// Package application composes the Go backend foundation Modules.
package application

import (
	"context"
	"net/http"
	"os"

	"git.nianxx.cn/wangxuming/NianAIGC/backend/internal/httpapi"
	"git.nianxx.cn/wangxuming/NianAIGC/backend/internal/postgres"
)

type Options struct {
	Context  context.Context
	Getenv   postgres.Getenv
	ReadFile postgres.ReadFile
}

type App struct {
	handler http.Handler
	db      *postgres.Module
}

func New(options Options) (*App, error) {
	ctx := options.Context
	if ctx == nil {
		ctx = context.Background()
	}
	getenv := options.Getenv
	if getenv == nil {
		getenv = os.Getenv
	}
	readFile := options.ReadFile
	if readFile == nil {
		readFile = os.ReadFile
	}

	config, err := postgres.ParseConfig(getenv, readFile)
	if err != nil {
		return nil, err
	}
	database, err := postgres.Open(ctx, config)
	if err != nil {
		return nil, err
	}
	readiness := databaseReadiness{config: config, store: database.Store}
	return &App{
		db:      database,
		handler: httpapi.NewHandler(readiness),
	}, nil
}

func (app *App) Handler() http.Handler {
	return app.handler
}

func (app *App) Close() {
	if app.db != nil {
		app.db.Close()
	}
}

type databaseReadiness struct {
	config postgres.Config
	store  *postgres.Store
}

func (adapter databaseReadiness) Status() httpapi.DatabaseStatus {
	configured := adapter.config.Backend == postgres.BackendLocal || adapter.config.DatabaseURL != ""
	return httpapi.DatabaseStatus{
		Backend:    string(adapter.config.Backend),
		Configured: configured,
	}
}

func (adapter databaseReadiness) Ready(ctx context.Context) (httpapi.DatabaseStatus, error) {
	status := adapter.Status()
	return status, adapter.store.Readiness(ctx)
}