package build

import (
	"fmt"
	"go/parser"
	"go/token"
	"os"
	"path/filepath"
	"strconv"
	"strings"
)

var modelsSiblingLeaves = []string{
	"classes",
	"controllers",
	"console",
	"jobs",
	"middleware",
	"updates",
}

func checkModelsLeaf(appDir string, m Manifest) error {
	for _, p := range m.Plugins {
		pluginDir := localModuleDir(appDir, p.Module)
		if pluginDir == "" {
			pluginDir = filepath.Join(appDir, "plugins", pluginName(p.ID))
		}
		if !underRoot(appDir, pluginDir) {
			continue
		}
		modelsDir := filepath.Join(pluginDir, "models")
		st, err := os.Stat(modelsDir)
		if err != nil || !st.IsDir() {
			continue
		}
		module, err := readModulePath(filepath.Join(pluginDir, "go.mod"))
		if err != nil {
			return err
		}
		if err := inspectModelsImports(p.ID, pluginDir, module, modelsDir); err != nil {
			return err
		}
	}
	return nil
}

func inspectModelsImports(pluginID, pluginDir, module, modelsDir string) error {
	entries, err := os.ReadDir(modelsDir)
	if err != nil {
		return fmt.Errorf("build: read %s: %w", modelsDir, err)
	}
	fset := token.NewFileSet()
	for _, entry := range entries {
		name := entry.Name()
		if entry.IsDir() || !strings.HasSuffix(name, ".go") {
			continue
		}
		path := filepath.Join(modelsDir, name)
		file, err := parser.ParseFile(fset, path, nil, parser.ImportsOnly)
		if err != nil {
			return fmt.Errorf("build: parse %s: %w", path, err)
		}
		rel, err := filepath.Rel(pluginDir, path)
		if err != nil {
			rel = filepath.Join("models", name)
		}
		for _, spec := range file.Imports {
			imp, err := strconv.Unquote(spec.Path.Value)
			if err != nil {
				continue
			}
			for _, sib := range modelsSiblingLeaves {
				prefix := module + "/" + sib
				if imp == prefix || strings.HasPrefix(imp, prefix+"/") {
					return fmt.Errorf("build: plugin %s: %s imports %s", pluginID, filepath.ToSlash(rel), imp)
				}
			}
		}
	}
	return nil
}