// Copyright (c) 2026 Charles KWON OhJun (charleskwonohjun@gmail.com)
// All rights reserved.

// Hash functions for the Five runtime library.
// Harbour: hb_Hash, hb_HGet, hb_HSet, hb_HDel, hb_HHasKey, etc.
package hbrtl

import "five/hbrt"

// HbHash creates a hash from key-value pairs.
// Harbour: hb_Hash(key1, val1, key2, val2, ...) → hHash
func HbHash(t *hbrt.Thread) {
	nParams := t.ParamCount()
	t.Frame(nParams, 0)
	defer t.EndProc()

	h := hbrt.MakeHash()
	hh := h.AsHash()
	for i := 1; i <= nParams-1; i += 2 {
		hh.Keys = append(hh.Keys, t.Local(i))
		hh.Values = append(hh.Values, t.Local(i+1))
	}
	t.PushValue(h)
	t.RetValue()
}

// HbHGet gets a value from a hash by key.
// Harbour: hb_HGet(hHash, xKey) → xValue
func HbHGet(t *hbrt.Thread) {
	t.Frame(2, 0)
	defer t.EndProc()
	hVal := t.Local(1)
	key := t.Local(2)
	hh := hVal.AsHash()
	if hh != nil {
		for i, k := range hh.Keys {
			if valuesEqual(k, key) {
				t.PushValue(hh.Values[i])
				t.RetValue()
				return
			}
		}
	}
	t.PushNil()
	t.RetValue()
}

// HbHSet sets a value in hash by key.
// Harbour: hb_HSet(hHash, xKey, xValue) → hHash
func HbHSet(t *hbrt.Thread) {
	t.Frame(3, 0)
	defer t.EndProc()
	hVal := t.Local(1)
	key := t.Local(2)
	val := t.Local(3)
	hh := hVal.AsHash()
	if hh != nil {
		for i, k := range hh.Keys {
			if valuesEqual(k, key) {
				hh.Values[i] = val
				t.PushValue(hVal)
				t.RetValue()
				return
			}
		}
		hh.Keys = append(hh.Keys, key)
		hh.Values = append(hh.Values, val)
	}
	t.PushValue(hVal)
	t.RetValue()
}

// HbHDel deletes a key from hash.
// Harbour: hb_HDel(hHash, xKey) → hHash
func HbHDel(t *hbrt.Thread) {
	t.Frame(2, 0)
	defer t.EndProc()
	hVal := t.Local(1)
	key := t.Local(2)
	hh := hVal.AsHash()
	if hh != nil {
		for i, k := range hh.Keys {
			if valuesEqual(k, key) {
				hh.Keys = append(hh.Keys[:i], hh.Keys[i+1:]...)
				hh.Values = append(hh.Values[:i], hh.Values[i+1:]...)
				break
			}
		}
	}
	t.PushValue(hVal)
	t.RetValue()
}

// HbHHasKey checks if hash contains a key.
// Harbour: hb_HHasKey(hHash, xKey) → lExists
func HbHHasKey(t *hbrt.Thread) {
	t.Frame(2, 0)
	defer t.EndProc()
	hVal := t.Local(1)
	key := t.Local(2)
	hh := hVal.AsHash()
	if hh != nil {
		for _, k := range hh.Keys {
			if valuesEqual(k, key) {
				t.PushBool(true)
				t.RetValue()
				return
			}
		}
	}
	t.PushBool(false)
	t.RetValue()
}

// HbHKeys returns an array of hash keys.
// Harbour: hb_HKeys(hHash) → aKeys
func HbHKeys(t *hbrt.Thread) {
	t.Frame(1, 0)
	defer t.EndProc()
	hh := t.Local(1).AsHash()
	if hh != nil {
		t.PushValue(hbrt.MakeArrayFrom(hh.Keys))
	} else {
		t.PushValue(hbrt.MakeArray(0))
	}
	t.RetValue()
}

// HbHValues returns an array of hash values.
// Harbour: hb_HValues(hHash) → aValues
func HbHValues(t *hbrt.Thread) {
	t.Frame(1, 0)
	defer t.EndProc()
	hh := t.Local(1).AsHash()
	if hh != nil {
		t.PushValue(hbrt.MakeArrayFrom(hh.Values))
	} else {
		t.PushValue(hbrt.MakeArray(0))
	}
	t.RetValue()
}