#include "literal.h"
#include "memory.h"

#include "literal_array.h"
#include "literal_dictionary.h"

#include <stdio.h>
#include <string.h>

//utils
static void stdoutWrapper(const char* output) {
	fprintf(stdout, output);
}

//buffer the prints
static char* globalPrintBuffer = NULL;
static size_t globalPrintCapacity = 0;
static size_t globalPrintCount = 0;

//BUGFIX: string quotes shouldn't show when just printing strings, but should show when printing them as members of something else
static char quotes = 0; //set to 0 to not show string quotes

static void printToBuffer(const char* str) {
	while (strlen(str) + globalPrintCount > globalPrintCapacity) {
		int oldCapacity = globalPrintCapacity;

		globalPrintCapacity = GROW_CAPACITY(globalPrintCapacity);
		globalPrintBuffer = GROW_ARRAY(char, globalPrintBuffer, oldCapacity, globalPrintCapacity);
	}

	snprintf(globalPrintBuffer + globalPrintCount, strlen(str) + 1, "%s", str);
	globalPrintCount += strlen(str);
}

//BUGFIX: <array | dictionary> is handled oddly for specific reasons, so this flag is for the debug output of the type
bool printTypeMarker = true;

//hash util functions
static unsigned int hashString(const char* string, int length) {
	unsigned int hash = 2166136261u;

	for (int i = 0; i < length; i++) {
		hash *= string[i];
		hash *= 16777619;
	}

	return hash;
}

static unsigned int hash(unsigned int x) {
    x = ((x >> 16) ^ x) * 0x45d9f3b;
    x = ((x >> 16) ^ x) * 0x45d9f3b;
    x = (x >> 16) ^ x;
    return x;
}

//exposed functions
void printLiteral(Literal literal) {
	printLiteralCustom(literal, stdoutWrapper);
}

void printLiteralCustom(Literal literal, void (printFn)(const char*)) {
	switch(literal.type) {
		case LITERAL_NULL:
			printFn("null");
		break;

		case LITERAL_BOOLEAN:
			printFn(AS_BOOLEAN(literal) ? "true" : "false");
		break;

		case LITERAL_INTEGER: {
			char buffer[256];
			snprintf(buffer, 256, "%d", AS_INTEGER(literal));
			printFn(buffer);
		}
		break;

		case LITERAL_FLOAT: {
			char buffer[256];
			snprintf(buffer, 256, "%g", AS_FLOAT(literal));
			printFn(buffer);
		}
		break;

		case LITERAL_STRING: {
			char buffer[4096];
			if (!quotes) {
				snprintf(buffer, 4096, "%.*s", STRLEN(literal), AS_STRING(literal));
			}
			else {
				snprintf(buffer, 4096, "%c%.*s%c", quotes, STRLEN(literal), AS_STRING(literal), quotes);
			}
			printFn(buffer);
		}
		break;

		case LITERAL_ARRAY: {
			LiteralArray* ptr = AS_ARRAY(literal);

			//hold potential parent-call buffers
			char* cacheBuffer = globalPrintBuffer;
			globalPrintBuffer = NULL;
			int cacheCapacity = globalPrintCapacity;
			globalPrintCapacity = 0;
			int cacheCount = globalPrintCount;
			globalPrintCount = 0;

			//print the contents to the global buffer
			printToBuffer("[");
			for (int i = 0; i < ptr->count; i++) {
				quotes = '"';
				printLiteralCustom(ptr->literals[i], printToBuffer);

				if (i + 1 < ptr->count) {
					printToBuffer(",");
				}
			}
			printToBuffer("]");

			//swap the parent-call buffer back into place
			char* printBuffer = globalPrintBuffer;
			int printCapacity = globalPrintCapacity;
			int printCount = globalPrintCount;

			globalPrintBuffer = cacheBuffer;
			globalPrintCapacity = cacheCapacity;
			globalPrintCount = cacheCount;

			//finally, output and cleanup
			printFn(printBuffer);
			FREE_ARRAY(char, printBuffer, printCapacity);
			quotes = 0;
		}
		break;

		case LITERAL_DICTIONARY: {
			LiteralDictionary* ptr = AS_DICTIONARY(literal);

			//hold potential parent-call buffers
			char* cacheBuffer = globalPrintBuffer;
			globalPrintBuffer = NULL;
			int cacheCapacity = globalPrintCapacity;
			globalPrintCapacity = 0;
			int cacheCount = globalPrintCount;
			globalPrintCount = 0;

			//print the contents to the global buffer
			int delimCount = 0;
			printToBuffer("[");
			for (int i = 0; i < ptr->capacity; i++) {
				if (IS_NULL(ptr->entries[i].key)) {
					continue;
				}

				if (delimCount++ > 0) {
					printToBuffer(",");
				}

				quotes = '"';
				printLiteralCustom(ptr->entries[i].key, printToBuffer);
				printToBuffer(":");
				quotes = '"';
				printLiteralCustom(ptr->entries[i].value, printToBuffer);
			}

			//empty dicts MUST have a ":" printed
			if (ptr->count == 0) {
				printToBuffer(":");
			}

			printToBuffer("]");

			//swap the parent-call buffer back into place
			char* printBuffer = globalPrintBuffer;
			int printCapacity = globalPrintCapacity;
			int printCount = globalPrintCount;

			globalPrintBuffer = cacheBuffer;
			globalPrintCapacity = cacheCapacity;
			globalPrintCount = cacheCount;

			//finally, output and cleanup
			printFn(printBuffer);
			FREE_ARRAY(char, printBuffer, printCapacity);
			quotes = 0;
		}
		break;

		case LITERAL_IDENTIFIER: {
			char buffer[256];
			snprintf(buffer, 256, "%.*s", STRLEN_I(literal), AS_IDENTIFIER(literal));
			printFn(buffer);
		}
		break;

		case LITERAL_TYPE: {
			//hold potential parent-call buffers
			char* cacheBuffer = globalPrintBuffer;
			globalPrintBuffer = NULL;
			int cacheCapacity = globalPrintCapacity;
			globalPrintCapacity = 0;
			int cacheCount = globalPrintCount;
			globalPrintCount = 0;

			//print the type
			int iterations = 0;
			if (printTypeMarker) {
				printToBuffer("<");
			}

			for (int i = 1; i < 8; i ++) { //0th bit is const
				//zero mask = any type, anys can't be const
				if (AS_TYPE(literal).mask == MASK_ANY) {
					printToBuffer("any");
					break;
				}

				if (AS_TYPE(literal).mask & MASK(i)) {
					//pretty print
					if (iterations++ > 0) {
						printToBuffer(" | ");
					}

					//special case for array AND dictionary
					if (i == TYPE_ARRAY) {
						if ((AS_TYPE(literal).mask & (MASK_ARRAY|MASK_DICTIONARY)) == (MASK_ARRAY|MASK_DICTIONARY)) {
							int pCache = printTypeMarker;
							printTypeMarker = false;
							printLiteralCustom(((Literal*)(AS_TYPE(literal).subtypes))[0], printToBuffer);
							printTypeMarker = pCache;
							continue;
						}
					}

					if (i == TYPE_DICTIONARY) {
						if ((AS_TYPE(literal).mask & (MASK_ARRAY|MASK_DICTIONARY)) == (MASK_ARRAY|MASK_DICTIONARY)) {
							int pCache = printTypeMarker;
							printTypeMarker = false;
							printLiteralCustom(((Literal*)(AS_TYPE(literal).subtypes))[1], printToBuffer);
							printTypeMarker = pCache;
							continue;
						}
					}

					switch(i) {
						case TYPE_BOOLEAN:
							printToBuffer("bool");
						break;

						case TYPE_INTEGER:
							printToBuffer("int");
						break;

						case TYPE_FLOAT:
							printToBuffer("float");
						break;

						case TYPE_STRING:
							printToBuffer("string");
						break;

						case TYPE_ARRAY: {
							//print all in the array
							printToBuffer("[");
							int it = 0;
							for (int a = 0; a < AS_TYPE(literal).count; a++) {
								if (it++ > 0) {
									printToBuffer("] | [");
								}
								printLiteralCustom(((Literal*)(AS_TYPE(literal).subtypes))[a], printToBuffer);
							}
							printToBuffer("]");
						}
						break;

						case TYPE_DICTIONARY: {
							printToBuffer("[");

							int it = 0;
							for (int a = 0; a < AS_TYPE(literal).count; a += 2) {
								if (it++ > 0) {
									printToBuffer("] | [");
								}
								printLiteralCustom(((Literal*)(AS_TYPE(literal).subtypes))[a], printToBuffer);
								printToBuffer(":");
								printLiteralCustom(((Literal*)(AS_TYPE(literal).subtypes))[a + 1], printToBuffer);
							}
							printToBuffer("]");
						}
						break;

						//TODO: function
					}
				}
			}

			//const (printed last)
			if (AS_TYPE(literal).mask & MASK_CONST) {
				if (iterations++ > 0) {
					printToBuffer(" ");
				}
				printToBuffer("const");
			}

			if (printTypeMarker) {
				printToBuffer(">");
			}

			//swap the parent-call buffer back into place
			char* printBuffer = globalPrintBuffer;
			int printCapacity = globalPrintCapacity;
			int printCount = globalPrintCount;

			globalPrintBuffer = cacheBuffer;
			globalPrintCapacity = cacheCapacity;
			globalPrintCount = cacheCount;

			//finally, output and cleanup
			printFn(printBuffer);
			FREE_ARRAY(char, printBuffer, printCapacity);
			quotes = 0;
		}
		break;

		default:
			//should never bee seen
			fprintf(stderr, "[Internal] Unrecognized literal type in print: %d\n", literal.type);
	}
}

void freeLiteral(Literal literal) {
	if (IS_STRING(literal)) {
		FREE_ARRAY(char, AS_STRING(literal), STRLEN(literal));
		return;
	}

	if (IS_IDENTIFIER(literal)) {
		FREE_ARRAY(char, AS_IDENTIFIER(literal), STRLEN_I(literal));
		return;
	}

	if (IS_TYPE(literal)) {
		for (int i = 0; i < AS_TYPE(literal).count; i++) {
			freeLiteral(((Literal*)(AS_TYPE(literal).subtypes))[i]);
		}
		return;
	}
}

bool _isTruthy(Literal x) {
	return (IS_NULL(x) || (IS_BOOLEAN(x) && AS_BOOLEAN(x)) || (IS_INTEGER(x) && AS_INTEGER(x) != 0) || (IS_FLOAT(x) && AS_FLOAT(x) != 0));
}

Literal _toStringLiteral(char* str) {
	return ((Literal){LITERAL_STRING, {.string.ptr = (char*)str, .string.length = strlen((char*)str)}});
}

Literal _toIdentifierLiteral(char* str, int length) {
	return ((Literal){LITERAL_IDENTIFIER,{.identifier.ptr = (char*)str,.identifier.length = length, .identifier.hash = hashString(str, length)}});
}

Literal* _typePushSubtype(Literal* lit, unsigned char submask) {
	if (AS_TYPE(*lit).count + 1 > AS_TYPE(*lit).capacity) {
		int oldCapacity = AS_TYPE(*lit).capacity;

		AS_TYPE(*lit).capacity = GROW_CAPACITY(oldCapacity);
		AS_TYPE(*lit).subtypes = GROW_ARRAY(Literal, AS_TYPE(*lit).subtypes, oldCapacity, AS_TYPE(*lit).capacity);
	}

	//actually push
	((Literal*)(AS_TYPE(*lit).subtypes))[ AS_TYPE(*lit).count++ ] = TO_TYPE_LITERAL( submask );
	return &((Literal*)(AS_TYPE(*lit).subtypes))[ AS_TYPE(*lit).count - 1 ];
}

char* copyString(char* original, int length) {
	char* buffer = ALLOCATE(char, length + 1);
	strncpy(buffer, original, length);
	buffer[length] = '\0';
	return buffer;
}

bool literalsAreEqual(Literal lhs, Literal rhs) {
	if (lhs.type != rhs.type) {
		// ints and floats are compatible
		if ((IS_INTEGER(lhs) || IS_FLOAT(lhs)) && (IS_INTEGER(rhs) || IS_FLOAT(rhs))) {
			if (IS_INTEGER(lhs)) {
				return AS_INTEGER(lhs) + AS_FLOAT(rhs);
			}
			else {
				return AS_FLOAT(lhs) + AS_INTEGER(rhs);
			}
		}

		return false;
	}

	switch(lhs.type) {
		case LITERAL_BOOLEAN:
			return AS_BOOLEAN(lhs) == AS_BOOLEAN(rhs);

		case LITERAL_INTEGER:
			return AS_INTEGER(lhs) == AS_INTEGER(rhs);

		case LITERAL_FLOAT:
			return AS_FLOAT(lhs) == AS_FLOAT(rhs);

		case LITERAL_STRING:
			if (STRLEN(lhs) != STRLEN(rhs)) {
				return false;
			}
			return !strncmp(AS_STRING(lhs), AS_STRING(rhs), STRLEN(lhs));

		case LITERAL_ARRAY:
			if (AS_ARRAY(lhs)->count != AS_ARRAY(rhs)->count) {
				return false;
			}
			for (int i = 0; i < AS_ARRAY(lhs)->count; i++) {
				if (!literalsAreEqual( AS_ARRAY(lhs)->literals[i], AS_ARRAY(rhs)->literals[i] )) {
					return false;
				}
			}
			return true;

		case LITERAL_DICTIONARY:
			//relatively slow, especially when nested
			for (int i = 0; i < AS_DICTIONARY(lhs)->capacity; i++) {
				if (!IS_NULL(AS_DICTIONARY(lhs)->entries[i].key)) { //only compare non-null keys
					//check it exists in rhs
					if (!existsLiteralDictionary(AS_DICTIONARY(rhs), AS_DICTIONARY(lhs)->entries[i].key)) {
						return false;
					}

					//compare the values
					if (!literalsAreEqual(AS_DICTIONARY(lhs)->entries[i].value, getLiteralDictionary(AS_DICTIONARY(rhs), AS_DICTIONARY(lhs)->entries[i].key) )) {
						return false;
					}
				}
			}
			return true;

		//TODO: functions

		case LITERAL_IDENTIFIER:
			if (HASH_I(lhs) != HASH_I(rhs) && STRLEN_I(lhs) != STRLEN_I(rhs)) {
				return false;
			}
			return !strncmp(AS_IDENTIFIER(lhs), AS_IDENTIFIER(rhs), STRLEN_I(lhs));

		case LITERAL_TYPE:
			if (AS_TYPE(lhs).mask != AS_TYPE(rhs).mask) {
				return false;
			}

			if (AS_TYPE(lhs).count != AS_TYPE(rhs).count) {
				return false;
			}

			//TODO: array & dictionaries (slot 0 is an array collection, slot 1 is a dictionary collection)
			if ((AS_TYPE(lhs).mask & (MASK_ARRAY|MASK_DICTIONARY)) == (MASK_ARRAY|MASK_DICTIONARY)) {
				//check arrays
				if (!literalsAreEqual(((Literal*)(AS_TYPE(lhs).subtypes))[0], ((Literal*)(AS_TYPE(rhs).subtypes))[0])) {
					return false;
				}

				//check dictionaries
				if (!literalsAreEqual(((Literal*)(AS_TYPE(lhs).subtypes))[1], ((Literal*)(AS_TYPE(rhs).subtypes))[1])) {
					return false;
				}
			}

			//TODO: arrays (out of order)
			if (AS_TYPE(lhs).mask & MASK_ARRAY) {
				for (int i = 0; i < AS_TYPE(lhs).count; i++) {
					bool match = false;
					for (int j = 0; j < AS_TYPE(rhs).count; j++) {
						//compare
						if (literalsAreEqual( ((Literal*)(AS_TYPE(lhs).subtypes))[i], ((Literal*)(AS_TYPE(rhs).subtypes))[j] )) {
							match = true;
							break;
						}
					}

					if (!match) {
						return false;
					}
				}
			}

			//TODO: dictionaries (out of order)
			if (AS_TYPE(lhs).mask & MASK_DICTIONARY) {
				for (int i = 0; i < AS_TYPE(lhs).count; i += 2) {
					bool match = false;
					for (int j = 0; j < AS_TYPE(rhs).count; j += 2) {
						//compare
						if (literalsAreEqual( ((Literal*)(AS_TYPE(lhs).subtypes))[i], ((Literal*)(AS_TYPE(rhs).subtypes))[j] ) && literalsAreEqual( ((Literal*)(AS_TYPE(lhs).subtypes))[i + 1], ((Literal*)(AS_TYPE(rhs).subtypes))[j + 1] )) {
							match = true;
							break;
						}
					}

					if (!match) {
						return false;
					}
				}
			}

			return true;

		default:
			//should never bee seen
			fprintf(stderr, "[Internal] Unrecognized literal type in equality: %d\n", lhs.type);
			return false;
	}
}

int hashLiteral(Literal lit) {
	switch(lit.type) {
		case LITERAL_NULL:
			return 0;

		case LITERAL_BOOLEAN:
			return AS_BOOLEAN(lit) ? 1 : 0;

		case LITERAL_INTEGER:
			return hash((unsigned int)AS_INTEGER(lit));

		case LITERAL_FLOAT:
			return hash(*(unsigned int*)(&AS_FLOAT(lit)));

		case LITERAL_STRING:
			return hashString(AS_STRING(lit), STRLEN(lit));

		case LITERAL_ARRAY: {
			unsigned int res = 0;
			for (int i = 0; i < AS_DICTIONARY(lit)->count; i++) {
				res += hashLiteral(AS_ARRAY(lit)->literals[i]);
			}
			return hash(res);
		}

		case LITERAL_DICTIONARY: {
			unsigned int res = 0;
			for (int i = 0; i < AS_DICTIONARY(lit)->capacity; i++) {
				if (!IS_NULL(AS_DICTIONARY(lit)->entries[i].key)) { //only hash non-null keys
					res += hashLiteral(AS_DICTIONARY(lit)->entries[i].key);
					res += hashLiteral(AS_DICTIONARY(lit)->entries[i].value);
				}
			}
			return hash(res);
		}

		case LITERAL_IDENTIFIER:
			return HASH_I(lit); //pre-computed

		default:
			//should never bee seen
			fprintf(stderr, "[Internal] Unrecognized literal type in hash: %d\n", lit.type);
			return 0;
	}
}