package templates

import (
	"os"
	"slices"
	"testing"

	"github.com/jinzhu/copier"
	"gopkg.in/yaml.v3"
)

// test renders and instantiates plus yaml-parses the template per usage
func test(t *testing.T, tmpl Template, values map[string]interface{}, cb func(values map[string]interface{})) {
	b, _, err := tmpl.RenderResult(TemplateRenderModeInstance, values)
	if err != nil {
		t.Log(string(b))
		t.Error(err)
		return
	}

	var instance interface{}
	if err := yaml.Unmarshal(b, &instance); err != nil {
		t.Log(string(b))
		t.Error(err)
		return
	}

	// actually run the instance if not on CI
	if os.Getenv("CI") == "" {
		cb(values)
	}
}

func TestClass(t *testing.T, class Class, instantiate func(t *testing.T, values map[string]interface{})) {
	for _, tmpl := range ByClass(class) {
		tmpl := tmpl

		t.Run(tmpl.Template, func(t *testing.T) {
			// set default values for all params
			values := tmpl.Defaults(TemplateRenderModeUnitTest)

			// set the template value which is needed for rendering
			values["template"] = tmpl.Template

			// set modbus default test values
			if values[ParamModbus] != nil {
				modbusChoices := tmpl.ModbusChoices()
				// we only test one modbus setup
				if slices.Contains(modbusChoices, ModbusChoiceTCPIP) {
					values[ModbusKeyTCPIP] = true
				} else {
					values[ModbusKeyRS485TCPIP] = true
				}
				tmpl.ModbusValues(TemplateRenderModeUnitTest, values)
			}

			usages := tmpl.Usages()
			if len(usages) == 0 {
				test(t, tmpl, values, func(values map[string]interface{}) {
					instantiate(t, values)
				})

				return
			}

			for _, u := range usages {
				// create a copy of the map for parallel execution
				usageValues := make(map[string]interface{}, len(values)+1)
				if err := copier.Copy(&usageValues, values); err != nil {
					panic(err)
				}
				usageValues[ParamUsage] = u

				// subtest for each usage
				t.Run(u, func(t *testing.T) {
					t.Parallel()

					test(t, tmpl, usageValues, func(values map[string]interface{}) {
						instantiate(t, values)
					})
				})
			}
		})
	}
}