// files.zap - a file browser app for ZeaxOS.
// Click a folder to open it; Ctrl+Esc quits.

// #engine

fn join(a, b) {
    if a == "/" { return "/" + b }
    if ends_with(a, "/") { return a + b }
    return a + "/" + b
}

fn parent(p) {
    if p == "/" { return "/" }
    let q = p
    if ends_with(q, "/") { q = substr(q, 0, len(q) - 1) }
    let i = len(q) - 1
    while i > 0 && substr(q, i, 1) != "/" { i = i - 1 }
    if i <= 0 { return "/" }
    return substr(q, 0, i)
}

fn size_text(n) {
    if n < 1024 { return str(n) + " B" }
    return str(n / 1024) + "." + str(n % 1024 * 10 / 1024) + " KB"
}

// #main

let W = gfx_width()
let H = gfx_height()
let TOP = 16
let BG = rgb(10, 14, 18)
let FG = rgb(230, 237, 243)
let MUTED = rgb(122, 138, 154)
let ACCENT = rgb(0, 229, 255)
let GREEN = rgb(0, 255, 102)
let LINE = rgb(42, 58, 74)
let QH = "Ctrl+Esc quits"

let M = 14
let TB = TOP + 44
let TH = 30
let PATHY = TB + 44
let LISTX = M
let LISTY = PATHY + 28
let LISTW = W - 2 * M
let ROWH = 26
let BOT = H - 10
let ROWS = (BOT - LISTY - 8) / ROWH

let cwd = "/"
let names = []
let isdir = []
let labels = []
let sel = -1
let running = true

fn inr(x, y, rx, ry, rw, rh) {
return x >= rx && x < rx + rw && y >= ry && y < ry + rh
}

fn reload() {
names = []
isdir = []
labels = []
let raw = sort(list_dir(cwd))
let pass = 0
while pass < 2 {
for n in raw {
let f = join(cwd, n)
let d = is_dir(f)
if d == (pass == 0) {
push(names, n)
push(isdir, d)
if d { push(labels, n + "/") }
else { push(labels, n + "   " + size_text(file_size(f))) }
}
}
pass = pass + 1
}
sel = -1
}

fn hit(x, y) {
if inr(x, y, M, TB, 64, TH) { return 0 }
if inr(x, y, M + 76, TB, 90, TH) { return 1 }
if x >= LISTX && x < LISTX + LISTW && y >= LISTY && y < LISTY + ROWS * ROWH {
let r = (y - LISTY) / ROWH
if r < ROWS && r < len(names) { return 100 + r }
}
return -1
}

fn on_click(id) {
if id == 0 { cwd = parent(cwd)
reload()
return }
if id == 1 { running = false
return }
let idx = id - 100
if idx >= 0 && idx < len(names) {
sel = idx
if isdir[idx] {
cwd = join(cwd, names[idx])
reload()
}
}
}

fn tb(x, w, textstr, hid, id) {
let hot = hid == id
rect(x, TB, w, TH, hot ? ACCENT : LINE)
text(x + (w - text_w(textstr)) / 2, TB + (TH - 16) / 2, textstr, hot ? ACCENT : FG)
}

fn render(hid) {
fill_rect(0, TOP, W, H - TOP, BG)
text(8, TOP + 4, "Files", GREEN)
text(W - text_w(QH) - 8, TOP + 4, QH, MUTED)
fill_rect(0, TOP + 26, W, 2, LINE)
tb(M, 64, "Up", hid, 0)
tb(M + 76, 90, "Quit", hid, 1)
text(M, PATHY, cwd, ACCENT)
if sel >= 0 && sel < len(names) { text(M, BOT - 24, names[sel], MUTED) }
let i = 0
while i < ROWS {
if i < len(names) {
let ry = LISTY + i * ROWH
let cur = i == sel
let hot = hid == 100 + i
rect(LISTX, ry, LISTW, ROWH - 4, cur ? GREEN : (hot ? ACCENT : LINE))
text(LISTX + 10, ry + 3, labels[i], cur ? GREEN : (hot ? ACCENT : FG))
}
i = i + 1
}
}

reload()
let hid = -2
let pmx = -1
let pmy = -1
let pmb = 0
cursor_show()
while running {
let k = key()
if k == 269 { break }
let mx = mouse_x()
let my = mouse_y()
let mb = mouse_buttons()
let moved = mx != pmx || my != pmy || mb != pmb
pmx = mx
pmy = my
pmb = mb
let id = hit(mx, my)
let click = mb % 2 != 0 && pmb % 2 == 0
if click && id >= 0 { on_click(id) }
if id != hid || click {
cursor_hide()
render(id)
cursor_move(mx, my)
cursor_show()
hid = id
} else if moved {
cursor_move(mx, my)
}
sleep(5)
}
cursor_hide()