package zordfsdb

import (
	"os"
	"path"
	"strings"

	"g.arns.lt/zordsdavini/abcex"
)

type DB struct {
	Root  string
	Nodes map[string]Node
}

type Node struct {
	Key    string
	Value  string
	Nodes  map[string]Node
	Object bool
	List   bool
}

func InitDB(root string) (DB, error) {
	db := DB{Root: root}
	err := db.Refresh()

	return db, err
}

func (db *DB) Refresh() error {
	db.Nodes = make(map[string]Node)

	files, err := os.ReadDir(db.Root)
	if err != nil {
		return err
	}

	for _, file := range files {
		node := Node{Key: file.Name()}
		node.Nodes = make(map[string]Node)

		if file.IsDir() {
			node, err = readDir(db.Root, node)
			if err != nil {
				return err
			}
		} else {
			b, err := os.ReadFile(path.Join(db.Root, file.Name()))
			if err != nil {
				return err
			}

			node.Value = strings.Trim(string(b), "\n")
		}

		db.Nodes[file.Name()] = node
	}

	return nil
}

func readDir(root string, node Node) (Node, error) {
	newRoot := path.Join(root, node.Key)
	files, err := os.ReadDir(newRoot)
	if err != nil {
		return node, err
	}

	for _, file := range files {
		child := Node{Key: file.Name()}
		child.Nodes = make(map[string]Node)

		if file.IsDir() {
			child, err = readDir(newRoot, child)
			if err != nil {
				return node, err
			}
		} else {
			b, err := os.ReadFile(path.Join(newRoot, file.Name()))
			if err != nil {
				return node, err
			}

			child.Value = strings.Trim(string(b), "\n")
		}

		node.Nodes[file.Name()] = child
	}

	node.FixType()

	return node, nil
}

func (node *Node) FixType() {
	node.List = false
	node.Object = false
	for _, child := range node.Nodes {
		if child.Object {
			node.List = true
			break
		}

		node.Object = true
		break
	}
}

func (db *DB) Keys(vpath string) []string {
	keys := []string{}
	fullPath := []string{db.Root}
	fullPath = append(fullPath, strings.Split(vpath, ".")...)
	root := path.Join(fullPath...)
	files, err := os.ReadDir(root)
	if err != nil {
		return keys
	}

	for _, file := range files {
		keys = append(keys, file.Name())
	}

	return keys
}

func (db *DB) GetNode(vpath string) (Node, bool) {
	nodes := db.Nodes
	current := Node{}
STEP_LOOP:
	for _, step := range strings.Split(vpath, ".") {
		for _, node := range nodes {
			if step == node.Key {
				nodes = node.Nodes
				current = node
				continue STEP_LOOP
			}
		}

		return current, false
	}

	return current, true
}

func (db *DB) Get(vpath string) (string, bool) {
	node, found := db.GetNode(vpath)
	if !found {
		return "", false
	}

	return node.Value, true
}

func (db *DB) Inc(vpath string) bool {
	fullPath := []string{db.Root}
	fullPath = append(fullPath, strings.Split(vpath, ".")...)

	val, found := db.Get(vpath)
	if !found {
		return false
	}

	valAbc := abcex.Decode(val)
	valAbc++
	val = abcex.Encode(valAbc)

	os.WriteFile(path.Join(fullPath...), []byte(string(val)), 0644)
	err := db.Refresh()
	if err != nil {
		return false
	}

	return true
}

func (db *DB) Dec(vpath string) bool {
	fullPath := []string{db.Root}
	fullPath = append(fullPath, strings.Split(vpath, ".")...)

	val, found := db.Get(vpath)
	if !found {
		return false
	}

	valAbc := abcex.Decode(val)
	valAbc--
	val = abcex.Encode(valAbc)

	os.WriteFile(path.Join(fullPath...), []byte(string(val)), 0644)
	err := db.Refresh()
	if err != nil {
		return false
	}

	return true
}