echo "Validates test compliance for a specific task:"
    echo "  - TDD compliance (tests written before code)"
    echo "  - Test coverage and execution"
    echo "  - Test file organization"
    echo ""
    echo "Examples:"
    echo "  $0 15              # Validate task 15"
}

# Parse arguments
while [[ $# -gt 0 ]]; do
    case $1 in
        --help)
            show_help
            exit 0
            ;;
        -*)
            echo -e "${RED}Error: Unknown option $1${NC}"
            show_help
            exit 1
            ;;
        *)
            if [[ -z "$TASK_ID" ]]; then
                TASK_ID="$1"
            else
                echo -e "${RED}Error: Multiple task IDs specified${NC}"
                exit 1
            fi
            shift
            ;;
    esac
done

# Validate task ID
if [[ -z "$TASK_ID" ]]; then
    echo -e "${RED}Error: Task ID is required${NC}"
    show_help
    exit 1
fi

# Function to check if a file is a test file
is_test_file() {
    local file="$1"
    [[ "$file" == *"test"* ]] && [[ "$file" == *.py ]]
}

# Function to check if a file is source code
is_source_file() {
    local file="$1"
    [[ "$file" == *.py ]] && [[ "$file" != *"__init__.py" ]] && [[ "$file" != *"test"* ]]
}

# Function to analyze test coverage for a specific task
analyze_task_test_coverage() {
    local task_id="$1"
    local test_files=()
    local source_files=()
    local coverage_issues=()
    
    echo -e "${BLUE}📊 Test Coverage Analysis for Task $task_id:${NC}"
    
    # Find test files
    while IFS= read -r -d '' file; do
        if is_test_file "$file"; then
            test_files+=("$file")
        fi
    done < <(find "$PROJECT_ROOT/tests" -name "*.py" -print0)
    
    # Find source files
    while IFS= read -r -d '' file; do
        if is_source_file "$file"; then
            source_files+=("$file")
        fi
    done < <(find "$PROJECT_ROOT/src" -name "*.py" -print0)
    
    echo -e "  ${BLUE}• Test files found:${NC} ${#test_files[@]}"
    echo -e "  ${BLUE}• Source files found:${NC} ${#source_files[@]}"
    
    # Check if we have tests
    if [[ ${#test_files[@]} -eq 0 ]]; then
        echo -e "  ${RED}❌ No test files found in tests/ directory${NC}"
        coverage_issues+=("no_tests")
        return 1
    fi
    
    # Check test file organization
    echo -e "${BLUE}📁 Test File Organization:${NC}"
    for test_file in "${test_files[@]}"; do
        local relative_path="${test_file#$PROJECT_ROOT/}"
        echo -e "  ${GREEN}✅ $relative_path${NC}"
    done
    
    # Check if tests are passing
    echo -e "${BLUE}🧪 Test Execution Status:${NC}"
    if command -v pytest >/dev/null 2>&1; then
        echo -e "  ${BLUE}Running tests...${NC}"
        if cd "$PROJECT_ROOT" && python -m pytest --tb=short -q; then
            echo -e "  ${GREEN}✅ All tests passing${NC}"
        else
            echo -e "  ${RED}❌ Some tests are failing${NC}"
            coverage_issues+=("tests_failing")
            return 1
        fi
    else
        echo -e "  ${YELLOW}⚠️  pytest not available - skipping test execution${NC}"
        coverage_issues+=("pytest_unavailable")
    fi
    
    return 0
}

# Function to check TDD compliance
check_tdd_compliance() {
    local task_id="$1"
    
    echo -e "${BLUE}🔄 TDD Compliance Check:${NC}"
    
    # Check if tests exist before implementation
    local test_files_count=$(find "$PROJECT_ROOT/tests" -name "*.py" | wc -l)
    local source_files_count=$(find "$PROJECT_ROOT/src" -name "*.py" | wc -l)
    
    if [[ $test_files_count -eq 0 ]]; then
        echo -e "  ${RED}❌ No test files found - violates TDD principle${NC}"
        echo -e "  ${YELLOW}  TDD requires tests to be written before implementation${NC}"
        return 1
    fi
    
    # Check test file naming conventions
    local test_naming_issues=0
    while IFS= read -r -d '' file; do
        local filename=$(basename "$file")
        if [[ ! "$filename" =~ ^test_.*\.py$ ]] && [[ ! "$filename" =~ ^.*_test\.py$ ]]; then
            echo -e "  ${YELLOW}⚠️  Test file naming: $filename (should start with 'test_' or end with '_test.py')${NC}"
            test_naming_issues=$((test_naming_issues + 1))
        fi
    done < <(find "$PROJECT_ROOT/tests" -name "*.py" -print0)
    
    if [[ $test_naming_issues -eq 0 ]]; then
        echo -e "  ${GREEN}✅ Test file naming conventions followed${NC}"
    fi
    
    # Check for test imports and structure
    local test_structure_issues=0
    while IFS= read -r -d '' file; do
        if ! grep -q "import.*test\|from.*test\|pytest\|unittest" "$file" 2>/dev/null; then
            echo -e "  ${YELLOW}⚠️  Test file structure: $file (missing test framework imports)${NC}"
            test_structure_issues=$((test_structure_issues + 1))
        fi
    done < <(find "$PROJECT_ROOT/tests" -name "*.py" -print0)
    
    if [[ $test_structure_issues -eq 0 ]]; then
        echo -e "  ${GREEN}✅ Test file structure looks good${NC}"
    fi
    
    echo -e "  ${GREEN}✅ TDD compliance check passed${NC}"
    return 0
}

# Function to provide test improvement recommendations
suggest_test_improvements() {
    local task_id="$1"
    
    echo -e "${BLUE}💡 Test Improvement Recommendations:${NC}"
    
    # Check for common test patterns
    local test_files=()
    while IFS= read -r -d '' file; do
        if is_test_file "$file"; then
            test_files+=("$file")
        fi
    done < <(find "$PROJECT_ROOT/tests" -name "*.py" -print0)
    
    if [[ ${#test_files[@]} -eq 0 ]]; then
        echo -e "  ${YELLOW}• Create test files for all source modules${NC}"
        echo -e "  ${YELLOW}• Start with basic functionality tests${NC}"
        echo -e "  ${YELLOW}• Use pytest for modern Python testing${NC}"
        return
    fi
    
    # Analyze test patterns
    for test_file in "${test_files[@]}"; do
        local test_functions=$(grep -c "^def test_" "$test_file" 2>/dev/null || echo 0)
        local test_classes=$(grep -c "^class Test" "$test_file" 2>/dev/null || echo 0)
        
        if [[ $test_functions -eq 0 ]] && [[ $test_classes -eq 0 ]]; then
            echo -e "  ${YELLOW}• Add test functions to $test_file${NC}"
        fi
        
        # Check for edge case coverage
        if ! grep -q "test.*error\|test.*exception\|test.*edge\|test.*boundary" "$test_file" 2>/dev/null; then
            echo -e "  ${YELLOW}• Consider adding edge case tests to $test_file${NC}"
        fi
    done
    
    # General recommendations
    echo -e "  ${YELLOW}• Ensure tests cover both success and failure scenarios${NC}"
    echo -e "  ${YELLOW}• Use descriptive test names that explain the scenario${NC}"
    echo -e "  ${YELLOW}• Mock external dependencies to isolate unit tests${NC}"
    echo -e "  ${YELLOW}• Aim for high test coverage (80%+)${NC}"
}

# Main function
main() {
    local exit_code=0
    local tdd_compliance=0
    local test_coverage=0
    
    echo -e "${BLUE}🧪 Test Validation for Task $TASK_ID${NC}"
    echo -e "${BLUE}Focus: TDD compliance, test coverage, and execution${NC}"
    echo ""
    
    # Check TDD compliance
    if ! check_tdd_compliance "$TASK_ID"; then
        exit_code=1
        tdd_compliance=1
    fi
    echo ""
    
    # Analyze test coverage
    if ! analyze_task_test_coverage "$TASK_ID"; then
        exit_code=1
        test_coverage=1
    fi
    echo ""
    
    # Provide improvement recommendations
    suggest_test_improvements "$TASK_ID"
    echo ""
    
    # Summary
    echo -e "${BLUE}📋 Test Validation Summary:${NC}"
    if [[ $tdd_compliance -eq 0 ]]; then
        echo -e "  ${GREEN}✅ TDD compliance: PASSED${NC}"
    else
        echo -e "  ${RED}❌ TDD compliance: FAILED${NC}"
    fi
    
    if [[ $test_coverage -eq 0 ]]; then
        echo -e "  ${GREEN}✅ Test coverage: PASSED${NC}"
    else
        echo -e "  ${RED}❌ Test coverage: FAILED${NC}"
    fi
    
    if [[ $exit_code -eq 0 ]]; then
        echo ""
        echo -e "${GREEN}🎉 All test validation checks passed!${NC}"
        echo -e "${GREEN}✅ Task $TASK_ID meets test quality standards${NC}"
    else
        echo ""
        echo -e "${RED}🚫 Test validation failed - must be resolved before task completion${NC}"
        echo -e "${YELLOW}  Fix all test issues before proceeding${NC}"
    fi
    
    echo ""
    echo -e "${BLUE}🔧 Quick Fix Commands:${NC}"
    echo -e "  ${BLUE}• Run tests:${NC} uv run pytest"
    echo -e "  ${BLUE}• Run with coverage:${NC} uv run pytest --cov=src"
    echo -e "  ${BLUE}• Re-validate:${NC} $0 $TASK_ID"
    
    exit $exit_code
}

# Run main function
main "$@"