package main

import (
	"regexp"
	"strings"
	"testing"
)

// Helper function to normalize whitespace for comparison
func normalizeWhitespace(s string) string {
	// Replace all whitespace with a single space
	re := regexp.MustCompile(`\s+`)
	return re.ReplaceAllString(strings.TrimSpace(s), " ")
}

func TestSimpleValueMultiplication(t *testing.T) {
	fileContents := `
		<config>
			<item>
				<value>100</value>
			</item>
		</config>
	`
	expected := `
		<config>
			<item>
				<value>150</value>
			</item>
		</config>
	`

	// Create a regex pattern with the (?s) flag for multiline matching
	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>`)
	luaExpr := `*1.5`
	luaScript := buildLuaScript(luaExpr)

	modifiedContent, err := process(fileContents, regex, luaScript)
	if err != nil {
		t.Fatalf("Error processing file: %v", err)
	}

	// Compare normalized content
	normalizedModified := normalizeWhitespace(modifiedContent)
	normalizedExpected := normalizeWhitespace(expected)
	if normalizedModified != normalizedExpected {
		t.Fatalf("Expected modified content to be %q, but got %q", normalizedExpected, normalizedModified)
	}
}

func TestShorthandNotation(t *testing.T) {
	fileContents := `
		<config>
			<item>
				<value>100</value>
			</item>
		</config>
	`
	expected := `
		<config>
			<item>
				<value>150</value>
			</item>
		</config>
	`

	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>`)
	luaExpr := `v1 * 1.5`
	luaScript := buildLuaScript(luaExpr)

	modifiedContent, err := process(fileContents, regex, luaScript)
	if err != nil {
		t.Fatalf("Error processing file: %v", err)
	}

	normalizedModified := normalizeWhitespace(modifiedContent)
	normalizedExpected := normalizeWhitespace(expected)
	if normalizedModified != normalizedExpected {
		t.Fatalf("Expected modified content to be %q, but got %q", normalizedExpected, normalizedModified)
	}
}

func TestArrayNotation(t *testing.T) {
	fileContents := `
		<config>
			<item>
				<value>100</value>
			</item>
		</config>
	`
	expected := `
		<config>
			<item>
				<value>150</value>
			</item>
		</config>
	`

	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>`)
	luaExpr := `v[1] * 1.5`
	luaScript := buildLuaScript(luaExpr)

	modifiedContent, err := process(fileContents, regex, luaScript)
	if err != nil {
		t.Fatalf("Error processing file: %v", err)
	}

	normalizedModified := normalizeWhitespace(modifiedContent)
	normalizedExpected := normalizeWhitespace(expected)
	if normalizedModified != normalizedExpected {
		t.Fatalf("Expected modified content to be %q, but got %q", normalizedExpected, normalizedModified)
	}
}

func TestMultipleMatches(t *testing.T) {
	fileContents := `
		<config>
			<item>
				<value>100</value>
			</item>
			<item>
				<value>200</value>
			</item>
			<item> <value>300</value> </item>
		</config>
	`
	expected := `
		<config>
			<item>
				<value>150</value>
			</item>
			<item>
				<value>300</value>
			</item>
			<item> <value>450</value> </item>
		</config>
	`

	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>`)
	luaExpr := `*1.5`
	luaScript := buildLuaScript(luaExpr)

	modifiedContent, err := process(fileContents, regex, luaScript)
	if err != nil {
		t.Fatalf("Error processing file: %v", err)
	}

	normalizedModified := normalizeWhitespace(modifiedContent)
	normalizedExpected := normalizeWhitespace(expected)
	if normalizedModified != normalizedExpected {
		t.Fatalf("Expected modified content to be %q, but got %q", normalizedExpected, normalizedModified)
	}
}

func TestMultipleCaptureGroups(t *testing.T) {
	fileContents := `
		<config>
			<item>
				<value>10</value>
				<multiplier>5</multiplier>
			</item>
		</config>
	`
	expected := `
		<config>
			<item>
				<value>50</value>
				<multiplier>5</multiplier>
			</item>
		</config>
	`

	// Use (?s) flag to match across multiple lines
	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>.*?<multiplier>(\d+)</multiplier>`)
	luaExpr := `v1 * v2`
	luaScript := buildLuaScript(luaExpr)

	// Verify the regex matches before processing
	matches := regex.FindStringSubmatch(fileContents)
	if len(matches) <= 1 {
		t.Fatalf("Regex didn't match any capture groups in test input: %v", fileContents)
	}
	t.Logf("Matches: %v", matches)

	modifiedContent, err := process(fileContents, regex, luaScript)
	if err != nil {
		t.Fatalf("Error processing file: %v", err)
	}

	normalizedModified := normalizeWhitespace(modifiedContent)
	normalizedExpected := normalizeWhitespace(expected)
	if normalizedModified != normalizedExpected {
		t.Fatalf("Expected modified content to be %q, but got %q", normalizedExpected, normalizedModified)
	}
}

func TestModifyingMultipleValues(t *testing.T) {
	fileContents := `
		<config>
			<item>
				<value>50</value>
				<multiplier>3</multiplier>
				<divider>2</divider>
			</item>
		</config>
	`
	expected := `
		<config>
			<item>
				<value>75</value>
				<multiplier>5</multiplier>
				<divider>1</divider>
			</item>
		</config>
	`

	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>.*?<multiplier>(\d+)</multiplier>.*?<divider>(\d+)</divider>`)
	luaExpr := `v[1] = v[1] * v[2] / v[3]; v[2] = min(v[2] * 2, 5); v[3] = max(1, v[3] / 2)`
	luaScript := buildLuaScript(luaExpr)

	// Verify the regex matches before processing
	matches := regex.FindStringSubmatch(fileContents)
	if len(matches) <= 1 {
		t.Fatalf("Regex didn't match any capture groups in test input: %v", fileContents)
	}
	t.Logf("Matches: %v", matches)

	modifiedContent, err := process(fileContents, regex, luaScript)
	if err != nil {
		t.Fatalf("Error processing file: %v", err)
	}

	normalizedModified := normalizeWhitespace(modifiedContent)
	normalizedExpected := normalizeWhitespace(expected)
	if normalizedModified != normalizedExpected {
		t.Fatalf("Expected modified content to be %q, but got %q", normalizedExpected, normalizedModified)
	}
}

func TestDecimalValues(t *testing.T) {
	fileContents := `
		<config>
			<item>
				<value>10.5</value>
				<multiplier>2.5</multiplier>
			</item>
		</config>
	`
	expected := `
		<config>
			<item>
				<value>26.25</value>
				<multiplier>2.5</multiplier>
			</item>
		</config>
	`

	regex := regexp.MustCompile(`(?s)<value>([0-9.]+)</value>.*?<multiplier>([0-9.]+)</multiplier>`)
	luaExpr := `v1 * v2`
	luaScript := buildLuaScript(luaExpr)

	modifiedContent, err := process(fileContents, regex, luaScript)
	if err != nil {
		t.Fatalf("Error processing file: %v", err)
	}

	normalizedModified := normalizeWhitespace(modifiedContent)
	normalizedExpected := normalizeWhitespace(expected)
	if normalizedModified != normalizedExpected {
		t.Fatalf("Expected modified content to be %q, but got %q", normalizedExpected, normalizedModified)
	}
}

func TestLuaMathFunctions(t *testing.T) {
	fileContents := `
		<config>
			<item>
				<value>16</value>
			</item>
		</config>
	`
	expected := `
		<config>
			<item>
				<value>4</value>
			</item>
		</config>
	`

	regex := regexp.MustCompile(`(?s)<value>(\d+)</value>`)
	luaExpr := `math.sqrt(v1)`
	luaScript := buildLuaScript(luaExpr)

	modifiedContent, err := process(fileContents, regex, luaScript)
	if err != nil {
		t.Fatalf("Error processing file: %v", err)
	}

	normalizedModified := normalizeWhitespace(modifiedContent)
	normalizedExpected := normalizeWhitespace(expected)
	if normalizedModified != normalizedExpected {
		t.Fatalf("Expected modified content to be %q, but got %q", normalizedExpected, normalizedModified)
	}
}