#include <stdio.h>
#include <assert.h>
#include "csv.h"
#include "api.h"

#include <string.h>
#include "person.h"
#include "vaccine.h"


#define FILE_READ_BUFFER_SIZE 2048
#define VACCINE_LOT_TYPE_NAME "VACCINE_LOT"
#define VACCINE_LOT_NUM_FIELDS 7
#define MAX_CP_LEN 5
#define MAX_VACCINE_NAME_LEN 15
#define PERSON_TYPE_NAME "PERSON"
#define PERSON_NUM_FIELDS 7
#define MAX_PERSON_DOCUMENT_LEN 9
#define MAX_PERSON_NAME_LEN 15
#define MAX_PERSON_EMAIL_LEN 30
#define MAX_PERSON_ADDRESS_LEN 30
#define VACCINE_TYPE_NAME "VACCINE"
#define DATE_LEN 10
#define TIME_LEN 5

// Get the API version information
const char* api_version() {
    return "UOC PP 20212";
}

// Load data from a CSV file. If reset is true, remove previous data
tApiError api_loadData(tApiData* data, const char* filename, bool reset) {
    tApiError error;
    FILE *fin;    
    char buffer[FILE_READ_BUFFER_SIZE];
    tCSVEntry entry;
    
    // Check input data
    assert( data != NULL );
    assert(filename != NULL);
    
    // Reset current data    
    if (reset) {
        // Remove previous information
        error = api_freeData(data);
        if (error != E_SUCCESS) {
            return error;
        }
        
        // Initialize the data
        error = api_initData(data);
        if (error != E_SUCCESS) {
            return error;
        }
    }

    // Open the input file
    fin = fopen(filename, "r");
    if (fin == NULL) {
        return E_FILE_NOT_FOUND;
    }
    
    // Read file line by line
    while (fgets(buffer, FILE_READ_BUFFER_SIZE, fin)) {
        // Remove new line character     
        buffer[strcspn(buffer, "\n\r")] = '\0';
        
        csv_initEntry(&entry);
        csv_parseEntry(&entry, buffer, NULL);
        // Add this new entry to the api Data
        error = api_addDataEntry(data, entry);
        if (error != E_SUCCESS) {
            return error;
        }
        csv_freeEntry(&entry);
    }
    
    fclose(fin);
    
    return E_SUCCESS;
}

// Initialize the data structure
tApiError api_initData(tApiData* data) {            
    //////////////////////////////////
    // Ex PR1 2b
    /////////////////////////////////
    
    population_init(&(data->population));
    vaccineList_init(&(data->vaccines));
    vaccineLotData_init(&(data->vaccineLots));
    
    return E_SUCCESS;
}

// Add a new vaccines lot
tApiError api_addVaccineLot(tApiData* data, tCSVEntry entry) {
    //////////////////////////////////
    // Ex PR1 2c
    /////////////////////////////////
    
    tApiError ret = E_NOT_IMPLEMENTED;
    
    // Verify num fields and type of entry
    if (csv_numFields(entry) == VACCINE_LOT_NUM_FIELDS) {
        if (strcmp(csv_getType(&entry),VACCINE_LOT_TYPE_NAME) == 0) {
            
            tVaccine vaccineEntry;
            tVaccineLot vaccineLotEntry;
            
            vaccineLot_parse(&vaccineEntry,&vaccineLotEntry,entry);

            if (vaccineList_find(data->vaccines,vaccineEntry.name) == NULL) {   // Vaccine does not exist in vaccineList
            
                // Add vaccine in vaccine list
                vaccineList_insert(&data->vaccines,vaccineEntry);
                
                // Get vaccine item position in vaccine list to be added on vaccineLotData
                vaccineLotEntry.vaccine = vaccineList_find(data->vaccines,vaccineEntry.name);
                vaccineLotData_add(&(data->vaccineLots),vaccineLotEntry);
            
            } else {                                                            // Vaccine already exists in vaccineList
                
                // Get vaccine item position in vaccine list to be added on vaccineLotData
                vaccineLotEntry.vaccine = vaccineList_find(data->vaccines,vaccineEntry.name);
                vaccineLotData_add(&(data->vaccineLots),vaccineLotEntry);
            }

        vaccineLot_free(&vaccineLotEntry);
        vaccine_free(&vaccineEntry);
        
        ret = E_SUCCESS;
            
        } else {
            // numFields other than valid one
            ret = E_INVALID_ENTRY_TYPE;
        }
    } else {
        // csv record type other than valid one
        ret = E_INVALID_ENTRY_FORMAT;
    }

    return ret;
}

// Get the number of persons registered on the application
int api_populationCount(tApiData data) {
    //////////////////////////////////
    // Ex PR1 2d
    /////////////////////////////////
    
    return population_len(data.population);
}

// Get the number of vaccines registered on the application
int api_vaccineCount(tApiData data) {
    //////////////////////////////////
    // Ex PR1 2d
    /////////////////////////////////
    
    return vaccineList_len(data.vaccines);
}

// Get the number of vaccine lots registered on the application
int api_vaccineLotsCount(tApiData data) {
    //////////////////////////////////
    // Ex PR1 2d
    /////////////////////////////////
    
    return vaccineLotData_len(data.vaccineLots);
}


// Free all used memory
tApiError api_freeData(tApiData* data) {
    //////////////////////////////////
    // Ex PR1 2e
    /////////////////////////////////
    
    population_free(&(data->population));
    vaccineList_free(&(data->vaccines));
    vaccineLotData_free(&(data->vaccineLots));
        
    return E_SUCCESS;
}


// Add a new entry
tApiError api_addDataEntry(tApiData* data, tCSVEntry entry) { 
    //////////////////////////////////
    // Ex PR1 2f
    /////////////////////////////////
    
    tApiError ret = E_NOT_IMPLEMENTED;
    
    // Check if entry type is Vaccine Lot and its field number is correct
    if (strcmp(csv_getType(&entry),VACCINE_LOT_TYPE_NAME) == 0) {
        if (csv_numFields(entry) == VACCINE_LOT_NUM_FIELDS) {
            
            ret = api_addVaccineLot(data,entry);
            
        } else {    // Num fields does not match
            ret = E_INVALID_ENTRY_FORMAT;
        }
        
    // Check if entry type is Person and its field number is correct
    } else if (strcmp(csv_getType(&entry),PERSON_TYPE_NAME) == 0) {
        if (csv_numFields(entry) == PERSON_NUM_FIELDS) {
            
            // Process could be implemented in a "api_addPerson()" function
            // as in "api_addVaccineLot()"
            
            tPerson entryPerson;
            person_init(&entryPerson);
            person_parse(&entryPerson,entry);
            
            // Check if person already exists
            if (population_find(data->population,entryPerson.document) == -1) {
                population_add(&(data->population),entryPerson);
                ret = E_SUCCESS;
            } else {
                ret = E_DUPLICATED_PERSON;
            }

            person_free(&entryPerson);
            
        } else {    // Num fields does not match
            ret = E_INVALID_ENTRY_FORMAT;
        }

    } else {
        ret = E_INVALID_ENTRY_TYPE;
    }
    
    return ret;
}

// Get vaccine data
tApiError api_getVaccine(tApiData data, const char *name, tCSVEntry *entry) {
    //////////////////////////////////
    // Ex PR1 3a
    /////////////////////////////////
    
    tApiError ret = E_NOT_IMPLEMENTED;
    tVaccine* found;
    char buffer[FILE_READ_BUFFER_SIZE];
    
    found = vaccineList_find(data.vaccines,name);
    
    if (found) {    // If pointer is not null, vaccine exists
        
        // Fill buffer with data from the vaccine on that pointer
        sprintf(buffer, "%s;%d;%d", found->name, found->required, found->days);
        
        // Init CSV entry and set values accordingly
        csv_initEntry(entry);
        csv_parseEntry(entry,buffer,VACCINE_TYPE_NAME);
        
        ret = E_SUCCESS;
    
    } else {        // If pointer is null, vaccine does not exist
        ret = E_VACCINE_NOT_FOUND;
    }

    return ret; 
}

// Get vaccine lot data
tApiError api_getVaccineLot(tApiData data, const char* cp, const char* vaccine, tDateTime timestamp, tCSVEntry *entry) {
    //////////////////////////////////
    // Ex PR1 3b
    /////////////////////////////////
    
    tApiError ret = E_NOT_IMPLEMENTED;
    tVaccineLot found;
    int index;
    char buffer[FILE_READ_BUFFER_SIZE];
    
    index = vaccineLotData_find(data.vaccineLots,cp,vaccine,timestamp);
    
    if (index != -1) {    // If value is not -1, vaccineLot exists
    
        vaccineLot_cpy(&found,data.vaccineLots.elems[index]);
      
        // Fill buffer with data from the vaccineLot
        sprintf(buffer, "%02d/%02d/%04d;%02d:%02d;%s;%s;%d;%d;%d", 
            found.timestamp.date.day,found.timestamp.date.month,found.timestamp.date.year,
            found.timestamp.time.hour,found.timestamp.time.minutes,
            found.cp,
            found.vaccine->name,found.vaccine->required,found.vaccine->days,
            found.doses);
            
        vaccineLot_free(&found);
        
        // Init CSV entry and set values accordingly
        csv_initEntry(entry);
        csv_parseEntry(entry,buffer,VACCINE_LOT_TYPE_NAME);
        
        ret = E_SUCCESS;
    
    } else {        // If value is -1, vaccineLot does not exist
        ret = E_LOT_NOT_FOUND;
    }
    
    return ret; 
}

// Get registered vaccines
tApiError api_getVaccines(tApiData data, tCSVData *vaccines) {
    //////////////////////////////////
    // Ex PR1 3c
    /////////////////////////////////
    
    tApiError ret = E_NOT_IMPLEMENTED;
    tCSVEntry foundVaccine;
    tVaccineNode* currentVaccine;
    char buffer[FILE_READ_BUFFER_SIZE];
    char name[MAX_VACCINE_NAME_LEN];
    int required;
    int days;
    csv_init(vaccines);
    
    currentVaccine = data.vaccines.first;
    
    // Go through all nodes in vaccine list until current one is nothing
    while (currentVaccine != NULL) {
        csv_initEntry(&foundVaccine);
        
        // Reuse previous function to get a vaccine by name and have it stored in a CSVEntry
        if (api_getVaccine(data,currentVaccine->vaccine.name,&foundVaccine) == E_SUCCESS) {

            // Read vaccine info
            csv_getAsString(foundVaccine,0,name,MAX_VACCINE_NAME_LEN+1);
            required = csv_getAsInteger(foundVaccine,1);
            days = csv_getAsInteger(foundVaccine,2);
            
            // Fill new csv string with format required
            sprintf(buffer,"%s;%d;%d",name,required,days);
            csv_addStrEntry(vaccines,buffer,VACCINE_TYPE_NAME);
            
            ret = E_SUCCESS;
        }
        
        // Clean up dynamic memory used
        csv_freeEntry(&foundVaccine);
        
        // Point currentVaccine to next element to get forward in the loop
        currentVaccine = currentVaccine->next;
    }

    return ret; 
}

// Get vaccine lots
tApiError api_getVaccineLots(tApiData data, tCSVData *lots) {
    //////////////////////////////////
    // Ex PR1 3d
    /////////////////////////////////
    
    tApiError ret = E_NOT_IMPLEMENTED;
    tCSVEntry foundLot;
    tVaccineLot currentVaccineLot;
    char buffer[FILE_READ_BUFFER_SIZE];
    tDateTime timestamp;
    char date[DATE_LEN];
    char time[TIME_LEN];
    char cp [MAX_CP_LEN];
    char vaccine [MAX_VACCINE_NAME_LEN];
    int required;
    int days;
    int doses;
    
    csv_init(lots);
    
    for (int i = 0; i < data.vaccineLots.count; i++) {
        
        vaccineLot_cpy(&currentVaccineLot,data.vaccineLots.elems[i]);
        csv_initEntry(&foundLot);
        
        if (api_getVaccineLot(data, currentVaccineLot.cp, currentVaccineLot.vaccine->name, currentVaccineLot.timestamp, &foundLot) == E_SUCCESS) {
            
            // Fill buffer with data from the vaccinelot
            sprintf(buffer, "%02d/%02d/%04d;%02d:%02d;%s;%s;%d;%d;%d", 
                currentVaccineLot.timestamp.date.day,currentVaccineLot.timestamp.date.month,currentVaccineLot.timestamp.date.year,
                currentVaccineLot.timestamp.time.hour,currentVaccineLot.timestamp.time.minutes,
                currentVaccineLot.cp,
                currentVaccineLot.vaccine->name,currentVaccineLot.vaccine->required,currentVaccineLot.vaccine->days,
                currentVaccineLot.doses);
                
            csv_addStrEntry(lots,buffer,VACCINE_LOT_TYPE_NAME);
            
            vaccineLot_free(&currentVaccineLot);
            
            ret = E_SUCCESS;
            
        }
        csv_freeEntry(&foundLot);
    }
    return ret; 
}