//go:build !midnight
package main

import (
	rt "github.com/arnodel/golua/runtime"
	"github.com/maxlandon/readline"
)

func setupTabCompleter(rl *readline.Instance) {
	rl.TabCompleter = func(line []rune, pos int, _ readline.DelayedTabContext) (string, []*readline.CompletionGroup) {
		term := rt.NewTerminationWith(l.UnderlyingRuntime().MainThread().CurrentCont(), 2, false)
		compHandle := hshMod.Get(rt.StringValue("completion")).AsTable().Get(rt.StringValue("handler"))
		err := rt.Call(l.UnderlyingRuntime().MainThread(), compHandle, []rt.Value{rt.StringValue(string(line)),
		rt.IntValue(int64(pos))}, term)

		var compGroups []*readline.CompletionGroup
		if err != nil {
			return "", compGroups
		}

		luaCompGroups := term.Get(0)
		luaPrefix := term.Get(1)

		if luaCompGroups.Type() != rt.TableType {
			return "", compGroups
		}

		groups := luaCompGroups.AsTable()
		// prefix is optional
		pfx, _ := luaPrefix.TryString()

		util.ForEach(groups, func(key rt.Value, val rt.Value) {
			if key.Type() != rt.IntType || val.Type() != rt.TableType {
				return
			}

			valTbl := val.AsTable()
			luaCompType := valTbl.Get(rt.StringValue("type"))
			luaCompItems := valTbl.Get(rt.StringValue("items"))

			if luaCompType.Type() != rt.StringType || luaCompItems.Type() != rt.TableType {
				return
			}

			items := []string{}
			itemDescriptions := make(map[string]string)

			util.ForEach(luaCompItems.AsTable(), func(lkey rt.Value, lval rt.Value) {
				if keytyp := lkey.Type(); keytyp == rt.StringType {
					// ['--flag'] = {'description', '--flag-alias'}
					itemName, ok := lkey.TryString()
					vlTbl, okk := lval.TryTable()
					if !ok && !okk {
						// TODO: error
						return
					}

					items = append(items, itemName)
					itemDescription, ok := vlTbl.Get(rt.IntValue(1)).TryString()
					if !ok {
						// TODO: error
						return
					}
					itemDescriptions[itemName] = itemDescription
				} else if keytyp == rt.IntType {
					vlStr, ok := lval.TryString()
						if !ok {
							// TODO: error
							return
						}
						items = append(items, vlStr)
				} else {
					// TODO: error
					return
				}
			})

			var dispType readline.TabDisplayType
			switch luaCompType.AsString() {
				case "grid": dispType = readline.TabDisplayGrid
				case "list": dispType = readline.TabDisplayList
				// need special cases, will implement later
				//case "map": dispType = readline.TabDisplayMap
			}

			compGroups = append(compGroups, &readline.CompletionGroup{
				DisplayType: dispType,
				Descriptions: itemDescriptions,
				Suggestions: items,
				TrimSlash: false,
				NoSpace: true,
			})
		})

		return pfx, compGroups
	}
}