BigChef/processor/processor.go

package processor

import (
	"fmt"
	"io"
	"net/http"
	"strings"

	logger "git.site.quack-lab.dev/dave/cylogger"
	lua "github.com/yuin/gopher-lua"
)

// Maybe we make this an interface again for the shits and giggles
// We will see, it could easily be...

func NewLuaState() (*lua.LState, error) {
	L := lua.NewState()
	// defer L.Close()

	// Load math library
	logger.Debug("Loading Lua math library")
	L.Push(L.GetGlobal("require"))
	L.Push(lua.LString("math"))
	if err := L.PCall(1, 1, nil); err != nil {
		logger.Error("Failed to load Lua math library: %v", err)
		return nil, fmt.Errorf("error loading Lua math library: %v", err)
	}

	// Initialize helper functions
	logger.Debug("Initializing Lua helper functions")
	if err := InitLuaHelpers(L); err != nil {
		logger.Error("Failed to initialize Lua helper functions: %v", err)
		return nil, err
	}

	return L, nil
}

// func Process(filename string, pattern string, luaExpr string) (int, int, error) {
// 	logger.Debug("Processing file %q with pattern %q", filename, pattern)
//
// 	// Read file content
// 	cwd, err := os.Getwd()
// 	if err != nil {
// 		logger.Error("Failed to get current working directory: %v", err)
// 		return 0, 0, fmt.Errorf("error getting current working directory: %v", err)
// 	}
//
// 	fullPath := filepath.Join(cwd, filename)
// 	logger.Trace("Reading file from: %s", fullPath)
//
// 	stat, err := os.Stat(fullPath)
// 	if err != nil {
// 		logger.Error("Failed to stat file %s: %v", fullPath, err)
// 		return 0, 0, fmt.Errorf("error getting file info: %v", err)
// 	}
// 	logger.Debug("File size: %d bytes, modified: %s", stat.Size(), stat.ModTime().Format(time.RFC3339))
//
// 	content, err := os.ReadFile(fullPath)
// 	if err != nil {
// 		logger.Error("Failed to read file %s: %v", fullPath, err)
// 		return 0, 0, fmt.Errorf("error reading file: %v", err)
// 	}
//
// 	fileContent := string(content)
// 	logger.Trace("File read successfully: %d bytes, hash: %x", len(content), md5sum(content))
//
// 	// Detect and log file type
// 	fileType := detectFileType(filename, fileContent)
// 	if fileType != "" {
// 		logger.Debug("Detected file type: %s", fileType)
// 	}
//
// 	// Process the content
// 	logger.Debug("Starting content processing")
// 	modifiedContent, modCount, matchCount, err := ProcessContent(fileContent, pattern, luaExpr)
// 	if err != nil {
// 		logger.Error("Processing error: %v", err)
// 		return 0, 0, err
// 	}
//
// 	logger.Debug("Processing results: %d matches, %d modifications", matchCount, modCount)
//
// 	// If we made modifications, save the file
// 	if modCount > 0 {
// 		// Calculate changes summary
// 		changePercent := float64(len(modifiedContent)) / float64(len(fileContent)) * 100
// 		logger.Info("File size change: %d → %d bytes (%.1f%%)",
// 			len(fileContent), len(modifiedContent), changePercent)
//
// 		logger.Debug("Writing modified content to %s", fullPath)
// 		err = os.WriteFile(fullPath, []byte(modifiedContent), 0644)
// 		if err != nil {
// 			logger.Error("Failed to write to file %s: %v", fullPath, err)
// 			return 0, 0, fmt.Errorf("error writing file: %v", err)
// 		}
// 		logger.Debug("File written successfully, new hash: %x", md5sum([]byte(modifiedContent)))
// 	} else if matchCount > 0 {
// 		logger.Debug("No content modifications needed for %d matches", matchCount)
// 	} else {
// 		logger.Debug("No matches found in file")
// 	}
//
// 	return modCount, matchCount, nil
// }

// FromLua converts a Lua table to a struct or map recursively
func FromLua(L *lua.LState, luaValue lua.LValue) (interface{}, error) {
	switch v := luaValue.(type) {
	// Well shit...
	// Tables in lua are both maps and arrays
	// As arrays they are ordered and as maps, obviously, not
	// So when we parse them to a go map we fuck up the order for arrays
	// We have to find a better way....
	case *lua.LTable:
		isArray, err := IsLuaTableArray(L, v)
		if err != nil {
			return nil, err
		}
		if isArray {
			result := make([]interface{}, 0)
			v.ForEach(func(key lua.LValue, value lua.LValue) {
				converted, _ := FromLua(L, value)
				result = append(result, converted)
			})
			return result, nil
		} else {
			result := make(map[string]interface{})
			v.ForEach(func(key lua.LValue, value lua.LValue) {
				converted, _ := FromLua(L, value)
				result[key.String()] = converted
			})
			return result, nil
		}
	case lua.LString:
		return string(v), nil
	case lua.LBool:
		return bool(v), nil
	case lua.LNumber:
		return float64(v), nil
	default:
		return nil, nil
	}
}

func IsLuaTableArray(L *lua.LState, v *lua.LTable) (bool, error) {
	logger.Trace("Checking if Lua table is an array")
	L.SetGlobal("table_to_check", v)

	// Use our predefined helper function from InitLuaHelpers
	err := L.DoString(`is_array = isArray(table_to_check)`)
	if err != nil {
		logger.Error("Error determining if table is an array: %v", err)
		return false, fmt.Errorf("error determining if table is array: %w", err)
	}

	// Check the result of our Lua function
	isArray := L.GetGlobal("is_array")
	// LVIsFalse returns true if a given LValue is a nil or false otherwise false.
	result := !lua.LVIsFalse(isArray)
	logger.Trace("Lua table is array: %v", result)
	return result, nil
}

// InitLuaHelpers initializes common Lua helper functions
func InitLuaHelpers(L *lua.LState) error {
	logger.Debug("Loading Lua helper functions")

	helperScript := `
-- Custom Lua helpers for math operations
function min(a, b) return math.min(a, b) end
function max(a, b) return math.max(a, b) end
function round(x, n)
	if n == nil then n = 0 end
	return math.floor(x * 10^n + 0.5) / 10^n
end
function floor(x) return math.floor(x) end
function ceil(x) return math.ceil(x) end
function upper(s) return string.upper(s) end
function lower(s) return string.lower(s) end
function format(s, ...) return string.format(s, ...) end
function trim(s) return string.gsub(s, "^%s*(.-)%s*$", "%1") end

-- String split helper
function strsplit(inputstr, sep)
  if sep == nil then
    sep = "%s"
  end
  local t = {}
  for str in string.gmatch(inputstr, "([^"..sep.."]+)") do
    table.insert(t, str)
  end
  return t
end

---@param table table
---@param depth number?
function DumpTable(table, depth)
	if depth == nil then
		depth = 0
	end
	if (depth > 200) then
		print("Error: Depth > 200 in dumpTable()")
		return
	end
	for k, v in pairs(table) do
		if (type(v) == "table") then
			print(string.rep("  ", depth) .. k .. ":")
			DumpTable(v, depth + 1)
		else
			print(string.rep("  ", depth) .. k .. ": ", v)
		end
	end
end

-- String to number conversion helper
function num(str)
    return tonumber(str) or 0
end

-- Number to string conversion
function str(num)
    return tostring(num)
end

-- Check if string is numeric
function is_number(str)
    return tonumber(str) ~= nil
end

function isArray(t)
    if type(t) ~= "table" then return false end
    local max = 0
    local count = 0
    for k, _ in pairs(t) do
        if type(k) ~= "number" or k < 1 or math.floor(k) ~= k then
            return false
        end
        max = math.max(max, k)
        count = count + 1
    end
    return max == count
end

modified = false
`
	if err := L.DoString(helperScript); err != nil {
		logger.Error("Failed to load Lua helper functions: %v", err)
		return fmt.Errorf("error loading helper functions: %v", err)
	}

	logger.Debug("Setting up Lua print function to Go")
	L.SetGlobal("print", L.NewFunction(printToGo))
	L.SetGlobal("fetch", L.NewFunction(fetch))
	return nil
}

// LimitString truncates a string to maxLen and adds "..." if truncated
func LimitString(s string, maxLen int) string {
	s = strings.ReplaceAll(s, "\n", "\\n")
	if len(s) <= maxLen {
		return s
	}
	return s[:maxLen-3] + "..."
}

func PrependLuaAssignment(luaExpr string) string {
	// Auto-prepend v1 for expressions starting with operators
	if strings.HasPrefix(luaExpr, "*") ||
		strings.HasPrefix(luaExpr, "/") ||
		strings.HasPrefix(luaExpr, "+") ||
		strings.HasPrefix(luaExpr, "-") ||
		strings.HasPrefix(luaExpr, "^") ||
		strings.HasPrefix(luaExpr, "%") {
		luaExpr = "v1 = v1" + luaExpr
	} else if strings.HasPrefix(luaExpr, "=") {
		// Handle direct assignment with = operator
		luaExpr = "v1 " + luaExpr
	}

	// Add assignment if needed
	if !strings.Contains(luaExpr, "=") {
		luaExpr = "v1 = " + luaExpr
	}
	return luaExpr
}

// BuildLuaScript prepares a Lua expression from shorthand notation
func BuildLuaScript(luaExpr string) string {
	logger.Debug("Building Lua script from expression: %s", luaExpr)

	luaExpr = PrependLuaAssignment(luaExpr)

	// This allows the user to specify whether or not they modified a value
	// If they do nothing we assume they did modify (no return at all)
	// If they return before our return then they themselves specify what they did
	// If nothing is returned lua assumes nil
	// So we can say our value was modified if the return value is either nil or true
	// If the return value is false then the user wants to keep the original
	fullScript := fmt.Sprintf(`
		function run()
			%s
		end
		local res = run()
		modified = res == nil or res
	`, luaExpr)

	return fullScript
}

func printToGo(L *lua.LState) int {
	top := L.GetTop()

	args := make([]interface{}, top)
	for i := 1; i <= top; i++ {
		args[i-1] = L.Get(i)
	}

	// Format the message with proper spacing between arguments
	var parts []string
	for _, arg := range args {
		parts = append(parts, fmt.Sprintf("%v", arg))
	}
	message := strings.Join(parts, " ")

	// Use the LUA log level with a script tag
	logger.Lua("%s", message)
	return 0
}

func fetch(L *lua.LState) int {
	// Get URL from first argument
	url := L.ToString(1)
	if url == "" {
		L.Push(lua.LNil)
		L.Push(lua.LString("URL is required"))
		return 2
	}

	// Get options from second argument if provided
	var method string = "GET"
	var headers map[string]string = make(map[string]string)
	var body string = ""

	if L.GetTop() > 1 {
		options := L.ToTable(2)
		if options != nil {
			// Get method
			if methodVal := options.RawGetString("method"); methodVal != lua.LNil {
				method = methodVal.String()
			}

			// Get headers
			if headersVal := options.RawGetString("headers"); headersVal != lua.LNil {
				if headersTable, ok := headersVal.(*lua.LTable); ok {
					headersTable.ForEach(func(key lua.LValue, value lua.LValue) {
						headers[key.String()] = value.String()
					})
				}
			}

			// Get body
			if bodyVal := options.RawGetString("body"); bodyVal != lua.LNil {
				body = bodyVal.String()
			}
		}
	}

	// Create HTTP request
	req, err := http.NewRequest(method, url, strings.NewReader(body))
	if err != nil {
		L.Push(lua.LNil)
		L.Push(lua.LString(fmt.Sprintf("Error creating request: %v", err)))
		return 2
	}

	// Set headers
	for key, value := range headers {
		req.Header.Set(key, value)
	}

	// Make request
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		L.Push(lua.LNil)
		L.Push(lua.LString(fmt.Sprintf("Error making request: %v", err)))
		return 2
	}
	defer resp.Body.Close()

	// Read response body
	bodyBytes, err := io.ReadAll(resp.Body)
	if err != nil {
		L.Push(lua.LNil)
		L.Push(lua.LString(fmt.Sprintf("Error reading response: %v", err)))
		return 2
	}

	// Create response table
	responseTable := L.NewTable()
	responseTable.RawSetString("status", lua.LNumber(resp.StatusCode))
	responseTable.RawSetString("statusText", lua.LString(resp.Status))
	responseTable.RawSetString("ok", lua.LBool(resp.StatusCode >= 200 && resp.StatusCode < 300))
	responseTable.RawSetString("body", lua.LString(string(bodyBytes)))

	// Set headers in response
	headersTable := L.NewTable()
	for key, values := range resp.Header {
		headersTable.RawSetString(key, lua.LString(values[0]))
	}
	responseTable.RawSetString("headers", headersTable)

	L.Push(responseTable)
	return 1
}