#!/usr/bin/env python3
"""Generate AgentCheckin app icons as PNG files (pure stdlib, no PIL).

Design: rounded gradient tile + calendar outline + check mark (daily check-in).
"""
import os
import struct
import zlib

BASE = os.path.join(os.path.dirname(os.path.abspath(__file__)), "AgentCheckin")


class Canvas:
    def __init__(self, w, h, scale=4):
        self.w, self.h, self.s = w, h, scale
        self.W, self.H = w * scale, h * scale
        self.px = [(0, 0, 0, 0)] * (self.W * self.H)

    def _set(self, x, y, rgba):
        if 0 <= x < self.W and 0 <= y < self.H:
            i = y * self.W + x
            r, g, b, a = rgba
            orr, og, ob, oa = self.px[i]
            na = a / 255.0 + oa / 255.0 * (1 - a / 255.0)
            if na == 0:
                self.px[i] = (0, 0, 0, 0)
            else:
                nr = (r * a / 255.0 + orr * oa / 255.0 * (1 - a / 255.0)) / na
                ng = (g * a / 255.0 + og * g / 255.0 * (1 - a / 255.0)) / na
                nb = (b * a / 255.0 + ob * oa / 255.0 * (1 - a / 255.0)) / na
                self.px[i] = (int(nr), int(ng), int(nb), int(na * 255))

    def rect(self, x, y, w, h, rgba):
        for yy in range(int(y), int(y + h)):
            for xx in range(int(x), int(x + w)):
                self._set(xx, yy, rgba)

    def rounded(self, x, y, w, h, rad, rgba):
        for yy in range(y, y + h):
            for xx in range(x, x + w):
                dx = max(x + rad - xx, xx - (x + w - 1 - rad), 0)
                dy = max(y + rad - yy, yy - (y + h - 1 - rad), 0)
                if dx * dx + dy * dy <= rad * rad:
                    self._set(xx, yy, rgba)

    def ring(self, x, y, w, h, rad, thick, rgba):
        for yy in range(y, y + h):
            for xx in range(x, x + w):
                def outside(px, py, shrink):
                    ddx = max(x + rad + shrink - px, px - (x + w - 1 - rad - shrink), 0)
                    ddy = max(y + rad + shrink - py, py - (y + h - 1 - rad - shrink), 0)
                    return ddx * ddx + ddy * ddy > (rad + shrink) * (rad + shrink)
                if not outside(xx, yy, 0) and outside(xx, yy, thick):
                    self._set(xx, yy, rgba)

    def line(self, x1, y1, x2, y2, thick, rgba):
        steps = int(max(abs(x2 - x1), abs(y2 - y1)) * 2) + 1
        for i in range(steps + 1):
            t = i / steps
            cx = x1 + (x2 - x1) * t
            cy = y1 + (y2 - y1) * t
            r = thick / 2.0
            for yy in range(int(cy - r) - 1, int(cy + r) + 2):
                for xx in range(int(cx - r) - 1, int(cx + r) + 2):
                    if (xx - cx) ** 2 + (yy - cy) ** 2 <= r * r:
                        self._set(xx, yy, rgba)

    def gradient_fill(self, x, y, w, h, rad, c1, c2):
        for yy in range(y, y + h):
            t = (yy - y) / max(h - 1, 1)
            r = int(c1[0] + (c2[0] - c1[0]) * t)
            g = int(c1[1] + (c2[1] - c1[1]) * t)
            b = int(c1[2] + (c2[2] - c1[2]) * t)
            for xx in range(x, x + w):
                dx = max(x + rad - xx, xx - (x + w - 1 - rad), 0)
                dy = max(y + rad - yy, yy - (y + h - 1 - rad), 0)
                if dx * dx + dy * dy <= rad * rad:
                    self._set(xx, yy, (r, g, b, 255))

    def save(self, path):
        s = self.s
        rows = []
        for y in range(self.h):
            row = bytearray([0])
            for x in range(self.w):
                rs = gs = bs = as_ = 0
                cnt = 0
                for dy in range(s):
                    for dx in range(s):
                        p = self.px[(y * s + dy) * self.W + (x * s + dx)]
                        rs += p[0]; gs += p[1]; bs += p[2]; as_ += p[3]
                        cnt += 1
                row += bytes((rs // cnt, gs // cnt, bs // cnt, as_ // cnt))
            rows.append(bytes(row))
        raw = b"".join(rows)

        def chunk(tag, data):
            c = struct.pack(">I", len(data)) + tag + data
            return c + struct.pack(">I", zlib.crc32(tag + data) & 0xFFFFFFFF)

        png = b"\x89PNG\r\n\x1a\n"
        png += chunk(b"IHDR", struct.pack(">IIBBBBB", self.w, self.h, 8, 6, 0, 0, 0))
        png += chunk(b"IDAT", zlib.compress(raw, 9))
        png += chunk(b"IEND", b"")
        with open(path, "wb") as f:
            f.write(png)


def draw_icon(size):
    c = Canvas(size, size)
    S = c.s
    u = S
    m = int(size * 0.05) * S

    # gradient tile
    c.gradient_fill(m, m, c.W - 2 * m, c.H - 2 * m, int(size * 0.22) * S,
                    (59, 108, 255), (122, 90, 248))

    # calendar body
    bx, by = int(size * 0.22) * S, int(size * 0.24) * S
    bw, bh = int(size * 0.56) * S, int(size * 0.52) * S
    rad = int(size * 0.09) * S
    thick = max(int(size * 0.05) * S, 2 * S)
    c.ring(bx, by, bw, bh, rad, thick, (255, 255, 255, 255))

    # hangers
    hw, hh = int(size * 0.07) * S, int(size * 0.12) * S
    c.rounded(bx + bw // 2 - int(size * 0.16) * S, by - hh // 2, hw, hh, hw // 2, (255, 255, 255, 255))
    c.rounded(bx + bw // 2 + int(size * 0.09) * S, by - hh // 2, hw, hh, hw // 2, (255, 255, 255, 255))

    # header line
    ly = by + int(size * 0.13) * S
    c.line(bx + thick // 2, ly, bx + bw - thick // 2, ly, thick, (255, 255, 255, 255))

    # check mark
    cx1 = bx + int(size * 0.13) * S
    cy1 = by + int(size * 0.30) * S
    t2 = max(int(size * 0.065) * S, 2 * S)
    c.line(cx1, cy1, cx1 + int(size * 0.09) * S, cy1 + int(size * 0.09) * S, t2, (126, 240, 178, 255))
    c.line(cx1 + int(size * 0.09) * S, cy1 + int(size * 0.09) * S,
           cx1 + int(size * 0.26) * S, cy1 - int(size * 0.11) * S, t2, (126, 240, 178, 255))
    return c


def main():
    paths = [
        (64, os.path.join(BASE, "ICON.PNG")),
        (256, os.path.join(BASE, "ICON_256.PNG")),
        (64, os.path.join(BASE, "app/ui/images/icon_64.png")),
        (256, os.path.join(BASE, "app/ui/images/icon_256.png")),
    ]
    for size, path in paths:
        c = draw_icon(size)
        c.save(path)
        print("wrote", path, os.path.getsize(path), "bytes")


if __name__ == "__main__":
    main()