package main

import (
	"flag"
	"fmt"
	protogen2 "git.diulo.com/mogfee/kit/protogen"
	"google.golang.org/protobuf/compiler/protogen"
	"google.golang.org/protobuf/types/descriptorpb"
	"strings"
)

func main() {
	u := &Kit{
		imports: map[string]string{},
	}
	var flags flag.FlagSet
	flags.StringVar(&u.Prefix, "prefix", "", "API path prefix")
	protogen.Options{
		ParamFunc: flags.Set,
	}.Run(u.Generate)
	protogen.Options{}.Run(u.Generate)
}

type Kit struct {
	Prefix  string
	imports map[string]string
}

func (u *Kit) addImports(imp string) {
	u.imports[imp] = imp
}

func (u *Kit) packageName(f *protogen.File) string {
	a := f.Desc.Options().(*descriptorpb.FileOptions)
	p := strings.Split(*a.GoPackage, ";")
	if len(p) == 2 {
		return p[1]
	}
	return fmt.Sprintf("%s", f.Desc.Name())
}
func (u *Kit) Generate(plugin *protogen.Plugin) error {
	if len(plugin.Files) < 1 {
		return nil
	}
	u.addImports("context")
	u.addImports("git.diulo.com/mogfee/kit/middleware")
	u.addImports("git.diulo.com/mogfee/kit/errors")
	u.addImports("git.diulo.com/mogfee/kit/response")
	u.addImports("github.com/gin-gonic/gin")
	for _, f := range plugin.Files {
		if len(f.Services) == 0 {
			continue
		}
		fname := f.GeneratedFilenamePrefix + ".http.go"
		t := plugin.NewGeneratedFile(fname, f.GoImportPath)
		t.P("package ", u.packageName(f))
		t.P("import (")
		for _, v := range u.imports {
			t.P(`"` + v + `"`)
		}
		t.P(")")

		for _, s := range f.Services {
			serverName := s.GoName
			t.P(`func Register`, serverName, `Handler(app *gin.Engine,srv `, serverName, `Server,m ...middleware.Middleware) {`)
			for _, m := range s.Methods {
				method, path := protogen2.GetProtoMethod(m)
				if method == "" {
					continue
				}
				if u.Prefix != "" {
					path = u.Prefix + path
				}
				t.P(`app.`, method, `("`, path, `",http`, m.GoName, `Handler(srv,m...))`)
			}
			t.P(`}`)
		}
		for _, s := range f.Services {
			serverName := s.GoName
			for _, m := range s.Methods {
				method, _ := protogen2.GetProtoMethod(m)
				if method == "" {
					continue
				}
				switch method {
				case protogen2.METHOD_GET:
					u.genGet(serverName, t, m)
				case protogen2.METHOD_POST:
					u.genPost(serverName, t, m)
				case protogen2.METHOD_DELETE:
					u.genDelete(serverName, t, m)
				case protogen2.METHOD_PUT:
					u.genPut(serverName, t, m)
				}
			}
		}
	}
	return nil
}

func (u *Kit) genGet(serverName string, t *protogen.GeneratedFile, m *protogen.Method) {
	t.P("func http", m.GoName, "Handler(srv ", serverName, "Server,m ...middleware.Middleware)func(c *gin.Context){")
	t.P(`return func(c *gin.Context) {
		var post `, m.Input.GoIdent.GoName, `
		resp := response.New(c)
		if err := resp.BindQuery(&post); err != nil {
			resp.Error(err)
			return
		}
		h := func(ctx context.Context, a any) (any, error) {
			return srv.`, m.GoName, `(ctx, a.(*`, m.Input.GoIdent.GoName, `))
		}
		out, err := middleware.HttpMiddleware(c, h, m...)(c, &post)
		if err != nil {
			resp.Error(err)
		} else {
			if v, ok := out.(*`, m.Output.GoIdent.GoName, `); ok {
				resp.Success(v)
			} else {
				resp.Error(errors.InternalServer("RESULT_TYPE_ERROR", "`, m.Output.GoIdent.GoName, `"))
			}
		}
	}`)
	t.P("}")
}
func (u *Kit) genPost(serverName string, t *protogen.GeneratedFile, m *protogen.Method) {
	t.P("func http", m.GoName, "Handler(srv ", serverName, "Server,m ...middleware.Middleware)func(c *gin.Context){")
	t.P(`return func(c *gin.Context) {
		var post `, m.Input.GoIdent.GoName, `
		resp := response.New(c)
		if err := resp.BindJSON(&post); err != nil {
			resp.Error(err)
			return
		}
		h := func(ctx context.Context, a any) (any, error) {
			return srv.`, m.GoName, `(ctx, a.(*`, m.Input.GoIdent.GoName, `))
		}
		out, err := middleware.HttpMiddleware(c, h, m...)(c, &post)
		if err != nil {
			resp.Error(err)
		} else {
			if v, ok := out.(*`, m.Output.GoIdent.GoName, `); ok {
				resp.Success(v)
			} else {
				resp.Error(errors.InternalServer("RESULT_TYPE_ERROR", "`, m.Output.GoIdent.GoName, `"))
			}
		}
	}`)
	t.P("}")
}
func (u *Kit) genDelete(serverName string, t *protogen.GeneratedFile, m *protogen.Method) {
	t.P("func http", m.GoName, "Handler(srv ", serverName, "Server,m ...middleware.Middleware)func(c *gin.Context){")
	t.P(`return func(c *gin.Context) {
		var post `, m.Input.GoIdent.GoName, `
		resp := response.New(c)
		if err := resp.BindJSON(&post); err != nil {
			resp.Error(err)
			return
		}
		h := func(ctx context.Context, a any) (any, error) {
			return srv.`, m.GoName, `(ctx, a.(*`, m.Input.GoIdent.GoName, `))
		}
		out, err := middleware.HttpMiddleware(c, h, m...)(c, &post)
		if err != nil {
			resp.Error(err)
		} else {
			if v, ok := out.(*`, m.Output.GoIdent.GoName, `); ok {
				resp.Success(v)
			} else {
				resp.Error(errors.InternalServer("RESULT_TYPE_ERROR", "`, m.Output.GoIdent.GoName, `"))
			}
		}
	}`)
	t.P("}")
}

func (u *Kit) genPut(serverName string, t *protogen.GeneratedFile, m *protogen.Method) {
	t.P("func http", m.GoName, "Handler(srv ", serverName, "Server,m ...middleware.Middleware)func(c *gin.Context){")
	t.P(`return func(c *gin.Context) {
		var post `, m.Input.GoIdent.GoName, `
		resp := response.New(c)
		if err := resp.BindJSON(&post); err != nil {
			resp.Error(err)
			return
		}
		h := func(ctx context.Context, a any) (any, error) {
			return srv.`, m.GoName, `(ctx, a.(*`, m.Input.GoIdent.GoName, `))
		}
		out, err := middleware.HttpMiddleware(c, h, m...)(c, &post)
		if err != nil {
			resp.Error(err)
		} else {
			if v, ok := out.(*`, m.Output.GoIdent.GoName, `); ok {
				resp.Success(v)
			} else {
				resp.Error(errors.InternalServer("RESULT_TYPE_ERROR", "`, m.Output.GoIdent.GoName, `"))
			}
		}
	}`)
	t.P("}")
}