/* vim: set et ts=3 sw=3 sts=3 ft=c:
 *
 * Copyright (C) 2021 Christopher Snowhill.  All rights reserved.
 * https://github.com/kode54/sflist
 * https://gist.github.com/kode54/a7bb01a0db3f2e996145b77f0ca510d5
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <ctype.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <json-builder.h>

#include "sflist.h"

#ifndef PRId64
#ifdef _MSC_VER
#define PRId64 "I64d"
#else
#define PRId64 "lld"
#endif
#endif

/* Extras needed */

static int json_equal(const json_value *a, const json_value *b);

static int json_equal_array(const json_value *a, const json_value *b) {
	unsigned int i, j;

	if(a->u.array.length != b->u.array.length) return 0;

	for(i = 0, j = a->u.array.length; i < j; ++i) {
		if(!json_equal(a->u.array.values[i], b->u.array.values[i]))
			return 0;
	}

	return 1;
}

static int json_equal_object(const json_value *a, const json_value *b) {
	unsigned int i, j;

	if(a->u.object.length != b->u.object.length) return 0;

	for(i = 0, j = a->u.object.length; i < j; ++i) {
		if(strcmp(a->u.object.values[i].name, b->u.object.values[i].name))
			return 0;
		if(!json_equal(a->u.object.values[i].value, b->u.object.values[i].value))
			return 0;
	}

	return 1;
}

static int json_equal(const json_value *a, const json_value *b) {
	if(a->type != b->type) return 0;

	switch(a->type) {
		case json_none:
		case json_null:
			return 1;

		case json_integer:
			return a->u.integer == b->u.integer;

		case json_double:
			return a->u.dbl == b->u.dbl;

		case json_boolean:
			return !a->u.boolean == !b->u.boolean;

		case json_string:
			return !strcmp(a->u.string.ptr, b->u.string.ptr);

		case json_array:
			return json_equal_array(a, b);

		case json_object:
			return json_equal_object(a, b);
	}

	return 0;
}

static int json_signum(double val) {
	return (val > 0.0) - (val < 0.0);
}

#define json_compare_invalid -1000

static int json_compare(const json_value *a, const json_value *b) {
	if(a->type != b->type) return json_compare_invalid;

	switch(a->type) {
		case json_none:
		case json_null:
			return 0;

		case json_integer:
			return (int)(a->u.integer - b->u.integer);

		case json_double:
			return json_signum(a->u.dbl - b->u.dbl);

		case json_boolean:
			return !!a->u.boolean - !!b->u.boolean;

		case json_string:
			return strcmp(a->u.string.ptr, b->u.string.ptr);

		case json_array:
		case json_object:
			return json_compare_invalid;
	}

	return json_compare_invalid;
}

static int json_array_contains_value(const json_value *array, const json_value *value) {
	unsigned int i, j;

	for(i = 0, j = array->u.array.length; i < j; ++i) {
		if(json_equal(array->u.array.values[i], value))
			return 1;
	}

	return 0;
}

json_value *json_array_merge(json_value *arrayA, json_value *arrayB) {
	unsigned int i, j;

	if(arrayA->type != json_array || arrayB->type != json_array)
		return 0;

	for(i = 0, j = arrayB->u.array.length; i < j; ++i) {
		if(!json_array_contains_value(arrayA, arrayB->u.array.values[i])) {
			json_array_push(arrayA, arrayB->u.array.values[i]);
		}
	}

	json_builder_free(arrayB);

	return arrayA;
}

static int json_compare_callback(const void *a, const void *b) {
	const json_value *aa = (const json_value *)a;
	const json_value *bb = (const json_value *)b;
	return json_compare(aa, bb);
}

json_value *json_array_sort(json_value *array) {
	unsigned int i, j;

	json_type type;

	if(array->type != json_array) return 0;

	if(array->u.array.length < 2) return array;

	type = array->u.array.values[0]->type;

	for(i = 1, j = array->u.array.length; i < j; ++i) {
		if(array->u.array.values[i]->type != type)
			return 0;
	}

	qsort(array->u.array.values, j, sizeof(json_value *), json_compare_callback);

	return array;
}

/* Processing begins */

static size_t sflist_parse_int(const char *in, const char **end) {
	size_t rval = 0;
	while(in < *end) {
		if(isdigit(*in)) {
			rval = (rval * 10) + (*in - '0');
		} else
			break;
		++in;
	}
	*end = in;
	return rval;
}

static double sflist_parse_float(const char *in, const char **end) {
	size_t whole = 0;
	size_t decimal = 0;
	size_t decimal_places = 0;
	double sign = 1.0;
	const char *end_orig = *end;
	const char *ptr = in;
	if(*ptr == '-') {
		++ptr;
		sign = -1.0;
	}
	whole = sflist_parse_int(ptr, end);
	if(*end == ptr || (**end != '.' && *end < end_orig)) {
		*end = in;
		return 0.0;
	}
	if(*end < end_orig) {
		ptr = *end + 1;
		*end = end_orig;
		decimal = sflist_parse_int(ptr, end);
		if(*end == ptr || *end < end_orig) {
			*end = in;
			return 0.0;
		}
		decimal_places = *end - ptr;
	}
	return (((double)whole) + (((double)decimal) / pow(10.0, (double)decimal_places))) * sign;
}

static json_value *sflist_load_v1(const char *sflist, size_t size, char *error_buf) {
	json_value *rval = 0;

	json_value *arr = json_array_new(0);

	json_value *channels = 0;
	json_value *patchMappings = 0;
	double gain = 0.0;

	const char *ptr = sflist;
	const char *end = sflist + size;

	unsigned int cur_line = 0;

	while(ptr < end) {
		const char *line_start = ptr;
		json_value *obj = 0;
		const char *path = 0;
		const char *pipe = 0;
		const char *lend = ptr;
		++cur_line;
		while(lend < end && *lend && *lend != '\r' && *lend != '\n') {
			if(*lend == '|')
				pipe = lend;
			++lend;
		}
		if(pipe)
			path = pipe + 1;
		else
			path = ptr;
		if(pipe) {
			while(ptr < pipe) {
				char c;
				const char *fend = ptr;
				const char *vend;
				while(fend < pipe && *fend != '&') ++fend;
				vend = fend;
				switch(c = *ptr++) {
					case '&':
						continue;

					case 'c': {
						json_value *this_channels;
						size_t channel_low = sflist_parse_int(ptr, &vend);
						size_t channel_high = 0;
						size_t i;
						if(vend == ptr || (*vend != '-' && *vend != '&' && *vend != '|')) {
							sprintf(error_buf, "Invalid channel number (%u:%u)", cur_line, (int)(vend - line_start + 1));
							goto error;
						}
						if(*vend != '-')
							channel_high = channel_low;
						else {
							ptr = vend + 1;
							vend = fend;
							channel_high = sflist_parse_int(ptr, &vend);
							if(vend == ptr || (*vend != '&' && *vend != '|')) {
								sprintf(error_buf, "Invalid channel range end value (%u:%u)", cur_line, (int)(vend - line_start + 1));
								goto error;
							}
						}
						if(!channels)
							channels = json_array_new(0);
						this_channels = json_array_new(0);
						for(i = channel_low; i <= channel_high; ++i)
							json_array_push(this_channels, json_integer_new(i));
						channels = json_array_merge(channels, this_channels);
						ptr = fend;
					} break;

					case 'p': {
						json_value *mapping = 0;
						json_value *mapping_destination = 0;
						json_value *mapping_source = 0;

						long source_bank = -1;
						long source_program = -1;
						long dest_bank = -1;
						long dest_program = -1;

						size_t val = sflist_parse_int(ptr, &vend);
						if(vend == ptr || (*vend != '=' && *vend != ',' && *vend != '|')) {
							sprintf(error_buf, "Invalid preset number (%u:%u)", cur_line, (int)(vend - line_start + 1));
							goto error;
						}
						dest_program = val;
						if(*vend == ',') {
							dest_bank = val;
							ptr = vend + 1;
							vend = fend;
							val = sflist_parse_int(ptr, &vend);
							if(vend == ptr || (*vend != '=' && *vend != '|')) {
								sprintf(error_buf, "Invalid preset number (%u:%u)", cur_line, (int)(vend - line_start + 1));
								goto error;
							}
							dest_program = val;
						}
						if(*vend == '=') {
							ptr = vend + 1;
							vend = fend;
							val = sflist_parse_int(ptr, &vend);
							if(vend == ptr || (*vend != ',' && *vend != '|')) {
								sprintf(error_buf, "Invalid preset number (%u:%u)", cur_line, (int)(vend - line_start + 1));
								goto error;
							}
							source_program = val;
							if(*vend == ',') {
								source_bank = val;
								ptr = vend + 1;
								vend = fend;
								val = sflist_parse_int(ptr, &vend);
								if(vend == ptr || (*vend != '&' && *vend != '|')) {
									sprintf(error_buf, "Invalid preset number (%u:%u)", cur_line, (int)(vend - line_start + 1));
									goto error;
								}
								source_program = val;
							}
						}

						if(!patchMappings)
							patchMappings = json_array_new(0);
						mapping = json_object_new(0);
						mapping_destination = json_object_new(0);
						if(dest_bank != -1) {
							json_object_push(mapping_destination, "bank", json_integer_new(dest_bank));
						}
						json_object_push(mapping_destination, "program", json_integer_new(dest_program));
						json_object_push(mapping, "destination", mapping_destination);
						if(source_program != -1) {
							mapping_source = json_object_new(0);
							if(source_bank != -1) {
								json_object_push(mapping_source, "bank", json_integer_new(source_bank));
							}
							json_object_push(mapping_source, "program", json_integer_new(source_program));
							json_object_push(mapping, "source", mapping_source);
						}
						json_array_push(patchMappings, mapping);

						ptr = fend;
					} break;

					case 'g': {
						double val = sflist_parse_float(ptr, &vend);
						if(vend == ptr || vend < fend) {
							sprintf(error_buf, "Invalid gain value (%u:%u)", cur_line, (int)(vend - line_start + 1));
							goto error;
						}
						gain = val;
						ptr = fend;
					} break;

					default:
						sprintf(error_buf, "Invalid character in preset '%c' (%u:%u)", c, cur_line, (unsigned int)(ptr - line_start));
						goto error;
				}
			}
		}
		obj = json_object_new(0);
		json_object_push(obj, "fileName", json_string_new_length((unsigned int)(lend - path), path));
		if(gain != 0.0) {
			json_object_push(obj, "gain", json_double_new(gain));
			gain = 0.0;
		}
		if(channels) {
			channels = json_array_sort(channels);
			json_object_push(obj, "channels", channels);
			channels = 0;
		}
		if(patchMappings) {
			json_object_push(obj, "patchMappings", patchMappings);
			patchMappings = 0;
		}

		json_array_push(arr, obj);

		ptr = lend;

		while(ptr < end && (*ptr == '\n' || *ptr == '\r')) ++ptr;
	}

	rval = json_object_new(1);
	json_object_push(rval, "soundFonts", arr);

	return rval;

error:
	if(channels) json_builder_free(channels);
	if(patchMappings) json_builder_free(patchMappings);
	if(arr) json_builder_free(arr);
	return 0;
}

static json_value *sflist_load_v2(const char *sflist, size_t size, char *error) {
	json_value *rval = 0;

	json_settings settings = { 0 };
	settings.value_extra = json_builder_extra;

	rval = json_parse_ex(&settings, sflist, size, error);

	return rval;
}

static const json_value *json_object_item(const json_value *object, const char *name) {
	unsigned int i, j;

	if(object->type != json_object) return &json_value_none;

	for(i = 0, j = object->u.object.length; i < j; ++i) {
		if(!strcmp(object->u.object.values[i].name, name))
			return object->u.object.values[i].value;
	}

	return &json_value_none;
}

static void sflist_process_patchmappings(BASS_MIDI_FONTEX2 *out, BASS_MIDI_FONTEX2 *fontex, const json_value *patchMappings, unsigned int channel, unsigned int channelCount) {
	unsigned int i, j;
	for(i = 0, j = patchMappings->u.array.length; i < j; ++i) {
		json_value *preset = patchMappings->u.array.values[i];
		const json_value *destination = json_object_item(preset, "destination");
		const json_value *source = json_object_item(preset, "source");
		const json_value *destination_bank = json_object_item(destination, "bank");
		const json_value *destination_program = json_object_item(destination, "program");
		const json_value *source_bank = json_object_item(source, "bank");
		const json_value *source_program = json_object_item(source, "program");
		fontex->spreset = (source_program->type == json_none) ? -1 : (int)source_program->u.integer;
		fontex->sbank = (source_bank->type == json_none) ? -1 : (int)source_bank->u.integer;
		fontex->dpreset = (destination_program->type == json_none) ? -1 : (int)destination_program->u.integer;
		fontex->dbank = (destination_bank->type == json_none) ? 0 : (int)destination_bank->u.integer;
		fontex->minchan = channel;
		fontex->numchan = channelCount;
		*out++ = *fontex;
	}
}

static sflist_presets *sflist_process(const json_value *sflist, const char *base_path, char *error_buf) {
#ifdef _WIN32
	wchar_t path16[32768];
#endif
	char path_temp[32768];
	const char *base_path_end = base_path + strlen(base_path) - 1;
	unsigned int presets_to_allocate = 0;
	sflist_presets *rval = calloc(1, sizeof(sflist_presets));
	json_value *arr;
	unsigned int i, j, k, l, preset_number;
	HSOUNDFONT hfont = 0;
	BASS_MIDI_FONTEX2 fontex;

	if(!rval) {
		strcpy(error_buf, "Out of memory");
		goto error;
	}

	if(sflist->type != json_object || sflist->u.object.length != 1 ||
	   strcmp(sflist->u.object.values[0].name, "soundFonts")) {
		if(sflist->type != json_object)
			strcpy(error_buf, "Base JSON item is not an object");
		else if(sflist->u.object.length != 1)
			sprintf(error_buf, "Base JSON object contains unexpected number of items (wanted 1, got %u)", sflist->u.object.length);
		else
			sprintf(error_buf, "Base JSON object contains '%s' object instead of 'soundFonts'", sflist->u.object.values[0].name);
		goto error;
	}

	arr = sflist->u.object.values[0].value;

	if(arr->type != json_array) {
		strcpy(error_buf, "JSON 'soundFonts' object is not an array");
		goto error;
	}

	for(i = 0, j = arr->u.array.length; i < j; ++i) {
		const json_value *obj = arr->u.array.values[i];
		const json_value *path = 0;
		const json_value *gain = 0;
		const json_value *channels = 0;
		const json_value *patchMappings = 0;
		unsigned int patches_needed = 1;
		if(obj->type != json_object) {
			sprintf(error_buf, "soundFont item #%u is not an object", i + 1);
			goto error;
		}
		path = json_object_item(obj, "fileName");
		gain = json_object_item(obj, "gain");
		channels = json_object_item(obj, "channels");
		patchMappings = json_object_item(obj, "patchMappings");
		if(path->type == json_none) {
			sprintf(error_buf, "soundFont item #%u has no 'fileName'", i + 1);
			goto error;
		}
		if(path->type != json_string) {
			sprintf(error_buf, "soundFont item #%u 'fileName' is not a string", i + 1);
			goto error;
		}
		if(gain->type != json_none && gain->type != json_integer && gain->type != json_double) {
			sprintf(error_buf, "soundFont item #%u has an invalid gain value", i + 1);
			goto error;
		}
		if(channels->type != json_none) {
			if(channels->type != json_array) {
				sprintf(error_buf, "soundFont item #%u 'channels' is not an array", i + 1);
				goto error;
			}
			int prevchannel = -1;
			int contiguouschannelsets = 0;
			for(k = 0, l = channels->u.array.length; k < l; ++k) {
				json_value *channel = channels->u.array.values[k];
				if(channel->type != json_integer) {
					sprintf(error_buf, "soundFont item #%u 'channels' #%u is not an integer", i + 1, k + 1);
					goto error;
				}
				if(channel->u.integer < 1 || channel->u.integer > 48) {
					sprintf(error_buf, "soundFont item #%u 'channels' #%u is out of range (wanted 1-48, got %" PRId64 ")", i + 1, k + 1, channel->u.integer);
					goto error;
				}
				if(prevchannel < 0 || channel->u.integer > (prevchannel + 1)) {
					++contiguouschannelsets;
				}
				prevchannel = (int)channel->u.integer;
			}
			patches_needed = contiguouschannelsets;
		}
		if(patchMappings->type != json_none) {
			if(patchMappings->type != json_array) {
				sprintf(error_buf, "soundFont item #%u 'patchMappings' is not an array", i + 1);
				goto error;
			}
			for(k = 0, l = patchMappings->u.array.length; k < l; ++k) {
				unsigned int m, n;
				unsigned int source_found = 0;
				unsigned int destination_found = 0;
				json_value *mapping = patchMappings->u.array.values[k];
				if(mapping->type != json_object) {
					sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u is not an object", i + 1, k + 1);
					goto error;
				}
				for(m = 0, n = mapping->u.object.length; m < n; ++m) {
					unsigned int o, p;
					json_value *item = mapping->u.object.values[m].value;
					const char *name = mapping->u.object.values[m].name;
					unsigned int bank_found = 0;
					unsigned int program_found = 0;
					if(strcmp(name, "source") && strcmp(name, "destination")) {
						sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u contains an invalid '%s' field", i + 1, k + 1, name);
						goto error;
					}
					if(item->type != json_object) {
						sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u '%s' is not an object", i + 1, k + 1, name);
						goto error;
					}
					if(!strcmp(name, "source"))
						++source_found;
					else
						++destination_found;
					for(o = 0, p = item->u.object.length; o < p; ++o) {
						int range_min = 0;
						int range_max = 128;
						json_value *item2 = item->u.object.values[o].value;
						const char *name2 = item->u.object.values[o].name;
						if(strcmp(name2, "bank") && strcmp(name2, "program")) {
							sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u '%s' contains an invalid '%s' field", i + 1, k + 1, name, name2);
							goto error;
						}
						if(item2->type != json_integer) {
							sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u '%s' '%s' is not an integer", i + 1, k + 1, name, name2);
						}
						if(!strcmp(name2, "program")) {
							if(!strcmp(name, "destination"))
								range_max = 65535;
							else
								range_max = 127;
						}
						if(item2->u.integer < range_min || item2->u.integer > range_max) {
							sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u '%s' '%s' is out of range (expected %d-%d, got %" PRId64 ")", i + 1, k + 1, name, name2, range_min, range_max, item->u.integer);
							goto error;
						}
						if(!strcmp(name2, "bank"))
							++bank_found;
						else
							++program_found;
					}
					if(!bank_found && !program_found) {
						sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u '%s' contains no 'bank' or 'program'", i + 1, k + 1, name);
						goto error;
					}
					if(bank_found > 1) {
						sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u '%s' contains more than one 'bank'", i + 1, k + 1, name);
						goto error;
					}
					if(program_found > 1) {
						sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u '%s' contains more than one 'program'", i + 1, k + 1, name);
						goto error;
					}
				}
				if(!destination_found) {
					sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u is missing 'destination'", i + 1, k + 1);
					goto error;
				}
				if(destination_found > 1) {
					sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u contains more than one 'destination'", i + 1, k + 1);
					goto error;
				}
				if(source_found > 1) {
					sprintf(error_buf, "soundFont item #%u 'patchMappings' #%u contains more than one 'source'", i + 1, k + 1);
				}
			}
			patches_needed *= l;
		}
		presets_to_allocate += patches_needed;
	}

	rval->count = presets_to_allocate;
	rval->presets = calloc(sizeof(BASS_MIDI_FONTEX2), rval->count);

	if(!rval->presets) {
		strcpy(error_buf, "Out of memory");
		goto error;
	}

	preset_number = 0;

	for(i = arr->u.array.length, j = 0; i--; ++j) {
		const json_value *obj = arr->u.array.values[i];
		const json_value *path = json_object_item(obj, "fileName");
		const json_value *gain = json_object_item(obj, "gain");
		const json_value *channels = json_object_item(obj, "channels");
		const json_value *patchMappings = json_object_item(obj, "patchMappings");
		const void *bass_path;
		const char *path_ptr = path->u.string.ptr;
		unsigned int bass_flags = 0;
#ifdef _WIN32
		if(!(isalpha(*path_ptr) && path_ptr[1] == ':')) {
			if(strlen(path_ptr) + (base_path_end - base_path + 2) > 32767) {
				strcpy(error_buf, "Base path plus SoundFont relative path is longer than 32767 characters");
				goto error;
			}
			strcpy(path_temp, base_path);
			if(*base_path_end != '\\' && *base_path_end != '/')
				strcat(path_temp, "\\");
			strcat(path_temp, path_ptr);
			path_ptr = path_temp;
		}
		MultiByteToWideChar(CP_UTF8, 0, path_ptr, -1, path16, 32767);
		path16[32767] = '\0';
		bass_path = (void *)path16;
		bass_flags = BASS_UNICODE;
#else
		if(*path_ptr != '/') {
			if(strlen(path_ptr) + (base_path_end - base_path + 2) > 32767) {
				strcpy(error_buf, "Base path plus SoundFont relative path is longer than 32767 characters");
				goto error;
			}
			strcpy(path_temp, base_path);
			if(*base_path_end != '/')
				strcat(path_temp, "/");
			strcat(path_temp, path_ptr);
			path_ptr = path_temp;
		}
		bass_path = (void *)path_ptr;
#endif
		hfont = BASS_MIDI_FontInit(bass_path, bass_flags);
		if(!hfont) {
			int error_code = BASS_ErrorGetCode();
			if(error_code == BASS_ERROR_FILEOPEN) {
				sprintf(error_buf, "Could not open SoundFont bank '%s'", path->u.string.ptr);
				goto error;
			} else if(error_code == BASS_ERROR_FILEFORM) {
				sprintf(error_buf, "SoundFont bank '%s' is not a supported format", path->u.string.ptr);
				goto error;
			} else {
				sprintf(error_buf, "SoundFont bank '%s' failed to load with error #%u", path->u.string.ptr, error_code);
				goto error;
			}
		}
		if(gain->type != json_none) {
			double gain_value = 0.0;
			if(gain->type == json_integer) {
				gain_value = (double)gain->u.integer;
			} else if(gain->type == json_double) {
				gain_value = gain->u.dbl;
			}
			gain_value = pow(10.0, gain_value / 20.0);
			BASS_MIDI_FontSetVolume(hfont, gain_value);
		}
		fontex.font = hfont;
		fontex.spreset = -1;
		fontex.sbank = -1;
		fontex.dpreset = -1;
		fontex.dbank = 0;
		fontex.dbanklsb = 0;
		fontex.minchan = 0;
		fontex.numchan = 48;
		/* Simplest case, whole bank loading */
		if(channels->type == json_none && patchMappings->type == json_none) {
			rval->presets[preset_number++] = fontex;
		} else if(patchMappings->type == json_none) {
			int prevchannel = -1;
			int firstchannel = -1;
			for(k = 0, l = channels->u.array.length; k < l; ++k) {
				int channel = (int)channels->u.array.values[k]->u.integer;
				if(firstchannel < 0) {
					firstchannel = channel;
					prevchannel = channel;
				}
				if(channel > (prevchannel + 1)) {
					fontex.minchan = firstchannel;
					fontex.numchan = prevchannel - firstchannel + 1;
					rval->presets[preset_number++] = fontex;
					firstchannel = channel;
				}
				prevchannel = channel;
			}
			fontex.minchan = firstchannel;
			fontex.numchan = prevchannel - firstchannel + 1;
			rval->presets[preset_number++] = fontex;
		} else if(channels->type == json_none) {
			sflist_process_patchmappings(rval->presets + preset_number, &fontex, patchMappings, 0, 48);
			preset_number += patchMappings->u.array.length;
		} else {
			int prevchannel = -1;
			int firstchannel = -1;
			for(k = 0, l = channels->u.array.length; k < l; ++k) {
				int channel = (int)channels->u.array.values[k]->u.integer;
				if(firstchannel < 0) {
					firstchannel = channel;
					prevchannel = channel;
				}
				if(channel > (prevchannel + 1)) {
					sflist_process_patchmappings(rval->presets + preset_number, &fontex, patchMappings, firstchannel, prevchannel - firstchannel + 1);
					preset_number += patchMappings->u.array.length;
				}
				prevchannel = channel;
			}
			sflist_process_patchmappings(rval->presets + preset_number, &fontex, patchMappings, firstchannel, prevchannel - firstchannel + 1);
			preset_number += patchMappings->u.array.length;
		}
	}

	return rval;

error:
	if(hfont) {
		BASS_MIDI_FontFree(hfont);
	}
	if(rval) {
		sflist_free(rval);
	}
	return 0;
}

static int strpbrkn_all(const char *str, size_t size, const char *chrs) {
	const char *end = str + size;

	while(str < end && *chrs) {
		while(str < end && *str != *chrs) ++str;
		++str, ++chrs;
	}

	return str < end;
}

sflist_presets *sflist_load(const char *sflist, size_t size, const char *base_path, char *error) {
	sflist_presets *rval;

	json_value *list = 0;

	/* Handle Unicode byte order markers */
	if(size >= 2) {
		if((sflist[0] == 0xFF && sflist[1] == 0xFE) ||
		   (sflist[0] == 0xFE && sflist[1] == 0xFF)) {
			strcpy(error, "UTF-16 encoding is not supported at this time");
			return 0;
		}
		if(size >= 3 && sflist[0] == 0xEF &&
		   sflist[1] == 0xBB && sflist[2] == 0xBF) {
			sflist += 3;
			size -= 3;
		}
	}

	list = sflist_load_v2(sflist, size, error);

	if(!list) {
		if(!strpbrkn_all(sflist, size, "{[]}"))
			list = sflist_load_v1(sflist, size, error);
	}

	if(!list) {
		return 0;
	}

	rval = sflist_process(list, base_path, error);

	json_builder_free(list);

	return rval;
}

void sflist_free(sflist_presets *presetlist) {
	if(presetlist) {
		if(presetlist->presets) {
			unsigned int i, j;
			for(i = 0, j = presetlist->count; i < j; ++i) {
				HSOUNDFONT hfont = presetlist->presets[i].font;
				if(hfont) {
					BASS_MIDI_FontFree(hfont);
				}
			}
			free(presetlist->presets);
		}
		free(presetlist);
	}
}

const char *sflist_upgrade(const char *sflist, size_t size, char *error_buf) {
	char *rval = 0;

	json_value *list = 0;

	size_t length = 0;

	const json_serialize_opts opts = {
		json_serialize_mode_multiline,
		0,
		3 /* indent_size */
	};

	list = sflist_load_v2(sflist, size, error_buf);

	if(!list) {
		if(!strpbrkn_all(sflist, size, "{[]}"))
			list = sflist_load_v1(sflist, size, error_buf);
	}

	if(!list) {
		return 0;
	}

	length = json_measure_ex(list, opts);

	rval = (char *)malloc(length + 1);

	if(!rval) {
		strcpy(error_buf, "Out of memory");
		goto error;
	}

	json_serialize_ex(rval, list, opts);

	json_builder_free(list);

	rval[length] = '\0';

	return (const char *)rval;

error:
	if(list) {
		json_builder_free(list);
	}
	return 0;
}

void sflist_upgrade_free(const char *ptr) {
	free((void *)ptr);
}