"""工程符号库：从参考设计的 .kicad_sch 抽符号，或按引脚表程序化生成方框符号。

    from schgen.symgen import grab_from_sch, box_symbol, write_lib
    blocks = [grab_from_sch(r"...\\SMOD\\07_PWR.kicad_sch", "IC_SCH:root_0_TPS7A92_IC_SCH.SchLib",
                            "TPS7A9201DSK"),
              box_symbol("TPS65235", ref="U", value="TPS65235",
                         left=[("2", "VIN", "power_in"), ...], right=[...], top=[...], bottom=[...])]
    write_lib(r"...\\lib\\myboard.kicad_sym", blocks)

先查参考设计有没有现成符号（抄过来最省事、引脚最不容易错），没有才自己生成。
"""
import io
import re

from .kicad_lib import balanced

PIN_TYPES = {"input", "output", "bidirectional", "tri_state", "passive", "free",
             "unspecified", "power_in", "power_out", "open_collector", "open_emitter",
             "no_connect"}


def rename(block, old, new):
    """把顶层符号名和子单元名 old_x_y 一并改掉。"""
    block = block.replace('(symbol "%s"' % old, '(symbol "%s"' % new, 1)
    for o in (old.split(':')[-1], old):
        block = re.sub(r'\(symbol "%s(_\d+_\d+)"' % re.escape(o),
                       lambda m: '(symbol "%s%s"' % (new, m.group(1)), block)
    return block


def grab_from_sch(sch_path, lib_id, new_name):
    """从 .kicad_sch 的 lib_symbols 段里按 lib_id 抽出符号并改名。"""
    t = io.open(sch_path, encoding="utf-8").read()
    i = t.find('(symbol "%s"' % lib_id)
    if i < 0:
        raise KeyError("%s 里没有 %s" % (sch_path, lib_id))
    return rename(balanced(t, i), lib_id, new_name)


def pin_count(block):
    return len(re.findall(r'\(pin\s+\w+\s+\w+', block))


def box_symbol(name, ref="U", value=None, desc="", left=(), right=(), top=(), bottom=(),
               pitch=2.54, pin_len=5.08, min_w=15.24, min_h=10.16, hidden_num=False,
               footprint=""):
    """方框符号。每边是 [(号, 名[, 类型]), ...]，按顺序从上到下 / 从左到右排开；
    号为 None 表示那一格留空（用来把引脚分组）。宽高按引脚名长度与数量自动撑开。"""
    value = value or name

    def norm(side):
        out = []
        for p in side:
            if p is None:
                out.append(None)
                continue
            num, nm = p[0], p[1]
            typ = p[2] if len(p) > 2 else "passive"
            assert typ in PIN_TYPES, typ
            out.append((num, nm, typ))
        return out

    L, Rr, T, B = norm(left), norm(right), norm(top), norm(bottom)
    # pitch 可以是一个数，也可以按边分别给：{"left":7.62,"right":5.08,"top":12.7,"bottom":12.7}
    pd = pitch if isinstance(pitch, dict) else {}
    pl, pr_, pt, pb = (pd.get(k, 2.54) if pd else pitch for k in ("left", "right", "top", "bottom"))
    namew = lambda side: max([len(p[1]) for p in side if p] or [0]) * 1.1
    nh = max(len(T), len(B), 0)
    h = max(min_h, (len(L) + 1) * pl, (len(Rr) + 1) * pr_)
    w = max(min_w, namew(L) + namew(Rr) + 5.08, (len(T) + 1) * pt, (len(B) + 1) * pb,
            (max([len(p[1]) for p in T + B if p] or [0]) * 1.1 + 2.54) * 2 if nh else 0)
    w = round(w / 2.54 / 2 + 0.49) * 2.54 * 2          # 宽高取 2.54 的偶数倍，引脚落格点
    h = round(h / 2.54 / 2 + 0.49) * 2.54 * 2
    hw, hh = w / 2.0, h / 2.0
    lines = ['  (symbol "%s"' % name,
             '    (pin_names (offset 0.762))%s' % (' (pin_numbers hide)' if hidden_num else ''),
             '    (exclude_from_sim no) (in_bom yes) (on_board yes)',
             '    (property "Reference" "%s" (at %.2f %.2f 0)'
             ' (effects (font (size 1.27 1.27)) (justify left)))' % (ref, -hw, hh + 1.27),
             '    (property "Value" "%s" (at %.2f %.2f 0)'
             ' (effects (font (size 1.27 1.27)) (justify left)))' % (value, -hw, -hh - 1.27),
             '    (property "Footprint" "%s" (at 0 0 0) (effects (font (size 1.27 1.27)) hide))'
             % footprint,
             '    (property "Datasheet" "" (at 0 0 0) (effects (font (size 1.27 1.27)) hide))',
             '    (property "Description" "%s" (at 0 0 0) (effects (font (size 1.27 1.27)) hide))'
             % desc.replace('"', "'"),
             '    (symbol "%s_0_1"' % name,
             '      (rectangle (start %.2f %.2f) (end %.2f %.2f)'
             ' (stroke (width 0.254) (type default)) (fill (type background)))' % (-hw, hh, hw, -hh),
             '    )',
             '    (symbol "%s_1_1"' % name]

    def pin(num, nm, typ, x, y, ang):
        lines.append('      (pin %s line (at %.2f %.2f %d) (length %.2f)' % (typ, x, y, ang, pin_len))
        lines.append('        (name "%s" (effects (font (size 1.27 1.27))))' % nm)
        lines.append('        (number "%s" (effects (font (size 1.27 1.27)))))' % num)

    def col(n, pitch):                # 竖边：从上往下，居中
        top_y = (n - 1) * pitch / 2.0
        return [round((top_y - k * pitch) / 1.27) * 1.27 for k in range(n)]

    def row(n, pitch):
        x0 = -(n - 1) * pitch / 2.0
        return [round((x0 + k * pitch) / 1.27) * 1.27 for k in range(n)]

    for p, y in zip(L, col(len(L), pl)):
        if p:
            pin(p[0], p[1], p[2], -hw - pin_len, y, 0)
    for p, y in zip(Rr, col(len(Rr), pr_)):
        if p:
            pin(p[0], p[1], p[2], hw + pin_len, y, 180)
    for p, x in zip(T, row(len(T), pt)):
        if p:
            pin(p[0], p[1], p[2], x, hh + pin_len, 270)
    for p, x in zip(B, row(len(B), pb)):
        if p:
            pin(p[0], p[1], p[2], x, -hh - pin_len, 90)
    lines += ['    )', '  )']
    return "\n".join(lines)


def write_lib(path, blocks):
    out = ['(kicad_symbol_lib (version 20231120) (generator "kicad_flow_schgen") (generator_version "8.0")']
    out += blocks
    out.append(')')
    io.open(path, "w", encoding="utf-8").write("\n".join(out) + "\n")
    names = [re.match(r'\s*\(symbol "([^"]+)"', b).group(1) for b in blocks]
    for b, n in zip(blocks, names):
        print("  符号 %-24s 引脚 %3d" % (n, pin_count(b)))
    return path