| 1 | module json_module |
| 2 | ! Minimal JSON parser/builder for LSP communication |
| 3 | use iso_fortran_env, only: int32, int64, real64 |
| 4 | implicit none |
| 5 | private |
| 6 | |
| 7 | public :: json_value_t, json_object_t, json_array_t |
| 8 | public :: json_parse, json_stringify |
| 9 | public :: json_create_object, json_create_array, json_create_string |
| 10 | public :: json_add_string, json_add_number, json_add_bool, json_add_null |
| 11 | public :: json_add_object, json_add_array |
| 12 | public :: json_get_string, json_get_number, json_get_bool |
| 13 | public :: json_get_object, json_get_array, json_get_value |
| 14 | public :: json_has_key |
| 15 | public :: json_array_size, json_get_array_element, json_array_add_element |
| 16 | public :: JSON_NULL, JSON_BOOL, JSON_NUMBER, JSON_STRING, JSON_ARRAY, JSON_OBJECT |
| 17 | |
| 18 | ! JSON value types |
| 19 | integer, parameter :: JSON_NULL = 0 |
| 20 | integer, parameter :: JSON_BOOL = 1 |
| 21 | integer, parameter :: JSON_NUMBER = 2 |
| 22 | integer, parameter :: JSON_STRING = 3 |
| 23 | integer, parameter :: JSON_ARRAY = 4 |
| 24 | integer, parameter :: JSON_OBJECT = 5 |
| 25 | |
| 26 | ! Forward declarations for recursive types |
| 27 | type :: json_value_t |
| 28 | integer :: value_type = JSON_NULL |
| 29 | logical :: bool_value = .false. |
| 30 | real(real64) :: number_value = 0.0 |
| 31 | character(len=:), allocatable :: string_value |
| 32 | type(json_array_t), pointer :: array_value => null() |
| 33 | type(json_object_t), pointer :: object_value => null() |
| 34 | end type json_value_t |
| 35 | |
| 36 | type :: json_pair_t |
| 37 | character(len=:), allocatable :: key |
| 38 | type(json_value_t) :: value |
| 39 | end type json_pair_t |
| 40 | |
| 41 | type :: json_object_t |
| 42 | type(json_pair_t), allocatable :: pairs(:) |
| 43 | integer :: count = 0 |
| 44 | end type json_object_t |
| 45 | |
| 46 | type :: json_array_t |
| 47 | type(json_value_t), allocatable :: elements(:) |
| 48 | integer :: count = 0 |
| 49 | end type json_array_t |
| 50 | |
| 51 | contains |
| 52 | |
| 53 | function json_create_object() result(obj) |
| 54 | type(json_value_t) :: obj |
| 55 | |
| 56 | obj%value_type = JSON_OBJECT |
| 57 | allocate(obj%object_value) |
| 58 | allocate(obj%object_value%pairs(0)) |
| 59 | obj%object_value%count = 0 |
| 60 | end function json_create_object |
| 61 | |
| 62 | function json_create_array() result(arr) |
| 63 | type(json_value_t) :: arr |
| 64 | |
| 65 | arr%value_type = JSON_ARRAY |
| 66 | allocate(arr%array_value) |
| 67 | allocate(arr%array_value%elements(0)) |
| 68 | arr%array_value%count = 0 |
| 69 | end function json_create_array |
| 70 | |
| 71 | function json_create_string(value) result(str) |
| 72 | character(len=*), intent(in) :: value |
| 73 | type(json_value_t) :: str |
| 74 | |
| 75 | str%value_type = JSON_STRING |
| 76 | str%string_value = value |
| 77 | end function json_create_string |
| 78 | |
| 79 | subroutine json_add_string(obj, key, value) |
| 80 | type(json_value_t), intent(inout) :: obj |
| 81 | character(len=*), intent(in) :: key, value |
| 82 | type(json_pair_t), allocatable :: new_pairs(:) |
| 83 | integer :: n |
| 84 | |
| 85 | if (obj%value_type /= JSON_OBJECT) return |
| 86 | |
| 87 | n = obj%object_value%count |
| 88 | allocate(new_pairs(n + 1)) |
| 89 | |
| 90 | if (n > 0) new_pairs(1:n) = obj%object_value%pairs |
| 91 | |
| 92 | new_pairs(n + 1)%key = key |
| 93 | new_pairs(n + 1)%value%value_type = JSON_STRING |
| 94 | new_pairs(n + 1)%value%string_value = value |
| 95 | |
| 96 | deallocate(obj%object_value%pairs) |
| 97 | obj%object_value%pairs = new_pairs |
| 98 | obj%object_value%count = n + 1 |
| 99 | end subroutine json_add_string |
| 100 | |
| 101 | subroutine json_add_number(obj, key, value) |
| 102 | type(json_value_t), intent(inout) :: obj |
| 103 | character(len=*), intent(in) :: key |
| 104 | real(real64), intent(in) :: value |
| 105 | type(json_pair_t), allocatable :: new_pairs(:) |
| 106 | integer :: n |
| 107 | |
| 108 | if (obj%value_type /= JSON_OBJECT) return |
| 109 | |
| 110 | n = obj%object_value%count |
| 111 | allocate(new_pairs(n + 1)) |
| 112 | |
| 113 | if (n > 0) new_pairs(1:n) = obj%object_value%pairs |
| 114 | |
| 115 | new_pairs(n + 1)%key = key |
| 116 | new_pairs(n + 1)%value%value_type = JSON_NUMBER |
| 117 | new_pairs(n + 1)%value%number_value = value |
| 118 | |
| 119 | deallocate(obj%object_value%pairs) |
| 120 | obj%object_value%pairs = new_pairs |
| 121 | obj%object_value%count = n + 1 |
| 122 | end subroutine json_add_number |
| 123 | |
| 124 | subroutine json_add_bool(obj, key, value) |
| 125 | type(json_value_t), intent(inout) :: obj |
| 126 | character(len=*), intent(in) :: key |
| 127 | logical, intent(in) :: value |
| 128 | type(json_pair_t), allocatable :: new_pairs(:) |
| 129 | integer :: n |
| 130 | |
| 131 | if (obj%value_type /= JSON_OBJECT) return |
| 132 | |
| 133 | n = obj%object_value%count |
| 134 | allocate(new_pairs(n + 1)) |
| 135 | |
| 136 | if (n > 0) new_pairs(1:n) = obj%object_value%pairs |
| 137 | |
| 138 | new_pairs(n + 1)%key = key |
| 139 | new_pairs(n + 1)%value%value_type = JSON_BOOL |
| 140 | new_pairs(n + 1)%value%bool_value = value |
| 141 | |
| 142 | deallocate(obj%object_value%pairs) |
| 143 | obj%object_value%pairs = new_pairs |
| 144 | obj%object_value%count = n + 1 |
| 145 | end subroutine json_add_bool |
| 146 | |
| 147 | subroutine json_add_null(obj, key) |
| 148 | type(json_value_t), intent(inout) :: obj |
| 149 | character(len=*), intent(in) :: key |
| 150 | type(json_pair_t), allocatable :: new_pairs(:) |
| 151 | integer :: n |
| 152 | |
| 153 | if (obj%value_type /= JSON_OBJECT) return |
| 154 | |
| 155 | n = obj%object_value%count |
| 156 | allocate(new_pairs(n + 1)) |
| 157 | |
| 158 | if (n > 0) new_pairs(1:n) = obj%object_value%pairs |
| 159 | |
| 160 | new_pairs(n + 1)%key = key |
| 161 | new_pairs(n + 1)%value%value_type = JSON_NULL |
| 162 | |
| 163 | deallocate(obj%object_value%pairs) |
| 164 | obj%object_value%pairs = new_pairs |
| 165 | obj%object_value%count = n + 1 |
| 166 | end subroutine json_add_null |
| 167 | |
| 168 | subroutine json_add_object(obj, key, child) |
| 169 | type(json_value_t), intent(inout) :: obj |
| 170 | character(len=*), intent(in) :: key |
| 171 | type(json_value_t), intent(in) :: child |
| 172 | type(json_pair_t), allocatable :: new_pairs(:) |
| 173 | integer :: n |
| 174 | |
| 175 | if (obj%value_type /= JSON_OBJECT) return |
| 176 | if (child%value_type /= JSON_OBJECT) return |
| 177 | |
| 178 | n = obj%object_value%count |
| 179 | allocate(new_pairs(n + 1)) |
| 180 | |
| 181 | if (n > 0) new_pairs(1:n) = obj%object_value%pairs |
| 182 | |
| 183 | new_pairs(n + 1)%key = key |
| 184 | new_pairs(n + 1)%value = child |
| 185 | |
| 186 | deallocate(obj%object_value%pairs) |
| 187 | obj%object_value%pairs = new_pairs |
| 188 | obj%object_value%count = n + 1 |
| 189 | end subroutine json_add_object |
| 190 | |
| 191 | subroutine json_add_array(obj, key, arr) |
| 192 | type(json_value_t), intent(inout) :: obj |
| 193 | character(len=*), intent(in) :: key |
| 194 | type(json_value_t), intent(in) :: arr |
| 195 | type(json_pair_t), allocatable :: new_pairs(:) |
| 196 | integer :: n |
| 197 | |
| 198 | if (obj%value_type /= JSON_OBJECT) return |
| 199 | if (arr%value_type /= JSON_ARRAY) return |
| 200 | |
| 201 | n = obj%object_value%count |
| 202 | allocate(new_pairs(n + 1)) |
| 203 | |
| 204 | if (n > 0) new_pairs(1:n) = obj%object_value%pairs |
| 205 | |
| 206 | new_pairs(n + 1)%key = key |
| 207 | new_pairs(n + 1)%value = arr |
| 208 | |
| 209 | deallocate(obj%object_value%pairs) |
| 210 | obj%object_value%pairs = new_pairs |
| 211 | obj%object_value%count = n + 1 |
| 212 | end subroutine json_add_array |
| 213 | |
| 214 | subroutine json_add_value(obj, key, value) |
| 215 | type(json_value_t), intent(inout) :: obj |
| 216 | character(len=*), intent(in) :: key |
| 217 | type(json_value_t), intent(in) :: value |
| 218 | type(json_pair_t), dimension(:), allocatable :: new_pairs |
| 219 | integer :: n |
| 220 | |
| 221 | if (obj%value_type /= JSON_OBJECT) return |
| 222 | if (.not. associated(obj%object_value)) return |
| 223 | |
| 224 | n = obj%object_value%count |
| 225 | allocate(new_pairs(n + 1)) |
| 226 | |
| 227 | if (n > 0) new_pairs(1:n) = obj%object_value%pairs |
| 228 | |
| 229 | new_pairs(n + 1)%key = key |
| 230 | new_pairs(n + 1)%value = value |
| 231 | |
| 232 | deallocate(obj%object_value%pairs) |
| 233 | obj%object_value%pairs = new_pairs |
| 234 | obj%object_value%count = n + 1 |
| 235 | end subroutine json_add_value |
| 236 | |
| 237 | subroutine json_array_add_element(arr, element) |
| 238 | type(json_value_t), intent(inout) :: arr |
| 239 | type(json_value_t), intent(in) :: element |
| 240 | type(json_value_t), dimension(:), allocatable :: new_elements |
| 241 | integer :: n |
| 242 | |
| 243 | if (arr%value_type /= JSON_ARRAY) return |
| 244 | if (.not. associated(arr%array_value)) return |
| 245 | |
| 246 | n = arr%array_value%count |
| 247 | allocate(new_elements(n + 1)) |
| 248 | |
| 249 | if (n > 0) new_elements(1:n) = arr%array_value%elements |
| 250 | |
| 251 | new_elements(n + 1) = element |
| 252 | |
| 253 | deallocate(arr%array_value%elements) |
| 254 | arr%array_value%elements = new_elements |
| 255 | arr%array_value%count = n + 1 |
| 256 | end subroutine json_array_add_element |
| 257 | |
| 258 | recursive function json_stringify(value) result(str) |
| 259 | type(json_value_t), intent(in) :: value |
| 260 | character(len=:), allocatable :: str |
| 261 | |
| 262 | select case(value%value_type) |
| 263 | case(JSON_NULL) |
| 264 | str = "null" |
| 265 | case(JSON_BOOL) |
| 266 | if (value%bool_value) then |
| 267 | str = "true" |
| 268 | else |
| 269 | str = "false" |
| 270 | end if |
| 271 | case(JSON_NUMBER) |
| 272 | str = number_to_string(value%number_value) |
| 273 | case(JSON_STRING) |
| 274 | str = '"' // escape_string(value%string_value) // '"' |
| 275 | case(JSON_OBJECT) |
| 276 | str = object_to_string(value%object_value) |
| 277 | case(JSON_ARRAY) |
| 278 | str = array_to_string(value%array_value) |
| 279 | end select |
| 280 | end function json_stringify |
| 281 | |
| 282 | recursive function object_to_string(obj) result(str) |
| 283 | type(json_object_t), pointer, intent(in) :: obj |
| 284 | character(len=:), allocatable :: str |
| 285 | integer :: i |
| 286 | |
| 287 | if (.not. associated(obj)) then |
| 288 | str = "null" |
| 289 | return |
| 290 | end if |
| 291 | |
| 292 | str = "{" |
| 293 | do i = 1, obj%count |
| 294 | if (i > 1) str = str // "," |
| 295 | str = str // '"' // obj%pairs(i)%key // '":' // & |
| 296 | json_stringify(obj%pairs(i)%value) |
| 297 | end do |
| 298 | str = str // "}" |
| 299 | end function object_to_string |
| 300 | |
| 301 | recursive function array_to_string(arr) result(str) |
| 302 | type(json_array_t), pointer, intent(in) :: arr |
| 303 | character(len=:), allocatable :: str |
| 304 | integer :: i |
| 305 | |
| 306 | if (.not. associated(arr)) then |
| 307 | str = "null" |
| 308 | return |
| 309 | end if |
| 310 | |
| 311 | str = "[" |
| 312 | do i = 1, arr%count |
| 313 | if (i > 1) str = str // "," |
| 314 | str = str // json_stringify(arr%elements(i)) |
| 315 | end do |
| 316 | str = str // "]" |
| 317 | end function array_to_string |
| 318 | |
| 319 | function escape_string(str) result(escaped) |
| 320 | character(len=*), intent(in) :: str |
| 321 | character(len=:), allocatable :: escaped |
| 322 | integer :: i |
| 323 | character :: ch |
| 324 | |
| 325 | escaped = "" |
| 326 | do i = 1, len(str) |
| 327 | ch = str(i:i) |
| 328 | select case(ch) |
| 329 | case('"') |
| 330 | escaped = escaped // '\"' |
| 331 | case('\') |
| 332 | escaped = escaped // '\\' |
| 333 | case(char(8)) ! backspace |
| 334 | escaped = escaped // '\b' |
| 335 | case(char(12)) ! form feed |
| 336 | escaped = escaped // '\f' |
| 337 | case(char(10)) ! newline |
| 338 | escaped = escaped // '\n' |
| 339 | case(char(13)) ! carriage return |
| 340 | escaped = escaped // '\r' |
| 341 | case(char(9)) ! tab |
| 342 | escaped = escaped // '\t' |
| 343 | case default |
| 344 | escaped = escaped // ch |
| 345 | end select |
| 346 | end do |
| 347 | end function escape_string |
| 348 | |
| 349 | ! Unescape JSON string escape sequences (inverse of escape_string) |
| 350 | function unescape_string(str) result(unescaped) |
| 351 | character(len=*), intent(in) :: str |
| 352 | character(len=:), allocatable :: unescaped |
| 353 | integer :: i, n |
| 354 | |
| 355 | unescaped = "" |
| 356 | n = len(str) |
| 357 | i = 1 |
| 358 | do while (i <= n) |
| 359 | if (str(i:i) == '\' .and. i < n) then |
| 360 | select case(str(i+1:i+1)) |
| 361 | case('"') |
| 362 | unescaped = unescaped // '"' |
| 363 | case('\') |
| 364 | unescaped = unescaped // '\' |
| 365 | case('b') |
| 366 | unescaped = unescaped // char(8) ! backspace |
| 367 | case('f') |
| 368 | unescaped = unescaped // char(12) ! form feed |
| 369 | case('n') |
| 370 | unescaped = unescaped // char(10) ! newline |
| 371 | case('r') |
| 372 | unescaped = unescaped // char(13) ! carriage return |
| 373 | case('t') |
| 374 | unescaped = unescaped // char(9) ! tab |
| 375 | case default |
| 376 | ! Unknown escape, keep as-is |
| 377 | unescaped = unescaped // str(i:i+1) |
| 378 | end select |
| 379 | i = i + 2 |
| 380 | else |
| 381 | unescaped = unescaped // str(i:i) |
| 382 | i = i + 1 |
| 383 | end if |
| 384 | end do |
| 385 | end function unescape_string |
| 386 | |
| 387 | function number_to_string(num) result(str) |
| 388 | real(real64), intent(in) :: num |
| 389 | character(len=:), allocatable :: str |
| 390 | character(len=32) :: buffer |
| 391 | |
| 392 | if (num == int(num)) then |
| 393 | write(buffer, '(i0)') int(num) |
| 394 | else |
| 395 | write(buffer, '(f0.6)') num |
| 396 | end if |
| 397 | str = trim(buffer) |
| 398 | end function number_to_string |
| 399 | |
| 400 | function json_has_key(obj, key) result(has) |
| 401 | type(json_value_t), intent(in) :: obj |
| 402 | character(len=*), intent(in) :: key |
| 403 | logical :: has |
| 404 | integer :: i |
| 405 | |
| 406 | has = .false. |
| 407 | if (obj%value_type /= JSON_OBJECT) return |
| 408 | if (.not. associated(obj%object_value)) return |
| 409 | |
| 410 | do i = 1, obj%object_value%count |
| 411 | if (obj%object_value%pairs(i)%key == key) then |
| 412 | has = .true. |
| 413 | return |
| 414 | end if |
| 415 | end do |
| 416 | end function json_has_key |
| 417 | |
| 418 | function json_get_string(obj, key, default) result(value) |
| 419 | type(json_value_t), intent(in) :: obj |
| 420 | character(len=*), intent(in) :: key |
| 421 | character(len=*), intent(in), optional :: default |
| 422 | character(len=:), allocatable :: value |
| 423 | integer :: i |
| 424 | |
| 425 | if (present(default)) then |
| 426 | value = default |
| 427 | else |
| 428 | value = "" |
| 429 | end if |
| 430 | |
| 431 | if (obj%value_type /= JSON_OBJECT) return |
| 432 | if (.not. associated(obj%object_value)) return |
| 433 | |
| 434 | do i = 1, obj%object_value%count |
| 435 | if (obj%object_value%pairs(i)%key == key) then |
| 436 | if (obj%object_value%pairs(i)%value%value_type == JSON_STRING) then |
| 437 | value = obj%object_value%pairs(i)%value%string_value |
| 438 | end if |
| 439 | return |
| 440 | end if |
| 441 | end do |
| 442 | end function json_get_string |
| 443 | |
| 444 | function json_get_number(obj, key, default) result(value) |
| 445 | type(json_value_t), intent(in) :: obj |
| 446 | character(len=*), intent(in) :: key |
| 447 | real(real64), intent(in), optional :: default |
| 448 | real(real64) :: value |
| 449 | integer :: i |
| 450 | |
| 451 | if (present(default)) then |
| 452 | value = default |
| 453 | else |
| 454 | value = 0.0 |
| 455 | end if |
| 456 | |
| 457 | if (obj%value_type /= JSON_OBJECT) return |
| 458 | if (.not. associated(obj%object_value)) return |
| 459 | |
| 460 | do i = 1, obj%object_value%count |
| 461 | if (obj%object_value%pairs(i)%key == key) then |
| 462 | if (obj%object_value%pairs(i)%value%value_type == JSON_NUMBER) then |
| 463 | value = obj%object_value%pairs(i)%value%number_value |
| 464 | end if |
| 465 | return |
| 466 | end if |
| 467 | end do |
| 468 | end function json_get_number |
| 469 | |
| 470 | function json_get_bool(obj, key, default) result(value) |
| 471 | type(json_value_t), intent(in) :: obj |
| 472 | character(len=*), intent(in) :: key |
| 473 | logical, intent(in), optional :: default |
| 474 | logical :: value |
| 475 | integer :: i |
| 476 | |
| 477 | if (present(default)) then |
| 478 | value = default |
| 479 | else |
| 480 | value = .false. |
| 481 | end if |
| 482 | |
| 483 | if (obj%value_type /= JSON_OBJECT) return |
| 484 | if (.not. associated(obj%object_value)) return |
| 485 | |
| 486 | do i = 1, obj%object_value%count |
| 487 | if (obj%object_value%pairs(i)%key == key) then |
| 488 | if (obj%object_value%pairs(i)%value%value_type == JSON_BOOL) then |
| 489 | value = obj%object_value%pairs(i)%value%bool_value |
| 490 | end if |
| 491 | return |
| 492 | end if |
| 493 | end do |
| 494 | end function json_get_bool |
| 495 | |
| 496 | function json_get_object(obj, key) result(value) |
| 497 | type(json_value_t), intent(in) :: obj |
| 498 | character(len=*), intent(in) :: key |
| 499 | type(json_value_t) :: value |
| 500 | integer :: i |
| 501 | |
| 502 | value%value_type = JSON_NULL |
| 503 | |
| 504 | if (obj%value_type /= JSON_OBJECT) return |
| 505 | if (.not. associated(obj%object_value)) return |
| 506 | |
| 507 | do i = 1, obj%object_value%count |
| 508 | if (obj%object_value%pairs(i)%key == key) then |
| 509 | if (obj%object_value%pairs(i)%value%value_type == JSON_OBJECT) then |
| 510 | value = obj%object_value%pairs(i)%value |
| 511 | end if |
| 512 | return |
| 513 | end if |
| 514 | end do |
| 515 | end function json_get_object |
| 516 | |
| 517 | function json_get_array(obj, key) result(value) |
| 518 | type(json_value_t), intent(in) :: obj |
| 519 | character(len=*), intent(in) :: key |
| 520 | type(json_value_t) :: value |
| 521 | integer :: i |
| 522 | |
| 523 | value%value_type = JSON_NULL |
| 524 | |
| 525 | if (obj%value_type /= JSON_OBJECT) return |
| 526 | if (.not. associated(obj%object_value)) return |
| 527 | |
| 528 | do i = 1, obj%object_value%count |
| 529 | if (obj%object_value%pairs(i)%key == key) then |
| 530 | if (obj%object_value%pairs(i)%value%value_type == JSON_ARRAY) then |
| 531 | value = obj%object_value%pairs(i)%value |
| 532 | end if |
| 533 | return |
| 534 | end if |
| 535 | end do |
| 536 | end function json_get_array |
| 537 | |
| 538 | ! Get any JSON value by key (regardless of type) - for LSP data field |
| 539 | function json_get_value(obj, key) result(value) |
| 540 | type(json_value_t), intent(in) :: obj |
| 541 | character(len=*), intent(in) :: key |
| 542 | type(json_value_t) :: value |
| 543 | integer :: i |
| 544 | |
| 545 | value%value_type = JSON_NULL |
| 546 | |
| 547 | if (obj%value_type /= JSON_OBJECT) return |
| 548 | if (.not. associated(obj%object_value)) return |
| 549 | |
| 550 | do i = 1, obj%object_value%count |
| 551 | if (obj%object_value%pairs(i)%key == key) then |
| 552 | value = obj%object_value%pairs(i)%value |
| 553 | return |
| 554 | end if |
| 555 | end do |
| 556 | end function json_get_value |
| 557 | |
| 558 | ! Simple JSON parser (basic implementation) |
| 559 | function json_parse(str) result(value) |
| 560 | character(len=*), intent(in) :: str |
| 561 | type(json_value_t) :: value |
| 562 | integer :: pos |
| 563 | |
| 564 | pos = 1 |
| 565 | call skip_whitespace(str, pos) |
| 566 | value = parse_value(str, pos) |
| 567 | end function json_parse |
| 568 | |
| 569 | recursive function parse_value(str, pos) result(value) |
| 570 | character(len=*), intent(in) :: str |
| 571 | integer, intent(inout) :: pos |
| 572 | type(json_value_t) :: value |
| 573 | |
| 574 | call skip_whitespace(str, pos) |
| 575 | |
| 576 | if (pos > len(str)) then |
| 577 | value%value_type = JSON_NULL |
| 578 | return |
| 579 | end if |
| 580 | |
| 581 | select case(str(pos:pos)) |
| 582 | case('{') |
| 583 | value = parse_object(str, pos) |
| 584 | case('[') |
| 585 | value = parse_array(str, pos) |
| 586 | case('"') |
| 587 | value = parse_string(str, pos) |
| 588 | case('t', 'f') ! true or false |
| 589 | value = parse_bool(str, pos) |
| 590 | case('n') ! null |
| 591 | value = parse_null(str, pos) |
| 592 | case default |
| 593 | ! Try to parse as number |
| 594 | value = parse_number(str, pos) |
| 595 | end select |
| 596 | end function parse_value |
| 597 | |
| 598 | recursive function parse_object(str, pos) result(obj) |
| 599 | character(len=*), intent(in) :: str |
| 600 | integer, intent(inout) :: pos |
| 601 | type(json_value_t) :: obj |
| 602 | character(len=:), allocatable :: key |
| 603 | type(json_value_t) :: value |
| 604 | logical :: first_pair |
| 605 | |
| 606 | obj = json_create_object() |
| 607 | pos = pos + 1 ! skip '{' |
| 608 | first_pair = .true. |
| 609 | |
| 610 | call skip_whitespace(str, pos) |
| 611 | |
| 612 | ! Handle empty object |
| 613 | if (pos <= len(str) .and. str(pos:pos) == '}') then |
| 614 | pos = pos + 1 |
| 615 | return |
| 616 | end if |
| 617 | |
| 618 | ! Parse key-value pairs |
| 619 | do while (pos <= len(str)) |
| 620 | ! Skip comma if not first pair |
| 621 | if (.not. first_pair) then |
| 622 | if (str(pos:pos) /= ',') exit |
| 623 | pos = pos + 1 |
| 624 | call skip_whitespace(str, pos) |
| 625 | end if |
| 626 | first_pair = .false. |
| 627 | |
| 628 | ! Check for end of object |
| 629 | if (pos > len(str)) exit |
| 630 | if (str(pos:pos) == '}') then |
| 631 | pos = pos + 1 |
| 632 | exit |
| 633 | end if |
| 634 | |
| 635 | ! Parse key (must be a string) |
| 636 | if (str(pos:pos) /= '"') exit |
| 637 | key = parse_object_key(str, pos) |
| 638 | |
| 639 | call skip_whitespace(str, pos) |
| 640 | |
| 641 | ! Expect colon |
| 642 | if (pos > len(str) .or. str(pos:pos) /= ':') exit |
| 643 | pos = pos + 1 |
| 644 | |
| 645 | call skip_whitespace(str, pos) |
| 646 | |
| 647 | ! Parse value |
| 648 | value = parse_value(str, pos) |
| 649 | |
| 650 | ! Add key-value pair to object |
| 651 | call json_add_value(obj, key, value) |
| 652 | |
| 653 | call skip_whitespace(str, pos) |
| 654 | |
| 655 | ! Check for end of object |
| 656 | if (pos <= len(str) .and. str(pos:pos) == '}') then |
| 657 | pos = pos + 1 |
| 658 | exit |
| 659 | end if |
| 660 | end do |
| 661 | end function parse_object |
| 662 | |
| 663 | function parse_object_key(str, pos) result(key) |
| 664 | character(len=*), intent(in) :: str |
| 665 | integer, intent(inout) :: pos |
| 666 | character(len=:), allocatable :: key |
| 667 | integer :: start_pos |
| 668 | |
| 669 | pos = pos + 1 ! skip opening '"' |
| 670 | start_pos = pos |
| 671 | |
| 672 | ! Find closing '"' (ignoring escaped quotes) |
| 673 | do while (pos <= len(str)) |
| 674 | if (str(pos:pos) == '\' .and. pos < len(str)) then |
| 675 | pos = pos + 2 ! skip escaped character |
| 676 | else if (str(pos:pos) == '"') then |
| 677 | if (pos > start_pos) then |
| 678 | key = str(start_pos:pos-1) |
| 679 | else |
| 680 | key = "" |
| 681 | end if |
| 682 | pos = pos + 1 ! skip closing '"' |
| 683 | return |
| 684 | else |
| 685 | pos = pos + 1 |
| 686 | end if |
| 687 | end do |
| 688 | |
| 689 | ! If we get here, string was not terminated |
| 690 | key = "" |
| 691 | end function parse_object_key |
| 692 | |
| 693 | recursive function parse_array(str, pos) result(arr) |
| 694 | character(len=*), intent(in) :: str |
| 695 | integer, intent(inout) :: pos |
| 696 | type(json_value_t) :: arr |
| 697 | type(json_value_t) :: element |
| 698 | logical :: first_element |
| 699 | |
| 700 | arr = json_create_array() |
| 701 | pos = pos + 1 ! skip '[' |
| 702 | first_element = .true. |
| 703 | |
| 704 | call skip_whitespace(str, pos) |
| 705 | |
| 706 | ! Handle empty array |
| 707 | if (pos <= len(str) .and. str(pos:pos) == ']') then |
| 708 | pos = pos + 1 |
| 709 | return |
| 710 | end if |
| 711 | |
| 712 | ! Parse elements |
| 713 | do while (pos <= len(str)) |
| 714 | ! Skip comma if not first element |
| 715 | if (.not. first_element) then |
| 716 | if (str(pos:pos) /= ',') exit |
| 717 | pos = pos + 1 |
| 718 | call skip_whitespace(str, pos) |
| 719 | end if |
| 720 | first_element = .false. |
| 721 | |
| 722 | ! Check for end of array |
| 723 | if (pos > len(str)) exit |
| 724 | if (str(pos:pos) == ']') then |
| 725 | pos = pos + 1 |
| 726 | exit |
| 727 | end if |
| 728 | |
| 729 | ! Parse element |
| 730 | element = parse_value(str, pos) |
| 731 | |
| 732 | ! Add element to array |
| 733 | call json_array_add_element(arr, element) |
| 734 | |
| 735 | call skip_whitespace(str, pos) |
| 736 | |
| 737 | ! Check for end of array |
| 738 | if (pos <= len(str) .and. str(pos:pos) == ']') then |
| 739 | pos = pos + 1 |
| 740 | exit |
| 741 | end if |
| 742 | end do |
| 743 | end function parse_array |
| 744 | |
| 745 | function parse_string(str, pos) result(value) |
| 746 | character(len=*), intent(in) :: str |
| 747 | integer, intent(inout) :: pos |
| 748 | type(json_value_t) :: value |
| 749 | integer :: start_pos |
| 750 | |
| 751 | value%value_type = JSON_STRING |
| 752 | pos = pos + 1 ! skip opening '"' |
| 753 | start_pos = pos |
| 754 | |
| 755 | ! Find closing '"' (ignoring escaped quotes) |
| 756 | do while (pos <= len(str)) |
| 757 | if (str(pos:pos) == '\' .and. pos < len(str)) then |
| 758 | pos = pos + 2 ! skip escaped character |
| 759 | else if (str(pos:pos) == '"') then |
| 760 | ! Unescape the string (convert \n to newline, etc.) |
| 761 | value%string_value = unescape_string(str(start_pos:pos-1)) |
| 762 | pos = pos + 1 ! skip closing '"' |
| 763 | return |
| 764 | else |
| 765 | pos = pos + 1 |
| 766 | end if |
| 767 | end do |
| 768 | |
| 769 | value%string_value = unescape_string(str(start_pos:)) |
| 770 | end function parse_string |
| 771 | |
| 772 | function parse_number(str, pos) result(value) |
| 773 | character(len=*), intent(in) :: str |
| 774 | integer, intent(inout) :: pos |
| 775 | type(json_value_t) :: value |
| 776 | integer :: start_pos |
| 777 | character :: ch |
| 778 | |
| 779 | value%value_type = JSON_NUMBER |
| 780 | start_pos = pos |
| 781 | |
| 782 | ! Parse sign |
| 783 | if (pos <= len(str)) then |
| 784 | ch = str(pos:pos) |
| 785 | if (ch == '-' .or. ch == '+') pos = pos + 1 |
| 786 | end if |
| 787 | |
| 788 | ! Parse digits |
| 789 | do while (pos <= len(str)) |
| 790 | ch = str(pos:pos) |
| 791 | if ((ch >= '0' .and. ch <= '9') .or. ch == '.' .or. & |
| 792 | ch == 'e' .or. ch == 'E' .or. ch == '+' .or. ch == '-') then |
| 793 | pos = pos + 1 |
| 794 | else |
| 795 | exit |
| 796 | end if |
| 797 | end do |
| 798 | |
| 799 | read(str(start_pos:pos-1), *) value%number_value |
| 800 | end function parse_number |
| 801 | |
| 802 | function parse_bool(str, pos) result(value) |
| 803 | character(len=*), intent(in) :: str |
| 804 | integer, intent(inout) :: pos |
| 805 | type(json_value_t) :: value |
| 806 | |
| 807 | value%value_type = JSON_BOOL |
| 808 | |
| 809 | if (str(pos:min(pos+3, len(str))) == 'true') then |
| 810 | value%bool_value = .true. |
| 811 | pos = pos + 4 |
| 812 | else if (str(pos:min(pos+4, len(str))) == 'false') then |
| 813 | value%bool_value = .false. |
| 814 | pos = pos + 5 |
| 815 | end if |
| 816 | end function parse_bool |
| 817 | |
| 818 | function parse_null(str, pos) result(value) |
| 819 | character(len=*), intent(in) :: str |
| 820 | integer, intent(inout) :: pos |
| 821 | type(json_value_t) :: value |
| 822 | |
| 823 | value%value_type = JSON_NULL |
| 824 | if (str(pos:min(pos+3, len(str))) == 'null') then |
| 825 | pos = pos + 4 |
| 826 | end if |
| 827 | end function parse_null |
| 828 | |
| 829 | subroutine skip_whitespace(str, pos) |
| 830 | character(len=*), intent(in) :: str |
| 831 | integer, intent(inout) :: pos |
| 832 | |
| 833 | do while (pos <= len(str)) |
| 834 | select case(str(pos:pos)) |
| 835 | case(' ', char(9), char(10), char(13)) |
| 836 | pos = pos + 1 |
| 837 | case default |
| 838 | return |
| 839 | end select |
| 840 | end do |
| 841 | end subroutine skip_whitespace |
| 842 | |
| 843 | ! Get the size of a JSON array |
| 844 | function json_array_size(arr) result(size) |
| 845 | type(json_value_t), intent(in) :: arr |
| 846 | integer :: size |
| 847 | |
| 848 | size = 0 |
| 849 | if (arr%value_type == JSON_ARRAY .and. associated(arr%array_value)) then |
| 850 | size = arr%array_value%count |
| 851 | end if |
| 852 | end function json_array_size |
| 853 | |
| 854 | ! Get an element from a JSON array by index (0-based) |
| 855 | function json_get_array_element(arr, index) result(element) |
| 856 | type(json_value_t), intent(in) :: arr |
| 857 | integer, intent(in) :: index |
| 858 | type(json_value_t) :: element |
| 859 | |
| 860 | element%value_type = JSON_NULL |
| 861 | |
| 862 | if (arr%value_type == JSON_ARRAY .and. associated(arr%array_value)) then |
| 863 | if (index >= 0 .and. index < arr%array_value%count) then |
| 864 | element = arr%array_value%elements(index + 1) ! Convert to 1-based |
| 865 | end if |
| 866 | end if |
| 867 | end function json_get_array_element |
| 868 | |
| 869 | end module json_module |